private TiffYCbCrConverter16(TiffRational[] luma, TiffRational[] referenceBlackWhite)
{
_expanderY = new CodingRangeExpander(referenceBlackWhite[0], referenceBlackWhite[1], ushort.MaxValue);
_expanderCb = new CodingRangeExpander(referenceBlackWhite[2], referenceBlackWhite[3], ushort.MaxValue / 2);
_expanderCr = new CodingRangeExpander(referenceBlackWhite[4], referenceBlackWhite[5], ushort.MaxValue / 2);
_converterFrom = new YCbCrToRgbConverter(luma[0], luma[1], luma[2]);
}
public void ConvertToRgba32(ReadOnlySpan <byte> ycbcr, Span <TiffRgba32> destination, int count)
{
CodingRangeExpander expanderY = _expanderY;
CodingRangeExpander expanderCb = _expanderCb;
CodingRangeExpander expanderCr = _expanderCr;
YCbCrToRgbConverter converter = _converterFrom;
ref byte sourceRef = ref MemoryMarshal.GetReference(ycbcr);
private TiffYCbCrConverter8(TiffRational[] luma, TiffRational[] referenceBlackWhite)
{
_expanderY = new CodingRangeExpander(referenceBlackWhite[0], referenceBlackWhite[1], 255);
_expanderCb = new CodingRangeExpander(referenceBlackWhite[2], referenceBlackWhite[3], 127);
_expanderCr = new CodingRangeExpander(referenceBlackWhite[4], referenceBlackWhite[5], 127);
_converterFrom = new YCbCrToRgbConverter(luma[0], luma[1], luma[2]);
_shrinkerY = new CodingRangeShrinker(referenceBlackWhite[0], referenceBlackWhite[1], 255);
_shrinkerCb = new CodingRangeShrinker(referenceBlackWhite[2], referenceBlackWhite[3], 127);
_shrinkerCr = new CodingRangeShrinker(referenceBlackWhite[4], referenceBlackWhite[5], 127);
_converterTo = new RgbToYCbCrConverter(luma[0], luma[1], luma[2]);
}
public TiffRgba32 ConvertToRgba32(byte y, byte cb, byte cr)
{
CodingRangeExpander expanderY = _expanderY;
CodingRangeExpander expanderCb = _expanderCb;
CodingRangeExpander expanderCr = _expanderCr;
YCbCrToRgbConverter converter = _converterFrom;
float y64 = expanderY.Expand(y);
float cb64 = expanderCb.Expand(cb);
float cr64 = expanderCr.Expand(cr);
TiffRgba32 pixel = default; // TODO: SkipInit
converter.Convert(y64, cb64, cr64, ref pixel);
return(pixel);
}
public YCbCrConverter(Rational[] referenceBlackAndWhite, Rational[] coefficients)
{
referenceBlackAndWhite ??= DefaultReferenceBlackWhite;
coefficients ??= DefaultLuma;
if (referenceBlackAndWhite.Length != 6)
{
TiffThrowHelper.ThrowImageFormatException("reference black and white array should have 6 entry's");
}
if (coefficients.Length != 3)
{
TiffThrowHelper.ThrowImageFormatException("luma coefficients array should have 6 entry's");
}
this.yExpander = new CodingRangeExpander(referenceBlackAndWhite[0], referenceBlackAndWhite[1], 255);
this.cbExpander = new CodingRangeExpander(referenceBlackAndWhite[2], referenceBlackAndWhite[3], 127);
this.crExpander = new CodingRangeExpander(referenceBlackAndWhite[4], referenceBlackAndWhite[5], 127);
this.converter = new YCbCrToRgbConverter(coefficients[0], coefficients[1], coefficients[2]);
}
