slice.c

H.264视频编解码的标准测试模型

        //---------------------------------------------------------------------
        img->field_mode = 1;  // MB coded as field
        img->top_field = 1;   // Set top field to 1
        img->buf_cycle <<= 1;
        input->num_ref_frames <<= 1;
        img->num_ref_idx_l0_active <<= 1;
        img->num_ref_idx_l0_active += 1;
        start_macroblock (CurrentMbAddr, TRUE);
        

        rdopt = &rddata_top_field_mb; // store data in top frame MB 
//        TopFieldIsSkipped = 0;        // set the top field MB skipped flag to 0
        encode_one_macroblock ();     // code the MB as frame
        FieldRDCost = rdopt->min_rdcost;
        //***   Top MB coded as field MB ***//
        //Rate control
        img->bot_MB = 1;//for Rate control

        img->top_field = 0;   // Set top field to 0
        start_macroblock (CurrentMbAddr+1, TRUE);
        rdopt = &rddata_bot_field_mb; // store data in top frame MB 
        encode_one_macroblock ();     // code the MB as frame
        FieldRDCost += rdopt->min_rdcost;
        //***   Bottom MB coded as field MB ***//
      }

      //Rate control
      img->write_macroblock_frame = 0;  //Rate control

      //=========== decide between frame/field MB pair ============
      //-----------------------------------------------------------
      if ((input->MbInterlace == ADAPTIVE_CODING) && (FrameRDCost < FieldRDCost))
      {
        img->field_mode = 0;
        img->buf_cycle >>= 1;
        input->num_ref_frames >>= 1;
        MBPairIsField = 0;
        img->num_ref_idx_l0_active -= 1;
        img->num_ref_idx_l0_active >>= 1;
        
        //Rate control
        img->write_macroblock_frame = 1;  //for Rate control
      }
      else
      {
        img->field_mode = 1;
        MBPairIsField = 1;
      }
      
      //Rate control
      img->write_macroblock = 1;//Rate control 
      
      if (MBPairIsField)
        img->top_field = 1;
      else
        img->top_field = 0;
      
      //Rate control
      img->bot_MB = 0;// for Rate control

      // go back to the Top MB in the MB pair
      start_macroblock (CurrentMbAddr, img->field_mode);
      
      rdopt =  img->field_mode ? &rddata_top_field_mb : &rddata_top_frame_mb;
      copy_rdopt_data (0);  // copy the MB data for Top MB from the temp buffers
      write_one_macroblock (1);     // write the Top MB data to the bitstream
      terminate_macroblock (&end_of_slice, &recode_macroblock);     // done coding the Top MB 

      if (recode_macroblock == FALSE)       // The final processing of the macroblock has been done
      {
        CurrentMbAddr = FmoGetNextMBNr (CurrentMbAddr);
        if (CurrentMbAddr == -1)   // end of slice
        {
          end_of_slice = TRUE;
        }
        NumberOfCodedMBs++;       // only here we are sure that the coded MB is actually included in the slice
        proceed2nextMacroblock ();


        //Rate control
        img->bot_MB = 1;//for Rate control
        // go to the Bottom MB in the MB pair
        img->top_field = 0;
        start_macroblock (CurrentMbAddr, img->field_mode);
        
        rdopt = img->field_mode ? &rddata_bot_field_mb : &rddata_bot_frame_mb;
        copy_rdopt_data (1);  // copy the MB data for Bottom MB from the temp buffers
        
