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Added chroma compression

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This commit is contained in:
Marko Viitanen 2013-03-11 16:26:09 +02:00
parent 57f892f1d8
commit 892a31eeaf
5 changed files with 205 additions and 67 deletions
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10
src/encmain.c
View file

@ -58,7 +58,9 @@
config *cfg = NULL; /* Global configuration */
FILE *input = NULL;
FILE *output = NULL;
#ifdef _DEBUG
FILE *recout = fopen("encrec.yuv","wb");
#endif
encoder_control* encoder = (encoder_control*)malloc(sizeof(encoder_control));;
/* Handle configuration */
@ -127,7 +129,7 @@
/* input init (ToDo: read from commandline / config) */
encoder->bitdepth = 8;
encoder->frame = 0;
encoder->QP = 35;
encoder->QP = 25;
encoder->in.video_format = FORMAT_420;
init_encoder_input(&encoder->in, input, cfg->width, cfg->height);
@ -140,10 +142,12 @@
fread(encoder->in.cur_pic.vData, cfg->width*cfg->height>>2,1,input);
encode_one_frame(encoder);
/* Write reconstructed frame out */
#ifdef _DEBUG
/* Write reconstructed frame out */
fwrite(encoder->in.cur_pic.yRecData,cfg->width*cfg->height,1,recout);
fwrite(encoder->in.cur_pic.uRecData,cfg->width*cfg->height>>2,1,recout);
fwrite(encoder->in.cur_pic.vRecData,cfg->width*cfg->height>>2,1,recout);
#endif
//printf("[%d] %c-frame\n", encoder->frame, "IPB"[encoder->in.cur_pic.type%3]);
encoder->frame++;
}
@ -153,7 +157,9 @@
fclose(input);
fclose(output);
#ifdef _DEBUG
fclose(recout);
#endif
/* Deallocating */
config_destroy(cfg);

