fixed invalid output of cv::dft when using DFT_ROWS + DFT_COMPLEX_OUTPUT (http://code.opencv.org/issues/3428)

This commit is contained in:
Vadim Pisarevsky 2015-04-29 23:08:22 +03:00
parent 7918267d02
commit 74e2b8cbcb
2 changed files with 67 additions and 36 deletions

View File

@ -60,7 +60,6 @@ namespace cv
#undef USE_IPP_DFT
#endif
/****************************************************************************************\
Discrete Fourier Transform
\****************************************************************************************/
@ -2426,6 +2425,47 @@ static bool ocl_dft_amdfft(InputArray _src, OutputArray _dst, int flags)
#endif // HAVE_CLAMDFFT
namespace cv
{
static void complementComplexOutput(Mat& dst, int len, int dft_dims)
{
int i, n = dst.cols;
size_t elem_size = dst.elemSize1();
if( elem_size == sizeof(float) )
{
float* p0 = dst.ptr<float>();
size_t dstep = dst.step/sizeof(p0[0]);
for( i = 0; i < len; i++ )
{
float* p = p0 + dstep*i;
float* q = dft_dims == 1 || i == 0 || i*2 == len ? p : p0 + dstep*(len-i);
for( int j = 1; j < (n+1)/2; j++ )
{
p[(n-j)*2] = q[j*2];
p[(n-j)*2+1] = -q[j*2+1];
}
}
}
else
{
double* p0 = dst.ptr<double>();
size_t dstep = dst.step/sizeof(p0[0]);
for( i = 0; i < len; i++ )
{
double* p = p0 + dstep*i;
double* q = dft_dims == 1 || i == 0 || i*2 == len ? p : p0 + dstep*(len-i);
for( int j = 1; j < (n+1)/2; j++ )
{
p[(n-j)*2] = q[j*2];
p[(n-j)*2+1] = -q[j*2+1];
}
}
}
}
}
void cv::dft( InputArray _src0, OutputArray _dst, int flags, int nonzero_rows )
{
#ifdef HAVE_CLAMDFFT
@ -2705,7 +2745,11 @@ void cv::dft( InputArray _src0, OutputArray _dst, int flags, int nonzero_rows )
}
if( stage != 1 )
{
if( !inv && real_transform && dst.channels() == 2 )
complementComplexOutput(dst, nonzero_rows, 1);
break;
}
src = dst;
}
else
@ -2847,41 +2891,7 @@ void cv::dft( InputArray _src0, OutputArray _dst, int flags, int nonzero_rows )
if( stage != 0 )
{
if( !inv && real_transform && dst.channels() == 2 && len > 1 )
{
int n = dst.cols;
if( elem_size == (int)sizeof(float) )
{
float* p0 = dst.ptr<float>();
size_t dstep = dst.step/sizeof(p0[0]);
for( i = 0; i < len; i++ )
{
float* p = p0 + dstep*i;
float* q = i == 0 || i*2 == len ? p : p0 + dstep*(len-i);
for( int j = 1; j < (n+1)/2; j++ )
{
p[(n-j)*2] = q[j*2];
p[(n-j)*2+1] = -q[j*2+1];
}
}
}
else
{
double* p0 = dst.ptr<double>();
size_t dstep = dst.step/sizeof(p0[0]);
for( i = 0; i < len; i++ )
{
double* p = p0 + dstep*i;
double* q = i == 0 || i*2 == len ? p : p0 + dstep*(len-i);
for( int j = 1; j < (n+1)/2; j++ )
{
p[(n-j)*2] = q[j*2];
p[(n-j)*2+1] = -q[j*2+1];
}
}
}
}
complementComplexOutput(dst, len, 2);
break;
}
src = dst;

View File

@ -866,3 +866,24 @@ protected:
};
TEST(Core_DFT, complex_output) { Core_DFTComplexOutputTest test; test.safe_run(); }
TEST(Core_DFT, complex_output2)
{
for( int i = 0; i < 100; i++ )
{
int type = theRNG().uniform(0, 2) ? CV_64F : CV_32F;
int m = theRNG().uniform(1, 10);
int n = theRNG().uniform(1, 10);
Mat x(m, n, type), out;
randu(x, -1., 1.);
dft(x, out, DFT_ROWS | DFT_COMPLEX_OUTPUT);
double nrm = norm(out, NORM_INF);
double thresh = n*m*2;
if( nrm > thresh )
{
cout << "x: " << x << endl;
cout << "out: " << out << endl;
ASSERT_LT(nrm, thresh);
}
}
}