void fft2(Mat_<float> src)
{
int x = getOptimalDFTSize(2* src.rows );
int y = getOptimalDFTSize(2* src.cols );
copyMakeBorder(src, src, 0, (x - src.rows), 0, (y - src.cols), BORDER_CONSTANT, Scalar::all(0));
// Get padded image size
const int wx = src.cols, wy = src.rows;
const int cx = wx/2, cy = wy/2;
//--------------------------------//
// DFT - performing //
cv::Mat_<float> imgs[] = {src.clone(), Mat::zeros(src.size(), CV_32F)};
cv::Mat_<cv::Vec2f> img_dft;
merge(imgs,2,img_dft);
dft(img_dft, img_dft);
split(img_dft,imgs);
cv::Mat_<float> magnitude, phase;
cartToPolar(imgs[0],imgs[1],magnitude,phase);
dftshift(magnitude);
magnitude = magnitude + 1.0f;
log(magnitude,magnitude);
normalize(magnitude,magnitude,0,1,CV_MINMAX);
namedWindow("img_dft",WINDOW_NORMAL);
imshow("img_dft",magnitude);
waitKey(0);
cout << "out" << endl;
}
void opticalFlowMagnitudeAngle(const Mat& flow, Mat& magnitude, Mat& angle) {
if (magnitude.rows != flow.rows || magnitude.cols != flow.cols)
magnitude.create(flow.rows, flow.cols, CV_32FC1);
if (angle.rows != flow.rows || angle.cols != flow.cols)
angle.create(flow.rows, flow.cols, CV_32FC1);
Mat xy[2];
split(flow, xy);
try { cartToPolar(xy[0], xy[1], magnitude, angle, true); }
catch (Exception e) { throwError(e); }
}
void CvHOGEvaluator::integralHistogram( const Mat &img, std::vector<Mat> &histogram, Mat &norm, int nbins ) const
{
CV_Assert( img.type() == CV_8U || img.type() == CV_8UC3 );
int x, y, binIdx;
Size gradSize( img.size() );
Size histSize( histogram[0].size() );
Mat grad( gradSize, CV_32F );
Mat qangle( gradSize, CV_8U );
AutoBuffer<int> mapbuf( gradSize.width + gradSize.height + 4 );
int* xmap = (int*) mapbuf + 1;
int* ymap = xmap + gradSize.width + 2;
const int borderType = (int) BORDER_REPLICATE;
for ( x = -1; x < gradSize.width + 1; x++ )
xmap[x] = borderInterpolate( x, gradSize.width, borderType );
for ( y = -1; y < gradSize.height + 1; y++ )
ymap[y] = borderInterpolate( y, gradSize.height, borderType );
int width = gradSize.width;
AutoBuffer<float> _dbuf( width * 4 );
float* dbuf = _dbuf;
Mat Dx( 1, width, CV_32F, dbuf );
Mat Dy( 1, width, CV_32F, dbuf + width );
Mat Mag( 1, width, CV_32F, dbuf + width * 2 );
Mat Angle( 1, width, CV_32F, dbuf + width * 3 );
float angleScale = (float) ( nbins / CV_PI );
for ( y = 0; y < gradSize.height; y++ )
{
const uchar* currPtr = img.data + img.step * ymap[y];
const uchar* prevPtr = img.data + img.step * ymap[y - 1];
const uchar* nextPtr = img.data + img.step * ymap[y + 1];
float* gradPtr = (float*) grad.ptr( y );
uchar* qanglePtr = (uchar*) qangle.ptr( y );
for ( x = 0; x < width; x++ )
{
dbuf[x] = (float) ( currPtr[xmap[x + 1]] - currPtr[xmap[x - 1]] );
dbuf[width + x] = (float) ( nextPtr[xmap[x]] - prevPtr[xmap[x]] );
}
cartToPolar( Dx, Dy, Mag, Angle, false );
for ( x = 0; x < width; x++ )
{
float mag = dbuf[x + width * 2];
float angle = dbuf[x + width * 3];
angle = angle * angleScale - 0.5f;
int bidx = cvFloor( angle );
angle -= bidx;
if( bidx < 0 )
bidx += nbins;
else if( bidx >= nbins )
bidx -= nbins;
qanglePtr[x] = (uchar) bidx;
gradPtr[x] = mag;
}
}
integral( grad, norm, grad.depth() );
float* histBuf;
const float* magBuf;
const uchar* binsBuf;
int binsStep = (int) ( qangle.step / sizeof(uchar) );
int histStep = (int) ( histogram[0].step / sizeof(float) );
int magStep = (int) ( grad.step / sizeof(float) );
for ( binIdx = 0; binIdx < nbins; binIdx++ )
{
histBuf = (float*) histogram[binIdx].data;
magBuf = (const float*) grad.data;
binsBuf = (const uchar*) qangle.data;
memset( histBuf, 0, histSize.width * sizeof ( histBuf[0] ) );
histBuf += histStep + 1;
for ( y = 0; y < qangle.rows; y++ )
{
histBuf[-1] = 0.f;
float strSum = 0.f;
for ( x = 0; x < qangle.cols; x++ )
{
if( binsBuf[x] == binIdx )
strSum += magBuf[x];
histBuf[x] = histBuf[-histStep + x] + strSum;
}
histBuf += histStep;
binsBuf += binsStep;
magBuf += magStep;
}
}
}
void computeChannels(InputArray image, vector<Mat>& channels)
{
Mat_<float> grad;
Mat_<float> angles;
Mat luv, gray, src;
if(image.getMat().channels() > 1)
{
src = Mat(image.getMat().rows, image.getMat().cols, CV_32FC3);
image.getMat().convertTo(src, CV_32FC3, 1./255);
cvtColor(src, gray, CV_RGB2GRAY);
cvtColor(src, luv, CV_RGB2Luv);
}
else
{
src = Mat(image.getMat().rows, image.getMat().cols, CV_32FC1);
image.getMat().convertTo(src, CV_32FC1, 1./255);
src.copyTo(gray);
}
Mat_<float> row_der, col_der;
Sobel(gray, row_der, CV_32F, 0, 1);
Sobel(gray, col_der, CV_32F, 1, 0);
cartToPolar(col_der, row_der, grad, angles, true);
//magnitude(row_der, col_der, grad);
Mat_<Vec6f> hist = Mat_<Vec6f>::zeros(grad.rows, grad.cols);
//const float to_deg = 180 / 3.1415926f;
for (int row = 0; row < grad.rows; ++row) {
for (int col = 0; col < grad.cols; ++col) {
//float angle = atan2(row_der(row, col), col_der(row, col)) * to_deg;
float angle = angles(row, col);
if (angle < 0)
angle += 180;
int ind = (int)(angle / 30);
// If angle == 180, prevent index overflow
if (ind == 6)
ind = 5;
hist(row, col)[ind] = grad(row, col) * 255;
}
}
channels.clear();
if(image.getMat().channels() > 1)
{
Mat luv_channels[3];
split(luv, luv_channels);
for( int i = 0; i < 3; ++i )
channels.push_back(luv_channels[i]);
}
channels.push_back(grad);
vector<Mat> hist_channels;
split(hist, hist_channels);
for( size_t i = 0; i < hist_channels.size(); ++i )
channels.push_back(hist_channels[i]);
}
