opencv/modules/python/cv.cpp

#include <Python.h>

#include <assert.h>

#include <opencv/cxcore.h>
#include <opencv/cv.h>
#include <opencv/cvaux.h>
#include <opencv/cvwimage.h>
#include <opencv/highgui.h>

#define MODULESTR "cv"

static PyObject *opencv_error;

struct memtrack_t {
  PyObject_HEAD
  void *ptr;
  Py_ssize_t size;
};

struct iplimage_t {
  PyObject_HEAD
  IplImage *a;
  PyObject *data;
  size_t offset;
};

struct cvmat_t {
  PyObject_HEAD
  CvMat *a;
  PyObject *data;
  size_t offset;
};

struct cvmatnd_t {
  PyObject_HEAD
  CvMatND *a;
  PyObject *data;
  size_t offset;
};

struct cvhistogram_t {
  PyObject_HEAD
  CvHistogram h;
  PyObject *bins;
};

struct cvmemstorage_t {
  PyObject_HEAD
  CvMemStorage *a;
};

struct cvseq_t {
  PyObject_HEAD
  CvSeq *a;
  PyObject *container;  // Containing cvmemstorage_t
};

struct cvset_t {
  PyObject_HEAD
  CvSet *a;
  PyObject *container;  // Containing cvmemstorage_t
  int i;
};

struct cvsubdiv2d_t {
  PyObject_HEAD
  CvSubdiv2D *a;
  PyObject *container;  // Containing cvmemstorage_t
};

struct cvsubdiv2dpoint_t {
  PyObject_HEAD
  CvSubdiv2DPoint *a;
  PyObject *container;  // Containing cvmemstorage_t
};

struct cvsubdiv2dedge_t {
  PyObject_HEAD
  CvSubdiv2DEdge a;
  PyObject *container;  // Containing cvmemstorage_t
};

struct cvlineiterator_t {
  PyObject_HEAD
  CvLineIterator iter;
  int count;
  int type;
};

typedef IplImage ROIplImage;
typedef const CvMat ROCvMat;
typedef PyObject PyCallableObject;

struct cvfont_t {
  PyObject_HEAD
  CvFont a;
};

struct cvcontourtree_t {
  PyObject_HEAD
  CvContourTree *a;
};

struct cvrng_t {
  PyObject_HEAD
  CvRNG a;
};

static int is_iplimage(PyObject *o);
static int is_cvmat(PyObject *o);
static int is_cvmatnd(PyObject *o);
static int convert_to_CvArr(PyObject *o, CvArr **dst, const char *name = "no_name");
static int convert_to_IplImage(PyObject *o, IplImage **dst, const char *name = "no_name");
static int convert_to_CvMat(PyObject *o, CvMat **dst, const char *name = "no_name");
static int convert_to_CvMatND(PyObject *o, CvMatND **dst, const char *name = "no_name");
static PyObject *what_data(PyObject *o);
static PyObject *FROM_CvMat(CvMat *r);
static PyObject *FROM_ROCvMatPTR(ROCvMat *r);
static PyObject *shareDataND(PyObject *donor, CvMatND *pdonor, CvMatND *precipient);

#define FROM_double(r)  PyFloat_FromDouble(r)
#define FROM_float(r)  PyFloat_FromDouble(r)
#define FROM_int(r)  PyInt_FromLong(r)
#define FROM_int64(r)  PyLong_FromLongLong(r)
#define FROM_unsigned(r)  PyLong_FromUnsignedLong(r)
#define FROM_CvBox2D(r) Py_BuildValue("(ff)(ff)f", r.center.x, r.center.y, r.size.width, r.size.height, r.angle)
#define FROM_CvScalar(r)  Py_BuildValue("(ffff)", r.val[0], r.val[1], r.val[2], r.val[3])
#define FROM_CvPoint(r)  Py_BuildValue("(ii)", r.x, r.y)
#define FROM_CvPoint2D32f(r) Py_BuildValue("(ff)", r.x, r.y)
#define FROM_CvPoint3D64f(r) Py_BuildValue("(fff)", r.x, r.y, r.z)
#define FROM_CvSize(r) Py_BuildValue("(ii)", r.width, r.height)
#define FROM_CvRect(r) Py_BuildValue("(iiii)", r.x, r.y, r.width, r.height)
#define FROM_CvSeqPTR(r) _FROM_CvSeqPTR(r, pyobj_storage)
#define FROM_CvSubdiv2DPTR(r) _FROM_CvSubdiv2DPTR(r, pyobj_storage)
#define FROM_CvPoint2D64f(r) Py_BuildValue("(ff)", r.x, r.y)
#define FROM_CvConnectedComp(r) Py_BuildValue("(fNN)", (r).area, FROM_CvScalar((r).value), FROM_CvRect((r).rect))

#if PYTHON_USE_NUMPY
static PyObject *fromarray(PyObject *o, int allowND);
#endif

static void translate_error_to_exception(void)
{
  PyErr_SetString(opencv_error, cvErrorStr(cvGetErrStatus()));
  cvSetErrStatus(0);
}

#define ERRCHK do { if (cvGetErrStatus() != 0) { translate_error_to_exception(); return NULL; } } while (0)
#define ERRWRAP(F) \
    do { \
        try \
        { \
            F; \
        } \
        catch (const cv::Exception &e) \
        { \
           PyErr_SetString(opencv_error, e.err.c_str()); \
           return NULL; \
        } \
        ERRCHK; \
    } while(0)

/************************************************************************/

static int failmsg(const char *fmt, ...)
{
  char str[1000];

  va_list ap;
  va_start(ap, fmt);
  vsnprintf(str, sizeof(str), fmt, ap);
  va_end(ap);

  PyErr_SetString(PyExc_TypeError, str);
  return 0;
}

/************************************************************************/

/* These get/setters are polymorphic, used in both iplimage and cvmat */

static PyObject *PyObject_FromCvScalar(CvScalar s, int type)
{
  int i, spe = CV_MAT_CN(type);
  PyObject *r;
  if (spe > 1) {
    r = PyTuple_New(spe);
    for (i = 0; i < spe; i++)
      PyTuple_SET_ITEM(r, i, PyFloat_FromDouble(s.val[i]));
  } else {
    r = PyFloat_FromDouble(s.val[0]);
  }
  return r;
}

static PyObject *cvarr_GetItem(PyObject *o, PyObject *key);
static int cvarr_SetItem(PyObject *o, PyObject *key, PyObject *v);

// o is a Python string or buffer object.  Return its size.

static Py_ssize_t what_size(PyObject *o)
{
  void *buffer;
  Py_ssize_t buffer_len;

  if (PyString_Check(o)) {
    return PyString_Size(o);
  } else if (PyObject_AsWriteBuffer(o, &buffer, &buffer_len) == 0) {
    return buffer_len;
  } else {
    assert(0);  // argument must be string or buffer.
    return 0;
  }
}


/************************************************************************/

CvMat *PyCvMat_AsCvMat(PyObject *o)
{
  assert(0); // not yet implemented: reference counting for CvMat in Kalman is unclear...
  return NULL;
}

#define cvReleaseIplConvKernel(x) cvReleaseStructuringElement(x)
#include "generated3.i"

/* iplimage */

static void iplimage_dealloc(PyObject *self)
{
  iplimage_t *pc = (iplimage_t*)self;
  cvReleaseImageHeader((IplImage**)&pc->a);
  Py_DECREF(pc->data);
  PyObject_Del(self);
}

static PyObject *iplimage_repr(PyObject *self)
{
  iplimage_t *cva = (iplimage_t*)self;
  IplImage* ipl = (IplImage*)(cva->a);
  char str[1000];
  sprintf(str, "<iplimage(");
  char *d = str + strlen(str);
  sprintf(d, "nChannels=%d ", ipl->nChannels);
  d += strlen(d);
  sprintf(d, "width=%d ", ipl->width);
  d += strlen(d);
  sprintf(d, "height=%d ", ipl->height);
  d += strlen(d);
  sprintf(d, "widthStep=%d ", ipl->widthStep);
  d += strlen(d);
  sprintf(d, ")>");
  return PyString_FromString(str);
}

static PyObject *iplimage_tostring(PyObject *self, PyObject *args)
{
  iplimage_t *pc = (iplimage_t*)self;
  IplImage *i;
  if (!convert_to_IplImage(self, &i, "self"))
    return NULL;
  if (i == NULL)
    return NULL;
  int bps;
  switch (i->depth) {
  case IPL_DEPTH_8U:
  case IPL_DEPTH_8S:
    bps = 1;
    break;
  case IPL_DEPTH_16U:
  case IPL_DEPTH_16S:
    bps = 2;
    break;
  case IPL_DEPTH_32S:
  case IPL_DEPTH_32F:
    bps = 4;
    break;
  case IPL_DEPTH_64F:
    bps = 8;
    break;
  default:
    return (PyObject*)failmsg("Unrecognised depth %d", i->depth);
  }
  int bpl = i->width * i->nChannels * bps;
  if (PyString_Check(pc->data) && bpl == i->widthStep && pc->offset == 0 && ((bpl * i->height) == what_size(pc->data))) {
    Py_INCREF(pc->data);
    return pc->data;
  } else {
    int l = bpl * i->height;
    char *s = new char[l];
    int y;
    for (y = 0; y < i->height; y++) {
      memcpy(s + y * bpl, i->imageData + y * i->widthStep, bpl);
    }
    PyObject *r = PyString_FromStringAndSize(s, l);
    delete s;
    return r;
  }
}

static struct PyMethodDef iplimage_methods[] =
{
  {"tostring", iplimage_tostring, METH_VARARGS},
  {NULL,          NULL}
};

static PyObject *iplimage_getnChannels(iplimage_t *cva)
{
  return PyInt_FromLong(((IplImage*)(cva->a))->nChannels);
}
static PyObject *iplimage_getwidth(iplimage_t *cva)
{
  return PyInt_FromLong(((IplImage*)(cva->a))->width);
}
static PyObject *iplimage_getheight(iplimage_t *cva)
{
  return PyInt_FromLong(((IplImage*)(cva->a))->height);
}
static PyObject *iplimage_getdepth(iplimage_t *cva)
{
  return PyLong_FromUnsignedLong((unsigned)((IplImage*)(cva->a))->depth);
}
static PyObject *iplimage_getorigin(iplimage_t *cva)
{
  return PyInt_FromLong(((IplImage*)(cva->a))->origin);
}
static void iplimage_setorigin(iplimage_t *cva, PyObject *v)
{
  ((IplImage*)(cva->a))->origin = PyInt_AsLong(v);
}

static PyGetSetDef iplimage_getseters[] = {
  {(char*)"nChannels", (getter)iplimage_getnChannels, (setter)NULL, (char*)"nChannels", NULL},
  {(char*)"channels", (getter)iplimage_getnChannels, (setter)NULL, (char*)"nChannels", NULL},
  {(char*)"width", (getter)iplimage_getwidth, (setter)NULL, (char*)"width", NULL},
  {(char*)"height", (getter)iplimage_getheight, (setter)NULL, (char*)"height", NULL},
  {(char*)"depth", (getter)iplimage_getdepth, (setter)NULL, (char*)"depth", NULL},
  {(char*)"origin", (getter)iplimage_getorigin, (setter)iplimage_setorigin, (char*)"origin", NULL},
  {NULL}  /* Sentinel */
};

static PyMappingMethods iplimage_as_map = {
  NULL,
  &cvarr_GetItem,
  &cvarr_SetItem,
};

static PyTypeObject iplimage_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".iplimage",                          /*name*/
  sizeof(iplimage_t),                        /*basicsize*/
};

static void iplimage_specials(void)
{
  iplimage_Type.tp_dealloc = iplimage_dealloc;
  iplimage_Type.tp_as_mapping = &iplimage_as_map;
  iplimage_Type.tp_repr = iplimage_repr;
  iplimage_Type.tp_methods = iplimage_methods;
  iplimage_Type.tp_getset = iplimage_getseters;
}

static int is_iplimage(PyObject *o)
{
  return PyType_IsSubtype(o->ob_type, &iplimage_Type);
}

/************************************************************************/

/* cvmat */

static void cvmat_dealloc(PyObject *self)
{
  cvmat_t *pc = (cvmat_t*)self;
  if (pc->data) {
    Py_DECREF(pc->data);
  }
  cvFree(&pc->a);
  PyObject_Del(self);
}

static PyObject *cvmat_repr(PyObject *self)
{
  CvMat *m = ((cvmat_t*)self)->a;
  char str[1000];
  sprintf(str, "<cvmat(");
  char *d = str + strlen(str);
  sprintf(d, "type=%08x ", m->type);
  d += strlen(d);
  sprintf(d, "rows=%d ", m->rows);
  d += strlen(d);
  sprintf(d, "cols=%d ", m->cols);
  d += strlen(d);
  sprintf(d, "step=%d ", m->step);
  d += strlen(d);
  sprintf(d, ")>");
  return PyString_FromString(str);
}

static PyObject *cvmat_tostring(PyObject *self, PyObject *args)
{
  CvMat *m;
  if (!convert_to_CvMat(self, &m, "self"))
    return NULL;

  int bps;                     // bytes per sample

  switch (CV_MAT_DEPTH(m->type)) {
  case CV_8U:
  case CV_8S:
    bps = CV_MAT_CN(m->type) * 1;
    break;
  case CV_16U:
  case CV_16S:
    bps = CV_MAT_CN(m->type) * 2;
    break;
  case CV_32S:
  case CV_32F:
    bps = CV_MAT_CN(m->type) * 4;
    break;
  case CV_64F:
    bps = CV_MAT_CN(m->type) * 8;
    break;
  default:
    return (PyObject*)failmsg("Unrecognised depth %d", CV_MAT_DEPTH(m->type));
  }

  int bpl = m->cols * bps; // bytes per line
  cvmat_t *pc = (cvmat_t*)self;
  if (PyString_Check(pc->data) && bpl == m->step && pc->offset == 0 && ((bpl * m->rows) == what_size(pc->data))) {
    Py_INCREF(pc->data);
    return pc->data;
  } else {
    int l = bpl * m->rows;
    char *s = new char[l];
    int y;
    for (y = 0; y < m->rows; y++) {
      memcpy(s + y * bpl, m->data.ptr + y * m->step, bpl);
    }
    PyObject *r = PyString_FromStringAndSize(s, l);
    delete s;
    return r;
  }
}

static struct PyMethodDef cvmat_methods[] =
{
  {"tostring", cvmat_tostring, METH_VARARGS},
  {NULL,          NULL}
};

static PyObject *cvmat_gettype(cvmat_t *cva)
{
  return PyInt_FromLong(cvGetElemType(cva->a));
}

static PyObject *cvmat_getstep(cvmat_t *cva)
{
  return PyInt_FromLong(cva->a->step);
}

static PyObject *cvmat_getrows(cvmat_t *cva)
{
  return PyInt_FromLong(cva->a->rows);
}

static PyObject *cvmat_getcols(cvmat_t *cva)
{
  return PyInt_FromLong(cva->a->cols);
}

static PyObject *cvmat_getchannels(cvmat_t *cva)
{
  return PyInt_FromLong(CV_MAT_CN(cva->a->type));
}

#if PYTHON_USE_NUMPY
#include "numpy/ndarrayobject.h"

// A PyArrayInterface, with an associated python object that should be DECREF'ed on release
struct arrayTrack {
  PyArrayInterface s;
  PyObject *o;
};

static void arrayTrackDtor(void *p)
{
  struct arrayTrack *at = (struct arrayTrack *)p;
  delete at->s.shape;
  delete at->s.strides;
  if (at->s.descr)
    Py_DECREF(at->s.descr);
  Py_DECREF(at->o);
}

