/*M/////////////////////////////////////////////////////////////////////////////////////// // // IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING. // // By downloading, copying, installing or using the software you agree to this license. // If you do not agree to this license, do not download, install, // copy or use the software. // // // Intel License Agreement // For Open Source Computer Vision Library // // Copyright (C) 2000, Intel Corporation, all rights reserved. // Third party copyrights are property of their respective owners. // // Redistribution and use in source and binary forms, with or without modification, // are permitted provided that the following conditions are met: // // * Redistribution's of source code must retain the above copyright notice, // this list of conditions and the following disclaimer. // // * Redistribution's in binary form must reproduce the above copyright notice, // this list of conditions and the following disclaimer in the documentation // and/or other materials provided with the distribution. // // * The name of Intel Corporation may not be used to endorse or promote products // derived from this software without specific prior written permission. // // This software is provided by the copyright holders and contributors "as is" and // any express or implied warranties, including, but not limited to, the implied // warranties of merchantability and fitness for a particular purpose are disclaimed. // In no event shall the Intel Corporation or contributors be liable for any direct, // indirect, incidental, special, exemplary, or consequential damages // (including, but not limited to, procurement of substitute goods or services; // loss of use, data, or profits; or business interruption) however caused // and on any theory of liability, whether in contract, strict liability, // or tort (including negligence or otherwise) arising in any way out of // the use of this software, even if advised of the possibility of such damage. // //M*/ #include "precomp.hpp" static int icvSklansky_32s( CvPoint** array, int start, int end, int* stack, int nsign, int sign2 ) { int incr = end > start ? 1 : -1; /* prepare first triangle */ int pprev = start, pcur = pprev + incr, pnext = pcur + incr; int stacksize = 3; if( start == end || (array[start]->x == array[end]->x && array[start]->y == array[end]->y) ) { stack[0] = start; return 1; } stack[0] = pprev; stack[1] = pcur; stack[2] = pnext; end += incr; /* make end = afterend */ while( pnext != end ) { /* check the angle p1,p2,p3 */ int cury = array[pcur]->y; int nexty = array[pnext]->y; int by = nexty - cury; if( CV_SIGN(by) != nsign ) { int ax = array[pcur]->x - array[pprev]->x; int bx = array[pnext]->x - array[pcur]->x; int ay = cury - array[pprev]->y; int convexity = ay*bx - ax*by;/* if >0 then convex angle */ if( CV_SIGN(convexity) == sign2 && (ax != 0 || ay != 0) ) { pprev = pcur; pcur = pnext; pnext += incr; stack[stacksize] = pnext; stacksize++; } else { if( pprev == start ) { pcur = pnext; stack[1] = pcur; pnext += incr; stack[2] = pnext; } else { stack[stacksize-2] = pnext; pcur = pprev; pprev = stack[stacksize-4]; stacksize--; } } } else { pnext += incr; stack[stacksize-1] = pnext; } } return --stacksize; } static int icvSklansky_32f( CvPoint2D32f** array, int start, int end, int* stack, int nsign, int sign2 ) { int incr = end > start ? 