private void mvZero(Context context, PictureHeader ph, MPEGPred pred, int mbX, int mbY, int[][] mbPix)
{
if (ph.picture_coding_type == PictureHeader.PredictiveCoded)
{
pred.predict16x16NoMV(refFrames[0], mbX << 4, mbY << 4, ph.pictureCodingExtension == null ? PictureCodingExtension.Frame
: ph.pictureCodingExtension.picture_structure, 0, mbPix);
}
else
{
int[][] pp = mbPix;
if (context.lastPredB.macroblock_motion_backward == 1)
{
pred.predict16x16NoMV(refFrames[0], mbX << 4, mbY << 4, ph.pictureCodingExtension == null ? PictureCodingExtension.Frame
: ph.pictureCodingExtension.picture_structure, 1, pp);
pp = new int[][] { new int[mbPix[0].Length], new int[mbPix[1].Length], new int[mbPix[2].Length] };
}
if (context.lastPredB.macroblock_motion_forward == 1)
{
pred.predict16x16NoMV(refFrames[1], mbX << 4, mbY << 4, ph.pictureCodingExtension == null ? PictureCodingExtension.Frame
: ph.pictureCodingExtension.picture_structure, 0, pp);
if (mbPix != pp)
{
avgPred(mbPix, pp);
}
}
}
}
public static PictureHeader read(MemoryStream bb)
{
BitReader inb = new BitReader(bb);
PictureHeader ph = new PictureHeader();
ph.temporal_reference = inb.readNBit(10);
ph.picture_coding_type = inb.readNBit(3);
ph.vbv_delay = inb.readNBit(16);
if (ph.picture_coding_type == 2 || ph.picture_coding_type == 3)
{
ph.full_pel_forward_vector = inb.read1Bit();
ph.forward_f_code = inb.readNBit(3);
}
if (ph.picture_coding_type == 3)
{
ph.full_pel_backward_vector = inb.read1Bit();
ph.backward_f_code = inb.readNBit(3);
}
while (inb.read1Bit() == 1)
{
inb.readNBit(8);
}
return(ph);
}
public Picture decodeFrame(MemoryStream ByteBuffer, int[][] buf)
{
PictureHeader ph = readHeader(ByteBuffer);
if (refFrames[0] == null && ph.picture_coding_type > 1 || refFrames[1] == null && ph.picture_coding_type > 2)
{
throw new Exception("Not enough references to decode " + (ph.picture_coding_type == 1 ? "P" : "B")
+ " frame");
}
Context context = initContext(sh, ph);
Picture pic = new Picture(context.codedWidth, context.codedHeight, buf, context.color, new Rect(0, 0,
context.picWidth, context.picHeight));
if (ph.pictureCodingExtension != null && ph.pictureCodingExtension.picture_structure != PictureCodingExtension.Frame)
{
decodePicture(context, ph, ByteBuffer, buf, ph.pictureCodingExtension.picture_structure - 1, 1);
ph = readHeader(ByteBuffer);
context = initContext(sh, ph);
decodePicture(context, ph, ByteBuffer, buf, ph.pictureCodingExtension.picture_structure - 1, 1);
}
else
{
decodePicture(context, ph, ByteBuffer, buf, 0, 0);
}
if (ph.picture_coding_type == PictureHeader.IntraCoded ||
ph.picture_coding_type == PictureHeader.PredictiveCoded)
{
Picture unused = refFrames[1];
refFrames[1] = refFrames[0];
refFrames[0] = copyAndCreateIfNeeded(pic, unused);
}
return(pic);
}
private void resetDCPredictors(Context context, PictureHeader ph)
{
int rval = 1 << 7;
if (ph.pictureCodingExtension != null)
{
rval = 1 << (7 + ph.pictureCodingExtension.intra_dc_precision);
}
context.intra_dc_predictor[0] = context.intra_dc_predictor[1] = context.intra_dc_predictor[2] = rval;
}
public Picture decodePicture(Context context, PictureHeader ph, MemoryStream buffer, int[][] buf, int vertOff,
int vertStep)
{