// Fill in fields of PyArrayInterface s using mtype.  This code is common
// to cvmat and cvmatnd

static void arrayinterface_common(PyArrayInterface *s, int mtype)
{
  s->two = 2;

  switch (CV_MAT_DEPTH(mtype)) {
  case CV_8U:
    s->typekind = 'u';
    s->itemsize = 1;
    break;
  case CV_8S:
    s->typekind = 'i';
    s->itemsize = 1;
    break;
  case CV_16U:
    s->typekind = 'u';
    s->itemsize = 2;
    break;
  case CV_16S:
    s->typekind = 'i';
    s->itemsize = 2;
    break;
  case CV_32S:
    s->typekind = 'i';
    s->itemsize = 4;
    break;
  case CV_32F:
    s->typekind = 'f';
    s->itemsize = 4;
    break;
  case CV_64F:
    s->typekind = 'f';
    s->itemsize = 8;
    break;
  default:
    assert(0);
  }

  s->flags = NPY_WRITEABLE | NPY_NOTSWAPPED;
}

static PyObject *cvmat_array_struct(cvmat_t *cva)
{
  CvMat *m;
  convert_to_CvMat((PyObject *)cva, &m, "");

  arrayTrack *at = new arrayTrack;
  PyArrayInterface *s = &at->s;

  at->o = cva->data;
  Py_INCREF(at->o);

  arrayinterface_common(s, m->type);

  if (CV_MAT_CN(m->type) == 1) {
    s->nd = 2;
    s->shape = new npy_intp[2];
    s->shape[0] = m->rows;
    s->shape[1] = m->cols;
    s->strides = new npy_intp[2];
    s->strides[0] = m->step;
    s->strides[1] = s->itemsize;
  } else {
    s->nd = 3;
    s->shape = new npy_intp[3];
    s->shape[0] = m->rows;
    s->shape[1] = m->cols;
    s->shape[2] = CV_MAT_CN(m->type);
    s->strides = new npy_intp[3];
    s->strides[0] = m->step;
    s->strides[1] = s->itemsize * CV_MAT_CN(m->type);
    s->strides[2] = s->itemsize;
  }
  s->data = (void*)(m->data.ptr);
  s->descr = PyList_New(1);
  char typestr[10];
  sprintf(typestr, "<%c%d", s->typekind, s->itemsize);
  PyList_SetItem(s->descr, 0, Py_BuildValue("(ss)", "x", typestr));

  return PyCObject_FromVoidPtr(s, arrayTrackDtor);
}

static PyObject *cvmatnd_array_struct(cvmatnd_t *cva)
{
  CvMatND *m;
  convert_to_CvMatND((PyObject *)cva, &m, "");

  arrayTrack *at = new arrayTrack;
  PyArrayInterface *s = &at->s;

  at->o = cva->data;
  Py_INCREF(at->o);

  arrayinterface_common(s, m->type);

  int i;
  if (CV_MAT_CN(m->type) == 1) {
    s->nd = m->dims;
    s->shape = new npy_intp[s->nd];
    for (i = 0; i < s->nd; i++)
      s->shape[i] = m->dim[i].size;
    s->strides = new npy_intp[s->nd];
    for (i = 0; i < (s->nd - 1); i++)
      s->strides[i] = m->dim[i].step;
    s->strides[s->nd - 1] = s->itemsize;
  } else {
    s->nd = m->dims + 1;
    s->shape = new npy_intp[s->nd];
    for (i = 0; i < (s->nd - 1); i++)
      s->shape[i] = m->dim[i].size;
    s->shape[s->nd - 1] = CV_MAT_CN(m->type);

    s->strides = new npy_intp[s->nd];
    for (i = 0; i < (s->nd - 2); i++)
      s->strides[i] = m->dim[i].step;
    s->strides[s->nd - 2] = s->itemsize * CV_MAT_CN(m->type);
    s->strides[s->nd - 1] = s->itemsize;
  }
  s->data = (void*)(m->data.ptr);
  s->descr = PyList_New(1);
  char typestr[10];
  sprintf(typestr, "<%c%d", s->typekind, s->itemsize);
  PyList_SetItem(s->descr, 0, Py_BuildValue("(ss)", "x", typestr));

  return PyCObject_FromVoidPtr(s, arrayTrackDtor);
}
#endif

static PyGetSetDef cvmat_getseters[] = {
  {(char*)"type",   (getter)cvmat_gettype, (setter)NULL, (char*)"type",   NULL},
  {(char*)"step",   (getter)cvmat_getstep, (setter)NULL, (char*)"step",   NULL},
  {(char*)"rows",   (getter)cvmat_getrows, (setter)NULL, (char*)"rows",   NULL},
  {(char*)"cols",   (getter)cvmat_getcols, (setter)NULL, (char*)"cols",   NULL},
  {(char*)"channels",(getter)cvmat_getchannels, (setter)NULL, (char*)"channels",   NULL},
  {(char*)"width",  (getter)cvmat_getcols, (setter)NULL, (char*)"width",  NULL},
  {(char*)"height", (getter)cvmat_getrows, (setter)NULL, (char*)"height", NULL},
#if PYTHON_USE_NUMPY
  {(char*)"__array_struct__", (getter)cvmat_array_struct, (setter)NULL, (char*)"__array_struct__", NULL},
#endif
  {NULL}  /* Sentinel */
};

static PyMappingMethods cvmat_as_map = {
  NULL,
  &cvarr_GetItem,
  &cvarr_SetItem,
};

static PyTypeObject cvmat_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvmat",                      /*name*/
  sizeof(cvmat_t),                        /*basicsize*/
};

static int illegal_init(PyObject *self, PyObject *args, PyObject *kwds)
{
  PyErr_SetString(opencv_error, "Cannot create cvmat directly; use CreateMat() instead");
  return -1;
}

static void cvmat_specials(void)
{
  cvmat_Type.tp_dealloc = cvmat_dealloc;
  cvmat_Type.tp_as_mapping = &cvmat_as_map;
  cvmat_Type.tp_repr = cvmat_repr;
  cvmat_Type.tp_methods = cvmat_methods;
  cvmat_Type.tp_getset = cvmat_getseters;
  cvmat_Type.tp_init = illegal_init;
}

static int is_cvmat(PyObject *o)
{
  return PyType_IsSubtype(o->ob_type, &cvmat_Type);
}

/************************************************************************/

/* cvmatnd */

static void cvmatnd_dealloc(PyObject *self)
{
  cvmatnd_t *pc = (cvmatnd_t*)self;
  Py_DECREF(pc->data);
  PyObject_Del(self);
}

static PyObject *cvmatnd_repr(PyObject *self)
{
  CvMatND *m = ((cvmatnd_t*)self)->a;
  char str[1000];
  sprintf(str, "<cvmatnd(");
  char *d = str + strlen(str);
  sprintf(d, "type=%08x ", m->type);
  d += strlen(d);
  sprintf(d, ")>");
  return PyString_FromString(str);
}

static size_t cvmatnd_size(CvMatND *m)
{
  int bps = 1;
  switch (CV_MAT_DEPTH(m->type)) {
  case CV_8U:
  case CV_8S:
    bps = CV_MAT_CN(m->type) * 1;
    break;
  case CV_16U:
  case CV_16S:
    bps = CV_MAT_CN(m->type) * 2;
    break;
  case CV_32S:
  case CV_32F:
    bps = CV_MAT_CN(m->type) * 4;
    break;
  case CV_64F:
    bps = CV_MAT_CN(m->type) * 8;
    break;
  default:
    assert(0);
  }
  size_t l = bps;
  for (int d = 0; d < m->dims; d++) {
    l *= m->dim[d].size;
  }
  return l;
}

static PyObject *cvmatnd_tostring(PyObject *self, PyObject *args)
{
  CvMatND *m;
  if (!convert_to_CvMatND(self, &m, "self"))
    return NULL;

  int bps;
  switch (CV_MAT_DEPTH(m->type)) {
  case CV_8U:
  case CV_8S:
    bps = CV_MAT_CN(m->type) * 1;
    break;
  case CV_16U:
  case CV_16S:
    bps = CV_MAT_CN(m->type) * 2;
    break;
  case CV_32S:
  case CV_32F:
    bps = CV_MAT_CN(m->type) * 4;
    break;
  case CV_64F:
    bps = CV_MAT_CN(m->type) * 8;
    break;
  default:
    return (PyObject*)failmsg("Unrecognised depth %d", CV_MAT_DEPTH(m->type));
  }

  int l = bps;
  for (int d = 0; d < m->dims; d++) {
    l *= m->dim[d].size;
  }
  int i[CV_MAX_DIM];
  int d;
  for (d = 0; d < m->dims; d++) {
    i[d] = 0;
  }
  int rowsize = m->dim[m->dims-1].size * bps;
  char *s = new char[l];
  char *ps = s;

  int finished = 0;
  while (!finished) {
    memcpy(ps, cvPtrND(m, i), rowsize);
    ps += rowsize;
    for (d = m->dims - 2; 0 <= d; d--) {
      if (++i[d] < cvGetDimSize(m, d)) {
        break;
      } else {
        i[d] = 0;
      }
    }
    if (d < 0)
      finished = 1;
  }

  return PyString_FromStringAndSize(s, ps - s);
}

static struct PyMethodDef cvmatnd_methods[] =
{
  {"tostring", cvmatnd_tostring, METH_VARARGS},
  {NULL,          NULL}
};

static PyObject *cvmatnd_getchannels(cvmatnd_t *cva)
{
  return PyInt_FromLong(CV_MAT_CN(cva->a->type));
}

static PyGetSetDef cvmatnd_getseters[] = {
#if PYTHON_USE_NUMPY
  {(char*)"__array_struct__", (getter)cvmatnd_array_struct, (setter)NULL, (char*)"__array_struct__", NULL},
#endif
  {(char*)"channels",(getter)cvmatnd_getchannels, (setter)NULL, (char*)"channels",   NULL},
  {NULL}  /* Sentinel */
};

static PyMappingMethods cvmatnd_as_map = {
  NULL,
  &cvarr_GetItem,
  &cvarr_SetItem,
};

static PyTypeObject cvmatnd_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvmatnd",                          /*name*/
  sizeof(cvmatnd_t),                        /*basicsize*/
};

static void cvmatnd_specials(void)
{
  cvmatnd_Type.tp_dealloc = cvmatnd_dealloc;
  cvmatnd_Type.tp_as_mapping = &cvmatnd_as_map;
  cvmatnd_Type.tp_repr = cvmatnd_repr;
  cvmatnd_Type.tp_methods = cvmatnd_methods;
  cvmatnd_Type.tp_getset = cvmatnd_getseters;
}

static int is_cvmatnd(PyObject *o)
{
  return PyType_IsSubtype(o->ob_type, &cvmatnd_Type);
}

/************************************************************************/

/* cvhistogram */

static void cvhistogram_dealloc(PyObject *self)
{
  cvhistogram_t *cvh = (cvhistogram_t*)self;
  Py_DECREF(cvh->bins);
  PyObject_Del(self);
}

static PyTypeObject cvhistogram_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvhistogram",                /*name*/
  sizeof(cvhistogram_t),                  /*basicsize*/
};

static PyObject *cvhistogram_getbins(cvhistogram_t *cvh)
{
  Py_INCREF(cvh->bins);
  return cvh->bins;
}

static PyGetSetDef cvhistogram_getseters[] = {
  {(char*)"bins", (getter)cvhistogram_getbins, (setter)NULL, (char*)"bins", NULL},
  {NULL}  /* Sentinel */
};

static void cvhistogram_specials(void)
{
  cvhistogram_Type.tp_dealloc = cvhistogram_dealloc;
  cvhistogram_Type.tp_getset = cvhistogram_getseters;
}

/************************************************************************/

/* cvlineiterator */

static PyObject *cvlineiterator_iter(PyObject *o)
{
  Py_INCREF(o);
  return o;
}

static PyObject *cvlineiterator_next(PyObject *o)
{
  cvlineiterator_t *pi = (cvlineiterator_t*)o;

  if (pi->count) {
      pi->count--;

      CvScalar r;
      cvRawDataToScalar( (void*)(pi->iter.ptr), pi->type, &r);
      PyObject *pr = PyObject_FromCvScalar(r, pi->type);

      CV_NEXT_LINE_POINT(pi->iter);

      return pr;
  } else {
    return NULL;
  }
}

static PyTypeObject cvlineiterator_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvlineiterator",             /*name*/
  sizeof(cvlineiterator_t),               /*basicsize*/
};

static void cvlineiterator_specials(void)
{
  cvlineiterator_Type.tp_iter = cvlineiterator_iter;
  cvlineiterator_Type.tp_iternext = cvlineiterator_next;
}

/************************************************************************/

/* memtrack */

static void memtrack_dealloc(PyObject *self)
{
  memtrack_t *pi = (memtrack_t*)self;
  // printf("===> memtrack_dealloc %p!\n", pi->ptr);
  cvFree(&pi->ptr);
  PyObject_Del(self);
}

static PyTypeObject memtrack_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".memtrack",                          /*name*/
  sizeof(memtrack_t),                        /*basicsize*/
};

Py_ssize_t memtrack_getreadbuffer(PyObject *self, Py_ssize_t segment, void **ptrptr)
{
  *ptrptr = &((memtrack_t*)self)->ptr;
  return ((memtrack_t*)self)->size;
}

Py_ssize_t memtrack_getwritebuffer(PyObject *self, Py_ssize_t segment, void **ptrptr)
{
  *ptrptr = ((memtrack_t*)self)->ptr;
  return ((memtrack_t*)self)->size;
}

Py_ssize_t memtrack_getsegcount(PyObject *self, Py_ssize_t *lenp)
{
  return (Py_ssize_t)1;
}

PyBufferProcs memtrack_as_buffer = {
  memtrack_getreadbuffer,
  memtrack_getwritebuffer,
  memtrack_getsegcount
};

static void memtrack_specials(void)
{
  memtrack_Type.tp_dealloc = memtrack_dealloc;
  memtrack_Type.tp_as_buffer = &memtrack_as_buffer;
}

/************************************************************************/

/* cvmemstorage */

static void cvmemstorage_dealloc(PyObject *self)
{
  cvmemstorage_t *ps = (cvmemstorage_t*)self;
  cvReleaseMemStorage(&(ps->a));
  PyObject_Del(self);
}

static PyTypeObject cvmemstorage_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvmemstorage",               /*name*/
  sizeof(cvmemstorage_t),                 /*basicsize*/
};

static void cvmemstorage_specials(void)
{
  cvmemstorage_Type.tp_dealloc = cvmemstorage_dealloc;
}

/************************************************************************/

/* cvfont */

static PyTypeObject cvfont_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvfont",                     /*name*/
  sizeof(cvfont_t),                       /*basicsize*/
};

static void cvfont_specials(void) { }

/************************************************************************/

/* cvrng */

static PyTypeObject cvrng_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvrng",                     /*name*/
  sizeof(cvrng_t),                       /*basicsize*/
};

static void cvrng_specials(void)
{
}

/************************************************************************/

/* cvcontourtree */

static PyTypeObject cvcontourtree_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvcontourtree",                     /*name*/
  sizeof(cvcontourtree_t),                       /*basicsize*/
};

static void cvcontourtree_specials(void) { }


/************************************************************************/

/* cvsubdiv2dedge */

static PyTypeObject cvsubdiv2dedge_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvsubdiv2dedge",                     /*name*/
  sizeof(cvsubdiv2dedge_t),                       /*basicsize*/
};

static int cvsubdiv2dedge_compare(PyObject *o1, PyObject *o2)
{
  cvsubdiv2dedge_t *e1 = (cvsubdiv2dedge_t*)o1;
  cvsubdiv2dedge_t *e2 = (cvsubdiv2dedge_t*)o2;
  if (e1->a < e2->a)
    return -1;
  else if (e1->a > e2->a)
    return 1;
  else
    return 0;
}

static PyObject *cvquadedge_repr(PyObject *self)
{
  CvSubdiv2DEdge m = ((cvsubdiv2dedge_t*)self)->a;
  char str[1000];
  sprintf(str, "<cvsubdiv2dedge(");
  char *d = str + strlen(str);
  sprintf(d, "%zx.%d", m & ~3, (int)(m & 3));
  d += strlen(d);
  sprintf(d, ")>");
  return PyString_FromString(str);
}

static void cvsubdiv2dedge_specials(void) {
  cvsubdiv2dedge_Type.tp_compare = cvsubdiv2dedge_compare;
  cvsubdiv2dedge_Type.tp_repr = cvquadedge_repr;
}

