public void YCbCrToRGBTest()
{
const int maxVariance = 1;
byte[][][] raster = GetRaster();
for (short y = 0; y < height; y++)
{
for (short x = 0; x < width; x++)
{
// Convert values via slower method.
byte r1 = raster[yIndex][x][y];
byte g1 = raster[cbIndex][x][y];
byte b1 = raster[crIndex][x][y];
YCbCr.toRGBSlow(ref r1, ref g1, ref b1);
// Convert values via experimental faster method.
byte r2 = raster[yIndex][x][y];
byte g2 = raster[cbIndex][x][y];
byte b2 = raster[crIndex][x][y];
YCbCr.toRGB(ref r2, ref g2, ref b2);
Assert.IsTrue(Math.Abs(r1 - r2) <= maxVariance);
Assert.IsTrue(Math.Abs(r1 - r2) <= maxVariance);
Assert.IsTrue(Math.Abs(r1 - r2) <= maxVariance);
}
}
}
public void YCbCrToRGBPerformanceTest()
{
byte[][][] raster = GetRaster();
const int runs = 20;
const int iterations = 100;
var slowPerf = new PerformanceMonitor("TheoreticallySlower", runs);
var fastPerf = new PerformanceMonitor("TheoreticallyFaster", runs);
for (int run = 0; run < runs; run++)
{
slowPerf.Start();
for (int i = 0; i < iterations; i++)
{
for (short y = 0; y < height; y++)
{
for (short x = 0; x < width; x++)
{
byte r1 = raster[yIndex][x][y];
byte g1 = raster[cbIndex][x][y];
byte b1 = raster[crIndex][x][y];
YCbCr.toRGBSlow(ref r1, ref g1, ref b1);
}
}
}
slowPerf.Stop();
fastPerf.Start();
for (int i = 0; i < iterations; i++)
{
for (short y = 0; y < height; y++)
{
for (short x = 0; x < width; x++)
{
byte r1 = raster[yIndex][x][y];
byte g1 = raster[cbIndex][x][y];
byte b1 = raster[crIndex][x][y];
YCbCr.toRGB(ref r1, ref g1, ref b1);
}
}
}
fastPerf.Stop();
}
Assert.IsTrue(fastPerf.AverageCompletionTimeInMs < slowPerf.AverageCompletionTimeInMs,
"The fast conversion method took {0:0.00} ms, while the slow method took {0:0.00} ms", fastPerf.AverageCompletionTimeInMs, slowPerf.AverageCompletionTimeInMs);
}
private void GetUpsampledRgba(byte[][][] raster, byte[] frame)
{
// Convert the three-layer raster image to RGBA format.
int pos = 0;
for (int y = 0; y < height; y++)
{
for (int x = 0; x < width; x++)
{
int posBlue = pos++;
int posGreen = pos++;
int posRed = pos++;
frame[posRed] = raster[yIndex][x][y];
frame[posGreen] = raster[cbIndex][x][y];
frame[posBlue] = raster[crIndex][x][y];
YCbCr.toRGB(ref frame[posRed], ref frame[posGreen], ref frame[posBlue]);
frame[pos++] = alphaValue;
}
}
}