1 : -1; /* prepare first triangle */ int pprev = start, pcur = pprev + incr, pnext = pcur + incr; int stacksize = 3; if( start == end || (array[start]->x == array[end]->x && array[start]->y == array[end]->y) ) { stack[0] = start; return 1; } stack[0] = pprev; stack[1] = pcur; stack[2] = pnext; end += incr; /* make end = afterend */ while( pnext != end ) { /* check the angle p1,p2,p3 */ float cury = array[pcur]->y; float nexty = array[pnext]->y; float by = nexty - cury; if( CV_SIGN( by ) != nsign ) { float ax = array[pcur]->x - array[pprev]->x; float bx = array[pnext]->x - array[pcur]->x; float ay = cury - array[pprev]->y; float convexity = ay*bx - ax*by;/* if >0 then convex angle */ if( CV_SIGN( convexity ) == sign2 && (ax != 0 || ay != 0) ) { pprev = pcur; pcur = pnext; pnext += incr; stack[stacksize] = pnext; stacksize++; } else { if( pprev == start ) { pcur = pnext; stack[1] = pcur; pnext += incr; stack[2] = pnext; } else { stack[stacksize-2] = pnext; pcur = pprev; pprev = stack[stacksize-4]; stacksize--; } } } else { pnext += incr; stack[stacksize-1] = pnext; } } return --stacksize; } typedef int (*sklansky_func)( CvPoint** points, int start, int end, int* stack, int sign, int sign2 ); #define cmp_pts( pt1, pt2 ) \ ((pt1)->x < (pt2)->x || ((pt1)->x <= (pt2)->x && (pt1)->y < (pt2)->y)) static CV_IMPLEMENT_QSORT( icvSortPointsByPointers_32s, CvPoint*, cmp_pts ) static CV_IMPLEMENT_QSORT( icvSortPointsByPointers_32f, CvPoint2D32f*, cmp_pts ) static void icvCalcAndWritePtIndices( CvPoint** pointer, int* stack, int start, int end, CvSeq* ptseq, CvSeqWriter* writer ) { int i, incr = start < end ? 1 : -1; int idx, first_idx = ptseq->first->start_index; for( i = start; i != end; i += incr ) { CvPoint* ptr = (CvPoint*)pointer[stack[i]]; CvSeqBlock* block = ptseq->first; while( (unsigned)(idx = (int)(ptr - (CvPoint*)block->data)) >= (unsigned)block->count ) { block = block->next; if( block == ptseq->first ) CV_Error( CV_StsError, "Internal error" ); } idx += block->start_index - first_idx; CV_WRITE_SEQ_ELEM( idx, *writer ); } } CV_IMPL CvSeq* cvConvexHull2( const CvArr* array, void* hull_storage, int orientation, int return_points ) { union { CvContour* c; CvSeq* s; } hull; cv::AutoBuffer _pointer; CvPoint** pointer; CvPoint2D32f** pointerf = 0; cv::AutoBuffer _stack; int* stack; hull.s = 0; CvMat* mat = 0; CvSeqReader reader; CvSeqWriter writer; CvContour contour_header; union { CvContour c; CvSeq s; } hull_header; CvSeqBlock block, hullblock; CvSeq* ptseq = 0; CvSeq* hullseq = 0; int is_float; int* t_stack; int t_count; int i, miny_ind = 0, maxy_ind = 0, total; int hulltype; int stop_idx; sklansky_func sklansky; if( CV_IS_SEQ( array )) { ptseq = (CvSeq*)array; if( !CV_IS_SEQ_POINT_SET( ptseq )) CV_Error( CV_StsBadArg, "Unsupported sequence type" ); if( hull_storage == 0 ) hull_storage = ptseq->storage; } else { ptseq = cvPointSeqFromMat( CV_SEQ_KIND_GENERIC, array, &contour_header, &block ); } if( CV_IS_STORAGE( hull_storage )) { if( return_points ) { hullseq = cvCreateSeq( CV_SEQ_KIND_CURVE|CV_SEQ_ELTYPE(ptseq)| CV_SEQ_FLAG_CLOSED|CV_SEQ_FLAG_CONVEX, sizeof(CvContour), sizeof(CvPoint),(CvMemStorage*)hull_storage ); } else { hullseq = cvCreateSeq( CV_SEQ_KIND_CURVE|CV_SEQ_ELTYPE_PPOINT| CV_SEQ_FLAG_CLOSED|CV_SEQ_FLAG_CONVEX, sizeof(CvContour), sizeof(CvPoint*), (CvMemStorage*)hull_storage ); } } else { if( !CV_IS_MAT( hull_storage )) CV_Error(CV_StsBadArg, "Destination must be valid memory storage or matrix"); mat = (CvMat*)hull_storage; if( (mat->cols != 1 && mat->rows != 1) || !CV_IS_MAT_CONT(mat->type)) CV_Error( CV_StsBadArg, "The hull matrix should be continuous and have a single row or a single column" ); if( mat->cols + mat->rows - 1 < ptseq->total ) CV_Error( CV_StsBadSize, "The hull matrix size might be not enough to fit the hull" ); if( CV_MAT_TYPE(mat->type) != CV_SEQ_ELTYPE(ptseq) && CV_MAT_TYPE(mat->type) != CV_32SC1 ) CV_Error( CV_StsUnsupportedFormat, "The hull matrix must have the same type as input or 32sC1 (integers)" ); hullseq = cvMakeSeqHeaderForArray( CV_SEQ_KIND_CURVE|CV_MAT_TYPE(mat->type)|CV_SEQ_FLAG_CLOSED, sizeof(contour_header), CV_ELEM_SIZE(mat->type), mat->data.ptr, mat->cols + mat->rows - 1, &hull_header.s, &hullblock ); cvClearSeq( hullseq ); } total = ptseq->total; if( total == 0 ) { if( mat ) CV_Error( CV_StsBadSize, "Point sequence can not be empty if the output is matrix" ); return hull.s; } cvStartAppendToSeq( hullseq, &writer ); is_float = CV_SEQ_ELTYPE(ptseq) == CV_32FC2; hulltype = CV_SEQ_ELTYPE(hullseq); sklansky = !is_float ? (sklansky_func)icvSklansky_32s : (sklansky_func)icvSklansky_32f; _pointer.allocate( ptseq->total ); _stack.allocate( ptseq->total + 2); pointer = _pointer; pointerf = (CvPoint2D32f**)pointer; stack = _stack; cvStartReadSeq( ptseq, &reader ); for( i = 0; i < total; i++ ) { pointer[i] = (CvPoint*)reader.ptr; CV_NEXT_SEQ_ELEM( ptseq->elem_size, reader ); } // sort the point set by x-coordinate, find min and max y if( !is_float ) { icvSortPointsByPointers_32s( pointer, total, 0 ); for( i = 1; i < total; i++ ) { int y = pointer[i]->y; if( pointer[miny_ind]->y > y ) miny_ind = i; if( pointer[maxy_ind]->y < y ) maxy_ind = i; } } else { icvSortPointsByPointers_32f( pointerf, total, 0 ); for( i = 1; i < total; i++ ) { float y = pointerf[i]->y; if( pointerf[miny_ind]->y > y ) miny_ind = i; if( pointerf[maxy_ind]->y < y ) maxy_ind = i; } } if( pointer[0]->x == pointer[total-1]->x && pointer[0]->y == pointer[total-1]->y ) { if( hulltype == CV_SEQ_ELTYPE_PPOINT ) { CV_WRITE_SEQ_ELEM( pointer[0], writer ); } else if( hulltype == CV_SEQ_ELTYPE_INDEX ) { int index = 0; CV_WRITE_SEQ_ELEM( index, writer ); } else { CvPoint pt = pointer[0][0]; CV_WRITE_SEQ_ELEM( pt, writer ); } goto finish_hull; } /*upper half */ { int *tl_stack = stack; int tl_count = sklansky( pointer, 0, maxy_ind, tl_stack, -1, 1 ); int *tr_stack = tl_stack + tl_count; int tr_count = sklansky( pointer, ptseq->total - 1, maxy_ind, tr_stack, -1, -1 ); /* gather upper part of convex