/************************************************************************/

/* cvseq */

static void cvseq_dealloc(PyObject *self)
{
  cvseq_t *ps = (cvseq_t*)self;
  Py_DECREF(ps->container);
  PyObject_Del(self);
}

static PyObject *cvseq_h_next(PyObject *self, PyObject *args);
static PyObject *cvseq_h_prev(PyObject *self, PyObject *args);
static PyObject *cvseq_v_next(PyObject *self, PyObject *args);
static PyObject *cvseq_v_prev(PyObject *self, PyObject *args);

static struct PyMethodDef cvseq_methods[] =
{
  {"h_next", cvseq_h_next, METH_VARARGS},
  {"h_prev", cvseq_h_prev, METH_VARARGS},
  {"v_next", cvseq_v_next, METH_VARARGS},
  {"v_prev", cvseq_v_prev, METH_VARARGS},
  {NULL,          NULL}
};

static Py_ssize_t cvseq_seq_length(PyObject *o)
{
  cvseq_t *ps = (cvseq_t*)o;
  if (ps->a == NULL)
    return (Py_ssize_t)0;
  else
    return (Py_ssize_t)(ps->a->total);
}

static PyObject* cvseq_seq_getitem(PyObject *o, Py_ssize_t i)
{
  cvseq_t *ps = (cvseq_t*)o;
  CvPoint *pt;
  struct pointpair{
    CvPoint a, b;
  } *pp;
  CvPoint2D32f *pt2;
  CvPoint3D32f *pt3;

  if (i < cvseq_seq_length(o)) {
    switch (CV_SEQ_ELTYPE(ps->a)) {

    case CV_SEQ_ELTYPE_POINT:
      pt = CV_GET_SEQ_ELEM(CvPoint, ps->a, i);
      return Py_BuildValue("ii", pt->x, pt->y);

    case CV_SEQ_ELTYPE_GENERIC:
      switch (ps->a->elem_size) {
      case sizeof(CvQuadEdge2D):
        {
          cvsubdiv2dedge_t *r = PyObject_NEW(cvsubdiv2dedge_t, &cvsubdiv2dedge_Type);
          r->a = (CvSubdiv2DEdge)CV_GET_SEQ_ELEM(CvQuadEdge2D, ps->a, i);
          r->container = ps->container;
          Py_INCREF(r->container);
          return (PyObject*)r;
        }
      case sizeof(CvConnectedComp):
        {
          CvConnectedComp *cc = CV_GET_SEQ_ELEM(CvConnectedComp, ps->a, i);
          return FROM_CvConnectedComp(*cc);
        }
      default:
        printf("seq elem size is %d\n", ps->a->elem_size);
        printf("KIND %d\n", CV_SEQ_KIND(ps->a));
        assert(0);
      }
      return PyInt_FromLong(*CV_GET_SEQ_ELEM(unsigned char, ps->a, i));

    case CV_SEQ_ELTYPE_PTR:
    case CV_SEQ_ELTYPE_INDEX:
      return PyInt_FromLong(*CV_GET_SEQ_ELEM(int, ps->a, i));

    case CV_32SC4:
      pp = CV_GET_SEQ_ELEM(pointpair, ps->a, i);
      return Py_BuildValue("(ii),(ii)", pp->a.x, pp->a.y, pp->b.x, pp->b.y);

    case CV_32FC2:
      pt2 = CV_GET_SEQ_ELEM(CvPoint2D32f, ps->a, i);
      return Py_BuildValue("ff", pt2->x, pt2->y);

    case CV_SEQ_ELTYPE_POINT3D:
      pt3 = CV_GET_SEQ_ELEM(CvPoint3D32f, ps->a, i);
      return Py_BuildValue("fff", pt3->x, pt3->y, pt3->z);

    default:
      printf("Unknown element type %08x\n", CV_SEQ_ELTYPE(ps->a));
      assert(0);
      return NULL;
    }
  } else
    return NULL;
}

static PyObject* cvseq_map_getitem(PyObject *o, PyObject *item)
{
  if (PyInt_Check(item)) {
    long i = PyInt_AS_LONG(item);
    if (i < 0)
      i += cvseq_seq_length(o);
    return cvseq_seq_getitem(o, i);
  } else if (PySlice_Check(item)) {
    Py_ssize_t start, stop, step, slicelength, cur, i;
    PyObject* result;

    if (PySlice_GetIndicesEx((PySliceObject*)item, cvseq_seq_length(o),
         &start, &stop, &step, &slicelength) < 0) {
      return NULL;
    }

    if (slicelength <= 0) {
      return PyList_New(0);
    } else {
      result = PyList_New(slicelength);
      if (!result) return NULL;

      for (cur = start, i = 0; i < slicelength;
           cur += step, i++) {
        PyList_SET_ITEM(result, i, cvseq_seq_getitem(o, cur));
      }

      return result;
    }
  } else {
    PyErr_SetString(PyExc_TypeError, "CvSeq indices must be integers");
    return NULL;
  }
}

static 
PySequenceMethods cvseq_sequence = {
  cvseq_seq_length,
  NULL,
  NULL,
  cvseq_seq_getitem
};

static PyMappingMethods cvseq_mapping = {
  cvseq_seq_length,
  cvseq_map_getitem,
  NULL,
};

static PyTypeObject cvseq_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvseq",                          /*name*/
  sizeof(cvseq_t),                        /*basicsize*/
};

static void cvseq_specials(void)
{
  cvseq_Type.tp_dealloc = cvseq_dealloc;
  cvseq_Type.tp_as_sequence = &cvseq_sequence;
  cvseq_Type.tp_as_mapping = &cvseq_mapping;
  cvseq_Type.tp_methods = cvseq_methods;
}

#define MK_ACCESSOR(FIELD) \
static PyObject *cvseq_##FIELD(PyObject *self, PyObject *args) \
{ \
  cvseq_t *ps = (cvseq_t*)self; \
  CvSeq *s = ps->a; \
  if (s->FIELD == NULL) { \
    Py_RETURN_NONE; \
  } else { \
    cvseq_t *r = PyObject_NEW(cvseq_t, &cvseq_Type); \
    r->a = s->FIELD; \
    r->container = ps->container; \
    Py_INCREF(r->container); \
    return (PyObject*)r; \
  } \
}

MK_ACCESSOR(h_next)
MK_ACCESSOR(h_prev)
MK_ACCESSOR(v_next)
MK_ACCESSOR(v_prev)
#undef MK_ACCESSOR

/************************************************************************/

/* cvset */

static void cvset_dealloc(PyObject *self)
{
  cvset_t *ps = (cvset_t*)self;
  Py_DECREF(ps->container);
  PyObject_Del(self);
}

static PyTypeObject cvset_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvset",                          /*name*/
  sizeof(cvset_t),                        /*basicsize*/
};

static PyObject *cvset_iter(PyObject *o)
{
  Py_INCREF(o);
  cvset_t *ps = (cvset_t*)o;
  ps->i = 0;
  return o;
}

static PyObject *cvset_next(PyObject *o)
{
  cvset_t *ps = (cvset_t*)o;

  while (ps->i < ps->a->total) {
    CvSetElem *e = cvGetSetElem(ps->a, ps->i);
    int prev_i = ps->i++;
    if (e != NULL) {
      return cvseq_seq_getitem(o, prev_i);
    }
  }
  return NULL;
}

static void cvset_specials(void)
{
  cvset_Type.tp_dealloc = cvset_dealloc;
  cvset_Type.tp_iter = cvset_iter;
  cvset_Type.tp_iternext = cvset_next;
}

/************************************************************************/

/* cvsubdiv2d */

static PyTypeObject cvsubdiv2d_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                          /*size*/
  MODULESTR".cvsubdiv2d",                     /*name*/
  sizeof(cvsubdiv2d_t),                       /*basicsize*/
};

static PyObject *cvsubdiv2d_getattro(PyObject *o, PyObject *name)
{
  cvsubdiv2d_t *p = (cvsubdiv2d_t*)o;
  if (strcmp(PyString_AsString(name), "edges") == 0) {
    cvset_t *r = PyObject_NEW(cvset_t, &cvset_Type);
    r->a = p->a->edges;
    r->container = p->container;
    Py_INCREF(r->container);
    return (PyObject*)r;
  } else {
    PyErr_SetString(PyExc_TypeError, "cvsubdiv2d has no such attribute");
    return NULL;
  }
}

static void cvsubdiv2d_specials(void)
{
  cvsubdiv2d_Type.tp_getattro = cvsubdiv2d_getattro;
}

/************************************************************************/

/* cvsubdiv2dpoint */

static PyTypeObject cvsubdiv2dpoint_Type = {
  PyObject_HEAD_INIT(&PyType_Type)
  0,                                      /*size*/
  MODULESTR".cvsubdiv2dpoint",                     /*name*/
  sizeof(cvsubdiv2dpoint_t),                       /*basicsize*/
};

static PyObject *cvsubdiv2dpoint_getattro(PyObject *o, PyObject *name)
{
  cvsubdiv2dpoint_t *p = (cvsubdiv2dpoint_t*)o;
  if (strcmp(PyString_AsString(name), "first") == 0) {
    cvsubdiv2dedge_t *r = PyObject_NEW(cvsubdiv2dedge_t, &cvsubdiv2dedge_Type);
    r->a = p->a->first;
    r->container = p->container;
    Py_INCREF(r->container);
    return (PyObject*)r;
  } else if (strcmp(PyString_AsString(name), "pt") == 0) {
    return Py_BuildValue("(ff)", p->a->pt.x, p->a->pt.y);
  } else {
    PyErr_SetString(PyExc_TypeError, "cvsubdiv2dpoint has no such attribute");
    return NULL;
  }
}

static void cvsubdiv2dpoint_specials(void)
{
  cvsubdiv2dpoint_Type.tp_getattro = cvsubdiv2dpoint_getattro;
}

/************************************************************************/
/* convert_to_X: used after PyArg_ParseTuple in the generated code  */

static int convert_to_PyObjectPTR(PyObject *o, PyObject **dst, const char *name = "no_name")
{
  *dst = o;
  return 1;
}

static int convert_to_PyCallableObjectPTR(PyObject *o, PyObject **dst, const char *name = "no_name")
{
  *dst = o;
  return 1;
}

static int convert_to_char(PyObject *o, char *dst, const char *name = "no_name")
{
  if (PyString_Check(o) && PyString_Size(o) == 1) {
    *dst = PyString_AsString(o)[0];
    return 1;
  } else {
    (*dst) = 0;
    return failmsg("Expected single character string for argument '%s'", name);
  }
}

static int convert_to_CvMemStorage(PyObject *o, CvMemStorage **dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvmemstorage_Type)) {
    (*dst) = (((cvmemstorage_t*)o)->a);
    return 1;
  } else {
    (*dst) = (CvMemStorage*)NULL;
    return failmsg("Expected CvMemStorage for argument '%s'", name);
  }
}

static int convert_to_CvSeq(PyObject *o, CvSeq **dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvseq_Type)) {
    (*dst) = (((cvseq_t*)o)->a);
    return 1;
  } else {
    (*dst) = (CvSeq*)NULL;
    return failmsg("Expected CvSeq for argument '%s'", name);
  }
}

static int convert_to_CvSize(PyObject *o, CvSize *dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "ii", &dst->width, &dst->height))
    return failmsg("CvSize argument '%s' expects two integers", name);
  else
    return 1;
}

static int convert_to_CvScalar(PyObject *o, CvScalar *s, const char *name = "no_name")
{
  if (PySequence_Check(o)) {
    PyObject *fi = PySequence_Fast(o, name);
    if (fi == NULL)
      return 0;
    if (4 < PySequence_Fast_GET_SIZE(fi))
        return failmsg("CvScalar value for argument '%s' is longer than 4", name);
    for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
      PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
      if (PyFloat_Check(item) || PyInt_Check(item)) {
        s->val[i] = PyFloat_AsDouble(item);
      } else {
        return failmsg("CvScalar value for argument '%s' is not numeric", name);
      }
    }
    Py_DECREF(fi);
  } else {
    if (PyFloat_Check(o) || PyInt_Check(o)) {
      s->val[0] = PyFloat_AsDouble(o);
    } else {
      return failmsg("CvScalar value for argument '%s' is not numeric", name);
    }
  }
  return 1;
}

static int convert_to_CvPointPTR(PyObject *o, CvPoint **p, const char *name = "no_name")
{
  if (!PySequence_Check(o))
    return failmsg("Expected sequence for point list argument '%s'", name);
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  *p = new CvPoint[PySequence_Fast_GET_SIZE(fi)];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    if (!PyTuple_Check(item))
      return failmsg("Expected tuple for element in point list argument '%s'", name);
    if (!PyArg_ParseTuple(item, "ii", &((*p)[i].x), &((*p)[i].y))) {
      return 0;
    }
  }
  Py_DECREF(fi);
  return 1;
}

static int convert_to_CvPoint2D32fPTR(PyObject *o, CvPoint2D32f **p, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  *p = new CvPoint2D32f[PySequence_Fast_GET_SIZE(fi)];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    if (!PyTuple_Check(item))
      return failmsg("Expected tuple for CvPoint2D32f argument '%s'", name);
    if (!PyArg_ParseTuple(item, "ff", &((*p)[i].x), &((*p)[i].y))) {
      return 0;
    }
  }
  Py_DECREF(fi);
  return 1;
}

#if 0 // not used
static int convert_to_CvPoint3D32fPTR(PyObject *o, CvPoint3D32f **p, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  *p = new CvPoint3D32f[PySequence_Fast_GET_SIZE(fi)];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    if (!PyTuple_Check(item))
      return failmsg("Expected tuple for CvPoint3D32f argument '%s'", name);
    if (!PyArg_ParseTuple(item, "fff", &((*p)[i].x), &((*p)[i].y), &((*p)[i].z))) {
      return 0;
    }
  }
  Py_DECREF(fi);
  return 1;
}
#endif

static int convert_to_CvStarDetectorParams(PyObject *o, CvStarDetectorParams *dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o,
                        "iiiii",
                        &dst->maxSize,
                        &dst->responseThreshold,
                        &dst->lineThresholdProjected,
                        &dst->lineThresholdBinarized,
                        &dst->suppressNonmaxSize))
    return failmsg("CvRect argument '%s' expects four integers", name);
  else
    return 1;
}

static int convert_to_CvRect(PyObject *o, CvRect *dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "iiii", &dst->x, &dst->y, &dst->width, &dst->height))
    return failmsg("CvRect argument '%s' expects four integers", name);
  else
    return 1;
}

static int convert_to_CvRectPTR(PyObject *o, CvRect **dst, const char *name = "no_name")
{
  *dst = new CvRect;
  if (!PyArg_ParseTuple(o, "iiii", &(*dst)->x, &(*dst)->y, &(*dst)->width, &(*dst)->height))
    return failmsg("CvRect argument '%s' expects four integers", name);
  else
    return 1;
}

static int convert_to_CvSlice(PyObject *o, CvSlice *dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "ii", &dst->start_index, &dst->end_index))
    return failmsg("CvSlice argument '%s' expects two integers", name);
  else
    return 1;
}

static int convert_to_CvPoint(PyObject *o, CvPoint *dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "ii", &dst->x, &dst->y))
    return failmsg("CvPoint argument '%s' expects two integers", name);
  else
    return 1;
}

static int convert_to_CvPoint2D32f(PyObject *o, CvPoint2D32f *dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "ff", &dst->x, &dst->y))
    return failmsg("CvPoint2D32f argument '%s' expects two floats", name);
  else
    return 1;
}

static int convert_to_CvPoint3D32f(PyObject *o, CvPoint3D32f *dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "fff", &dst->x, &dst->y, &dst->z))
    return failmsg("CvPoint3D32f argument '%s' expects three floats", name);
  else
    return 1;
}

static int convert_to_IplImage(PyObject *o, IplImage **dst, const char *name)
{
  iplimage_t *ipl = (iplimage_t*)o;
  void *buffer;
  Py_ssize_t buffer_len;

  if (!is_iplimage(o)) {
    return failmsg("Argument '%s' must be IplImage", name);
  } else if (PyString_Check(ipl->data)) {
    cvSetData(ipl->a, PyString_AsString(ipl->data) + ipl->offset, ipl->a->widthStep);
    assert(cvGetErrStatus() == 0);
    *dst = ipl->a;
    return 1;
  } else if (ipl->data && PyObject_AsWriteBuffer(ipl->data, &buffer, &buffer_len) == 0) {
    cvSetData(ipl->a, (void*)((char*)buffer + ipl->offset), ipl->a->widthStep);
    assert(cvGetErrStatus() == 0);
    *dst = ipl->a;
    return 1;
  } else {
    return failmsg("IplImage argument '%s' has no data", name);
  }
}

static int convert_to_CvMat(PyObject *o, CvMat **dst, const char *name)
{
  cvmat_t *m = (cvmat_t*)o;
  void *buffer;
  Py_ssize_t buffer_len;

  if (!is_cvmat(o)) {
#if !PYTHON_USE_NUMPY
    return failmsg("Argument '%s' must be CvMat", name);
#else
    PyObject *asmat = fromarray(o, 0);
    if (asmat == NULL)
      return failmsg("Argument '%s' must be CvMat", name);
    // now have the array obect as a cvmat, can use regular conversion
    return convert_to_CvMat(asmat, dst, name);
#endif
  } else {
    m->a->refcount = NULL;
    if (m->data && PyString_Check(m->data)) {
      assert(cvGetErrStatus() == 0);
      char *ptr = PyString_AsString(m->data) + m->offset;
      cvSetData(m->a, ptr, m->a->step);
      assert(cvGetErrStatus() == 0);
      *dst = m->a;
      return 1;
    } else if (m->data && PyObject_AsWriteBuffer(m->data, &buffer, &buffer_len) == 0) {
      cvSetData(m->a, (void*)((char*)buffer + m->offset), m->a->step);
      assert(cvGetErrStatus() == 0);
      *dst = m->a;
      return 1;
    } else {
      return failmsg("CvMat argument '%s' has no data", name);
    }
  }
}

static int convert_to_CvMatND(PyObject *o, CvMatND **dst, const char *name)
{
  cvmatnd_t *m = (cvmatnd_t*)o;
  void *buffer;
  Py_ssize_t buffer_len;

  if (!is_cvmatnd(o)) {
    return failmsg("Argument '%s' must be CvMatND", name);
  } else if (m->data && PyString_Check(m->data)) {
    m->a->data.ptr = ((uchar*)PyString_AsString(m->data)) + m->offset;
    *dst = m->a;
    return 1;
  } else if (m->data && PyObject_AsWriteBuffer(m->data, &buffer, &buffer_len) == 0) {
    m->a->data.ptr = ((uchar*)buffer + m->offset);
    *dst = m->a;
    return 1;
  } else {
    return failmsg("CvMatND argument '%s' has no data", name);
  }
}

static int convert_to_CvArr(PyObject *o, CvArr **dst, const char *name)
{
  if (o == Py_None) {
    *dst = (void*)NULL;
    return 1;
  } else if (is_iplimage(o)) {
    return convert_to_IplImage(o, (IplImage**)dst, name);
  } else if (is_cvmat(o)) {
    return convert_to_CvMat(o, (CvMat**)dst, name);
  } else if (is_cvmatnd(o)) {
    return convert_to_CvMatND(o, (CvMatND**)dst, name);
  } else {
#if !PYTHON_USE_NUMPY
    return failmsg("CvArr argument '%s' must be IplImage, CvMat or CvMatND", name);
#else
    PyObject *asmat = fromarray(o, 0);
    if (asmat == NULL)
      return failmsg("CvArr argument '%s' must be IplImage, CvMat, CvMatND, or support the array interface", name);
    // now have the array obect as a cvmat, can use regular conversion
    return convert_to_CvArr(asmat, dst, name);
#endif
  }
}

static int convert_to_CvHistogram(PyObject *o, CvHistogram **dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvhistogram_Type)) {
    cvhistogram_t *ht = (cvhistogram_t*)o;
    *dst = &ht->h;
    return convert_to_CvArr(ht->bins, &(ht->h.bins), "bins");
  } else {
    *dst = (CvHistogram *)NULL;
    return failmsg("Expected CvHistogram for argument '%s'", name);
  }
}