        write_one_macroblock (0);     // write the Bottom MB data to the bitstream
        terminate_macroblock (&end_of_slice, &recode_macroblock);     // done coding the Top MB 
        if (recode_macroblock == FALSE)       // The final processing of the macroblock has been done
        {
          CurrentMbAddr = FmoGetNextMBNr (CurrentMbAddr);
          if (CurrentMbAddr == -1)   // end of slice
          {
            end_of_slice = TRUE;
          }
          NumberOfCodedMBs++;       // only here we are sure that the coded MB is actually included in the slice
          proceed2nextMacroblock ();
        }
        else
        {
          //Go back to the beginning of the macroblock pair to recode it
          img->current_mb_nr = FmoGetPreviousMBNr(img->current_mb_nr);
          img->current_mb_nr = FmoGetPreviousMBNr(img->current_mb_nr);
          if(img->current_mb_nr == -1 )   // The first MB of the slice group  is too big,
            // which means it's impossible to encode picture using current slice bits restriction
          {
            snprintf (errortext, ET_SIZE, "Error encoding first MB with specified parameter, bits of current MB may be too big");
            error (errortext, 300);
          }
        }
        
      }

      else
      {
        //!Go back to the previous MB to recode it
        img->current_mb_nr = FmoGetPreviousMBNr(img->current_mb_nr);
        if(img->current_mb_nr == -1 )   // The first MB of the slice group  is too big,
                                        // which means it's impossible to encode picture using current slice bits restriction
        {
          snprintf (errortext, ET_SIZE, "Error encoding first MB with specified parameter, bits of current MB may be too big");
          error (errortext, 300);
        }
      }

      
      
      if (MBPairIsField)    // if MB Pair was coded as field the buffer size variables back to frame mode
      {
        img->buf_cycle >>= 1;
        input->num_ref_frames >>= 1;
        img->num_ref_idx_l0_active -= 1;
        img->num_ref_idx_l0_active >>= 1;
      }

      img->field_mode = img->top_field = 0; // reset to frame mode
      
      if (CurrentMbAddr == FmoGetLastCodedMBOfSliceGroup (FmoMB2SliceGroup (CurrentMbAddr)))
        end_of_slice = TRUE;        // just in case it doesn't get set in terminate_macroblock
    }
  }  
/*
  // Tian Dong: June 7, 2002 JVT-B042
  // Restore the short_used
  if (input->NumFramesInELSubSeq)
    {
      fb->short_used = short_used;
    }
*/
  terminate_slice ( (NumberOfCodedMBs+TotalCodedMBs >= (int)img->PicSizeInMbs) );
  return NumberOfCodedMBs;
}



/*!
 ************************************************************************
 * \brief
 *    Initializes the parameters for a new slice and
 *     allocates the memory for the coded slice in the Picture structure
 *  \par Side effects:
 *      Adds slice/partition header symbols to the symbol buffer
 *      increments Picture->no_slices, allocates memory for the
 *      slice, sets img->currSlice
 ************************************************************************
 */
static void init_slice (int start_mb_addr)
{
  int i;
  Picture *currPic = img->currentPicture;
  DataPartition *dataPart;
  Bitstream *currStream;
  Slice *currSlice;

  img->current_mb_nr = start_mb_addr;

  // Allocate new Slice in the current Picture, and set img->currentSlice
  assert (currPic != NULL);
  currPic->no_slices++;
  
  if (currPic->no_slices >= MAXSLICEPERPICTURE)
    error ("Too many slices per picture, increase MAXSLICEPERPICTURE in global.h.", -1);

  currPic->slices[currPic->no_slices-1] = malloc_slice();
  currSlice = currPic->slices[currPic->no_slices-1];

  img->currentSlice = currSlice;

  currSlice->picture_id = img->tr % 256;
  currSlice->qp = img->qp;
  currSlice->start_mb_nr = start_mb_addr;
  currSlice->slice_too_big = dummy_slice_too_big;

  for (i = 0; i < currSlice->max_part_nr; i++)
  {
    dataPart = &(currSlice->partArr[i]);
    if (input->symbol_mode == UVLC)
      dataPart->writeSyntaxElement = writeSyntaxElement_UVLC;
    else
      dataPart->writeSyntaxElement = writeSyntaxElement_CABAC;
    
    currStream = dataPart->bitstream;
    currStream->bits_to_go = 8;
    currStream->byte_pos = 0;
    currStream->byte_buf = 0;
  }

  img->num_ref_idx_l0_active = active_pps->num_ref_idx_l0_active_minus1 + 1; 
  img->num_ref_idx_l1_active = active_pps->num_ref_idx_l1_active_minus1 + 1;