hull to output */ if( orientation == CV_COUNTER_CLOCKWISE ) { CV_SWAP( tl_stack, tr_stack, t_stack ); CV_SWAP( tl_count, tr_count, t_count ); } if( hulltype == CV_SEQ_ELTYPE_PPOINT ) { for( i = 0; i < tl_count - 1; i++ ) CV_WRITE_SEQ_ELEM( pointer[tl_stack[i]], writer ); for( i = tr_count - 1; i > 0; i-- ) CV_WRITE_SEQ_ELEM( pointer[tr_stack[i]], writer ); } else if( hulltype == CV_SEQ_ELTYPE_INDEX ) { icvCalcAndWritePtIndices( pointer, tl_stack, 0, tl_count-1, ptseq, &writer ); icvCalcAndWritePtIndices( pointer, tr_stack, tr_count-1, 0, ptseq, &writer ); } else { for( i = 0; i < tl_count - 1; i++ ) CV_WRITE_SEQ_ELEM( pointer[tl_stack[i]][0], writer ); for( i = tr_count - 1; i > 0; i-- ) CV_WRITE_SEQ_ELEM( pointer[tr_stack[i]][0], writer ); } stop_idx = tr_count > 2 ? tr_stack[1] : tl_count > 2 ? tl_stack[tl_count - 2] : -1; } /* lower half */ { int *bl_stack = stack; int bl_count = sklansky( pointer, 0, miny_ind, bl_stack, 1, -1 ); int *br_stack = stack + bl_count; int br_count = sklansky( pointer, ptseq->total - 1, miny_ind, br_stack, 1, 1 ); if( orientation != CV_COUNTER_CLOCKWISE ) { CV_SWAP( bl_stack, br_stack, t_stack ); CV_SWAP( bl_count, br_count, t_count ); } if( stop_idx >= 0 ) { int check_idx = bl_count > 2 ? bl_stack[1] : bl_count + br_count > 2 ? br_stack[2-bl_count] : -1; if( check_idx == stop_idx || (check_idx >= 0 && pointer[check_idx]->x == pointer[stop_idx]->x && pointer[check_idx]->y == pointer[stop_idx]->y) ) { /* if all the points lie on the same line, then the bottom part of the convex hull is the mirrored top part (except the exteme points).*/ bl_count = MIN( bl_count, 2 ); br_count = MIN( br_count, 2 ); } } if( hulltype == CV_SEQ_ELTYPE_PPOINT ) { for( i = 0; i < bl_count - 1; i++ ) CV_WRITE_SEQ_ELEM( pointer[bl_stack[i]], writer ); for( i = br_count - 1; i > 0; i-- ) CV_WRITE_SEQ_ELEM( pointer[br_stack[i]], writer ); } else if( hulltype == CV_SEQ_ELTYPE_INDEX ) { icvCalcAndWritePtIndices( pointer, bl_stack, 0, bl_count-1, ptseq, &writer ); icvCalcAndWritePtIndices( pointer, br_stack, br_count-1, 0, ptseq, &writer ); } else { for( i = 0; i < bl_count - 1; i++ ) CV_WRITE_SEQ_ELEM( pointer[bl_stack[i]][0], writer ); for( i = br_count - 1; i > 0; i-- ) CV_WRITE_SEQ_ELEM( pointer[br_stack[i]][0], writer ); } } finish_hull: cvEndWriteSeq( &writer ); if( mat ) { if( mat->rows > mat->cols ) mat->rows = hullseq->total; else mat->cols = hullseq->total; } else { hull.s = hullseq; hull.c->rect = cvBoundingRect( ptseq, ptseq->header_size < (int)sizeof(CvContour) || &ptseq->flags == &contour_header.flags ); /*if( ptseq != (CvSeq*)&contour_header ) hullseq->v_prev = ptseq;*/ } return hull.s; } /* contour must be a simple polygon */ /* it must have more than 3 points */ CV_IMPL CvSeq* cvConvexityDefects( const CvArr* array, const CvArr* hullarray, CvMemStorage* storage ) { CvSeq* defects = 0; int i, index; CvPoint* hull_cur; /* is orientation of hull different from contour one */ int rev_orientation; CvContour contour_header; union { CvContour c; CvSeq s; } hull_header; CvSeqBlock block, hullblock; CvSeq *ptseq = (CvSeq*)array, *hull = (CvSeq*)hullarray; CvSeqReader