// Used by FillPoly, FillConvexPoly, PolyLine
struct pts_npts_contours {
  CvPoint** pts;
  int* npts;
  int contours;
};

static int convert_to_pts_npts_contours(PyObject *o, pts_npts_contours *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->contours = PySequence_Fast_GET_SIZE(fi);
  dst->pts = new CvPoint*[dst->contours];
  dst->npts = new int[dst->contours];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    if (!convert_to_CvPointPTR(PySequence_Fast_GET_ITEM(fi, i), &dst->pts[i], name))
      return 0;
    dst->npts[i] = PySequence_Size(PySequence_Fast_GET_ITEM(fi, i)); // safe because convert_ just succeeded
  }
  Py_DECREF(fi);
  return 1;
}

struct cvarrseq {
  union {
    CvSeq *seq;
    CvArr *mat;
  };
};

static int convert_to_cvarrseq(PyObject *o, cvarrseq *dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvseq_Type)) {
    return convert_to_CvSeq(o, &(dst->seq), name);
  } else if (PySequence_Check(o)) {
    PyObject *fi = PySequence_Fast(o, name);
    if (fi == NULL)
      return 0;
    Py_ssize_t size = -1;
    // Make a pass through the sequence, checking that each element is
    // a sequence and that they are all the same size
    for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
      PyObject *e = PySequence_Fast_GET_ITEM(fi, i);

      if (!PySequence_Check(e))
        return failmsg("Sequence '%s' must contain sequences", name);
      if (i == 0)
        size = (int)PySequence_Size(e);
      else if (size != PySequence_Size(e))
        return failmsg("All elements of sequence '%s' must be same size", name);
    }
    assert(size != -1);
    CvMat *mt = cvCreateMat((int)PySequence_Fast_GET_SIZE(fi), 1, CV_32SC(size));
    for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
      PyObject *e = PySequence_Fast_GET_ITEM(fi, i);
      PyObject *fe = PySequence_Fast(e, name);
      assert(fe != NULL);
      int *pdst = (int*)cvPtr2D(mt, i, 0);
      for (Py_ssize_t j = 0; j < size; j++) {
        *pdst++ = PyInt_AsLong(PySequence_Fast_GET_ITEM(fe, j));
      }
      Py_DECREF(fe);
    }
    Py_DECREF(fi);
    dst->mat = mt;
    return 1;
  } else {
    return convert_to_CvArr(o, &(dst->mat), name);
  }
}

struct cvarr_count {
  CvArr **cvarr;
  int count;
};

static int convert_to_cvarr_count(PyObject *o, cvarr_count *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->cvarr = new CvArr*[dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    if (!convert_to_CvArr(PySequence_Fast_GET_ITEM(fi, i), &dst->cvarr[i], name))
      return 0;
  }
  Py_DECREF(fi);
  return 1;
}

struct intpair
{
  int *pairs;
  int count;
};

static int convert_to_intpair(PyObject *o, intpair *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->pairs = new int[2 * dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    if (!PyArg_ParseTuple(item, "ii", &dst->pairs[2 * i], &dst->pairs[2 * i + 1])) {
      return 0;
    }
  }
  Py_DECREF(fi);
  return 1;
}

struct cvpoint2d32f_count {
  CvPoint2D32f* points;
  int count;
};

static int convert_to_cvpoint2d32f_count(PyObject *o, cvpoint2d32f_count *dst, const char *name = "no_name")
{
  if (PyInt_Check(o)) {
    dst->count = PyInt_AsLong(o);
    dst->points = new CvPoint2D32f[dst->count];
    return 1;
  } else {
    return failmsg("Expected integer for CvPoint2D32f count");
  }
}

struct floats {
  float *f;
  int count;
};
static int convert_to_floats(PyObject *o, floats *dst, const char *name = "no_name")
{
  if (PySequence_Check(o)) {
    PyObject *fi = PySequence_Fast(o, name);
    if (fi == NULL)
      return 0;
    dst->count = PySequence_Fast_GET_SIZE(fi);
    dst->f = new float[dst->count];
    for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
      PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
      dst->f[i] = (float)PyFloat_AsDouble(item);
    }
    Py_DECREF(fi);
  } else if (PyNumber_Check(o)) {
    dst->count = 1;
    dst->f = new float[1];
    dst->f[0] = PyFloat_AsDouble(o);
  } else {
    return failmsg("Expected list of floats, or float for argument '%s'", name);
  }
  return 1;
}

struct chars {
  char *f;
  int count;
};
/// convert_to_chars not used

struct CvPoints {
  CvPoint *p;
  int count;
};
static int convert_to_CvPoints(PyObject *o, CvPoints *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->p = new CvPoint[dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    convert_to_CvPoint(item, &dst->p[i], name);
  }
  Py_DECREF(fi);
  return 1;
}

struct CvPoint3D32fs {
  CvPoint3D32f *p;
  int count;
};
static int convert_to_CvPoint3D32fs(PyObject *o, CvPoint3D32fs *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->p = new CvPoint3D32f[dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    convert_to_CvPoint3D32f(item, &dst->p[i], name);
  }
  Py_DECREF(fi);
  return 1;
}

struct CvPoint2D32fs {
  CvPoint2D32f *p;
  int count;
};
static int convert_to_CvPoint2D32fs(PyObject *o, CvPoint2D32fs *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->p = new CvPoint2D32f[dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    convert_to_CvPoint2D32f(item, &dst->p[i], name);
  }
  Py_DECREF(fi);
  return 1;
}

struct ints {
  int *i;
  int count;
};
static int convert_to_ints(PyObject *o, ints *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->i = new int[dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    dst->i[i] = PyInt_AsLong(item);
  }
  Py_DECREF(fi);
  return 1;
}

struct ints0 {
  int *i;
  int count;
};
static int convert_to_ints0(PyObject *o, ints0 *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->i = new int[dst->count + 1];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    dst->i[i] = PyInt_AsLong(item);
  }
  dst->i[dst->count] = 0;
  Py_DECREF(fi);
  return 1;
}

struct dims
{
  int count;
  int i[CV_MAX_DIM];
  int step[CV_MAX_DIM];
  int length[CV_MAX_DIM];
};

static int convert_to_dim(PyObject *item, int i, dims *dst, CvArr *cva, const char *name = "no_name")
{
  if (PySlice_Check(item)) {
    Py_ssize_t start, stop, step, slicelength;
    PySlice_GetIndicesEx((PySliceObject*)item, cvGetDimSize(cva, i), &start, &stop, &step, &slicelength);
    dst->i[i] = start;
    dst->step[i] = step;
    dst->length[i] = slicelength;
  } else {
    int index = PyInt_AsLong(item);
    if (0 <= index)
      dst->i[i] = index;
    else
      dst->i[i] = cvGetDimSize(cva, i) + index;
    dst->step[i] = 0;
    dst->length[i] = 1;
  }
  return 1;
}

static int convert_to_dims(PyObject *o, dims *dst, CvArr *cva, const char *name = "no_name")
{
  if (!PyTuple_Check(o)) {
    dst->count = 1;
    return convert_to_dim(o, 0, dst, cva, name);
  } else {
    PyObject *fi = PySequence_Fast(o, name);
    if (fi == NULL) {
      PyErr_SetString(PyExc_TypeError, "Expected tuple for index");
      return 0;
    }
    dst->count = PySequence_Fast_GET_SIZE(fi);
    for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
      if (i >= cvGetDims(cva)) {
        return failmsg("Access specifies %d dimensions, but array only has %d", PySequence_Fast_GET_SIZE(fi), cvGetDims(cva));
      }
      PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
      if (!convert_to_dim(item, i, dst, cva, name))
        return 0;
    }
    Py_DECREF(fi);
    return 1;
  }
}

struct IplImages {
  IplImage **ims;
  int count;
};
static int convert_to_IplImages(PyObject *o, IplImages *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->ims = new IplImage*[dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    if (!convert_to_IplImage(item, &dst->ims[i]))
      return 0;
  }
  Py_DECREF(fi);
  return 1;
}

struct CvArrs {
  CvArr **ims;
  int count;
};
static int convert_to_CvArrs(PyObject *o, CvArrs *dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  dst->count = PySequence_Fast_GET_SIZE(fi);
  dst->ims = new CvArr*[dst->count];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    if (!convert_to_CvArr(item, &dst->ims[i]))
      return 0;
  }
  Py_DECREF(fi);
  return 1;
}

static int convert_to_floatPTRPTR(PyObject *o, float*** dst, const char *name = "no_name")
{
  PyObject *fi = PySequence_Fast(o, name);
  if (fi == NULL)
    return 0;
  Py_ssize_t sz = PySequence_Fast_GET_SIZE(fi);
  float **r = new float*[sz];
  for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++) {
    PyObject *item = PySequence_Fast_GET_ITEM(fi, i);
    floats ff;
    if (!convert_to_floats(item, &ff))
      return 0;
    r[i] = ff.f;
  }
  *dst = r;
  return 1;
}

static int convert_to_CvFontPTR(PyObject *o, CvFont** dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvfont_Type)) {
    (*dst) = &(((cvfont_t*)o)->a);
    return 1;
  } else {
    (*dst) = (CvFont*)NULL;
    return failmsg("Expected CvFont for argument '%s'", name);
  }
}

static int convert_to_CvContourTreePTR(PyObject *o, CvContourTree** dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvcontourtree_Type)) {
    (*dst) = ((cvcontourtree_t*)o)->a;
    return 1;
  } else {
    (*dst) = NULL;
    return failmsg("Expected CvContourTree for argument '%s'", name);
  }
}

static int convert_to_CvRNGPTR(PyObject *o, CvRNG** dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvrng_Type)) {
    (*dst) = &(((cvrng_t*)o)->a);
    return 1;
  } else {
    (*dst) = (CvRNG*)NULL;
    return failmsg("Expected CvRNG for argument '%s'", name);
  }
}

typedef void* generic;
static int convert_to_generic(PyObject *o, generic *dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &iplimage_Type))
    return convert_to_IplImage(o, (IplImage**)dst, name);
  else if (PyType_IsSubtype(o->ob_type, &cvmat_Type))
    return convert_to_CvMat(o, (CvMat**)dst, name);
  else if (PyType_IsSubtype(o->ob_type, &cvmatnd_Type))
    return convert_to_CvMatND(o, (CvMatND**)dst, name);
  else {
    return failmsg("Cannot identify type of '%s'", name);
  }
}

static int convert_to_CvTermCriteria(PyObject *o, CvTermCriteria* dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "iid", &dst->type, &dst->max_iter, &dst->epsilon))
    return 0;
  return 1;
}

static int convert_to_CvBox2D(PyObject *o, CvBox2D* dst, const char *name = "no_name")
{
  if (!PyArg_ParseTuple(o, "(ff)(ff)f", &dst->center.x, &dst->center.y, &dst->size.width, &dst->size.height, &dst->angle))
    return 0;
  return 1;
}

static int convert_to_CvSubdiv2DPTR(PyObject *o, CvSubdiv2D** dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvsubdiv2d_Type)) {
    (*dst) = (((cvsubdiv2d_t*)o)->a);
    return 1;
  } else {
    (*dst) = (CvSubdiv2D*)NULL;
    return failmsg("Expected CvSubdiv2D for argument '%s'", name);
  }
}

static int convert_to_CvNextEdgeType(PyObject *o, CvNextEdgeType *dst, const char *name = "no_name")
{
  if (!PyInt_Check(o)) {
    *dst = (CvNextEdgeType)NULL;
    return failmsg("Expected number for CvNextEdgeType argument '%s'", name);
  } else {
    *dst = (CvNextEdgeType)PyInt_AsLong(o);
    return 1;
  }
}

static int convert_to_CvSubdiv2DEdge(PyObject *o, CvSubdiv2DEdge *dst, const char *name = "no_name")
{
  if (PyType_IsSubtype(o->ob_type, &cvsubdiv2dedge_Type)) {
    (*dst) = (((cvsubdiv2dedge_t*)o)->a);
    return 1;
  } else {
    *dst = 0L;
    return failmsg("Expected CvSubdiv2DEdge for argument '%s'", name);
  }
}

/************************************************************************/

static PyObject *pythonize_CvMat(cvmat_t *m)
{
  // Need to make this CvMat look like any other, with a Python 
  // buffer object as its data.
  CvMat *mat = m->a;
  assert(mat->step != 0);
#if 0
  PyObject *data = PyString_FromStringAndSize((char*)(mat->data.ptr), mat->rows * mat->step);
#else
  memtrack_t *o = PyObject_NEW(memtrack_t, &memtrack_Type);
  size_t gap = mat->data.ptr - (uchar*)mat->refcount;
  o->ptr = mat->refcount;
  o->size = gap + mat->rows * mat->step;
  PyObject *data = PyBuffer_FromReadWriteObject((PyObject*)o, (size_t)gap, mat->rows * mat->step);
  if (data == NULL)
    return NULL;
#endif
  m->data = data;
  m->offset = 0;
  Py_DECREF(o);

  // Now m has a reference to data, which has a reference to o.

  return (PyObject*)m;
}

static PyObject *pythonize_foreign_CvMat(cvmat_t *m)
{
  // Need to make this CvMat look like any other, with a Python 
  // buffer object as its data.
  // Difference here is that the buffer is 'foreign' (from NumPy, for example)
  CvMat *mat = m->a;
  assert(mat->step != 0);
#if 0
  PyObject *data = PyString_FromStringAndSize((char*)(mat->data.ptr), mat->rows * mat->step);
#else
  memtrack_t *o = PyObject_NEW(memtrack_t, &memtrack_Type);
  o->ptr = mat->data.ptr;
  o->size = mat->rows * mat->step;
  PyObject *data = PyBuffer_FromReadWriteObject((PyObject*)o, (size_t)0, mat->rows * mat->step);
  if (data == NULL)
    return NULL;
  Py_INCREF(o);   // XXX - hack to prevent free of this foreign memory
#endif
  m->data = data;
  m->offset = 0;
  Py_DECREF(o);

  // Now m has a reference to data, which has a reference to o.

  return (PyObject*)m;
}

static PyObject *pythonize_IplImage(iplimage_t *cva)
{
  // Need to make this iplimage look like any other, with a Python 
  // string as its data.
  // So copy the image data into a Python string object, then release 
  // it.