201
src/encoder.c
View file

@ -10,7 +10,7 @@
Encoder main level
*/
/* Suppress some windows warnings */
/* Suppress some visual studio warnings */
#ifdef WIN32
#define _CRT_SECURE_NO_WARNINGS
#endif
@ -690,24 +690,19 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
{
cur_CU->type = CU_INTRA;
}
/* coding_unit( x0, y0, log2CbSize ) */
/* prediction_unit 2Nx2N*/
//if !intra PREDMODE
/* if depth = MAX_DEPTH */
//PartSize
/* Signal PartSize on max depth */
if(depth == MAX_DEPTH)
{
cabac.ctx = &g_PartSizeSCModel;
CABAC_BIN(&cabac, 1, "PartSize");
}
/*end partsize*/
//If MODE_INTRA
/*end partsize*/
if(cur_CU->type == CU_INTRA)
{
uint8_t intraPredMode = 1;
uint8_t intraPredModeChroma = 36; //Chroma derived from luma
uint8_t intraPredModeChroma = 36; /* 36 = Chroma derived from luma */
int8_t intraPreds[3] = {-1, -1, -1};
int8_t mpmPred = -1;
int i;
@ -730,10 +725,10 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
break;
}
}
//For each part {
/* For each part { */
cabac.ctx = &g_IntraModeSCModel;
CABAC_BIN(&cabac,(mpmPred==-1)?0:1,"IntraPred");
//} End for each part
/*} End for each part */
/* Intrapredmode signaling
If found from predictors, we can simplify signaling
@ -744,7 +739,7 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
if(mpmPred!=0)
CABAC_BIN_EP(&cabac, (mpmPred==1)?0:1, "intraPredMode");
}
else //Else we signal the full predmode
else /* Else we signal the "full" predmode */
{
int8_t intraPredModeTemp = intraPredMode;
if (intraPreds[0] > intraPreds[1])
@ -769,23 +764,23 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
/* If we have chroma, signal it */
if(encoder->in.video_format != FORMAT_400)
{
//Chroma intra prediction
/* Chroma intra prediction */
cabac.ctx = &g_ChromaPredSCModel[0];
CABAC_BIN(&cabac,((intraPredModeChroma!=36)?1:0),"IntraPredChroma");
//If not copied from luma, signal it
/* If not copied from luma, signal it */
if(intraPredModeChroma!=36)
{
int8_t intraPredModeChromaTemp = intraPredModeChroma;
/* Default chroma predictors */
uint32_t allowedChromaDir[ 5 ] = { 0, 26, 10, 1, 36 };
//If intra is the same as one of the default predictors, replace it
/* If intra is the same as one of the default predictors, replace it */
for(i = 0; i < 4; i++ )
{
if( intraPredMode == allowedChromaDir[i] )
{
allowedChromaDir[i] = 34; // VER+8 mode
allowedChromaDir[i] = 34; /* VER+8 mode */
break;
}
}
@ -807,7 +802,7 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
/* Coeff */
/* Transform tree */
cabac.ctx = &g_TransSubdivSCModel[0]; /* //uiLog2TransformBlockSize */
cabac.ctx = &g_TransSubdivSCModel[0]; /* uiLog2TransformBlockSize */
CABAC_BIN(&cabac,0,"TransformSubdivFlag");
/* We don't subdiv and we have 64>>depth transform size */
@ -816,19 +811,29 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
uint8_t CbY = 0,CbU = 0,CbV = 0;
/*
Quant and transform here...
Quant and transform here...
*/
int16_t block[32*32];
int16_t pre_quant_coeff[32*32];
int16_t coeff[32*32];
int16_t coeffU[16*16];
int16_t coeffV[16*16];
uint8_t *base = &encoder->in.cur_pic.yData[xCtb*(LCU_WIDTH>>(MAX_DEPTH)) + (yCtb*(LCU_WIDTH>>(MAX_DEPTH)))*encoder->in.width];
uint8_t *baseU = &encoder->in.cur_pic.uData[xCtb*(LCU_WIDTH>>(MAX_DEPTH+1)) + (yCtb*(LCU_WIDTH>>(MAX_DEPTH+1)))*(encoder->in.width>>1)];
uint8_t *baseV = &encoder->in.cur_pic.vData[xCtb*(LCU_WIDTH>>(MAX_DEPTH+1)) + (yCtb*(LCU_WIDTH>>(MAX_DEPTH+1)))*(encoder->in.width>>1)];
uint32_t width = LCU_WIDTH>>depth;
/* INTRAPREDICTION */
/* ToDo: split to a function */
int16_t pred[32*32];
int16_t dcpred = intra_getDCPred(&encoder->in.cur_pic, xCtb, yCtb, depth);
int16_t predU[16*16];
int16_t predV[16*16];
int16_t dcpred = intra_getDCPred(encoder->in.cur_pic.yRecData,encoder->in.width, xCtb, yCtb, depth,0);
int16_t dcpredU = intra_getDCPred(encoder->in.cur_pic.uRecData,encoder->in.width>>1, xCtb, yCtb, depth,1);
int16_t dcpredV = intra_getDCPred(encoder->in.cur_pic.vRecData,encoder->in.width>>1, xCtb, yCtb, depth,1);
uint8_t *recbase = &encoder->in.cur_pic.yRecData[xCtb*(LCU_WIDTH>>(MAX_DEPTH)) + (yCtb*(LCU_WIDTH>>(MAX_DEPTH)))*encoder->in.width];
uint8_t *recbaseU = &encoder->in.cur_pic.uRecData[xCtb*(LCU_WIDTH>>(MAX_DEPTH+1)) + (yCtb*(LCU_WIDTH>>(MAX_DEPTH+1)))*(encoder->in.width>>1)];
uint8_t *recbaseV = &encoder->in.cur_pic.vRecData[xCtb*(LCU_WIDTH>>(MAX_DEPTH+1)) + (yCtb*(LCU_WIDTH>>(MAX_DEPTH+1)))*(encoder->in.width>>1)];
/* Fill prediction */
for(y = 0; y < LCU_WIDTH>>depth; y++)
{
@ -837,6 +842,14 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
pred[x+y*32] = dcpred;
}
}
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
{
predU[x+y*16] = dcpredU;
predV[x+y*16] = dcpredV;
}
}
/* Get residual by subtracting prediction */
i = 0;
@ -847,14 +860,35 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
block[i++]=((int16_t)base[x+y*encoder->in.width])-pred[x+y*32];
}
}
memset(pre_quant_coeff,0,sizeof(int16_t)*32*32);
memset(coeff,0,sizeof(int16_t)*32*32);
/* Transform and quant residual to coeffs */
transform2d(block,pre_quant_coeff,LCU_WIDTH>>depth,0);
quant(encoder,pre_quant_coeff,coeff, width, width, 0);
/* U */
//memset(block, 0, sizeof(int16_t)*32*32);
//memset(pre_quant_coeff, 0, sizeof(int16_t)*32*32);
i = 0;
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
{
block[i++]=((int16_t)baseU[x+y*(encoder->in.width>>1)])-predU[x+y*16];
