fast-yolo4/3rdparty/opencv/inc/opencv2/quality/qualitypsnr.hpp
2024-09-25 09:43:03 +08:00

120 lines
3.9 KiB
C++

// This file is part of OpenCV project.
// It is subject to the license terms in the LICENSE file found in the top-level directory
// of this distribution and at http://opencv.org/license.html.
#ifndef OPENCV_QUALITY_QUALITYPSNR_HPP
#define OPENCV_QUALITY_QUALITYPSNR_HPP
#include <limits> // numeric_limits
#include "qualitybase.hpp"
#include "qualitymse.hpp"
namespace cv
{
namespace quality
{
/**
@brief Full reference peak signal to noise ratio (PSNR) algorithm https://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio
*/
class CV_EXPORTS_W QualityPSNR
: public QualityBase {
public:
/** @brief Default maximum pixel value */
#if __cplusplus >= 201103L || (defined(_MSC_VER) && _MSC_VER >= 1900/*MSVS 2015*/)
static constexpr double MAX_PIXEL_VALUE_DEFAULT = 255.;
#else
// support MSVS 2013
static const int MAX_PIXEL_VALUE_DEFAULT = 255;
#endif
/**
@brief Create an object which calculates quality
@param ref input image to use as the source for comparison
@param maxPixelValue maximum per-channel value for any individual pixel; eg 255 for uint8 image
*/
CV_WRAP static Ptr<QualityPSNR> create( InputArray ref, double maxPixelValue = QualityPSNR::MAX_PIXEL_VALUE_DEFAULT )
{
return Ptr<QualityPSNR>(new QualityPSNR(QualityMSE::create(ref), maxPixelValue));
}
/**
@brief Compute the PSNR
@param cmp Comparison image
@returns Per-channel PSNR value, or std::numeric_limits<double>::infinity() if the MSE between the two images == 0
*/
CV_WRAP cv::Scalar compute( InputArray cmp ) CV_OVERRIDE
{
auto result = _qualityMSE->compute( cmp );
_qualityMSE->getQualityMap(_qualityMap); // copy from internal obj to this obj
return _mse_to_psnr(
result
, _maxPixelValue
);
}
/** @brief Implements Algorithm::empty() */
CV_WRAP bool empty() const CV_OVERRIDE { return _qualityMSE->empty() && QualityBase::empty(); }
/** @brief Implements Algorithm::clear() */
CV_WRAP void clear() CV_OVERRIDE { _qualityMSE->clear(); QualityBase::clear(); }
/**
@brief static method for computing quality
@param ref reference image
@param cmp comparison image
@param qualityMap output quality map, or cv::noArray()
@param maxPixelValue maximum per-channel value for any individual pixel; eg 255 for uint8 image
@returns PSNR value, or std::numeric_limits<double>::infinity() if the MSE between the two images == 0
*/
CV_WRAP static cv::Scalar compute( InputArray ref, InputArray cmp, OutputArray qualityMap, double maxPixelValue = QualityPSNR::MAX_PIXEL_VALUE_DEFAULT)
{
return _mse_to_psnr(
QualityMSE::compute(ref, cmp, qualityMap)
, maxPixelValue
);
}
/** @brief return the maximum pixel value used for PSNR computation */
CV_WRAP double getMaxPixelValue() const { return _maxPixelValue; }
/**
@brief sets the maximum pixel value used for PSNR computation
@param val Maximum pixel value
*/
CV_WRAP void setMaxPixelValue(double val) { this->_maxPixelValue = val; }
protected:
Ptr<QualityMSE> _qualityMSE;
double _maxPixelValue = QualityPSNR::MAX_PIXEL_VALUE_DEFAULT;
/** @brief Constructor */
QualityPSNR( Ptr<QualityMSE> qualityMSE, double maxPixelValue )
: _qualityMSE(std::move(qualityMSE))
, _maxPixelValue(maxPixelValue)
{}
// convert mse to psnr
static double _mse_to_psnr(double mse, double max_pixel_value)
{
return (mse == 0.)
? std::numeric_limits<double>::infinity()
: 10. * std::log10((max_pixel_value * max_pixel_value) / mse)
;
}
// convert scalar of mses to psnrs
static cv::Scalar _mse_to_psnr(cv::Scalar mse, double max_pixel_value)
{
for (int i = 0; i < mse.rows; ++i)
mse(i) = _mse_to_psnr(mse(i), max_pixel_value);
return mse;
}
}; // QualityPSNR
} // quality
} // cv
#endif