  IplImage *ipl = (IplImage*)(cva->a);
  // PyObject *data = PyString_FromStringAndSize(ipl->imageData, ipl->imageSize);

  memtrack_t *o = PyObject_NEW(memtrack_t, &memtrack_Type);
  assert(ipl->imageDataOrigin == ipl->imageData);
  o->ptr = ipl->imageDataOrigin;
  o->size = ipl->height * ipl->widthStep;
  PyObject *data = PyBuffer_FromReadWriteObject((PyObject*)o, (size_t)0, o->size);
  if (data == NULL)
    return NULL;
  Py_DECREF(o);
  cva->data = data;
  cva->offset = 0;

  return (PyObject*)cva;
}

static PyObject *pythonize_CvMatND(cvmatnd_t *m)
{
  //
  // Need to make this CvMatND look like any other, with a Python 
  // string as its data.
  // So copy the image data into a Python string object, then release 
  // it.
  //

  CvMatND *mat = m->a;
  assert(mat->dim[0].step != 0);
#if 0
  PyObject *data = PyString_FromStringAndSize((char*)(mat->data.ptr), mat->dim[0].size * mat->dim[0].step);
#else
  memtrack_t *o = PyObject_NEW(memtrack_t, &memtrack_Type);
  o->ptr = cvPtr1D(mat, 0);
  o->size = cvmatnd_size(mat);
  PyObject *data = PyBuffer_FromReadWriteObject((PyObject*)o, (size_t)0, o->size);
  if (data == NULL)
    return NULL;
#endif
  m->data = data;
  m->offset = 0;
  // cvDecRefData(mat); // Ref count should be zero here, so this is a release

  return (PyObject*)m;
}

/************************************************************************/
/* FROM_xxx:   C -> Python converters.
 *
 * Turn various OpenCV types (and some aggregate types above)
 * into Python objects.  Used by the generated code.
 *
 * All these functions and macros return a new reference.
 */


static PyObject *_FROM_CvSeqPTR(CvSeq *s, PyObject *storage)
{
  cvseq_t *ps = PyObject_NEW(cvseq_t, &cvseq_Type);
  ps->a = s;
  ps->container = storage;
  Py_INCREF(ps->container);
  return (PyObject*)ps;
}

static PyObject *_FROM_CvSubdiv2DPTR(CvSubdiv2D *s, PyObject *storage)
{
  cvsubdiv2d_t *ps = PyObject_NEW(cvsubdiv2d_t, &cvsubdiv2d_Type);
  ps->a = s;
  ps->container = storage;
  Py_INCREF(ps->container);
  return (PyObject*)ps;
}

static PyObject *FROM_floats(floats r)
{
  PyObject *pr;

  pr = PyList_New(r.count);
  for (Py_ssize_t i = 0; i < (Py_ssize_t)r.count; i++) {
    PyList_SetItem(pr, i, PyFloat_FromDouble(r.f[i]));
  }
  return pr;
}

static PyObject *FROM_chars(chars r)
{
  PyObject *pr;

  pr = PyList_New(r.count);
  for (Py_ssize_t i = 0; i < (Py_ssize_t)r.count; i++) {
    PyList_SetItem(pr, i, PyInt_FromLong(r.f[i]));
  }
  return pr;
}

static PyObject *FROM_cvpoint2d32f_count(cvpoint2d32f_count r)
{
  PyObject *pr;

  pr = PyList_New(r.count);
  for (Py_ssize_t i = 0; i < (Py_ssize_t)r.count; i++) {
    PyList_SetItem(pr, i, FROM_CvPoint2D32f(r.points[i]));
  }
  return pr;
}

static PyObject *FROM_CvPoint2D32fs(CvPoint2D32fs r)
{
  PyObject *pr;

  pr = PyList_New(r.count);
  for (Py_ssize_t i = 0; i < (Py_ssize_t)r.count; i++) {
    PyList_SetItem(pr, i, FROM_CvPoint2D32f(r.p[i]));
  }
  return pr;
}

typedef CvSeq CvSeqOfCvConvexityDefect;
static PyObject *FROM_CvSeqOfCvConvexityDefectPTR(CvSeqOfCvConvexityDefect *r)
{
  PyObject *pr;
  pr = PyList_New(r->total);
  for (int i = 0; i < r->total; i++) {
    CvConvexityDefect *pd = CV_GET_SEQ_ELEM(CvConvexityDefect, r, i);
    PyList_SetItem(pr, i, Py_BuildValue("(ii)(ii)(ii)f",
                                        pd->start->x, pd->start->y, 
                                        pd->end->x, pd->end->y, 
                                        pd->depth_point->x, pd->depth_point->y, 
                                        pd->depth));
  }
  // This function has copied the CvSeq data into a list.  Hence the
  // CvSeq is not being returned to the caller.  Hence, no reference
  // count increase for the storage, unlike _FROM_CvSeqPTR.
  return pr;
}

typedef CvSeq CvSeqOfCvAvgComp;
static PyObject *FROM_CvSeqOfCvAvgCompPTR(CvSeqOfCvAvgComp *r)
{
  PyObject *pr;
  pr = PyList_New(r->total);
  for (int i = 0; i < r->total; i++) {
    CvAvgComp *pd = CV_GET_SEQ_ELEM(CvAvgComp, r, i);
    PyList_SetItem(pr, i, Py_BuildValue("(iiii)i",
                                        pd->rect.x, pd->rect.y, 
                                        pd->rect.width, pd->rect.height, 
                                        pd->neighbors));
  }
  // This function has copied the CvSeq data into a list.  Hence the
  // CvSeq is not being returned to the caller.  Hence, no reference
  // count increase for the storage, unlike _FROM_CvSeqPTR.
  return pr;
}

typedef CvSeq CvSeqOfCvStarKeypoint;
static PyObject *FROM_CvSeqOfCvStarKeypointPTR(CvSeqOfCvStarKeypoint *r)
{
  PyObject *pr;
  pr = PyList_New(r->total);
  for (int i = 0; i < r->total; i++) {
    CvStarKeypoint *pd = CV_GET_SEQ_ELEM(CvStarKeypoint, r, i);
    PyList_SetItem(pr, i, Py_BuildValue("(ii)if",
                                        pd->pt.x, pd->pt.y, 
                                        pd->size,
                                        pd->response));
  }
  // This function has copied the CvSeq data into a list.  Hence the
  // CvSeq is not being returned to the caller.  Hence, no reference
  // count increase for the storage, unlike _FROM_CvSeqPTR.
  return pr;
}

typedef CvSeq CvSeqOfCvSURFPoint;
static PyObject *FROM_CvSeqOfCvSURFPointPTR(CvSeqOfCvSURFPoint *r)
{
  PyObject *pr;
  pr = PyList_New(r->total);
  for (int i = 0; i < r->total; i++) {
    CvSURFPoint *pd = CV_GET_SEQ_ELEM(CvSURFPoint, r, i);
    PyList_SetItem(pr, i, Py_BuildValue("(ff)iiff",
                                        pd->pt.x, pd->pt.y, 
                                        pd->laplacian,
                                        pd->size,
                                        pd->dir,
                                        pd->hessian));
  }
  // This function has copied the CvSeq data into a list.  Hence the
  // CvSeq is not being returned to the caller.  Hence, no reference
  // count increase for the storage, unlike _FROM_CvSeqPTR.
  return pr;
}

typedef CvSeq CvSeqOfCvSURFDescriptor;
static PyObject *FROM_CvSeqOfCvSURFDescriptorPTR(CvSeqOfCvSURFDescriptor *r)
{
  PyObject *pr;
  pr = PyList_New(r->total);
  for (int i = 0; i < r->total; i++) {
    float *pd = (float*)cvGetSeqElem(r, i);
    int count = r->elem_size / sizeof(float);
    PyObject *oi = PyList_New(count);
    for (int j = 0; j < count; j++) {
      PyList_SetItem(oi, j, PyFloat_FromDouble(pd[j]));
    }
    PyList_SetItem(pr, i, oi);
  }
  // This function has copied the CvSeq data into a list.  Hence the
  // CvSeq is not being returned to the caller.  Hence, no reference
  // count increase for the storage, unlike _FROM_CvSeqPTR.
  return pr;
}

typedef CvPoint2D32f CvPoint2D32f_4[4];
static PyObject *FROM_CvPoint2D32f_4(CvPoint2D32f* r)
{
  return Py_BuildValue("(ff)(ff)(ff)(ff)",
                       r[0].x, r[0].y,
                       r[1].x, r[1].y,
                       r[2].x, r[2].y,
                       r[3].x, r[3].y);
}

typedef float CvMatr32f_i[9];

static PyObject *FROM_CvMatr32f_i(CvMatr32f_i r)
{
  return Py_BuildValue("(fff)(fff)(fff)",
    r[0], r[1], r[2],
    r[3], r[4], r[5],
    r[6], r[7], r[8]);
}

typedef float CvVect32f_i[3];
static PyObject *FROM_CvVect32f_i(CvVect32f_i r)
{
  return Py_BuildValue("fff",
    r[0], r[1], r[2]);
}

static PyObject *FROM_CvFont(CvFont r)
{
  cvfont_t *cf = PyObject_NEW(cvfont_t, &cvfont_Type);
  cf->a = r;
  return (PyObject*)cf;
}

static PyObject *FROM_CvSubdiv2DPointPTR(CvSubdiv2DPoint* r)
{
  if (r != NULL) {
    cvsubdiv2dpoint_t *cf = PyObject_NEW(cvsubdiv2dpoint_t, &cvsubdiv2dpoint_Type);
    cf->a = r;
    return (PyObject*)cf;
  } else {
    Py_INCREF(Py_None);
    return Py_None;
  }
}

static PyObject *FROM_IplImagePTR(IplImage *r)
{
  iplimage_t *cva = PyObject_NEW(iplimage_t, &iplimage_Type);
  cva->a = r;
  return pythonize_IplImage(cva);
}

static PyObject *FROM_ROIplImagePTR(ROIplImage *r)
{
  if (r != NULL) {
    iplimage_t *cva = PyObject_NEW(iplimage_t, &iplimage_Type);
    cva->a = cvCreateImageHeader(cvSize(100,100), 8, 1);
    *(cva->a) = *r;
    cva->data = PyBuffer_FromReadWriteMemory(r->imageData, r->height * r->widthStep);
    cva->offset = 0;
    return (PyObject*)cva;
  } else {
    Py_RETURN_NONE;
  }
}

static PyObject *FROM_ROCvMatPTR(ROCvMat *r)
{
  if (r != NULL) {
    cvmat_t *cva = PyObject_NEW(cvmat_t, &cvmat_Type);
    cva->a = cvCreateMatHeader(100, 100, CV_8U);
    *(cva->a) = *r;
    cva->data = PyBuffer_FromReadWriteMemory(r->data.ptr, r->rows * r->step);
    cva->offset = 0;
    return (PyObject*)cva;
  } else {
    Py_RETURN_NONE;
  }
}

static PyObject *FROM_CvMatPTR(CvMat *r)
{
  cvmat_t *cvm = PyObject_NEW(cvmat_t, &cvmat_Type);
  cvm->a = r;

  return pythonize_CvMat(cvm);
}

static PyObject *FROM_CvMat(CvMat *r)
{
  cvmat_t *m = PyObject_NEW(cvmat_t, &cvmat_Type);
  m->a = r;
  return pythonize_CvMat(m);
}

static PyObject *FROM_CvMatNDPTR(CvMatND *r)
{
  cvmatnd_t *m = PyObject_NEW(cvmatnd_t, &cvmatnd_Type);
  m->a = r;
  return pythonize_CvMatND(m);
}

static PyObject *FROM_CvRNG(CvRNG r)
{
  cvrng_t *m = PyObject_NEW(cvrng_t, &cvrng_Type);
  m->a = r;
  return (PyObject*)m;
}

static PyObject *FROM_CvContourTreePTR(CvContourTree *r)
{
  cvcontourtree_t *m = PyObject_NEW(cvcontourtree_t, &cvcontourtree_Type);
  m->a = r;
  return (PyObject*)m;
}

static PyObject *FROM_generic(generic r)
{
  CvTypeInfo* t = cvTypeOf(r);
  if (r == NULL) {
    failmsg("OpenCV returned NULL");
    return NULL;
  } if (strcmp(t->type_name, "opencv-image") == 0)
    return FROM_IplImagePTR((IplImage*)r);
  else if (strcmp(t->type_name, "opencv-matrix") == 0)
    return FROM_CvMat((CvMat*)r);
  else if (strcmp(t->type_name, "opencv-nd-matrix") == 0)
    return FROM_CvMatNDPTR((CvMatND*)r);
  else if (strcmp(t->type_name, "opencv-haar-classifier") == 0)
    return FROM_CvHaarClassifierCascadePTR((CvHaarClassifierCascade*)r);
  else {
    failmsg("Unknown OpenCV type '%s'", t->type_name);
    return NULL;
  }
}

static PyObject *FROM_CvSubdiv2DEdge(CvSubdiv2DEdge r)
{
  cvsubdiv2dedge_t *m = PyObject_NEW(cvsubdiv2dedge_t, &cvsubdiv2dedge_Type);
  m->a = r;
  m->container = Py_None; // XXX
  Py_INCREF(m->container);
  return (PyObject*)m;
}

static PyObject *FROM_CvPoints(CvPoints src)
{
  PyObject *pr;
  pr = PyList_New(src.count);
  for (int i = 0; i < src.count; i++) {
    PyList_SetItem(pr, i, FROM_CvPoint(src.p[i]));
  }
  return pr;
}

/************************************************************************/

/* A few functions are too odd to be generated, 
 * so are handwritten here */

static PyObject *pycvWaitKey(PyObject *self, PyObject *args, PyObject *kw)
{
  int delay = 0;

  const char *keywords[] = { "delay", NULL };
  if (!PyArg_ParseTupleAndKeywords(args, kw, "|i", (char**)keywords, &delay))
    return NULL;
  int r;
  Py_BEGIN_ALLOW_THREADS
  r = cvWaitKey(delay);
  Py_END_ALLOW_THREADS
  return FROM_int(r);
}

static PyObject *pycvLoadImage(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "filename", "iscolor", NULL };
  char *filename;
  int iscolor = CV_LOAD_IMAGE_COLOR;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "s|i", (char**)keywords, &filename, &iscolor))
    return NULL;

  // Inside ALLOW_THREADS, must not reference 'filename' because it might move.
  // So make a local copy 'filename_copy'.
  char filename_copy[2048];
  strncpy(filename_copy, filename, sizeof(filename_copy));

  IplImage *r;
  Py_BEGIN_ALLOW_THREADS
  r = cvLoadImage(filename_copy, iscolor);
  Py_END_ALLOW_THREADS

  if (r == NULL) {
    PyErr_SetFromErrnoWithFilename(PyExc_IOError, filename);
    return NULL;
  } else {
    return FROM_IplImagePTR(r);
  }
}

static PyObject *pycvLoadImageM(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "filename", "iscolor", NULL };
  char *filename;
  int iscolor = CV_LOAD_IMAGE_COLOR;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "s|i", (char**)keywords, &filename, &iscolor))
    return NULL;

  // Inside ALLOW_THREADS, must not reference 'filename' because it might move.
  // So make a local copy 'filename_copy'.
  char filename_copy[2048];
  strncpy(filename_copy, filename, sizeof(filename_copy));

