private static PredictionMode ReadInterMode(ref Vp9Common cm, ref MacroBlockD xd, ref Reader r, int ctx)
{
int mode = r.ReadTree(Luts.Vp9InterModeTree, cm.Fc.Value.InterModeProb[ctx].ToSpan());
if (!xd.Counts.IsNull)
{
++xd.Counts.Value.InterMode[ctx][mode];
}
return(PredictionMode.NearestMv + mode);
}
private static PredictionMode ReadIntraModeY(ref Vp9Common cm, ref MacroBlockD xd, ref Reader r, int sizeGroup)
{
PredictionMode yMode = ReadIntraMode(ref r, cm.Fc.Value.YModeProb[sizeGroup].ToSpan());
if (!xd.Counts.IsNull)
{
++xd.Counts.Value.YMode[sizeGroup][(int)yMode];
}
return(yMode);
}
private static PredictionMode ReadIntraModeUv(ref Vp9Common cm, ref MacroBlockD xd, ref Reader r, byte yMode)
{
PredictionMode uvMode = ReadIntraMode(ref r, cm.Fc.Value.UvModeProb[yMode].ToSpan());
if (!xd.Counts.IsNull)
{
++xd.Counts.Value.UvMode[yMode][(int)uvMode];
}
return(uvMode);
}
private static void SetSegmentId(ref Vp9Common cm, int miOffset, int xMis, int yMis, int segmentId)
{
int x, y;
Debug.Assert(segmentId >= 0 && segmentId < Constants.MaxSegments);
for (y = 0; y < yMis; y++)
{
for (x = 0; x < xMis; x++)
{
cm.CurrentFrameSegMap[miOffset + y * cm.MiCols + x] = (byte)segmentId;
}
}
}
private static int DecGetSegmentId(ref Vp9Common cm, ArrayPtr <byte> segmentIds, int miOffset, int xMis, int yMis)
{
int x, y, segmentId = int.MaxValue;
for (y = 0; y < yMis; y++)
{
for (x = 0; x < xMis; x++)
{
segmentId = Math.Min(segmentId, segmentIds[miOffset + y * cm.MiCols + x]);
}
}
Debug.Assert(segmentId >= 0 && segmentId < Constants.MaxSegments);
return(segmentId);
}
private static TxSize ReadTxSize(ref Vp9Common cm, ref MacroBlockD xd, bool allowSelect, ref Reader r)
{
TxMode txMode = cm.TxMode;
BlockSize bsize = xd.Mi[0].Value.SbType;
TxSize maxTxSize = Luts.MaxTxSizeLookup[(int)bsize];
if (allowSelect && txMode == TxMode.TxModeSelect && bsize >= BlockSize.Block8x8)
{
return(ReadSelectedTxSize(ref cm, ref xd, maxTxSize, ref r));
}
else
{
return((TxSize)Math.Min((int)maxTxSize, (int)Luts.TxModeToBiggestTxSize[(int)txMode]));
}
}
public static int GetReferenceModeContext(ref Vp9Common cm, ref MacroBlockD xd)
{
int ctx;
// Note:
// The mode info data structure has a one element border above and to the
// left of the entries corresponding to real macroblocks.
// The prediction flags in these dummy entries are initialized to 0.