int planeSize = context.codedWidth * context.codedHeight;
if (buf.Length < 3 || buf[0].Length < planeSize || buf[1].Length < planeSize || buf[2].Length < planeSize)
{
throw new Exception("ByteBuffer too small to hold output picture [" + context.codedWidth + "x"
+ context.codedHeight + "]");
}
try
{
MemoryStream segment;
while ((segment = MPEGUtil.nextSegment(buffer)) != null)
{
if (segment.get(3) >= MPEGConst.SLICE_START_CODE_FIRST && segment.get(3) <= MPEGConst.SLICE_START_CODE_LAST)
{
segment.position(4);
try
{
decodeSlice(ph, segment.get(3) & 0xff, context, buf, new BitReader(segment), vertOff, vertStep);
}
catch (Exception e)
{
//e.printStackTrace();
}
}
else if (segment.get(3) >= 0xB3 && segment.get(3) != 0xB6 && segment.get(3) != 0xB7)
{
throw new Exception("Unexpected start code " + segment.get(3));
}
else if (segment.get(3) == 0x0)
{
//buffer.reset();
break;
}
}
Picture pic = new Picture(context.codedWidth, context.codedHeight, buf, context.color);
if ((ph.picture_coding_type == PictureHeader.IntraCoded || ph.picture_coding_type == PictureHeader.PredictiveCoded) &&
ph.pictureCodingExtension != null && ph.pictureCodingExtension.picture_structure != PictureCodingExtension.Frame)
{
refFields[ph.pictureCodingExtension.picture_structure - 1] = copyAndCreateIfNeeded(pic,
refFields[ph.pictureCodingExtension.picture_structure - 1]);
}
return(pic);
}
catch (IOException e)
{
throw e;
}
}
private PictureHeader readHeader(MemoryStream buffer)
{
PictureHeader ph = null;
MemoryStream segment;
MemoryStream fork = buffer.duplicate();
while ((segment = MPEGUtil.nextSegment(fork)) != null)
{
int code = segment.getInt() & 0xff;
if (code == MPEGConst.SEQUENCE_HEADER_CODE)
{
SequenceHeader newSh = SequenceHeader.read(segment);
if (sh != null)
{
newSh.copyExtensions(sh);
}
sh = newSh;
}
else if (code == MPEGConst.GROUP_START_CODE)
{
gh = GOPHeader.read(segment);
}
else if (code == MPEGConst.PICTURE_START_CODE)
{
ph = PictureHeader.read(segment);
}
else if (code == MPEGConst.EXTENSION_START_CODE)
{
int extType = segment.get(4) >> 4;
if (extType == SequenceHeader.Sequence_Extension || extType == SequenceHeader.Sequence_Scalable_Extension ||
extType == SequenceHeader.Sequence_Display_Extension)
{
SequenceHeader.readExtension(segment, sh);
}
else
{
PictureHeader.readExtension(segment, ph, sh);
}
}
else if (code == MPEGConst.USER_DATA_START_CODE)
{
// do nothing
}
else
{
break;
}
buffer.position(fork.position());
}
return(ph);
}
protected Context initContext(SequenceHeader sh, PictureHeader ph)
{
Context context = new Context();
context.codedWidth = (sh.horizontal_size + 15) & ~0xf;
context.codedHeight = getCodedHeight(sh, ph);
context.mbWidth = (sh.horizontal_size + 15) >> 4;
context.mbHeight = (sh.vertical_size + 15) >> 4;
context.picWidth = sh.horizontal_size;
context.picHeight = sh.vertical_size;
int chromaFormat = SequenceExtension.Chroma420;
if (sh.sequenceExtension != null)
{
chromaFormat = sh.sequenceExtension.chroma_format;
}
context.color = getColor(chromaFormat);
context.scan = MPEGConst.scan[ph.pictureCodingExtension == null ? 0 : ph.pictureCodingExtension.alternate_scan];
int[] inter = sh.non_intra_quantiser_matrix == null?zigzag(MPEGConst.defaultQMatInter, context.scan)