  CvMat *r;
  Py_BEGIN_ALLOW_THREADS
  r = cvLoadImageM(filename_copy, iscolor);
  Py_END_ALLOW_THREADS

  if (r == NULL) {
    PyErr_SetFromErrnoWithFilename(PyExc_IOError, filename);
    return NULL;
  } else {
    return FROM_CvMatPTR(r);
  }
}

static PyObject *pycvCreateImageHeader(PyObject *self, PyObject *args)
{
  int w, h, depth, channels;
  if (!PyArg_ParseTuple(args, "(ii)Ii", &w, &h, &depth, &channels))
    return NULL;
  iplimage_t *cva = PyObject_NEW(iplimage_t, &iplimage_Type);
  cva->a = cvCreateImageHeader(cvSize(w, h), depth, channels);
  if (cva->a == NULL) {
    PyErr_SetString(PyExc_TypeError, "CreateImage failed");
    return NULL;
  } else {
    cva->data = Py_None;
    Py_INCREF(cva->data);
    cva->offset = 0;

    return (PyObject*)cva;
  }
}

static PyObject *pycvCreateImage(PyObject *self, PyObject *args)
{
  int w, h, depth, channels;
  if (!PyArg_ParseTuple(args, "(ii)Ii:CreateImage", &w, &h, &depth, &channels))
    return NULL;
  iplimage_t *cva = PyObject_NEW(iplimage_t, &iplimage_Type);
  ERRWRAP(cva->a = cvCreateImage(cvSize(w, h), depth, channels));
  if (cva->a == NULL) {
    PyErr_SetString(PyExc_TypeError, "CreateImage failed");
    return NULL;
  } else {
    return pythonize_IplImage(cva);
  }
}

static PyObject *pycvCreateMatHeader(PyObject *self, PyObject *args)
{
  int rows, cols, type;
  if (!PyArg_ParseTuple(args, "iii", &rows, &cols, &type))
    return NULL;
  cvmat_t *m = PyObject_NEW(cvmat_t, &cvmat_Type);
  ERRWRAP(m->a = cvCreateMatHeader(rows, cols, type));
  if (m->a == NULL) {
    PyErr_SetString(PyExc_TypeError, "CreateMat failed");
    return NULL;
  } else {
    m->data = Py_None;
    Py_INCREF(m->data);
    m->offset = 0;
    return (PyObject*)m;
  }
}

static PyObject *pycvCreateMat(PyObject *self, PyObject *args)
{
  int rows, cols, type;
  if (!PyArg_ParseTuple(args, "iii", &rows, &cols, &type))
    return NULL;
  cvmat_t *m = PyObject_NEW(cvmat_t, &cvmat_Type);
  ERRWRAP(m->a = cvCreateMat(rows, cols, type));
  if (m->a == NULL) {
    PyErr_SetString(PyExc_TypeError, "CreateMat failed");
    return NULL;
  } else {
    return pythonize_CvMat(m);
  }
}

static PyObject *pycvCreateMatNDHeader(PyObject *self, PyObject *args)
{
  ints dims;
  int type;

  if (!PyArg_ParseTuple(args, "O&i", convert_to_ints, (void*)&dims, &type))
    return NULL;
  cvmatnd_t *m = PyObject_NEW(cvmatnd_t, &cvmatnd_Type);
  ERRWRAP(m->a = cvCreateMatNDHeader(dims.count, dims.i, type));

  m->data = Py_None;
  Py_INCREF(m->data);
  return (PyObject*)m;
}


static PyObject *pycvCreateMatND(PyObject *self, PyObject *args)
{
  ints dims;
  int type;

  if (!PyArg_ParseTuple(args, "O&i", convert_to_ints, (void*)&dims, &type))
    return NULL;
  cvmatnd_t *m = PyObject_NEW(cvmatnd_t, &cvmatnd_Type);
  ERRWRAP(m->a = cvCreateMatND(dims.count, dims.i, type));
  return pythonize_CvMatND(m);
}

#if PYTHON_USE_NUMPY
static PyObject *pycvfromarray(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "arr", "allowND", NULL };
  PyObject *o;
  int allowND = 0;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "O|i", (char**)keywords, &o, &allowND))
    return NULL;
  return fromarray(o, allowND);
}

static PyObject *fromarray(PyObject *o, int allowND)
{
  PyObject *ao = PyObject_GetAttrString(o, "__array_struct__");
  if ((ao == NULL) || !PyCObject_Check(ao)) {
    PyErr_SetString(PyExc_TypeError, "object does not have array interface");
    return NULL;
  }
  PyArrayInterface *pai = (PyArrayInterface*)PyCObject_AsVoidPtr(ao);
  if (pai->two != 2) {
    PyErr_SetString(PyExc_TypeError, "object does not have array interface");
    return NULL;
  }

  int type = -1;

  switch (pai->typekind) {
  case 'i':
    if (pai->itemsize == 1)
      type = CV_8SC1;
    else if (pai->itemsize == 2)
      type = CV_16SC1;
    else if (pai->itemsize == 4)
      type = CV_32SC1;
    else if (pai->itemsize == 8) {
      PyErr_SetString(PyExc_TypeError, "OpenCV cannot handle 64-bit integer arrays");
      return NULL;
    }
    break;

  case 'u':
    if (pai->itemsize == 1)
      type = CV_8UC1;
    else if (pai->itemsize == 2)
      type = CV_16UC1;
    break;

  case 'f':
    if (pai->itemsize == 4)
      type = CV_32FC1;
    else if (pai->itemsize == 8)
      type = CV_64FC1;
    break;

  }
  assert(type != -1);

  if (!allowND) {
    cvmat_t *m = PyObject_NEW(cvmat_t, &cvmat_Type);
    if (pai->nd == 2) {
      ERRWRAP(m->a = cvCreateMatHeader(pai->shape[0], pai->shape[1], type));
      m->a->step = pai->strides[0];
    } else if (pai->nd == 3) {
      if (pai->shape[2] > CV_CN_MAX)
        return (PyObject*)failmsg("cv.fromarray too many channels, see allowND argument");
      ERRWRAP(m->a = cvCreateMatHeader(pai->shape[0], pai->shape[1], type + ((pai->shape[2] - 1) << CV_CN_SHIFT)));
      m->a->step = pai->strides[0];
    } else {
      return (PyObject*)failmsg("cv.fromarray array can be 2D or 3D only, see allowND argument");
    }
    m->a->data.ptr = (uchar*)pai->data;
    return pythonize_foreign_CvMat(m);
  } else {
    int dims[CV_MAX_DIM];
    int i;
    for (i = 0; i < pai->nd; i++)
      dims[i] = pai->shape[i];
    cvmatnd_t *m = PyObject_NEW(cvmatnd_t, &cvmatnd_Type);
    ERRWRAP(m->a = cvCreateMatND(pai->nd, dims, type));
    m->a->data.ptr = (uchar*)pai->data;
    return pythonize_CvMatND(m);
  }
}
#endif

static PyObject *pycvCreateHist(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "dims", "type", "ranges", "uniform", NULL };
  PyObject *dims;
  int type;
  float **ranges = NULL;
  int uniform = 1;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "Oi|O&i", (char**)keywords, &dims, &type, convert_to_floatPTRPTR, (void*)&ranges, &uniform)) {
    return NULL;
  }
  cvhistogram_t *h = PyObject_NEW(cvhistogram_t, &cvhistogram_Type);
  args = Py_BuildValue("Oi", dims, CV_32FC1);
  h->bins = pycvCreateMatND(self, args);
  Py_DECREF(args);
  if (h->bins == NULL) {
    return NULL;
  }
  h->h.type = CV_HIST_MAGIC_VAL;
  if (!convert_to_CvArr(h->bins, &(h->h.bins), "bins"))
    return NULL;

  ERRWRAP(cvSetHistBinRanges(&(h->h), ranges, uniform));

  return (PyObject*)h;
}

static PyObject *pycvInitLineIterator(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "image", "pt1", "pt2", "connectivity", "left_to_right", NULL };
  CvArr *image;
  CvPoint pt1;
  CvPoint pt2;
  int connectivity = 8;
  int left_to_right = 0;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "O&O&O&|ii", (char**)keywords,
                        convert_to_CvArr, &image,
                        convert_to_CvPoint, &pt1,
                        convert_to_CvPoint, &pt2,
                        &connectivity,
                        &left_to_right))
    return NULL;

  cvlineiterator_t *pi = PyObject_NEW(cvlineiterator_t, &cvlineiterator_Type);
  pi->count = cvInitLineIterator(image, pt1, pt2, &pi->iter, connectivity, left_to_right);
  ERRWRAP(pi->type = cvGetElemType(image));
  return (PyObject*)pi;
}

static PyObject *pycvCreateMemStorage(PyObject *self, PyObject *args)
{
  int block_size = 0;
  if (!PyArg_ParseTuple(args, "|i", &block_size))
    return NULL;
  cvmemstorage_t *pm = PyObject_NEW(cvmemstorage_t, &cvmemstorage_Type);
  pm->a = cvCreateMemStorage(block_size);
  return (PyObject*)pm;
}

// single index: return row
// 2 indices: row, column
// both row and column can be slices.  column slice must have a step of 1.
//
// returns a scalar when all dimensions are specified and all are integers.  Otherwise returns a CvMat.
//
static PyObject *cvarr_GetItem(PyObject *o, PyObject *key)
{
  dims dd;

  CvArr *cva;
  if (!convert_to_CvArr(o, &cva, "src"))
    return NULL;

  if (!convert_to_dims(key, &dd, cva, "key")) {
    return NULL;
  }

  // Figure out if all supplied indices have a stride of zero - means they are not slices
  // and if all indices are positive
  int all0 = 1;
  for (int i = 0; i < dd.count; i++) {
    all0 &= (dd.step[i] == 0) && (0 <= dd.i[i]);
  }

  // if every dimension supplied, and none are slices, return the scalar
  if ((cvGetDims(cva) == dd.count) && all0) {
    CvScalar s;
    ERRWRAP(s = cvGetND(cva, dd.i));
    return PyObject_FromCvScalar(s, cvGetElemType(cva));
  } else {
    // pad missing dimensions
    for (int i = dd.count; i < cvGetDims(cva); i++) {
      dd.i[i] = 0;
      dd.step[i] = 1;
      dd.length[i] = cvGetDimSize(cva, i);
    }
    dd.count = cvGetDims(cva);

    // negative steps are illegal for OpenCV
    for (int i = 0; i < dd.count; i++) {
      if (dd.step[i] < 0)
        return (PyObject*)failmsg("Negative step is illegal");
    }

    // zero length illegal for OpenCV
    for (int i = 0; i < dd.count; i++) {
      if (dd.length[i] == 0)
        return (PyObject*)failmsg("Zero sized dimension is illegal");
    }

    // column step can only be 0 or 1
    if ((dd.step[dd.count-1] != 0) && (dd.step[dd.count-1] != 1))
        return (PyObject*)failmsg("Column step is illegal");

    if (is_cvmat(o) || is_iplimage(o)) {
      cvmat_t *sub = PyObject_NEW(cvmat_t, &cvmat_Type);
      sub->a = cvCreateMatHeader(dd.length[0], dd.length[1], cvGetElemType(cva));
      uchar *old0;  // pointer to first element in old mat
      int oldstep;
      cvGetRawData(cva, &old0, &oldstep);
      uchar *new0;  // pointer to first element in new mat
      ERRWRAP(new0 = cvPtrND(cva, dd.i));

      sub->a->step = oldstep * dd.step[0];
      sub->data = what_data(o);
      Py_INCREF(sub->data);
      sub->offset = new0 - old0;
      return (PyObject*)sub;
    } else {
      cvmatnd_t *sub = PyObject_NEW(cvmatnd_t, &cvmatnd_Type);
      sub->a = cvCreateMatNDHeader(dd.count, dd.length, cvGetElemType(cva));
      uchar *old0;  // pointer to first element in old mat
      cvGetRawData(cva, &old0);
      uchar *new0;  // pointer to first element in new mat
      ERRWRAP(new0 = cvPtrND(cva, dd.i));

      for (int d = 0; d < dd.count; d++) {
        int stp = dd.step[d];
        sub->a->dim[d].step = ((CvMatND*)cva)->dim[d].step * ((stp == 0) ? 1 : stp);
        sub->a->dim[d].size = dd.length[d];
      }
      sub->data = what_data(o);
      Py_INCREF(sub->data);
      sub->offset = new0 - old0;
      return (PyObject*)sub;
    }
  }
}

static int cvarr_SetItem(PyObject *o, PyObject *key, PyObject *v)
{
  dims dd;

  CvArr *cva;
  if (!convert_to_CvArr(o, &cva, "src"))
    return -1;

  if (!convert_to_dims(key, &dd, cva, "key")) {
    return -1;
  }

  if (cvGetDims(cva) != dd.count) {
    PyErr_SetString(PyExc_TypeError, "key length does not match array dimension");
    return -1;
  }

  CvScalar s;
  if (PySequence_Check(v)) {
    PyObject *fi = PySequence_Fast(v, "v");
    if (fi == NULL)
      return -1;
    if (PySequence_Fast_GET_SIZE(fi) != CV_MAT_CN(cvGetElemType(cva))) {
      PyErr_SetString(PyExc_TypeError, "sequence size must be same as channel count");
      return -1;
    }
    for (Py_ssize_t i = 0; i < PySequence_Fast_GET_SIZE(fi); i++)
      s.val[i] = PyFloat_AsDouble(PySequence_Fast_GET_ITEM(fi, i));
    Py_DECREF(fi);
  } else {
    if (1 != CV_MAT_CN(cvGetElemType(cva))) {
      PyErr_SetString(PyExc_TypeError, "scalar supplied but channel count does not equal 1");
      return -1;
    }
    s.val[0] = PyFloat_AsDouble(v);
  }
  switch (dd.count) {
  case 1:
    cvSet1D(cva, dd.i[0], s);
    break;
  case 2:
    cvSet2D(cva, dd.i[0], dd.i[1], s);
    break;
  case 3:
    cvSet3D(cva, dd.i[0], dd.i[1], dd.i[2], s);
    break;
  default:
    cvSetND(cva, dd.i, s);
    // XXX - OpenCV bug? - seems as if an error in cvSetND does not set error status?
    break;
  }
  if (cvGetErrStatus() != 0) {
    translate_error_to_exception();
    return -1;
  }

  return 0;
}


static PyObject *pycvSetData(PyObject *self, PyObject *args)
{
  PyObject *o, *s;
  int step = CV_AUTO_STEP;

  if (!PyArg_ParseTuple(args, "OO|i", &o, &s, &step))
    return NULL;
  if (is_iplimage(o)) {
    iplimage_t *ipl = (iplimage_t*)o;
    ipl->a->widthStep = step;
    Py_DECREF(ipl->data);
    ipl->data = s;
    Py_INCREF(ipl->data);
  } else if (is_cvmat(o)) {
    cvmat_t *m = (cvmat_t*)o;
    m->a->step = step;
    Py_DECREF(m->data);
    m->data = s;
    Py_INCREF(m->data);
  } else if (is_cvmatnd(o)) {
    cvmatnd_t *m = (cvmatnd_t*)o;
    Py_DECREF(m->data);
    m->data = s;
    Py_INCREF(m->data);
  } else {
    PyErr_SetString(PyExc_TypeError, "SetData argument must be either IplImage, CvMat or CvMatND");
    return NULL;
  }

  Py_RETURN_NONE;
}

static PyObject *what_data(PyObject *o)
{
  if (is_iplimage(o)) {
    iplimage_t *ipl = (iplimage_t*)o;
    return ipl->data;
  } else if (is_cvmat(o)) {
    cvmat_t *m = (cvmat_t*)o;
    return m->data;
  } else if (is_cvmatnd(o)) {
    cvmatnd_t *m = (cvmatnd_t*)o;
    return m->data;
  } else {
    assert(0);
    return NULL;
  }
}

static PyObject *pycvCreateData(PyObject *self, PyObject *args)
{
  PyObject *o;

  if (!PyArg_ParseTuple(args, "O", &o))
    return NULL;

  CvArr *a;
  if (!convert_to_CvArr(o, &a, "arr"))
    return NULL;
  ERRWRAP(cvCreateData(a));

  Py_DECREF(what_data(o));
  if (is_iplimage(o)) {
    iplimage_t *ipl = (iplimage_t*)o;
    pythonize_IplImage(ipl);
  } else if (is_cvmat(o)) {
    cvmat_t *m = (cvmat_t*)o;
    pythonize_CvMat(m);
  } else if (is_cvmatnd(o)) {
    cvmatnd_t *m = (cvmatnd_t*)o;
    pythonize_CvMatND(m);
  } else {
    PyErr_SetString(PyExc_TypeError, "CreateData argument must be either IplImage, CvMat or CvMatND");
    return NULL;
  }

  Py_RETURN_NONE;
}

static PyObject *pycvGetDims(PyObject *self, PyObject *args)
{
  PyObject *o;

  if (!PyArg_ParseTuple(args, "O", &o))
    return NULL;
  CvArr *cva;
  if (!convert_to_CvArr(o, &cva, "src"))
    return NULL;

  int i, nd;
  ERRWRAP(nd = cvGetDims(cva));
  PyObject *r = PyTuple_New(nd);
  for (i = 0; i < nd; i++)
    PyTuple_SetItem(r, i, PyInt_FromLong(cvGetDimSize(cva, i)));
  return r;
}

static PyObject *pycvGetImage(PyObject *self, PyObject *args)
{
  PyObject *o, *r;

  if (!PyArg_ParseTuple(args, "O", &o))
    return NULL;
  if (is_iplimage(o)) {
    r = o;
    Py_INCREF(o);
  } else {
    IplImage *ipl = cvCreateImageHeader(cvSize(100,100), 8, 1); // these args do not matter, because overwritten
    CvArr *cva;
    if (!convert_to_CvArr(o, &cva, "src"))
      return NULL;
    ERRWRAP(cvGetImage(cva, ipl));

    iplimage_t *oipl = PyObject_NEW(iplimage_t, &iplimage_Type);
    oipl->a = ipl;
    oipl->data = what_data(o);
    Py_INCREF(oipl->data);
    oipl->offset = 0;

    r = (PyObject*)oipl;
  }
  return r;
}

static PyObject *pycvGetMat(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "arr", "allowND", NULL };
  PyObject *o, *r;
  int allowND = 0;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "O|i", (char**)keywords, &o, &allowND))
    return NULL;
  if (is_cvmat(o)) {
    r = o;
    Py_INCREF(o);
  } else {
    CvMat *m = cvCreateMatHeader(100,100, 1); // these args do not matter, because overwritten
    CvArr *cva;
    if (!convert_to_CvArr(o, &cva, "src"))
      return NULL;
    ERRWRAP(cvGetMat(cva, m, NULL, allowND));

    cvmat_t *om = PyObject_NEW(cvmat_t, &cvmat_Type);
    om->a = m;
    om->data = what_data(o);
    Py_INCREF(om->data);
    om->offset = 0;

    r = (PyObject*)om;
  }
  return r;
}

static PyObject *pycvReshape(PyObject *self, PyObject *args)
{
  PyObject *o;
  int new_cn;
  int new_rows = 0;

  if (!PyArg_ParseTuple(args, "Oi|i", &o, &new_cn, &new_rows))
    return NULL;