if (!xd.AboveMi.IsNull && !xd.LeftMi.IsNull)
{ // both edges available
if (!xd.AboveMi.Value.HasSecondRef() && !xd.LeftMi.Value.HasSecondRef())
{
// Neither edge uses comp pred (0/1)
ctx = (xd.AboveMi.Value.RefFrame[0] == cm.CompFixedRef ? 1 : 0) ^
(xd.LeftMi.Value.RefFrame[0] == cm.CompFixedRef ? 1 : 0);
}
else if (!xd.AboveMi.Value.HasSecondRef())
{
// One of two edges uses comp pred (2/3)
ctx = 2 + (xd.AboveMi.Value.RefFrame[0] == cm.CompFixedRef || !xd.AboveMi.Value.IsInterBlock() ? 1 : 0);
}
else if (!xd.LeftMi.Value.HasSecondRef())
{
// One of two edges uses comp pred (2/3)
ctx = 2 + (xd.LeftMi.Value.RefFrame[0] == cm.CompFixedRef || !xd.LeftMi.Value.IsInterBlock() ? 1 : 0);
}
else // Both edges use comp pred (4)
{
ctx = 4;
}
}
else if (!xd.AboveMi.IsNull || !xd.LeftMi.IsNull)
{ // One edge available
ref ModeInfo edgeMi = ref !xd.AboveMi.IsNull ? ref xd.AboveMi.Value : ref xd.LeftMi.Value;
if (!edgeMi.HasSecondRef())
{
// Edge does not use comp pred (0/1)
ctx = edgeMi.RefFrame[0] == cm.CompFixedRef ? 1 : 0;
}
else
{
// Edge uses comp pred (3)
ctx = 3;
}
}
private static void CopySegmentId(
ref Vp9Common cm,
ArrayPtr <byte> lastSegmentIds,
ArrayPtr <byte> currentSegmentIds,
int miOffset,
int xMis,
int yMis)
{
int x, y;
for (y = 0; y < yMis; y++)
{
for (x = 0; x < xMis; x++)
{
currentSegmentIds[miOffset + y * cm.MiCols + x] = (byte)(!lastSegmentIds.IsNull ? lastSegmentIds[miOffset + y * cm.MiCols + x] : 0);
}
}
}
private static void SetMvs(ref Vp9Common cm, ReadOnlySpan <Vp9MvRef> mvs)
{
if (mvs.Length > cm.PrevFrameMvs.Length)
{
throw new ArgumentException($"Size mismatch, expected: {cm.PrevFrameMvs.Length}, but got: {mvs.Length}.");
}
for (int i = 0; i < mvs.Length; i++)
{
ref var mv = ref cm.PrevFrameMvs[i];
mv.Mv[0].Row = mvs[i].Mvs[0].Row;
mv.Mv[0].Col = mvs[i].Mvs[0].Col;
mv.Mv[1].Row = mvs[i].Mvs[1].Row;
mv.Mv[1].Col = mvs[i].Mvs[1].Col;
mv.RefFrame[0] = (sbyte)mvs[i].RefFrames[0];
mv.RefFrame[1] = (sbyte)mvs[i].RefFrames[1];
}
private static TxSize ReadSelectedTxSize(ref Vp9Common cm, ref MacroBlockD xd, TxSize maxTxSize, ref Reader r)
{
int ctx = xd.GetTxSizeContext();
ReadOnlySpan <byte> txProbs = GetTxProbs(ref cm.Fc.Value, maxTxSize, ctx);
TxSize txSize = (TxSize)r.Read(txProbs[0]);
if (txSize != TxSize.Tx4x4 && maxTxSize >= TxSize.Tx16x16)
{
txSize += r.Read(txProbs[1]);
if (txSize != TxSize.Tx8x8 && maxTxSize >= TxSize.Tx32x32)
{
txSize += r.Read(txProbs[2]);
}
}
if (!xd.Counts.IsNull)
{
++GetTxCounts(ref xd.Counts.Value, maxTxSize, ctx)[(int)txSize];
}
return(txSize);
}
public unsafe bool Decode(
ref Vp9PictureInfo pictureInfo,
ISurface output,
ReadOnlySpan <byte> bitstream,
ReadOnlySpan <Vp9MvRef> mvsIn,
Span <Vp9MvRef> mvsOut)
{
Vp9Common cm = new Vp9Common();
cm.FrameType = pictureInfo.IsKeyFrame ? FrameType.KeyFrame : FrameType.InterFrame;
cm.IntraOnly = pictureInfo.IntraOnly;