: sh.non_intra_quantiser_matrix;
int[] intra = sh.intra_quantiser_matrix == null?zigzag(MPEGConst.defaultQMatIntra, context.scan)
: sh.intra_quantiser_matrix;
context.qMats = new int[][] { inter, inter, intra, intra };
if (ph.quantMatrixExtension != null)
{
if (ph.quantMatrixExtension.non_intra_quantiser_matrix != null)
{
context.qMats[0] = ph.quantMatrixExtension.non_intra_quantiser_matrix;
}
if (ph.quantMatrixExtension.chroma_non_intra_quantiser_matrix != null)
{
context.qMats[1] = ph.quantMatrixExtension.chroma_non_intra_quantiser_matrix;
}
if (ph.quantMatrixExtension.intra_quantiser_matrix != null)
{
context.qMats[2] = ph.quantMatrixExtension.intra_quantiser_matrix;
}
if (ph.quantMatrixExtension.chroma_intra_quantiser_matrix != null)
{
context.qMats[3] = ph.quantMatrixExtension.chroma_intra_quantiser_matrix;
}
}
return(context);
}
public void decodeSlice(PictureHeader ph, int verticalPos, Context context, int[][] buf, BitReader ing, int vertOff,
int vertStep)
{
int stride = context.codedWidth;
resetDCPredictors(context, ph);
int mbRow = verticalPos - 1;
if (sh.vertical_size > 2800)
{
mbRow += (ing.readNBit(3) << 7);
}
if (sh.sequenceScalableExtension != null &&
sh.sequenceScalableExtension.scalable_mode == SequenceScalableExtension.DATA_PARTITIONING)
{
int priorityBreakpoint = ing.readNBit(7);
}
int qScaleCode = ing.readNBit(5);
if (ing.read1Bit() == 1)
{
int intraSlice = ing.read1Bit();
ing.skip(7);
while (ing.read1Bit() == 1)
{
ing.readNBit(8);
}
}
MPEGPred pred = new MPEGPred(ph.pictureCodingExtension != null ? ph.pictureCodingExtension.f_code
: new int[][] { new int[] { ph.forward_f_code, ph.forward_f_code },
new int[] { ph.backward_f_code, ph.backward_f_code } },
sh.sequenceExtension != null ? sh.sequenceExtension.chroma_format : SequenceExtension.Chroma420,
ph.pictureCodingExtension != null && ph.pictureCodingExtension.top_field_first == 0 ? false : true);
int[] ctx = new int[] { qScaleCode };
for (int prevAddr = mbRow * context.mbWidth - 1; ing.checkNBit(23) != 0;)
{
// TODO: decode skipped!!!
prevAddr = decodeMacroblock(ph, context, prevAddr, ctx, buf, stride, ing, vertOff, vertStep, pred);
context.mbNo++;
}
}
public static void readExtension(MemoryStream bb, PictureHeader ph, SequenceHeader sh)
{
ph.m_hasExtensions = true;
BitReader inb = new BitReader(bb);
int extType = inb.readNBit(4);
switch (extType)
{
case Quant_Matrix_Extension:
ph.quantMatrixExtension = QuantMatrixExtension.read(inb);
break;
case Copyright_Extension:
ph.copyrightExtension = CopyrightExtension.read(inb);
break;
case Picture_Display_Extension:
ph.pictureDisplayExtension = PictureDisplayExtension.read(inb, sh.sequenceExtension,
ph.pictureCodingExtension);
break;
case Picture_Coding_Extension:
ph.pictureCodingExtension = PictureCodingExtension.read(inb);
break;
case Picture_Spatial_Scalable_Extension:
ph.pictureSpatialScalableExtension = PictureSpatialScalableExtension.read(inb);
break;
case Picture_Temporal_Scalable_Extension:
ph.pictureTemporalScalableExtension = PictureTemporalScalableExtension.read(inb);
break;
default:
throw new Exception("Unsupported extension: " + extType);
}
}
public int decodeMacroblock(PictureHeader ph, Context context, int prevAddr, int[] qScaleCode, int[][] buf,