}
}
transform2d(block,pre_quant_coeff,LCU_WIDTH>>(depth+1),0);
quant(encoder,pre_quant_coeff,coeffU, width>>1, width>>1, 2);
/* V */
i = 0;
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
{
block[i++]=((int16_t)baseV[x+y*(encoder->in.width>>1)])-predV[x+y*16];
}
}
transform2d(block,pre_quant_coeff,LCU_WIDTH>>(depth+1),0);
quant(encoder,pre_quant_coeff,coeffV, width>>1, width>>1, 3);
/* Check for non-zero coeffs */
for(i = 0; (uint32_t)i < width*width; i++)
{
@ -866,6 +900,26 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
}
}
for(i = 0; (uint32_t)i < width*width>>2; i++)
{
if(coeffU[i] != 0)
{
/* Found one, we can break here */
CbU = 1;
break;
}
}
for(i = 0; (uint32_t)i < width*width>>2; i++)
{
if(coeffV[i] != 0)
{
/* Found one, we can break here */
CbV = 1;
break;
}
}
/* if non-zero coeffs */
if(CbY)
{
@ -896,17 +950,84 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
}
}
}
if(CbU)
{
/* RECONSTRUCT for predictions */
dequant(encoder,coeffU,pre_quant_coeff,width>>1, width>>1);
itransform2d(block,pre_quant_coeff,LCU_WIDTH>>(depth+1),0);
i = 0;
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
{
int16_t val = block[i++]+predU[x+y*16];
//ToDo: support 10+bits
recbaseU[x+y*(encoder->in.width>>1)] = (uint8_t)CLIP(0,255,val);
}
}
/* END RECONTRUCTION */
}
/* without coeffs, we only use the prediction */
else
{
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
{
recbaseU[x+y*(encoder->in.width>>1)] = (uint8_t)CLIP(0,255,predU[x+y*16]);
}
}
}
if(CbV)
{
/* RECONSTRUCT for predictions */
dequant(encoder,coeffV,pre_quant_coeff,width>>1, width>>1);
itransform2d(block,pre_quant_coeff,LCU_WIDTH>>(depth+1),0);
i = 0;
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
{
int16_t val = block[i++]+predV[x+y*16];
//ToDo: support 10+bits
recbaseV[x+y*(encoder->in.width>>1)] = (uint8_t)CLIP(0,255,val);
}
}
/* END RECONTRUCTION */
}
/* without coeffs, we only use the prediction */
else
{
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
{
recbaseV[x+y*(encoder->in.width>>1)] = (uint8_t)CLIP(0,255,predV[x+y*16]);
}
}
}
/*
if(xCtb && yCtb)
{
intra_DCPredFiltering(recbaseU,(encoder->in.width>>1),recbaseU,(encoder->in.width>>1),LCU_WIDTH>>(depth+1),LCU_WIDTH>>(depth+1));
intra_DCPredFiltering(recbaseV,(encoder->in.width>>1),recbaseV,(encoder->in.width>>1),LCU_WIDTH>>(depth+1),LCU_WIDTH>>(depth+1));
}
*/
/* END INTRAPREDICTION */
/* Signal if chroma data is present */
if(encoder->in.video_format != FORMAT_400)
{
/* Non-zero chroma U Tcoeffs */
cabac.ctx = &g_QtCbfSCModelU[0];
CABAC_BIN(&cabac,CbU,"cbf_chroma_u");
/* Non-zero chroma V Tcoeffs */
/* Using the same ctx as before */
cabac.ctx = &g_QtCbfSCModelU[0]; /*<- */
CABAC_BIN(&cabac,CbU,"cbf_chroma_u");/* \ */
/* | */
/* Non-zero chroma V Tcoeffs */ /* | */
/* NOTE: Using the same ctx as before _ / */
CABAC_BIN(&cabac,CbV,"cbf_chroma_v");
}
@ -917,17 +1038,18 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
/* CoeffNxN */
/* Residual Coding */
if(CbY)
{
{
encode_CoeffNxN(encoder,coeff, width, 0);
}
if(CbU)
{
encode_CoeffNxN(encoder,coeff, width>>1, 1);
encode_CoeffNxN(encoder,coeffU, width>>1, 2);
}
if(CbV)
{
encode_CoeffNxN(encoder,coeff, width>>1, 2);
encode_CoeffNxN(encoder,coeffV, width>>1, 2);
}
/* end Residual Coding */
}
/* end Transform tree */
@ -954,7 +1076,7 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
}
if(encoder->in.video_format != FORMAT_400)
{
//Cb
/* Cb */
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
@ -963,7 +1085,7 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
}
}
//Cr
/* Cr */
for(y = 0; y < LCU_WIDTH>>(depth+1); y++)
{
for(x = 0; x < LCU_WIDTH>>(depth+1); x++)
@ -982,7 +1104,6 @@ void encode_coding_tree(encoder_control* encoder,uint16_t xCtb,uint16_t yCtb, ui
printf("UNHANDLED TYPE!\r\n");
exit(1);
}
//endif
/* end prediction unit */
/* end coding_unit */
@ -1021,7 +1142,7 @@ void encode_CoeffNxN(encoder_control* encoder,int16_t* coeff, uint8_t width, uin
memset(sig_coeffgroup_flag,0,sizeof(uint32_t)*64);
/* Count non-zero coeffs */
for(i = 0; (uint32_t)i < width*width; i++)
for(i = 0; i < width*width; i++)
{
if(coeff[i] != 0)
{
@ -1225,28 +1346,30 @@ void encode_lastSignificantXY(encoder_control* encoder,uint8_t lastpos_x, uint8_
int uiGroupIdxX = g_uiGroupIdx[lastpos_x];
int uiGroupIdxY = g_uiGroupIdx[lastpos_y];
int last_x,last_y,i;
cabac_ctx* basectxX = (type?g_CuCtxLastX_chroma:g_CuCtxLastX_luma);
cabac_ctx* basectxY = (type?g_CuCtxLastY_chroma:g_CuCtxLastY_luma);
/* Last X binarization */
for(last_x = 0; last_x < uiGroupIdxX ; last_x++)
{
cabac.ctx = &g_CuCtxLastX_luma[offset_x+(last_x>>shift_x)];
cabac.ctx = &basectxX[offset_x+(last_x>>shift_x)];
CABAC_BIN(&cabac,1,"LastSignificantX");
}
if(uiGroupIdxX < g_uiGroupIdx[width-1])
{
cabac.ctx = &g_CuCtxLastX_luma[offset_x+(last_x>>shift_x)];
cabac.ctx = &basectxX[offset_x+(last_x>>shift_x)];
CABAC_BIN(&cabac,0,"LastSignificantX");
}
/* Last Y binarization */
for(last_y = 0; last_y < uiGroupIdxY ; last_y++)
{
cabac.ctx = &g_CuCtxLastY_luma[offset_y+(last_y>>shift_y)];
cabac.ctx = &basectxY[offset_y+(last_y>>shift_y)];
CABAC_BIN(&cabac,1,"LastSignificantY");
}
if(uiGroupIdxY < g_uiGroupIdx[height-1])
{
cabac.ctx = &g_CuCtxLastY_luma[offset_y+(last_y>>shift_y)];
cabac.ctx = &basectxY[offset_y+(last_y>>shift_y)];
CABAC_BIN(&cabac,0,"LastSignificantY");
}

