/// <summary>
/// Same as CodeResiduals, but doesn't actually write anything.
/// Instead, it just records the event distribution.
/// </summary>
private void RecordResiduals(Vp8EncIterator it, Vp8ModeScore rd)
{
int x, y, ch;
var residual = new Vp8Residual();
bool i16 = it.CurrentMacroBlockInfo.MacroBlockType == Vp8MacroBlockType.I16X16;
it.NzToBytes();
if (i16)
{
// i16x16
residual.Init(0, 1, this.Proba);
residual.SetCoeffs(rd.YDcLevels);
int res = residual.RecordCoeffs(it.TopNz[8] + it.LeftNz[8]);
it.TopNz[8] = res;
it.LeftNz[8] = res;
residual.Init(1, 0, this.Proba);
}
else
{
residual.Init(0, 3, this.Proba);
}
// luma-AC
for (y = 0; y < 4; y++)
{
for (x = 0; x < 4; x++)
{
int ctx = it.TopNz[x] + it.LeftNz[y];
Span <short> coeffs = rd.YAcLevels.AsSpan(16 * (x + (y * 4)), 16);
residual.SetCoeffs(coeffs);
int res = residual.RecordCoeffs(ctx);
it.TopNz[x] = res;
it.LeftNz[y] = res;
}
}
// U/V
residual.Init(0, 2, this.Proba);
for (ch = 0; ch <= 2; ch += 2)
{
for (y = 0; y < 2; y++)
{
for (x = 0; x < 2; x++)
{
int ctx = it.TopNz[4 + ch + x] + it.LeftNz[4 + ch + y];
residual.SetCoeffs(rd.UvLevels.AsSpan(16 * ((ch * 2) + x + (y * 2)), 16));
int res = residual.RecordCoeffs(ctx);
it.TopNz[4 + ch + x] = res;
it.LeftNz[4 + ch + y] = res;
}
}
}
it.BytesToNz();
}
private void CodeResiduals(Vp8EncIterator it, Vp8ModeScore rd, Vp8Residual residual)
{
int x, y, ch;
bool i16 = it.CurrentMacroBlockInfo.MacroBlockType == Vp8MacroBlockType.I16X16;
int segment = it.CurrentMacroBlockInfo.Segment;
it.NzToBytes();
int pos1 = this.bitWriter.NumBytes();
if (i16)
{
residual.Init(0, 1, this.Proba);
residual.SetCoeffs(rd.YDcLevels);
int res = this.bitWriter.PutCoeffs(it.TopNz[8] + it.LeftNz[8], residual);
it.TopNz[8] = it.LeftNz[8] = res;
residual.Init(1, 0, this.Proba);
}
else
{
residual.Init(0, 3, this.Proba);
}
// luma-AC
for (y = 0; y < 4; y++)
{
for (x = 0; x < 4; x++)
{
int ctx = it.TopNz[x] + it.LeftNz[y];
Span <short> coeffs = rd.YAcLevels.AsSpan(16 * (x + (y * 4)), 16);
residual.SetCoeffs(coeffs);
int res = this.bitWriter.PutCoeffs(ctx, residual);
it.TopNz[x] = it.LeftNz[y] = res;
}
}
int pos2 = this.bitWriter.NumBytes();
// U/V
residual.Init(0, 2, this.Proba);
for (ch = 0; ch <= 2; ch += 2)
{
for (y = 0; y < 2; y++)
{
for (x = 0; x < 2; x++)
{
int ctx = it.TopNz[4 + ch + x] + it.LeftNz[4 + ch + y];
residual.SetCoeffs(rd.UvLevels.AsSpan(16 * ((ch * 2) + x + (y * 2)), 16));
int res = this.bitWriter.PutCoeffs(ctx, residual);
it.TopNz[4 + ch + x] = it.LeftNz[4 + ch + y] = res;
}
}
}
int pos3 = this.bitWriter.NumBytes();
it.LumaBits = pos2 - pos1;
it.UvBits = pos3 - pos2;
it.BitCount[segment, i16 ? 1 : 0] += it.LumaBits;
it.BitCount[segment, 2] += it.UvBits;
it.BytesToNz();
}