int stride, BitReader bits, int vertOff, int vertStep, MPEGPred pred)
{
int mbAddr = prevAddr;
while (bits.checkNBit(11) == 0x8)
{
bits.skip(11);
mbAddr += 33;
}
mbAddr += MPEGConst.vlcAddressIncrement.readVLC(bits) + 1;
int chromaFormat = SequenceExtension.Chroma420;
if (sh.sequenceExtension != null)
{
chromaFormat = sh.sequenceExtension.chroma_format;
}
for (int i = prevAddr + 1; i < mbAddr; i++)
{
int[][] predFwda = new int[][] { new int[256], new int[1 << (chromaFormat + 5)],
new int[1 << (chromaFormat + 5)] };
int mbXa = i % context.mbWidth;
int mbYa = i / context.mbWidth;
if (ph.picture_coding_type == PictureHeader.PredictiveCoded)
{
pred.reset();
}
mvZero(context, ph, pred, mbXa, mbYa, predFwda);
put(predFwda, buf, stride, chromaFormat, mbXa, mbYa, context.codedWidth, context.codedHeight >> vertStep,
vertOff, vertStep);
}
VLC vlcMBTypea = MPEGConst.vlcMBType(ph.picture_coding_type, sh.sequenceScalableExtension);
nVideo.Codecs.MPEG12.MPEGConst.MBType[] mbTypeVal = MPEGConst.mbTypeVal(ph.picture_coding_type, sh.sequenceScalableExtension);
nVideo.Codecs.MPEG12.MPEGConst.MBType mbType = mbTypeVal[vlcMBTypea.readVLC(bits)];
if (mbType.macroblock_intra != 1 || (mbAddr - prevAddr) > 1)
{
resetDCPredictors(context, ph);
}
int spatial_temporal_weight_code = 0;
if (mbType.spatial_temporal_weight_code_flag == 1 && ph.pictureSpatialScalableExtension != null &&
ph.pictureSpatialScalableExtension.spatial_temporal_weight_code_table_index != 0)
{
spatial_temporal_weight_code = bits.readNBit(2);
}
int motion_type = -1;
if (mbType.macroblock_motion_forward != 0 || mbType.macroblock_motion_backward != 0)
{
if (ph.pictureCodingExtension == null || ph.pictureCodingExtension.picture_structure == PictureCodingExtension.Frame &&
ph.pictureCodingExtension.frame_pred_frame_dct == 1)
{
motion_type = 2;
}
else
{
motion_type = bits.readNBit(2);
}
}
int dctType = 0;
if (ph.pictureCodingExtension != null && ph.pictureCodingExtension.picture_structure == PictureCodingExtension.Frame &&
ph.pictureCodingExtension.frame_pred_frame_dct == 0 &&
(mbType.macroblock_intra != 0 || mbType.macroblock_pattern != 0))
{
dctType = bits.read1Bit();
}
// buf[3][mbAddr] = dctType;
if (mbType.macroblock_quant != 0)
{
qScaleCode[0] = bits.readNBit(5);
}
bool concealmentMv = ph.pictureCodingExtension != null &&
ph.pictureCodingExtension.concealment_motion_vectors != 0;
int[][] predFwd = null;
int mbX = mbAddr % context.mbWidth;
int mbY = mbAddr / context.mbWidth;
if (mbType.macroblock_intra == 1)
{
if (concealmentMv)
{
// TODO read consealment vectors
}
else
{
pred.reset();
}
}
else if (mbType.macroblock_motion_forward != 0)
{
int refIdx = ph.picture_coding_type == PictureHeader.PredictiveCoded ? 0 : 1;
predFwd = new int[][] { new int[256], new int[1 << (chromaFormat + 5)], new int[1 << (chromaFormat + 5)] };
if (ph.pictureCodingExtension == null || ph.pictureCodingExtension.picture_structure == PictureCodingExtension.Frame)
{
pred.predictInFrame(refFrames[refIdx], mbX << 4, mbY << 4, predFwd, bits, motion_type, 0,
spatial_temporal_weight_code);
}
else
{
if (ph.picture_coding_type == PictureHeader.PredictiveCoded)
{
pred.predictInField(refFields, mbX << 4, mbY << 4, predFwd, bits, motion_type, 0,