cm.Width = output.Width;
cm.Height = output.Height;
cm.SubsamplingX = 1;
cm.SubsamplingY = 1;
cm.UsePrevFrameMvs = pictureInfo.UsePrevInFindMvRefs;
cm.RefFrameSignBias = pictureInfo.RefFrameSignBias;
cm.BaseQindex = pictureInfo.BaseQIndex;
cm.YDcDeltaQ = pictureInfo.YDcDeltaQ;
cm.UvAcDeltaQ = pictureInfo.UvAcDeltaQ;
cm.UvDcDeltaQ = pictureInfo.UvDcDeltaQ;
cm.Mb.Lossless = pictureInfo.Lossless;
cm.Mb.Bd = 8;
cm.TxMode = (TxMode)pictureInfo.TransformMode;
cm.AllowHighPrecisionMv = pictureInfo.AllowHighPrecisionMv;
cm.InterpFilter = (byte)pictureInfo.InterpFilter;
if (cm.InterpFilter != Constants.Switchable)
{
cm.InterpFilter = LiteralToFilter[cm.InterpFilter];
}
cm.ReferenceMode = (ReferenceMode)pictureInfo.ReferenceMode;
cm.CompFixedRef = pictureInfo.CompFixedRef;
cm.CompVarRef = pictureInfo.CompVarRef;
cm.Log2TileCols = pictureInfo.Log2TileCols;
cm.Log2TileRows = pictureInfo.Log2TileRows;
cm.Seg.Enabled = pictureInfo.SegmentEnabled;
cm.Seg.UpdateMap = pictureInfo.SegmentMapUpdate;
cm.Seg.TemporalUpdate = pictureInfo.SegmentMapTemporalUpdate;
cm.Seg.AbsDelta = (byte)pictureInfo.SegmentAbsDelta;
cm.Seg.FeatureMask = pictureInfo.SegmentFeatureEnable;
cm.Seg.FeatureData = pictureInfo.SegmentFeatureData;
cm.Lf.ModeRefDeltaEnabled = pictureInfo.ModeRefDeltaEnabled;
cm.Lf.RefDeltas = pictureInfo.RefDeltas;
cm.Lf.ModeDeltas = pictureInfo.ModeDeltas;
cm.Fc = new Ptr <Vp9EntropyProbs>(ref pictureInfo.Entropy);
cm.Counts = new Ptr <Vp9BackwardUpdates>(ref pictureInfo.BackwardUpdateCounts);
cm.FrameRefs[0].Buf = (Surface)pictureInfo.LastReference;
cm.FrameRefs[1].Buf = (Surface)pictureInfo.GoldenReference;
cm.FrameRefs[2].Buf = (Surface)pictureInfo.AltReference;
cm.Mb.CurBuf = (Surface)output;
cm.Mb.SetupBlockPlanes(1, 1);
int tileCols = 1 << pictureInfo.Log2TileCols;
int tileRows = 1 << pictureInfo.Log2TileRows;
// Video usually have only 4 columns, so more threads won't make a difference for those.
// Try to not take all CPU cores for video decoding.
int maxThreads = Math.Min(4, Environment.ProcessorCount / 2);
cm.AllocTileWorkerData(_allocator, tileCols, tileRows, maxThreads);
cm.AllocContextBuffers(_allocator, output.Width, output.Height);
cm.InitContextBuffers();
cm.SetupSegmentationDequant();
cm.SetupScaleFactors();
SetMvs(ref cm, mvsIn);
fixed(byte *dataPtr = bitstream)
{
try
{
if (maxThreads > 1 && tileRows == 1 && tileCols > 1)
{
DecodeFrame.DecodeTilesMt(ref cm, new ArrayPtr <byte>(dataPtr, bitstream.Length), maxThreads);
}
else
{
DecodeFrame.DecodeTiles(ref cm, new ArrayPtr <byte>(dataPtr, bitstream.Length));
}
}
catch (InternalErrorException)
{
return(false);
}
}
GetMvs(ref cm, mvsOut);
cm.FreeTileWorkerData(_allocator);
cm.FreeContextBuffers(_allocator);
return(true);
}
private static int ReadIntraSegmentId(ref Vp9Common cm, int miOffset, int xMis, int yMis, ref Reader r)
{
ref Segmentation seg = ref cm.Seg;