/// <summary>
/// Accumulate a token 'v' into a histogram.
/// </summary>
/// <param name="v">The token to add.</param>
/// <param name="useDistanceModifier">Indicates whether to use the distance modifier.</param>
/// <param name="xSize">xSize is only used when useDistanceModifier is true.</param>
public void AddSinglePixOrCopy(PixOrCopy v, bool useDistanceModifier, int xSize = 0)
{
if (v.IsLiteral())
{
this.Alpha[v.Literal(3)]++;
this.Red[v.Literal(2)]++;
this.Literal[v.Literal(1)]++;
this.Blue[v.Literal(0)]++;
}
else if (v.IsCacheIdx())
{
int literalIx = (int)(WebpConstants.NumLiteralCodes + WebpConstants.NumLengthCodes + v.CacheIdx());
this.Literal[literalIx]++;
}
else
{
int extraBits = 0;
int code = LosslessUtils.PrefixEncodeBits(v.Length(), ref extraBits);
this.Literal[WebpConstants.NumLiteralCodes + code]++;
if (!useDistanceModifier)
{
code = LosslessUtils.PrefixEncodeBits((int)v.Distance(), ref extraBits);
}
else
{
code = LosslessUtils.PrefixEncodeBits(BackwardReferenceEncoder.DistanceToPlaneCode(xSize, (int)v.Distance()), ref extraBits);
}
this.Distance[code]++;
}
}