  CvMat *m = cvCreateMatHeader(100,100, 1); // these args do not matter, because overwritten
  CvArr *cva;
  if (!convert_to_CvArr(o, &cva, "src"))
    return NULL;
  ERRWRAP(cvReshape(cva, m, new_cn, new_rows));

  cvmat_t *om = PyObject_NEW(cvmat_t, &cvmat_Type);
  om->a = m;
  om->data = what_data(o);
  Py_INCREF(om->data);
  om->offset = 0;

  return (PyObject*)om;
}

static PyObject *pycvReshapeMatND(PyObject *self, PyObject *args)
{
  PyObject *o;
  int new_cn = 0;
  PyObject *new_dims = NULL;

  if (!PyArg_ParseTuple(args, "OiO", &o, &new_cn, &new_dims))
    return NULL;

  CvMatND *cva;
  if (!convert_to_CvMatND(o, &cva, "src"))
    return NULL;
  ints dims;
  if (new_dims != NULL) {
    if (!convert_to_ints(new_dims, &dims, "new_dims"))
      return NULL;
  }

  if (new_cn == 0)
    new_cn = CV_MAT_CN(cvGetElemType(cva));

  int i;
  int count = CV_MAT_CN(cvGetElemType(cva));
  for (i = 0; i < cva->dims; i++)
    count *= cva->dim[i].size;

  int newcount = new_cn;
  for (i = 0; i < dims.count; i++)
    newcount *= dims.i[i];

  if (count != newcount) {
    PyErr_SetString(PyExc_TypeError, "Total number of elements must be unchanged");
    return NULL;
  }

  CvMatND *pn = cvCreateMatNDHeader(dims.count, dims.i, CV_MAKETYPE(CV_MAT_TYPE(cva->type), new_cn));
  return shareDataND(o, cva, pn);
}

static void OnMouse(int event, int x, int y, int flags, void* param)
{
  PyGILState_STATE gstate;
  gstate = PyGILState_Ensure();

  PyObject *o = (PyObject*)param;
  PyObject *args = Py_BuildValue("iiiiO", event, x, y, flags, PyTuple_GetItem(o, 1));

  PyObject *r = PyObject_Call(PyTuple_GetItem(o, 0), args, NULL);
  if (r == NULL)
    PyErr_Print();
  else
    Py_DECREF(r);
  Py_DECREF(args);
  PyGILState_Release(gstate);
}

static PyObject *pycvSetMouseCallback(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "window_name", "on_mouse", "param", NULL };
  char* name;
  PyObject *on_mouse;
  PyObject *param = NULL;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "sO|O", (char**)keywords, &name, &on_mouse, &param))
    return NULL;
  if (!PyCallable_Check(on_mouse)) {
    PyErr_SetString(PyExc_TypeError, "on_mouse must be callable");
    return NULL;
  }
  if (param == NULL) {
    param = Py_None;
  }
  ERRWRAP(cvSetMouseCallback(name, OnMouse, Py_BuildValue("OO", on_mouse, param)));
  Py_RETURN_NONE;
}

void OnChange(int pos, void *param)
{
  PyGILState_STATE gstate;
  gstate = PyGILState_Ensure();

  PyObject *o = (PyObject*)param;
  PyObject *args = Py_BuildValue("(i)", pos);
  PyObject *r = PyObject_Call(PyTuple_GetItem(o, 0), args, NULL);
  if (r == NULL)
    PyErr_Print();
  Py_DECREF(args);
  PyGILState_Release(gstate);
}

static PyObject *pycvCreateTrackbar(PyObject *self, PyObject *args)
{
  PyObject *on_change;
  char* trackbar_name;
  char* window_name;
  int *value = new int;
  int count;

  if (!PyArg_ParseTuple(args, "ssiiO", &trackbar_name, &window_name, value, &count, &on_change))
    return NULL;
  if (!PyCallable_Check(on_change)) {
    PyErr_SetString(PyExc_TypeError, "on_change must be callable");
    return NULL;
  }
  ERRWRAP(cvCreateTrackbar2(trackbar_name, window_name, value, count, OnChange, Py_BuildValue("OO", on_change, Py_None)));
  Py_RETURN_NONE;
}

static PyObject *pycvFindContours(PyObject *self, PyObject *args, PyObject *kw)
{
  CvArr* image;
  PyObject *pyobj_image = NULL;
  CvMemStorage* storage;
  PyObject *pyobj_storage = NULL;
  CvSeq* first_contour;
  int header_size = sizeof(CvContour);
  int mode = CV_RETR_LIST;
  int method = CV_CHAIN_APPROX_SIMPLE;
  CvPoint offset = cvPoint(0,0);
  PyObject *pyobj_offset = NULL;

  const char *keywords[] = { "image", "storage", "mode", "method", "offset", NULL };
  if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|iiO", (char**)keywords, &pyobj_image, &pyobj_storage, &mode, &method, &pyobj_offset))
    return NULL;
  if (!convert_to_CvArr(pyobj_image, &image, "image")) return NULL;
  if (!convert_to_CvMemStorage(pyobj_storage, &storage, "storage")) return NULL;
  if ((pyobj_offset != NULL) && !convert_to_CvPoint(pyobj_offset, &offset, "offset")) return NULL;
  ERRWRAP(cvFindContours(image, storage, &first_contour, header_size, mode, method, offset));
  cvseq_t *ps = PyObject_NEW(cvseq_t, &cvseq_Type);
  ps->a = first_contour;
  ps->container = PyTuple_GetItem(args, 1); // storage
  Py_INCREF(ps->container);
  return (PyObject*)ps;
}

static PyObject *pycvApproxPoly(PyObject *self, PyObject *args, PyObject *kw)
{
  cvarrseq src_seq;
  PyObject *pyobj_src_seq = NULL;
  int header_size = sizeof(CvContour);
  CvMemStorage* storage;
  PyObject *pyobj_storage = NULL;
  int method;
  double parameter = 0;
  int parameter2 = 0;

  const char *keywords[] = { "src_seq", "storage", "method", "parameter", "parameter2", NULL };
  if (!PyArg_ParseTupleAndKeywords(args, kw, "OOi|di", (char**)keywords, &pyobj_src_seq, &pyobj_storage, &method, &parameter, &parameter2))
    return NULL;
  if (!convert_to_cvarrseq(pyobj_src_seq, &src_seq, "src_seq")) return NULL;
  if (!convert_to_CvMemStorage(pyobj_storage, &storage, "storage")) return NULL;
  CvSeq* r;
  ERRWRAP(r = cvApproxPoly(src_seq.mat, header_size, storage, method, parameter, parameter2));
  return FROM_CvSeqPTR(r);
}

static float distance_function_glue( const float* a, const float* b, void* user_param )
{
  PyObject *o = (PyObject*)user_param;
  PyObject *args = Py_BuildValue("(ff)(ff)O", a[0], a[1], b[0], b[1], PyTuple_GetItem(o, 1));
  PyObject *r = PyObject_Call(PyTuple_GetItem(o, 0), args, NULL);
  Py_DECREF(args);
  return (float)PyFloat_AsDouble(r);
}

static PyObject *pycvCalcEMD2(PyObject *self, PyObject *args, PyObject *kw)
{
  const char *keywords[] = { "signature1", "signature2", "distance_type", "distance_func", "cost_matrix", "flow", "lower_bound", "userdata", NULL };
  CvArr* signature1;
  PyObject *pyobj_signature1;
  CvArr* signature2;
  PyObject *pyobj_signature2;
  int distance_type;
  PyObject *distance_func = NULL;
  CvArr* cost_matrix=NULL;
  PyObject *pyobj_cost_matrix = NULL;
  CvArr* flow=NULL;
  PyObject *pyobj_flow = NULL;
  float lower_bound = 0.0;
  PyObject *userdata = NULL;

  if (!PyArg_ParseTupleAndKeywords(args, kw, "OOi|OOOfO", (char**)keywords,
                                   &pyobj_signature1,
                                   &pyobj_signature2,
                                   &distance_type,
                                   &distance_func,
                                   &pyobj_cost_matrix,
                                   &pyobj_flow,
                                   &lower_bound,
                                   &userdata))
    return NULL;
  if (!convert_to_CvArr(pyobj_signature1, &signature1, "signature1")) return NULL;
  if (!convert_to_CvArr(pyobj_signature2, &signature2, "signature2")) return NULL;
  if (pyobj_cost_matrix && !convert_to_CvArr(pyobj_cost_matrix, &cost_matrix, "cost_matrix")) return NULL;
  if (pyobj_flow && !convert_to_CvArr(pyobj_flow, &flow, "flow")) return NULL;

  if (distance_func == NULL) {
    distance_func = Py_None;
  }
  if (userdata == NULL) {
    userdata = Py_None;
  }

  PyObject *ud = Py_BuildValue("OO", distance_func, userdata);
  float r;
  ERRWRAP(r = cvCalcEMD2(signature1, signature2, distance_type, distance_function_glue, cost_matrix, flow, &lower_bound, (void*)ud));
  Py_DECREF(ud);

  return PyFloat_FromDouble(r);
}

static PyObject *pycvSubdiv2DLocate(PyObject *self, PyObject *args)
{
  PyObject *pyobj_subdiv;
  PyObject *pyobj_pt;
  CvSubdiv2D *subdiv;
  CvPoint2D32f pt;
  CvSubdiv2DEdge edge;
  CvSubdiv2DPoint* vertex;

  if (!PyArg_ParseTuple(args, "OO", &pyobj_subdiv, &pyobj_pt))
    return NULL;
  if (!convert_to_CvSubdiv2DPTR(pyobj_subdiv, &subdiv, "subdiv"))
    return NULL;
  if (!convert_to_CvPoint2D32f(pyobj_pt, &pt, "pt"))
    return NULL;

  CvSubdiv2DPointLocation loc = cvSubdiv2DLocate(subdiv, pt, &edge, &vertex);
  PyObject *r;
  switch (loc) {
  case CV_PTLOC_INSIDE:
  case CV_PTLOC_ON_EDGE:
    r = FROM_CvSubdiv2DEdge(edge);
    break;
  case CV_PTLOC_VERTEX:
    r = FROM_CvSubdiv2DPointPTR(vertex);
    break;
  case CV_PTLOC_OUTSIDE_RECT:
    r = Py_None;
    Py_INCREF(Py_None);
    break;
  default:
    return (PyObject*)failmsg("Unexpected loc from cvSubdiv2DLocate");
  }
  return Py_BuildValue("iO", (int)loc, r);
}

static PyObject *pycvCalcOpticalFlowPyrLK(PyObject *self, PyObject *args)
{
  CvArr* prev;
  PyObject *pyobj_prev = NULL;
  CvArr* curr;
  PyObject *pyobj_curr = NULL;
  CvArr* prev_pyr;
  PyObject *pyobj_prev_pyr = NULL;
  CvArr* curr_pyr;
  PyObject *pyobj_curr_pyr = NULL;
  CvPoint2D32f* prev_features;
  PyObject *pyobj_prev_features = NULL;
  PyObject *pyobj_curr_features = NULL;
  CvPoint2D32f* curr_features;
  CvSize win_size;
  int level;
  CvTermCriteria criteria;
  int flags;

  if (!PyArg_ParseTuple(args, "OOOOO(ii)i(iif)i|O",
    &pyobj_prev, &pyobj_curr, &pyobj_prev_pyr, &pyobj_curr_pyr,
    &pyobj_prev_features,
    &win_size.width, &win_size.height, &level,
    &criteria.type, &criteria.max_iter, &criteria.epsilon,
    &flags,
    &pyobj_curr_features))
    return NULL;
  if (!convert_to_CvArr(pyobj_prev, &prev, "prev")) return NULL;
  if (!convert_to_CvArr(pyobj_curr, &curr, "curr")) return NULL;
  if (!convert_to_CvArr(pyobj_prev_pyr, &prev_pyr, "prev_pyr")) return NULL;
  if (!convert_to_CvArr(pyobj_curr_pyr, &curr_pyr, "curr_pyr")) return NULL;
  if (!convert_to_CvPoint2D32fPTR(pyobj_prev_features, &prev_features, "prev_features")) return NULL;
  int count = (int)PySequence_Length(pyobj_prev_features);
  if (flags & CV_LKFLOW_INITIAL_GUESSES) {
    failmsg("flag CV_LKFLOW_INITIAL_GUESSES is determined automatically from function arguments - it is not required");
    return NULL;
  }
  if (!pyobj_curr_features) {
    curr_features = new CvPoint2D32f[count];
  } else {
    if (PySequence_Length(pyobj_curr_features) != count) {
      failmsg("curr_features must have same length as prev_features");
      return NULL;
    }
    if (!convert_to_CvPoint2D32fPTR(pyobj_curr_features, &curr_features, "curr_features")) return NULL;
    flags |= CV_LKFLOW_INITIAL_GUESSES;
  }
  float *track_error = new float[count];
  char* status = new char[count];
  ERRWRAP(cvCalcOpticalFlowPyrLK(prev, curr, prev_pyr, curr_pyr, prev_features, curr_features, count, win_size, level, status, track_error, criteria, flags));

  cvpoint2d32f_count r0;
  r0.points = curr_features;
  r0.count = count;

  chars r1;
  r1.f = status;
  r1.count = count;

  floats r2;
  r2.f = track_error;
  r2.count = count;

  return Py_BuildValue("NNN", FROM_cvpoint2d32f_count(r0), FROM_chars(r1), FROM_floats(r2));
}

// pt1,pt2 are input and output arguments here

static PyObject *pycvClipLine(PyObject *self, PyObject *args)
{
  CvSize img_size;
  PyObject *pyobj_img_size = NULL;
  CvPoint pt1;
  PyObject *pyobj_pt1 = NULL;
  CvPoint pt2;
  PyObject *pyobj_pt2 = NULL;

  if (!PyArg_ParseTuple(args, "OOO", &pyobj_img_size, &pyobj_pt1, &pyobj_pt2))
    return NULL;
  if (!convert_to_CvSize(pyobj_img_size, &img_size, "img_size")) return NULL;
  if (!convert_to_CvPoint(pyobj_pt1, &pt1, "pt1")) return NULL;
  if (!convert_to_CvPoint(pyobj_pt2, &pt2, "pt2")) return NULL;
  int r;
  ERRWRAP(r = cvClipLine(img_size, &pt1, &pt2));
  if (r == 0) {
    Py_RETURN_NONE;
  } else {
    return Py_BuildValue("NN", FROM_CvPoint(pt1), FROM_CvPoint(pt2));
  }
}

static PyObject *temp_test(PyObject *self, PyObject *args)
{
#if 0
  CvArr *im = cvLoadImage("../samples/c/lena.jpg", 0);
  printf("im=%p\n", im);
  CvMat *m = cvEncodeImage(".jpeg", im);
#endif
#if 0
  CvArr *im = cvLoadImage("lena.jpg", 0);
  float r0[] = { 0, 255 };
  float *ranges[] = { r0 };
  int hist_size[] = { 256 };
  CvHistogram *hist = cvCreateHist(1, hist_size, CV_HIST_ARRAY, ranges, 1);
  cvCalcHist(im, hist, 0, 0);
#endif

#if 0
  CvMat* mat = cvCreateMat( 3, 3, CV_32F );
  CvMat row_header, *row;
  row = cvReshape( mat, &row_header, 0, 1 );
  printf("%d,%d\n", row_header.rows, row_header.cols);
  printf("ge %08x\n", cvGetElemType(mat));
#endif

#if 0
  CvMat *m = cvCreateMat(1, 10, CV_8UC1);
  printf("CvMat stride ===> %d\n", m->step);
#endif

#if 0
  CvPoint2D32f src[3] = { { 0,0 }, { 1,0 }, { 0,1 } };
  CvPoint2D32f dst[3] = { { 0,0 }, { 17,0 }, { 0,17 } };

  CvMat* mapping = cvCreateMat(2, 3, CV_32FC1);
  cvGetAffineTransform(src, dst, mapping);
  printf("===> %f\n", cvGetReal2D(mapping, 0, 0));
#endif

