/**
This function permits to decode all intra chrominances in a MB.
@param image_Cb Table of current frame.
@param image_Cr Table of current frame.
@param Block Data of the current macroblock.
@param PicWidth Width in macroblocks of the current frame.
@param pps PPS structure of the current video.
@param macro Specifies the availability of the neighbouring macroblock.
@param residu Structure which contains all the residu data of the current macroblock..
@param quantif Table which contains the quantization table.
@param mb4x4_mode is the function vector for intra prediction
*/
void DecodeResidualChroma (unsigned char *image_Cb, unsigned char *image_Cr, const PPS *pps, const RESIDU *residu, const short PicWidthInPix, const W_TABLES *quantif)
{
short DC_coeff [4];
short AC_coeff [16];
//for Cb
if ( residu -> Cbp & 0x30) {
//Initialisation du QP
int QPc = qP_tab [residu -> Qp + pps -> chroma_qp_index_offset];
ict_4x4_dc_chroma(&residu -> ChromaDCLevel_Cb [0], DC_coeff);
rescale_4x4_dc_chr(QPc, DC_coeff, DC_coeff, quantif -> W4x4_Cb_inter);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cb [0], AC_coeff, quantif -> W4x4_Cb_inter);
AC_coeff [0] = DC_coeff [0];
ict_4x4_residual(AC_coeff, image_Cb, PicWidthInPix);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cb [16], AC_coeff,quantif -> W4x4_Cb_inter);
AC_coeff [0] = DC_coeff [1];
ict_4x4_residual(AC_coeff, &image_Cb[4],PicWidthInPix);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cb [32], AC_coeff, quantif -> W4x4_Cb_inter);
AC_coeff [0] = DC_coeff [2];
ict_4x4_residual(AC_coeff, &image_Cb[PicWidthInPix << 2],PicWidthInPix);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cb [48], AC_coeff, quantif -> W4x4_Cb_inter);
AC_coeff [0] = DC_coeff [3];
ict_4x4_residual(AC_coeff, &image_Cb[(1 + PicWidthInPix) << 2],PicWidthInPix);
QPc = qP_tab [residu -> Qp + pps -> second_chroma_qp_index_offset];
ict_4x4_dc_chroma(&residu -> ChromaDCLevel_Cr [0], DC_coeff);
rescale_4x4_dc_chr(QPc, DC_coeff, DC_coeff, quantif -> W4x4_Cr_inter);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cr [0], AC_coeff, quantif -> W4x4_Cr_inter);
AC_coeff [0] = DC_coeff [0];
ict_4x4_residual(AC_coeff, image_Cr,PicWidthInPix);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cr [16], AC_coeff, quantif -> W4x4_Cr_inter);
AC_coeff [0] = DC_coeff [1];
ict_4x4_residual(AC_coeff, &image_Cr[4],PicWidthInPix);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cr [32], AC_coeff, quantif -> W4x4_Cr_inter);
AC_coeff [0] = DC_coeff [2];
ict_4x4_residual(AC_coeff, &image_Cr[PicWidthInPix << 2],PicWidthInPix);
rescale_4x4_residual(QPc, &residu -> ChromaACLevel_Cr [48], AC_coeff, quantif -> W4x4_Cr_inter);
AC_coeff [0] = DC_coeff [3];
ict_4x4_residual(AC_coeff, &image_Cr[(1 + PicWidthInPix) << 2],PicWidthInPix);
}
}
/**
Rescale coefficent for Scoeff prediction for chroma
*/
void ScoeffSRescaleChr4x4(RESIDU *CurrResidu, const PPS* Pps, const W_TABLES *Quantif)
{
short BaseDC_coeff [4];
short BqP = (short) (CurrResidu -> Qp + Pps -> chroma_qp_index_offset);
short BQPc = qP_tab [BqP];
ict_4x4_dc_chroma(&CurrResidu -> ChromaDCLevel_Cb [0], BaseDC_coeff);
rescale_4x4_dc_chr(BQPc, BaseDC_coeff, BaseDC_coeff, Quantif -> W4x4_Cb_inter);
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cb [0], &CurrResidu -> ChromaACLevel_Cb [0], Quantif -> W4x4_Cb_inter);
CurrResidu -> ChromaACLevel_Cb [0] = BaseDC_coeff [0];
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cb [16], &CurrResidu -> ChromaACLevel_Cb [16], Quantif -> W4x4_Cb_inter);
CurrResidu -> ChromaACLevel_Cb [16] = BaseDC_coeff [1];
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cb [32], &CurrResidu -> ChromaACLevel_Cb [32], Quantif -> W4x4_Cb_inter);
CurrResidu -> ChromaACLevel_Cb [32] = BaseDC_coeff [2];
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cb [48], &CurrResidu -> ChromaACLevel_Cb [48], Quantif -> W4x4_Cb_inter);
CurrResidu -> ChromaACLevel_Cb [48] = BaseDC_coeff [3];
//Cr
BqP = (short) (CurrResidu -> Qp + Pps -> second_chroma_qp_index_offset);
BQPc = qP_tab [BqP];
ict_4x4_dc_chroma(&CurrResidu -> ChromaDCLevel_Cr [0], BaseDC_coeff);
rescale_4x4_dc_chr(BQPc, BaseDC_coeff, BaseDC_coeff, Quantif -> W4x4_Cr_inter);
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cr [0], &CurrResidu -> ChromaACLevel_Cr [0], Quantif -> W4x4_Cr_inter);
CurrResidu -> ChromaACLevel_Cr [0] = BaseDC_coeff [0];
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cr [16], &CurrResidu -> ChromaACLevel_Cr [16], Quantif -> W4x4_Cr_inter);
CurrResidu -> ChromaACLevel_Cr [16] = BaseDC_coeff [1];
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cr [32], &CurrResidu -> ChromaACLevel_Cr [32], Quantif -> W4x4_Cr_inter);
CurrResidu -> ChromaACLevel_Cr [32] = BaseDC_coeff [2];
rescale_4x4_residual(BQPc, &CurrResidu -> ChromaACLevel_Cr [48], &CurrResidu -> ChromaACLevel_Cr [48], Quantif -> W4x4_Cr_inter);
CurrResidu -> ChromaACLevel_Cr [48] = BaseDC_coeff [3];
}
