public void PropertyMaxPixelValue()
{
using (var refImage = Image("lenna.png"))
using (var psnr = QualityPSNR.Create(refImage))
{
const double value = 123.456;
psnr.MaxPixelValue = value;
Assert.Equal(value, psnr.MaxPixelValue, 6);
}
}
public void StaticCompute()
{
using (var refImage = Image("lenna.png"))
using (var targetImage = new Mat())
{
Cv2.GaussianBlur(refImage, targetImage, new Size(5, 5), 15);
var value = QualityPSNR.Compute(refImage, targetImage, null);
Assert.Equal(28.813382, value[0], 6);
Assert.Equal(28.171064, value[1], 6);
Assert.Equal(30.828286, value[2], 6);
}
}
public void Compute()
{
using (var refImage = Image("lenna.png"))
using (var targetImage = new Mat())
using (var psnr = QualityPSNR.Create(refImage))
{
Cv2.GaussianBlur(refImage, targetImage, new Size(5, 5), 15);
var value = psnr.Compute(targetImage);
Assert.Equal(28.893586, value[0], 6);
Assert.Equal(28.26987, value[1], 6);
Assert.Equal(31.088282, value[2], 6);
}
}
private void IdentifyDifferencesSingleFrame(int inFileIndex)
{
if (inFileIndex + 1 < _inputFramesFileNames.Count)
{
var frameA = Cv2.ImRead(_inputFramesFileNames[inFileIndex]);
var frameB = Cv2.ImRead(_inputFramesFileNames[inFileIndex + 1]);
var frameAResized = ScaleFrame(frameA);
var frameBResized = ScaleFrame(frameB);
var grayFrameA = new Mat();
var grayFrameB = new Mat();
Cv2.CvtColor(frameAResized, grayFrameA, ColorConversionCodes.RGB2GRAY);
Cv2.CvtColor(frameBResized, grayFrameB, ColorConversionCodes.RGB2GRAY);
Parallel.For(0, _frameDivisionDimensionY, new ParallelOptions {
MaxDegreeOfParallelism = Environment.ProcessorCount
}, ih =>
{
for (int iw = 0; iw < _frameDivisionDimensionX; iw++)
{
var x = grayFrameA.Width / _frameDivisionDimensionX * iw;
var y = grayFrameA.Height / _frameDivisionDimensionY * ih;
var h = grayFrameA.Height / _frameDivisionDimensionY;
var w = grayFrameA.Width / _frameDivisionDimensionX;
var grayFrameBlockA = grayFrameA[y, y + h, x, x + w];
var grayFrameBlockB = grayFrameB[y, y + h, x, x + w];
var qualityMetrics = QualityPSNR.Compute(grayFrameBlockA, grayFrameBlockB, null);
if (qualityMetrics.Val0 <= _similarityThreshold)
{
_frameCollector.CollectTempBlock(inFileIndex, iw, ih);
}
}
});
}
}
public static double PSNR(Bitmap reference, Bitmap compare)
{
Scalar scalar = QualityPSNR.Compute(InputArray.Create(BitmapConverter.ToMat(reference)), InputArray.Create(BitmapConverter.ToMat(compare)), null);
return((scalar[0] + scalar[1] + scalar[2]) / 3);
}