private bool Decimate(Vp8EncIterator it, ref Vp8ModeScore rd, Vp8RdLevel rdOpt)
{
rd.InitScore();
// We can perform predictions for Luma16x16 and Chroma8x8 already.
// Luma4x4 predictions needs to be done as-we-go.
it.MakeLuma16Preds();
it.MakeChroma8Preds();
if (rdOpt > Vp8RdLevel.RdOptNone)
{
QuantEnc.PickBestIntra16(it, ref rd, this.SegmentInfos, this.Proba);
if (this.method >= WebpEncodingMethod.Level2)
{
QuantEnc.PickBestIntra4(it, ref rd, this.SegmentInfos, this.Proba, this.maxI4HeaderBits);
}
QuantEnc.PickBestUv(it, ref rd, this.SegmentInfos, this.Proba);
}
else
{
// At this point we have heuristically decided intra16 / intra4.
// For method >= 2, pick the best intra4/intra16 based on SSE (~tad slower).
// For method <= 1, we don't re-examine the decision but just go ahead with
// quantization/reconstruction.
QuantEnc.RefineUsingDistortion(it, this.SegmentInfos, rd, this.method >= WebpEncodingMethod.Level2, this.method >= WebpEncodingMethod.Level1, this.MbHeaderLimit);
}
bool isSkipped = rd.Nz == 0;
it.SetSkip(isSkipped);
return(isSkipped);
}