hull_reader; CvSeqReader ptseq_reader; CvSeqWriter writer; int is_index; if( CV_IS_SEQ( ptseq )) { if( !CV_IS_SEQ_POINT_SET( ptseq )) CV_Error( CV_StsUnsupportedFormat, "Input sequence is not a sequence of points" ); if( !storage ) storage = ptseq->storage; } else { ptseq = cvPointSeqFromMat( CV_SEQ_KIND_GENERIC, array, &contour_header, &block ); } if( CV_SEQ_ELTYPE( ptseq ) != CV_32SC2 ) CV_Error( CV_StsUnsupportedFormat, "Floating-point coordinates are not supported here" ); if( CV_IS_SEQ( hull )) { int hulltype = CV_SEQ_ELTYPE( hull ); if( hulltype != CV_SEQ_ELTYPE_PPOINT && hulltype != CV_SEQ_ELTYPE_INDEX ) CV_Error( CV_StsUnsupportedFormat, "Convex hull must represented as a sequence " "of indices or sequence of pointers" ); if( !storage ) storage = hull->storage; } else { CvMat* mat = (CvMat*)hull; if( !CV_IS_MAT( hull )) CV_Error(CV_StsBadArg, "Convex hull is neither sequence nor matrix"); if( (mat->cols != 1 && mat->rows != 1) || !CV_IS_MAT_CONT(mat->type) || CV_MAT_TYPE(mat->type) != CV_32SC1 ) CV_Error( CV_StsBadArg, "The matrix should be 1-dimensional and continuous array of int's" ); if( mat->cols + mat->rows - 1 > ptseq->total ) CV_Error( CV_StsBadSize, "Convex hull is larger than the point sequence" ); hull = cvMakeSeqHeaderForArray( CV_SEQ_KIND_CURVE|CV_MAT_TYPE(mat->type)|CV_SEQ_FLAG_CLOSED, sizeof(CvContour), CV_ELEM_SIZE(mat->type), mat->data.ptr, mat->cols + mat->rows - 1, &hull_header.s, &hullblock ); } is_index = CV_SEQ_ELTYPE(hull) == CV_SEQ_ELTYPE_INDEX; if( !storage ) CV_Error( CV_StsNullPtr, "NULL storage pointer" ); defects = cvCreateSeq( CV_SEQ_KIND_GENERIC, sizeof(CvSeq), sizeof(CvConvexityDefect), storage ); if( ptseq->total < 4 || hull->total < 3) { //CV_ERROR( CV_StsBadSize, // "point seq size must be >= 4, convex hull size must be >= 3" ); return defects; } /* recognize co-orientation of ptseq and its hull */ { int sign = 0; int index1, index2, index3; if( !is_index ) { CvPoint* pos = *CV_SEQ_ELEM( hull, CvPoint*, 0 ); index1 = cvSeqElemIdx( ptseq, pos ); pos = *CV_SEQ_ELEM( hull, CvPoint*, 1 ); index2 = cvSeqElemIdx( ptseq, pos ); pos = *CV_SEQ_ELEM( hull, CvPoint*, 2 ); index3 = cvSeqElemIdx( ptseq, pos ); } else { index1 = *CV_SEQ_ELEM( hull, int, 0 ); index2 = *CV_SEQ_ELEM( hull, int, 1 ); index3 = *CV_SEQ_ELEM( hull, int, 2 ); } sign += (index2 > index1) ? 1 : 0; sign += (index3 > index2) ? 1 : 0; sign += (index1 > index3) ? 1 : 0; rev_orientation = (sign == 2) ? 0 : 1; } cvStartReadSeq( ptseq, &ptseq_reader, 0 ); cvStartReadSeq( hull, &hull_reader, rev_orientation ); if( !is_index ) { hull_cur = *(CvPoint**)hull_reader.prev_elem; index = cvSeqElemIdx( ptseq, (char*)hull_cur, 0 ); } else { index = *(int*)hull_reader.prev_elem; hull_cur = CV_GET_SEQ_ELEM( CvPoint, ptseq, index ); } cvSetSeqReaderPos( &ptseq_reader, index ); cvStartAppendToSeq( defects, &writer ); /* cycle through ptseq and hull with computing defects */ for( i = 0; i < hull->total; i++ ) { CvConvexityDefect defect; int is_defect = 0; double dx0, dy0; double depth = 0, scale; CvPoint* hull_next; if( !is_index ) hull_next = *(CvPoint**)hull_reader.ptr; else { int t = *(int*)hull_reader.ptr; hull_next = CV_GET_SEQ_ELEM( CvPoint, ptseq, t ); } dx0 = (double)hull_next->x - (double)hull_cur->x; dy0 = (double)hull_next->y - (double)hull_cur->y; assert( dx0 != 0 || dy0 != 0 ); scale = 1./sqrt(dx0*dx0 + dy0*dy0); defect.start = hull_cur; defect.end = hull_next; for(;;) { /* go through ptseq to achieve next hull point */ CV_NEXT_SEQ_ELEM( sizeof(CvPoint), ptseq_reader ); if( ptseq_reader.ptr == (schar*)hull_next ) break; else { CvPoint* cur = (CvPoint*)ptseq_reader.ptr; /* compute distance from current point to hull edge */ double dx = (double)cur->x - (double)hull_cur->x; double dy = (double)cur->y - (double)hull_cur->y; /* compute depth */ double dist = fabs(-dy0*dx + dx0*dy) * scale; if( dist > depth ) { depth = dist; defect.depth_point = cur; defect.depth = (float)depth; is_defect = 1; } } } if( is_defect ) { CV_WRITE_SEQ_ELEM( defect, writer ); } hull_cur = hull_next; if( rev_orientation ) { CV_PREV_SEQ_ELEM( hull->elem_size, hull_reader ); } else { CV_NEXT_SEQ_ELEM( hull->elem_size, hull_reader ); } } return cvEndWriteSeq( &writer ); } CV_IMPL int cvCheckContourConvexity( const CvArr* array ) { int flag = -1; int i; int orientation = 0; CvSeqReader reader; CvContour contour_header; CvSeqBlock block; CvSeq* contour = (CvSeq*)array; if( CV_IS_SEQ(contour) ) { if( !CV_IS_SEQ_POINT_SET(contour)) CV_Error( CV_StsUnsupportedFormat, "Input sequence must be polygon (closed 2d curve)" ); } else { contour = cvPointSeqFromMat(CV_SEQ_KIND_CURVE|CV_SEQ_FLAG_CLOSED, array, &contour_header, &block ); } if( contour->total == 0 ) return -1; cvStartReadSeq( contour, &reader, 0 ); flag = 1; if( CV_SEQ_ELTYPE( contour ) == CV_32SC2 ) { CvPoint *prev_pt = (CvPoint*)reader.prev_elem; CvPoint *cur_pt = (CvPoint*)reader.ptr; int dx0 = cur_pt->x - prev_pt->x; int dy0 = cur_pt->y - prev_pt->y; for( i = 0; i < contour->total; i++ ) { int dxdy0, dydx0; int dx, dy; /*int orient; */ CV_NEXT_SEQ_ELEM( sizeof(CvPoint), reader ); prev_pt = cur_pt; cur_pt = (CvPoint *) reader.ptr; dx = cur_pt->x - prev_pt->x; dy = cur_pt->y - prev_pt->y; dxdy0 = dx * dy0; dydx0 = dy * dx0; /* find orientation */ /*orient = -dy0 * dx + dx0 * dy; orientation |= (orient > 0) ? 1 : 2; */ orientation |= (dydx0 > dxdy0) ? 1 : ((dydx0 < dxdy0) ? 2 : 3); if( orientation == 3 ) { flag = 0; break; } dx0 = dx; dy0 = dy; } } else { CV_Assert( CV_SEQ_ELTYPE(contour) == CV_32FC2 ); CvPoint2D32f *prev_pt = (CvPoint2D32f*)reader.prev_elem; CvPoint2D32f *cur_pt = (CvPoint2D32f*)reader.ptr; float dx0 = cur_pt->x - prev_pt->x; float dy0 = cur_pt->y - prev_pt->y; for( i = 0; i < contour->total; i++ ) { float dxdy0, dydx0; float dx, dy; /*int orient; */ CV_NEXT_SEQ_ELEM( sizeof(CvPoint2D32f), reader ); prev_pt = cur_pt; cur_pt = (CvPoint2D32f*) reader.ptr; dx = cur_pt->x - prev_pt->x; dy = cur_pt->y - prev_pt->y; dxdy0 = dx * dy0; dydx0 = dy * dx0; /* find orientation */ /*orient = -dy0 * dx + dx0 * dy; orientation |= (orient > 0) ? 1 : 2; */ orientation |= (dydx0 > dxdy0) ? 1 : ((dydx0 < dxdy0) ? 2 : 3); if( orientation == 3 ) { flag = 0; break; } dx0 = dx; dy0 = dy; } } return flag; } /* End of file. */