ph.pictureCodingExtension.picture_structure - 1);
}
else
{
pred.predictInField(new Picture[] { refFrames[refIdx], refFrames[refIdx] }, mbX << 4, mbY << 4,
predFwd, bits, motion_type, 0, ph.pictureCodingExtension.picture_structure - 1);
}
}
}
else if (ph.picture_coding_type == PictureHeader.PredictiveCoded)
{
predFwd = new int[][] { new int[256], new int[1 << (chromaFormat + 5)], new int[1 << (chromaFormat + 5)] };
pred.reset();
mvZero(context, ph, pred, mbX, mbY, predFwd);
}
int[][] predBack = null;
if (mbType.macroblock_motion_backward != 0)
{
predBack = new int[][] { new int[256], new int[1 << (chromaFormat + 5)], new int[1 << (chromaFormat + 5)] };
if (ph.pictureCodingExtension == null || ph.pictureCodingExtension.picture_structure == PictureCodingExtension.Frame)
{
pred.predictInFrame(refFrames[0], mbX << 4, mbY << 4, predBack, bits, motion_type, 1,
spatial_temporal_weight_code);
}
else
{
pred.predictInField(new Picture[] { refFrames[0], refFrames[0] }, mbX << 4, mbY << 4, predBack, bits,
motion_type, 1, ph.pictureCodingExtension.picture_structure - 1);
}
}
context.lastPredB = mbType;
int[][] pp = mbType.macroblock_intra == 1 ? new int[][] { new int[256], new int[1 << (chromaFormat + 5)],
new int[1 << (chromaFormat + 5)] } : buildPred(predFwd, predBack);
//if (mbType.macroblock_intra != 0 && concealmentMv)
//Assert.assertEquals(1, bits.read1Bit()); // Marker
int cbp = mbType.macroblock_intra == 1 ? 0xfff : 0;
if (mbType.macroblock_pattern != 0)
{
cbp = readCbPattern(bits);
}
VLC vlcCoeff = MPEGConst.vlcCoeff0;
if (ph.pictureCodingExtension != null && mbType.macroblock_intra == 1 &&
ph.pictureCodingExtension.intra_vlc_format == 1)
{
vlcCoeff = MPEGConst.vlcCoeff1;
}
int[] qScaleTab = ph.pictureCodingExtension != null && ph.pictureCodingExtension.q_scale_type == 1 ? MPEGConst.qScaleTab2
: MPEGConst.qScaleTab1;
int qScale = qScaleTab[qScaleCode[0]];
int intra_dc_mult = 8;
if (ph.pictureCodingExtension != null)
{
intra_dc_mult = 8 >> ph.pictureCodingExtension.intra_dc_precision;
}
int blkCount = 6 + (chromaFormat == SequenceExtension.Chroma420 ? 0 : (chromaFormat == SequenceExtension.Chroma422 ? 2 : 6));
int[] block = new int[64];
// System.out.print(mbAddr + ": ");
for (int i = 0, cbpMask = 1 << (blkCount - 1); i < blkCount; i++, cbpMask >>= 1)
{
if ((cbp & cbpMask) == 0)
{
continue;
}
int[] qmat = context.qMats[(i >= 4 ? 1 : 0) + (mbType.macroblock_intra << 1)];
if (mbType.macroblock_intra == 1)
{
blockIntra(bits, vlcCoeff, block, context.intra_dc_predictor, i, context.scan,
sh.hasExtensions() || ph.hasExtensions() ? 12 : 8, intra_dc_mult, qScale, qmat);
}
else
{
blockInter(bits, vlcCoeff, block, context.scan,
sh.hasExtensions() || ph.hasExtensions() ? 12 : 8, qScale, qmat);
}
mapBlock(block, pp[MPEGConst.BLOCK_TO_CC[i]], i, dctType, chromaFormat);
}
put(pp, buf, stride, chromaFormat, mbX, mbY, context.codedWidth, context.codedHeight >> vertStep, vertOff,
vertStep);
return(mbAddr);
}
public static int getCodedHeight(SequenceHeader sh, PictureHeader ph)
{
int field = ph.pictureCodingExtension != null && ph.pictureCodingExtension.picture_structure != PictureCodingExtension.Frame ? 1 : 0;
return((((sh.vertical_size >> field) + 15) & ~0xf) << field);
}