52
src/intra.c
View file

@ -82,12 +82,12 @@ int8_t intra_getBlockMode(picture* pic,uint32_t xCtb, uint32_t yCtb, uint8_t dep
\param depth current CU depth
\returns DC prediction or -1 if not available
*/
int16_t intra_getDCPred(picture* pic,uint32_t xCtb, uint32_t yCtb, uint8_t depth)
int16_t intra_getDCPred(uint8_t* pic, uint16_t picwidth,uint32_t xCtb, uint32_t yCtb, uint8_t depth, uint8_t chroma)
{
int32_t i, iSum = 0;
int16_t pDcVal = 1<<(g_uiBitDepth-1);
int32_t width = (LCU_WIDTH>>depth);
int32_t SCUwidth = (LCU_WIDTH>>MAX_DEPTH);
int32_t width = (LCU_WIDTH>>(depth+chroma));
int32_t SCUwidth = (LCU_WIDTH>>(MAX_DEPTH+chroma));
int32_t xpos = SCUwidth*xCtb;
int32_t ypos = SCUwidth*yCtb;
int32_t LCU_xpos = xpos - (xpos%LCU_WIDTH);
@ -100,48 +100,35 @@ int16_t intra_getDCPred(picture* pic,uint32_t xCtb, uint32_t yCtb, uint8_t depth
if (bAbove)
{
add = (ypos-1)*pic->width;
add = (ypos-1)*picwidth;
for (i = xpos+add; i < xpos+width+add ; i++)
{
iSum += pic->yRecData[i];
iSum += pic[i];
}
}
else if (bLeft)
{
iSum += pic->yRecData[ypos*pic->width+xpos-1]*width;
iSum += pic[ypos*picwidth+xpos-1]*width;
}
if (bLeft)
{
add = xpos-1;
for (i = ypos*pic->width+add ; i < (ypos+width)*pic->width+add ; i+=pic->width)
for (i = ypos*picwidth+add ; i < (ypos+width)*picwidth+add ; i+=picwidth)
{
iSum += pic->yRecData[i];
iSum += pic[i];
}
}
else if (bAbove)
{
iSum += pic->yRecData[(ypos-1)*pic->width+xpos]*width;
iSum += pic[(ypos-1)*picwidth+xpos]*width;
}
//if (bAbove && bLeft)
if (bAbove || bLeft)
{
pDcVal = (iSum + width) / (width + width);
}
/*
else if (bAbove)
{
pDcVal = (iSum + width/2) / width;
}
else if (bLeft)
{
pDcVal = (iSum + width/2) / width;
}
*/
return pDcVal;
}
@ -207,6 +194,27 @@ int8_t intra_getDirLumaPredictor(picture* pic,uint32_t xCtb, uint32_t yCtb, uint
return 1;
}
void intra_DCPredFiltering(uint8_t* pSrc, int32_t iSrcStride, uint8_t* rpDst, int32_t iDstStride, int32_t iWidth, int32_t iHeight )
{
uint8_t* pDst = rpDst;
int32_t x, y, iDstStride2, iSrcStride2;
// boundary pixels processing
pDst[0] = ((pSrc[-iSrcStride] + pSrc[-1] + 2 * pDst[0] + 2) >> 2);
for ( x = 1; x < iWidth; x++ )
{
pDst[x] = ((pSrc[x - iSrcStride] + 3 * pDst[x] + 2) >> 2);
}
for ( y = 1, iDstStride2 = iDstStride, iSrcStride2 = iSrcStride-1; y < iHeight; y++, iDstStride2+=iDstStride, iSrcStride2+=iSrcStride )
{
pDst[iDstStride2] = ((pSrc[iSrcStride2] + 3 * pDst[iDstStride2] + 2) >> 2);
}
return;
}
/*! \brief Function for deriving planar intra prediction.
\param pic picture to use
\param xCtb x CU position (smallest CU)

