音视频编解码技术及实践源码

/*! *********************************************************************** * \file macroblock.c * * \brief * Decode a Macroblock * * \author * Main contributors (see contributors.h for copyright, address and affiliation details) * - Inge Lille-Lang�y <inge.lille-langoy@telenor.com> * - Rickard Sjoberg <rickard.sjoberg@era.ericsson.se> * - Jani Lainema <jani.lainema@nokia.com> * - Sebastian Purreiter <sebastian.purreiter@mch.siemens.de> * - Thomas Wedi <wedi@tnt.uni-hannover.de> * - Detlev Marpe <marpe@hhi.de> * - Gabi Blaettermann <blaetter@hhi.de> * - Ye-Kui Wang <wyk@ieee.org> * - Lowell Winger <lwinger@lsil.com> *********************************************************************** */ #include "contributors.h" #include <math.h> #include <stdlib.h> #include <assert.h> #include <string.h> #include "global.h" #include "mbuffer.h" #include "elements.h" #include "errorconcealment.h" #include "macroblock.h" #include "fmo.h" #include "cabac.h" #include "vlc.h" #include "image.h" #include "mb_access.h" #include "biaridecod.h" #include "transform8x8.h" #if TRACE #define TRACE_STRING(s) strncpy(currSE.tracestring, s, TRACESTRING_SIZE) #else #define TRACE_STRING(s) // do nothing #endif extern int last_dquant; extern ColocatedParams *Co_located; static void SetMotionVectorPredictor (struct img_par *img, short *pmv_x, short *pmv_y, char ref_frame, byte list, char ***refPic, short ****tmp_mv, int block_x, int block_y, int blockshape_x, int blockshape_y); /*! ************************************************************************ * \brief * initializes the current macroblock ************************************************************************ */ void start_macroblock(struct img_par *img,struct inp_par *inp, int CurrentMBInScanOrder) { int i,j,k,l; Macroblock *currMB; // intialization code deleted, see below, StW assert (img->current_mb_nr < img->PicSizeInMbs); currMB = &img->mb_data[img->current_mb_nr]; /* Update coordinates of the current macroblock */ if (img->MbaffFrameFlag) { img->mb_x = (img->current_mb_nr)%((2*img->width)/MB_BLOCK_SIZE); img->mb_y = 2*((img->current_mb_nr)/((2*img->width)/MB_BLOCK_SIZE)); if (img->mb_x % 2) { img->mb_y++; } img->mb_x /= 2; } else { img->mb_x = (img->current_mb_nr)%(img->width/MB_BLOCK_SIZE); img->mb_y = (img->current_mb_nr)/(img->width/MB_BLOCK_SIZE); } /* Define vertical positions */ img->block_y = img->mb_y * BLOCK_SIZE; /* luma block position */ img->pix_y = img->mb_y * MB_BLOCK_SIZE; /* luma macroblock position */ img->pix_c_y = img->mb_y * img->mb_cr_size_y; /* chroma macroblock position */ /* Define horizontal positions */ img->block_x = img->mb_x * BLOCK_SIZE; /* luma block position */ img->pix_x = img->mb_x * MB_BLOCK_SIZE; /* luma pixel position */ img->pix_c_x = img->mb_x * img->mb_cr_size_x; /* chroma pixel position */ // Save the slice number of this macroblock. When the macroblock below // is coded it will use this to decide if prediction for above is possible currMB->slice_nr = img->current_slice_nr; if (img->current_slice_nr >= MAX_NUM_SLICES) { error ("maximum number of supported slices exceeded, please recompile with increased value for MAX_NUM_SLICES", 200); } dec_picture->slice_id[img->mb_y][img->mb_x] = img->current_slice_nr; if (img->current_slice_nr > dec_picture->max_slice_id) { dec_picture->max_slice_id=img->current_slice_nr; } CheckAvailabilityOfNeighbors(img); // Reset syntax element entries in MB struct currMB->qp = img->qp ; currMB->mb_type = 0; currMB->delta_quant = 0; currMB->cbp = 0; currMB->cbp_blk = 0; currMB->c_ipred_mode= DC_PRED_8; //GB for (l=0; l < 2; l++) for (j=0; j < BLOCK_MULTIPLE; j++) for (i=0; i < BLOCK_MULTIPLE; i++) for (k=0; k < 2; k++) currMB->mvd[l][j][i][k] = 0; currMB->cbp_bits = 0; // initialize img->m7 for ABT for (j=0; j<MB_BLOCK_SIZE; j++) for (i=0; i<MB_BLOCK_SIZE; i++) img->m7[i][j] = 0; // store filtering parameters for this MB currMB->LFDisableIdc = img->currentSlice->LFDisableIdc; currMB->LFAlphaC0Offset = img->currentSlice->LFAlphaC0Offset; currMB->LFBetaOffset = img->currentSlice->LFBetaOffset; } /*! ************************************************************************ * \brief * set coordinates of the next macroblock * check end_of_slice condition ************************************************************************ */ int exit_macroblock(struct img_par *img,struct inp_par *inp,int eos_bit) { //! The if() statement below resembles the original code, which tested //! img->current_mb_nr == img->PicSizeInMbs. Both is, of course, nonsense //! In an error prone environment, one can only be sure to have a new //! picture by checking the tr of the next slice header! // printf ("exit_macroblock: FmoGetLastMBOfPicture %d, img->current_mb_nr %d\n", FmoGetLastMBOfPicture(), img->current_mb_nr); img->num_dec_mb++; if (img->num_dec_mb == img->PicSizeInMbs) // if (img->current_mb_nr == FmoGetLastMBOfPicture(currSlice->structure)) { //thb /* if (currSlice->next_header != EOS) currSlice->next_header = SOP; */ //the assert (nal_startcode_follows (img, inp, eos_bit) == TRUE); return TRUE; } // ask for last mb in the slice UVLC else { // printf ("exit_macroblock: Slice %d old MB %d, now using MB %d\n", img->current_slice_nr, img->current_mb_nr, FmoGetNextMBNr (img->current_mb_nr)); img->current_mb_nr = FmoGetNextMBNr (img->current_mb_nr); if (img->current_mb_nr == -1) // End of Slice group, MUST be end of slice { assert (nal_startcode_follows (img, inp, eos_bit) == TRUE); return TRUE; } if(nal_startcode_follows(img, inp, eos_bit) == FALSE) return FALSE; if(img->type == I_SLICE || img->type == SI_SLICE || active_pps->entropy_coding_mode_flag == CABAC) return TRUE; if(img->cod_counter<=0) return TRUE; return FALSE; } } /*! ************************************************************************ * \brief * Interpret the mb mode for P-Frames ************************************************************************ */ void interpret_mb_mode_P(struct img_par *img) { int i; const int ICBPTAB[6] = {0,16,32,15,31,47}; Macroblock *currMB = &img->mb_data[img->current_mb_nr]; int mbmode = currMB->mb_type; #define ZERO_P8x8 (mbmode==5) #define MODE_IS_P8x8 (mbmode==4 || mbmode==5) #define MODE_IS_I4x4 (mbmode==6) #define I16OFFSET (mbmode-7) #define MODE_IS_IPCM (mbmode==31) if(mbmode <4) { currMB->mb_type = mbmode; for (i=0;i<4;i++) { currMB->b8mode[i] = mbmode; currMB->b8pdir[i] = 0; } } else if(MODE_IS_P8x8) { currMB->mb_type = P8x8; img->allrefzero = ZERO_P8x8; } else if(MODE_IS_I4x4) { currMB->mb_type = I4MB; for (i=0;i<4;i++) { currMB->b8mode