// (8.6.1)
void decode_quantization_parameters(decoder_context* ctx,
thread_context* tctx, int xC,int yC)
{
logtrace(LogTransform,"decode_quantization_parameters(int xC,int yC)=(%d,%d)\n", xC,yC);
pic_parameter_set* pps = ctx->current_pps;
seq_parameter_set* sps = ctx->current_sps;
slice_segment_header* shdr = tctx->shdr;
// top left pixel position of current quantization group
int xQG = xC - (xC & ((1<<pps->Log2MinCuQpDeltaSize)-1));
int yQG = yC - (yC & ((1<<pps->Log2MinCuQpDeltaSize)-1));
// we only have to set QP in the first call in a quantization-group
/* TODO: check why this does not work with HoneyBee stream
if (xQG == tctx->currentQG_x &&
yQG == tctx->currentQG_y)
{
return;
}
*/
// if first QG in CU, remember last QPY of last CU previous QG
if (xQG != tctx->currentQG_x ||
yQG != tctx->currentQG_y)
{
tctx->lastQPYinPreviousQG = tctx->currentQPY;
tctx->currentQG_x = xQG;
tctx->currentQG_y = yQG;
}
int qPY_PRED;
bool firstQGInSlice;
bool firstQGInTile = false; // TODO
bool firstInCTBRow = (xQG==0); // TODO
int first_ctb_in_slice_RS = tctx->shdr->slice_segment_address;
int SliceStartX = (first_ctb_in_slice_RS % sps->PicWidthInCtbsY) * sps->CtbSizeY;
int SliceStartY = (first_ctb_in_slice_RS / sps->PicWidthInCtbsY) * sps->CtbSizeY;
firstQGInSlice = (SliceStartX == xQG && SliceStartY == yQG);
if (firstQGInSlice || firstQGInTile ||
(firstInCTBRow && pps->entropy_coding_sync_enabled_flag)) {
qPY_PRED = tctx->shdr->SliceQPY;
}
else {
qPY_PRED = tctx->lastQPYinPreviousQG;
}
int qPYA,qPYB;
if (available_zscan(ctx->img,xQG,yQG, xQG-1,yQG)) {
int xTmp = (xQG-1) >> sps->Log2MinTrafoSize;
int yTmp = (yQG ) >> sps->Log2MinTrafoSize;
int minTbAddrA = pps->MinTbAddrZS[xTmp + yTmp*sps->PicWidthInTbsY];
int ctbAddrA = (minTbAddrA>>2)*(sps->Log2CtbSizeY-sps->Log2MinTrafoSize);
if (ctbAddrA == tctx->CtbAddrInTS) {
qPYA = get_QPY(ctx->img,sps,xQG-1,yQG);
}
else {
qPYA = qPY_PRED;
}
}
// (8.6.1)
void decode_quantization_parameters(decoder_context* ctx,
thread_context* tctx, int xC,int yC)
{
pic_parameter_set* pps = ctx->current_pps;
seq_parameter_set* sps = ctx->current_sps;
slice_segment_header* shdr = tctx->shdr;
// top left pixel position of current quantization group
int xQG = xC - (xC & ((1<<pps->Log2MinCuQpDeltaSize)-1));
int yQG = yC - (yC & ((1<<pps->Log2MinCuQpDeltaSize)-1));
// if first QG in CU, remember last QPY of last CU previous QG
if ((xQG & ((1<<sps->Log2CtbSizeY)-1)) == 0 &&
(yQG & ((1<<sps->Log2CtbSizeY)-1)) == 0) {
tctx->lastQPYinPreviousQG = tctx->currentQPY;
}
int qPY_PRED;
bool firstQGInSlice;
bool firstQGInTile = false; // TODO
bool firstInCTBRow = (xC==0); // TODO
int first_ctb_in_slice_RS = tctx->shdr->slice_segment_address;
int SliceStartX = (first_ctb_in_slice_RS % sps->PicWidthInCtbsY) * sps->CtbSizeY;
int SliceStartY = (first_ctb_in_slice_RS / sps->PicWidthInCtbsY) * sps->CtbSizeY;
firstQGInSlice = (SliceStartX == xQG && SliceStartY == yQG);
if (firstQGInSlice || firstQGInTile ||
(firstInCTBRow && pps->entropy_coding_sync_enabled_flag)) {
qPY_PRED = tctx->shdr->SliceQPY;
}
else {
qPY_PRED = tctx->lastQPYinPreviousQG;
}
int qPYA,qPYB;
if (available_zscan(ctx,xQG,yQG, xQG-1,yQG)) {
// unused: int xTmp = (xQG-1) >> sps->Log2MinTrafoSize;
// unused: int yTmp = (yQG ) >> sps->Log2MinTrafoSize;
// unused: int minTbAddrA = pps->MinTbAddrZS[xTmp + yTmp*sps->PicWidthInTbsY];
// unused: int ctbAddrA = (minTbAddrA>>2)*(sps->Log2CtbSizeY-sps->Log2MinTrafoSize);
qPYA = get_QPY(ctx,xQG-1,yQG);
}
else {
qPYA = qPY_PRED;
}
if (available_zscan(ctx,xQG,yQG, xQG,yQG-1)) {
// unused: int xTmp = (xQG ) >> sps->Log2MinTrafoSize;
// unused: int yTmp = (yQG-1) >> sps->Log2MinTrafoSize;
// unused: int minTbAddrA = pps->MinTbAddrZS[xTmp + yTmp*sps->PicWidthInTbsY];
// unused: int ctbAddrA = (minTbAddrA>>2)*(sps->Log2CtbSizeY-sps->Log2MinTrafoSize);
qPYB = get_QPY(ctx,xQG,yQG-1);
}
else {
qPYB = qPY_PRED;
}
qPY_PRED = (qPYA + qPYB + 1)>>1;
int QPY = ((qPY_PRED + shdr->CuQpDelta + 52+2*sps->QpBdOffset_Y) %
(52 + sps->QpBdOffset_Y)) - sps->QpBdOffset_Y;
tctx->qPYPrime = QPY + sps->QpBdOffset_Y;
int qPiCb = Clip3(-sps->QpBdOffset_C,57, QPY+pps->pic_cb_qp_offset + shdr->slice_cb_qp_offset);
int qPiCr = Clip3(-sps->QpBdOffset_C,57, QPY+pps->pic_cr_qp_offset + shdr->slice_cr_qp_offset);
logtrace(LogTransform,"qPiCb:%d (%d %d), qPiCr:%d (%d %d)\n",
qPiCb, pps->pic_cb_qp_offset, shdr->slice_cb_qp_offset,
qPiCr, pps->pic_cr_qp_offset, shdr->slice_cr_qp_offset);
int qPCb = table8_22(qPiCb);
int qPCr = table8_22(qPiCr);
tctx->qPCbPrime = qPCb + sps->QpBdOffset_C;
tctx->qPCrPrime = qPCr + sps->QpBdOffset_C;
set_QPY(ctx,xQG,yQG, QPY);
tctx->currentQPY = QPY;
logtrace(LogTransform,"qPY(%d,%d)= %d\n",xC,yC,QPY);
}
