cv::Mat Histogram1D::stretch(const cv::Mat &image, int minValue){
cv::MatND hist = getHistogram(image);
int imin = 0;
for( ; imin < m_histSize[0]; imin++){
//std::cout << hist.at<float>(imin) << std::endl;
if( hist.at<float>(imin) > minValue )
break;
}
int imax = m_histSize[0] - 1;
for( ; imax >= 0; imax-- ){
if(hist.at<float>(imax) > minValue )
break;
}
int dim(256);
cv::Mat lookup(1,
&dim,
CV_8U
);
for(int i = 0; i < 256; i++){
if( i < imin ) lookup.at<uchar>(i) = 0;
else if ( i > imax ) lookup.at<uchar>(i) = 255;
else lookup.at<uchar>(i) = static_cast<uchar>(
255.0*(i - imin)/ (imax-imin) + 0.5);
}
cv::Mat result;
result = applyLookUp(image, lookup);
return result;
}
cv::Mat Processor::invertColors(const cv::Mat& image){
int dim(256);
cv::Mat lut( 1 , &dim , CV_8U);
for ( int i = 0 ; i < 256 ; i++ )
lut.at<uchar>(i) = 255 - i;
return applyLookUp(image , lut);
}
//--------------------------------------------------------------------------------------------------
//
cv::Mat
Histogram1D::stretch( const cv::Mat& image, int32_t minValue )
{
// Compute histogram first
cv::MatND hist = getHistogram( image );
// find left extremity of the histogram
int imin = 0;
for( ; imin < histSize_[0]; imin++ )
{
std::cout << hist.at< float >( imin ) << std::endl;
if( hist.at< float >( imin ) > minValue )
{
break;
}
}
// find right extremity of the histogram
int imax = histSize_[0] - 1;
for( ; imax >= 0; imax-- )
{
if( hist.at< float >( imax ) > minValue )
{
break;
}
}
// Create lookup table
int dims[1] = { 256 };
cv::MatND lookup( 1, dims, CV_8U );
for( int i = 0; i < 256; ++i )
{
if( i < imin )
{
lookup.at< uchar >( i ) = 0;
}
else if( i > imax )
{
lookup.at< uchar >( i ) = 255;
}
else
{
lookup.at< uchar >( i ) = static_cast<uchar>( 255.0 * (i - imin) /
(imax - imin) + 0.5 );
}
}
// Apply lookup table
cv::Mat result;
result = applyLookUp( image, lookup );
return result;
}