#if 0
  CvArr *im = cvLoadImage("checker77.png");
  CvPoint2D32f corners[49];
  int count;
  cvFindChessboardCorners(im, cvSize(7,7), corners, &count, 0);
  printf("count=%d\n", count);
#endif

#if 0
  CvMat *src = cvCreateMat(512, 512, CV_8UC3);
  CvMat *dst = cvCreateMat(512, 512, CV_8UC3);
  cvPyrMeanShiftFiltering(src, dst, 5, 5);
  return FROM_CvMat(src);
#endif

  return PyFloat_FromDouble(0.0);
}

static PyObject *pycvFindChessboardCorners(PyObject *self, PyObject *args, PyObject *kw)
{
  CvArr* image;
  PyObject *pyobj_image = NULL;
  CvSize pattern_size;
  PyObject *pyobj_pattern_size = NULL;
  cvpoint2d32f_count corners;
  int flags = CV_CALIB_CB_ADAPTIVE_THRESH;

  const char *keywords[] = { "image", "pattern_size", "flags", NULL };
  if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|i", (char**)keywords, &pyobj_image, &pyobj_pattern_size, &flags))
    return NULL;
  if (!convert_to_CvArr(pyobj_image, &image, "image")) return NULL;
  if (!convert_to_CvSize(pyobj_pattern_size, &pattern_size, "pattern_size")) return NULL;
  int r;
  corners.points = new CvPoint2D32f[pattern_size.width * pattern_size.height];
  ERRWRAP(r = cvFindChessboardCorners(image, pattern_size, corners.points,&corners.count, flags));
  return Py_BuildValue("NN", FROM_int(r), FROM_cvpoint2d32f_count(corners));
}

// For functions GetSubRect, GetRow, GetCol.
// recipient has a view into donor's data, and needs to share it.
// make recipient use the donor's data, compute the offset,
// and manage reference counts.

static void preShareData(CvArr *donor, CvMat **recipient)
{
  *recipient = cvCreateMatHeader(4, 4, cvGetElemType(donor));
}

static PyObject *shareData(PyObject *donor, CvArr *pdonor, CvMat *precipient)
{
  PyObject *recipient = (PyObject*)PyObject_NEW(cvmat_t, &cvmat_Type);
  ((cvmat_t*)recipient)->a = precipient;
  ((cvmat_t*)recipient)->offset = cvPtr1D(precipient, 0) - cvPtr1D(pdonor, 0);

  PyObject *arr_data;
  if (is_cvmat(donor)) {
    arr_data = ((cvmat_t*)donor)->data;
    ((cvmat_t*)recipient)->offset += ((cvmat_t*)donor)->offset;
  } else if (is_iplimage(donor)) {
    arr_data = ((iplimage_t*)donor)->data;
    ((cvmat_t*)recipient)->offset += ((iplimage_t*)donor)->offset;
  } else {
    return (PyObject*)failmsg("Argument 'mat' must be either IplImage or CvMat");
  }
  ((cvmat_t*)recipient)->data = arr_data;
  Py_INCREF(arr_data);
  return recipient;
}

static PyObject *shareDataND(PyObject *donor, CvMatND *pdonor, CvMatND *precipient)
{
  PyObject *recipient = (PyObject*)PyObject_NEW(cvmatnd_t, &cvmatnd_Type);
  ((cvmatnd_t*)recipient)->a = precipient;
  ((cvmatnd_t*)recipient)->offset = 0;

  PyObject *arr_data;
  arr_data = ((cvmatnd_t*)donor)->data;
  ((cvmatnd_t*)recipient)->data = arr_data;
  Py_INCREF(arr_data);
  return recipient;
}

static PyObject *pycvGetHuMoments(PyObject *self, PyObject *args)
{
  CvMoments* moments;
  PyObject *pyobj_moments = NULL;

  if (!PyArg_ParseTuple(args, "O", &pyobj_moments))
    return NULL;
  if (!convert_to_CvMomentsPTR(pyobj_moments, &moments, "moments")) return NULL;
  CvHuMoments r;
  ERRWRAP(cvGetHuMoments(moments, &r));
  return Py_BuildValue("ddddddd", r.hu1, r.hu2, r.hu3, r.hu4, r.hu5, r.hu6, r.hu7);
}

static PyObject *pycvFitLine(PyObject *self, PyObject *args)
{
  cvarrseq points;
  PyObject *pyobj_points = NULL;
  int dist_type;
  float param;
  float reps;
  float aeps;
  float r[6];

  if (!PyArg_ParseTuple(args, "Oifff", &pyobj_points, &dist_type, &param, &reps, &aeps))
    return NULL;
  if (!convert_to_cvarrseq(pyobj_points, &points, "points")) return NULL;
  ERRWRAP(cvFitLine(points.mat, dist_type, param, reps, aeps, r));
  int dimension;
  if (strcmp("opencv-matrix", cvTypeOf(points.mat)->type_name) == 0)
    dimension = CV_MAT_CN(cvGetElemType(points.mat));
  else {
    // sequence case... don't think there is a sequence of 3d points,
    // so assume 2D
    dimension = 2;
  }
  if (dimension == 2)
    return Py_BuildValue("dddd", r[0], r[1], r[2], r[3]);
  else
    return Py_BuildValue("dddddd", r[0], r[1], r[2], r[3], r[4], r[5]);
}

static PyObject *pycvGetMinMaxHistValue(PyObject *self, PyObject *args)
{
  CvHistogram* hist;
  PyObject *pyobj_hist = NULL;
  float min_val;
  float max_val;
  int min_loc[CV_MAX_DIM];
  int max_loc[CV_MAX_DIM];

  if (!PyArg_ParseTuple(args, "O", &pyobj_hist))
    return NULL;
  if (!convert_to_CvHistogram(pyobj_hist, &hist, "hist")) return NULL;
  ERRWRAP(cvGetMinMaxHistValue(hist, &min_val, &max_val, min_loc, max_loc));
  int d = cvGetDims(hist->bins);
  PyObject *pminloc = PyTuple_New(d), *pmaxloc = PyTuple_New(d);
  for (int i = 0; i < d; i++) {
    PyTuple_SetItem(pminloc, i, PyInt_FromLong(min_loc[i]));
    PyTuple_SetItem(pmaxloc, i, PyInt_FromLong(max_loc[i]));
  }
  return Py_BuildValue("ffNN", min_val, max_val, pminloc, pmaxloc);
}

static CvSeq* cvHOGDetectMultiScale( const CvArr* image, CvMemStorage* storage,
  const CvArr* svm_classifier=NULL, CvSize win_stride=cvSize(0,0),
  double hit_threshold=0, double scale=1.05,
  int group_threshold=2, CvSize padding=cvSize(0,0),
  CvSize win_size=cvSize(64,128), CvSize block_size=cvSize(16,16),
  CvSize block_stride=cvSize(8,8), CvSize cell_size=cvSize(8,8),
  int nbins=9, int gammaCorrection=1 )
{
    cv::HOGDescriptor hog(win_size, block_size, block_stride, cell_size, nbins, 1, -1, cv::HOGDescriptor::L2Hys, 0.2, gammaCorrection!=0);
    if(win_stride.width == 0 && win_stride.height == 0)
        win_stride = block_stride;
    cv::Mat img = cv::cvarrToMat(image);
    std::vector<cv::Rect> found;
    if(svm_classifier)
    {
        CvMat stub, *m = cvGetMat(svm_classifier, &stub);
        int sz = m->cols*m->rows;
        CV_Assert(CV_IS_MAT_CONT(m->type) && (m->cols == 1 || m->rows == 1) && CV_MAT_TYPE(m->type) == CV_32FC1);
        std::vector<float> w(sz);
        std::copy(m->data.fl, m->data.fl + sz, w.begin());
        hog.setSVMDetector(w);
    }
    else
        hog.setSVMDetector(cv::HOGDescriptor::getDefaultPeopleDetector());
    hog.detectMultiScale(img, found, hit_threshold, win_stride, padding, scale, group_threshold);
    CvSeq* seq = cvCreateSeq(cv::DataType<cv::Rect>::type, sizeof(CvSeq), sizeof(cv::Rect), storage);
    if(found.size())
        cvSeqPushMulti(seq, &found[0], (int)found.size());
    return seq;
}

static int zero = 0;

/************************************************************************/
/* Custom Validators */

#define CVPY_VALIDATE_DrawChessboardCorners() do { \
  if ((patternSize.width * patternSize.height) != corners.count) \
    return (PyObject*)failmsg("Size is %dx%d, but corner list is length %d", patternSize.width, patternSize.height, corners.count); \
  } while (0)

#define cvGetRotationMatrix2D cv2DRotationMatrix

/************************************************************************/
/* Generated functions */

#define constCvMat const CvMat
#define FROM_constCvMatPTR(x) FROM_CvMatPTR((CvMat*)x)

#define cvSnakeImage(image, points, length, a, b, g, win, criteria, calc_gradient) \
  do { \
    int coeff_usage; \
    if ((alpha.count == 1) && (beta.count == 1) && (gamma.count == 1)) \
      coeff_usage = CV_VALUE; \
    else if ((length == alpha.count) && (alpha.count == beta.count) && (beta.count == gamma.count)) \
      coeff_usage = CV_ARRAY; \
    else \
      return (PyObject*)failmsg("SnakeImage weights invalid"); \
    cvSnakeImage(image, points, length, a, b, g, coeff_usage, win, criteria, calc_gradient); \
  } while (0)

#include "generated0.i"

static PyMethodDef methods[] = {

#if PYTHON_USE_NUMPY
  {"fromarray", (PyCFunction)pycvfromarray, METH_KEYWORDS, "fromarray(array) -> cvmatnd"},
#endif

  //{"CalcOpticalFlowFarneback", (PyCFunction)pycvCalcOpticalFlowFarneback, METH_KEYWORDS, "CalcOpticalFlowFarneback(prev, next, flow, pyr_scale=0.5, levels=3, win_size=15, iterations=3, poly_n=7, poly_sigma=1.5, flags=0) -> None"},
  //{"_HOGComputeDescriptors", (PyCFunction)pycvHOGComputeDescriptors, METH_KEYWORDS, "_HOGComputeDescriptors(image, win_stride=block_stride, locations=None, padding=(0,0), win_size=(64,128), block_size=(16,16), block_stride=(8,8), cell_size=(8,8), nbins=9, gammaCorrection=true) -> list_of_descriptors"},
  //{"_HOGDetect", (PyCFunction)pycvHOGDetect, METH_KEYWORDS, "_HOGDetect(image, svm_classifier, win_stride=block_stride, locations=None, padding=(0,0), win_size=(64,128), block_size=(16,16), block_stride=(8,8), cell_size=(8,8), nbins=9, gammaCorrection=true) -> list_of_points"},
  //{"_HOGDetectMultiScale", (PyCFunction)pycvHOGDetectMultiScale, METH_KEYWORDS, "_HOGDetectMultiScale(image, svm_classifier, win_stride=block_stride, scale=1.05, group_threshold=2, padding=(0,0), win_size=(64,128), block_size=(16,16), block_stride=(8,8), cell_size=(8,8), nbins=9, gammaCorrection=true) -> list_of_points"},

  {"temp_test", temp_test, METH_VARARGS},

#include "generated1.i"

  {NULL, NULL},
};

/************************************************************************/
/* Module init */

static int to_ok(PyTypeObject *to)
{
  to->tp_alloc = PyType_GenericAlloc;
  to->tp_new = PyType_GenericNew;
  to->tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE;
  return (PyType_Ready(to) == 0);
}

#define MKTYPE(NAME)  do { NAME##_specials(); if (!to_ok(&NAME##_Type)) return; } while (0)

extern "C"
#if defined WIN32 || defined _WIN32
__declspec(dllexport)
#endif
void initcv()
{
  PyObject *m, *d;

  cvSetErrMode(CV_ErrModeParent);

  MKTYPE(cvcontourtree);
  MKTYPE(cvfont);
  MKTYPE(cvhistogram);
  MKTYPE(cvlineiterator);
  MKTYPE(cvmat);
  MKTYPE(cvmatnd);
  MKTYPE(cvmemstorage);
  MKTYPE(cvsubdiv2dedge);
  MKTYPE(cvrng);
  MKTYPE(cvseq);
  MKTYPE(cvset);
  MKTYPE(cvsubdiv2d);
  MKTYPE(cvsubdiv2dpoint);
  MKTYPE(iplimage);
  MKTYPE(memtrack);

#include "generated4.i"

  m = Py_InitModule(MODULESTR"", methods);
  d = PyModule_GetDict(m);

  PyDict_SetItemString(d, "__version__", PyString_FromString("$Rev: 3057 $"));

  opencv_error = PyErr_NewException((char*)MODULESTR".error", NULL, NULL);
  PyDict_SetItemString(d, "error", opencv_error);

  // Couple of warnings about strict aliasing here.  Not clear how to fix.
  union {
    PyObject *o;
    PyTypeObject *to;
  } convert;
  convert.to = &iplimage_Type;
  PyDict_SetItemString(d, "iplimage", convert.o);
  convert.to = &cvmat_Type;
  PyDict_SetItemString(d, "cvmat", convert.o);

#define PUBLISH(I) PyDict_SetItemString(d, #I, PyInt_FromLong(I))
#define PUBLISHU(I) PyDict_SetItemString(d, #I, PyLong_FromUnsignedLong(I))

  PUBLISHU(IPL_DEPTH_8U);
  PUBLISHU(IPL_DEPTH_8S);
  PUBLISHU(IPL_DEPTH_16U);
  PUBLISHU(IPL_DEPTH_16S);
  PUBLISHU(IPL_DEPTH_32S);
  PUBLISHU(IPL_DEPTH_32F);
  PUBLISHU(IPL_DEPTH_64F);

  PUBLISH(CV_LOAD_IMAGE_COLOR);
  PUBLISH(CV_LOAD_IMAGE_GRAYSCALE);
  PUBLISH(CV_LOAD_IMAGE_UNCHANGED);
  PUBLISH(CV_HIST_ARRAY);
  PUBLISH(CV_HIST_SPARSE);
  PUBLISH(CV_8U);
  PUBLISH(CV_8UC1);
  PUBLISH(CV_8UC2);
  PUBLISH(CV_8UC3);
  PUBLISH(CV_8UC4);
  PUBLISH(CV_8S);
  PUBLISH(CV_8SC1);
  PUBLISH(CV_8SC2);
  PUBLISH(CV_8SC3);
  PUBLISH(CV_8SC4);
  PUBLISH(CV_16U);
  PUBLISH(CV_16UC1);
  PUBLISH(CV_16UC2);
  PUBLISH(CV_16UC3);
  PUBLISH(CV_16UC4);
  PUBLISH(CV_16S);
  PUBLISH(CV_16SC1);
  PUBLISH(CV_16SC2);
  PUBLISH(CV_16SC3);
  PUBLISH(CV_16SC4);
  PUBLISH(CV_32S);
  PUBLISH(CV_32SC1);
  PUBLISH(CV_32SC2);
  PUBLISH(CV_32SC3);
  PUBLISH(CV_32SC4);
  PUBLISH(CV_32F);
  PUBLISH(CV_32FC1);
  PUBLISH(CV_32FC2);
  PUBLISH(CV_32FC3);
  PUBLISH(CV_32FC4);
  PUBLISH(CV_64F);
  PUBLISH(CV_64FC1);
  PUBLISH(CV_64FC2);
  PUBLISH(CV_64FC3);
  PUBLISH(CV_64FC4);
  PUBLISH(CV_NEXT_AROUND_ORG);
  PUBLISH(CV_NEXT_AROUND_DST);
  PUBLISH(CV_PREV_AROUND_ORG);
  PUBLISH(CV_PREV_AROUND_DST);
  PUBLISH(CV_NEXT_AROUND_LEFT);
  PUBLISH(CV_NEXT_AROUND_RIGHT);
  PUBLISH(CV_PREV_AROUND_LEFT);
  PUBLISH(CV_PREV_AROUND_RIGHT);

  PUBLISH(CV_WINDOW_AUTOSIZE);

  PUBLISH(CV_PTLOC_INSIDE);
  PUBLISH(CV_PTLOC_ON_EDGE);
  PUBLISH(CV_PTLOC_VERTEX);
  PUBLISH(CV_PTLOC_OUTSIDE_RECT);

#include "generated2.i"

#if 0
  {
    int sizes[] = { 10 } ;
    float ranges[] = { 0.0, 1.0 };
    // CvHistogram*h = cvCreateHist(1, sizes, CV_HIST_ARRAY);
    CvHistogram H;
    float data[10];
    CvHistogram*h = cvMakeHistHeaderForArray(1, sizes, &H, data);
    printf("h->type = %08x\n", h->type);
    printf("h->bins = %p\n", h->bins);
    printf("h->mat = %p\n", &(h->mat));
  }
#endif
}