3
src/intra.h
View file

@ -15,7 +15,8 @@
void intra_setBlockMode(picture* pic,uint32_t xCtb, uint32_t yCtb, uint8_t depth, uint8_t mode);
int8_t intra_getBlockMode(picture* pic,uint32_t xCtb, uint32_t yCtb, uint8_t depth);
int16_t intra_getDCPred(picture* pic,uint32_t xCtb, uint32_t yCtb, uint8_t depth);
int16_t intra_getDCPred(uint8_t* pic, uint16_t picwidth,uint32_t xCtb, uint32_t yCtb, uint8_t depth, uint8_t chroma);
int8_t intra_getDirLumaPredictor(picture* pic,uint32_t xCtb, uint32_t yCtb, uint8_t depth, int8_t* preds);
void intra_DCPredFiltering(uint8_t* pSrc, int32_t iSrcStride, uint8_t* rpDst, int32_t iDstStride, int32_t iWidth, int32_t iHeight );
#endif

6
src/transform.c
View file

@ -597,7 +597,7 @@ void transform2d(int16_t *block,int16_t *coeff, int8_t blockSize, int8_t uiMode)
int32_t shift_1st = g_aucConvertToBit[blockSize] + 1 + g_uiBitIncrement; // log2(iWidth) - 1 + g_uiBitIncrement
int32_t shift_2nd = g_aucConvertToBit[blockSize] + 8; // log2(iHeight) + 6
short tmp[ 64 * 64 ];
int16_t tmp[32*32];
/*
if(blockSize== 4)
{
@ -648,7 +648,7 @@ void itransform2d(int16_t *block,int16_t *coeff, int8_t blockSize, int8_t uiMode
{
int32_t shift_1st = 7;
int32_t shift_2nd = 12 - (g_uiBitDepth-8);
int16_t tmp[ 64*64];
int16_t tmp[32*32];
if( blockSize == 8)
{
@ -726,7 +726,7 @@ void quant(encoder_control* encoder, int16_t* pSrc, int16_t* pDes, /*int32_t** p
int32_t iTransformShift = /*MAX_TR_DYNAMIC_RANGE*/15 - uiBitDepth - uiLog2TrSize; // Represents scaling through forward transform
int32_t iQBits = QUANT_SHIFT + /*cQpBase.m_iPer +*/qpScaled/6 + iTransformShift;
int32_t iAdd = ((encoder->in.cur_pic.type == NAL_IDR_SLICE || encoder->in.cur_pic.type == 0) ? 171 : 85) << (iQBits-9);
int32_t iAdd = ((encoder->in.cur_pic.slicetype == SLICE_I) ? 171 : 85) << (iQBits-9);
int32_t qBits8 = iQBits-8;
for( n = 0; n < iWidth*iHeight; n++ )