  // generate reference picture lists
  init_lists(img->type, img->structure);

  // assign list 0 size from list size
  img->num_ref_idx_l0_active = listXsize[0];
  img->num_ref_idx_l1_active = listXsize[1];
  
  // code now also considers fields. Issue whether we should account this within the appropriate input params directly
  if ((img->type == P_SLICE || img->type == SP_SLICE) && input->P_List0_refs)
  {
    img->num_ref_idx_l0_active = min(img->num_ref_idx_l0_active, input->P_List0_refs * ((img->structure !=0) + 1));
    listXsize[0] = min(listXsize[0], input->P_List0_refs * ((img->structure !=0) + 1));  
  }
  if (img->type == B_SLICE )
  {
    if (input->B_List0_refs)
    {
      img->num_ref_idx_l0_active = min(img->num_ref_idx_l0_active, input->B_List0_refs * ((img->structure !=0) + 1));
      listXsize[0] = min(listXsize[0], input->B_List0_refs * ((img->structure !=0) + 1));  
    }
    if (input->B_List1_refs)
    {
      
      img->num_ref_idx_l1_active = min(img->num_ref_idx_l1_active, input->B_List1_refs * ((img->structure !=0) + 1));
      listXsize[1] = min(listXsize[1], input->B_List1_refs * ((img->structure !=0) + 1));  
    }
  }

  //Perform memory management based on poc distances for PyramidCoding
  if (img->nal_reference_idc  && input->PyramidCoding && input->PocMemoryManagement && dpb.ref_frames_in_buffer==active_sps->num_ref_frames)
  {    
    poc_based_ref_management(img->frame_num);
  }

  if (input->EnableOpenGOP)
  {
    for (i = 0; i<listXsize[0]; i++)
    {    
      if (listX[0][i]->poc < img->last_valid_reference && img->ThisPOC > img->last_valid_reference)      
      {
        listXsize[0] = img->num_ref_idx_l0_active = max(1,i);
        break;
      }
    }
    
    for (i = 0; i<listXsize[1]; i++)
    {
      if (listX[1][i]->poc < img->last_valid_reference && img->ThisPOC > img->last_valid_reference)
      {
        listXsize[1] = img->num_ref_idx_l1_active = max(1,i);
        break;
      }
    }
  }

  init_ref_pic_list_reordering();

  //Perform reordering based on poc distances for PyramidCoding
  //if (img->type==P_SLICE && input->PyramidCoding && input->PyramidRefReorder)
  if (img->type==P_SLICE && input->PyramidRefReorder)
  {
    
    int i, num_ref;

    alloc_ref_pic_list_reordering_buffer(currSlice);
    
    if ((img->type != I_SLICE) && (img->type !=SI_SLICE))
    {
      for (i=0; i<img->num_ref_idx_l0_active + 1; i++)
      {
        currSlice->reordering_of_pic_nums_idc_l0[i] = 3;
        currSlice->abs_diff_pic_num_minus1_l0[i] = 0;
        currSlice->long_term_pic_idx_l0[i] = 0;
      }
      
      if (img->type == B_SLICE)
      {
        for (i=0; i<img->num_ref_idx_l1_active + 1; i++)
        {
          currSlice->reordering_of_pic_nums_idc_l1[i] = 3;
          currSlice->abs_diff_pic_num_minus1_l1[i] = 0;
          currSlice->long_term_pic_idx_l1[i] = 0;
        }
      }
    }
    
    if ((img->type != I_SLICE) && (img->type !=SI_SLICE))
    {
      num_ref = img->num_ref_idx_l0_active;
      poc_ref_pic_reorder(listX[LIST_0], 
                          num_ref, 
                          currSlice->reordering_of_pic_nums_idc_l0, 
                          currSlice->abs_diff_pic_num_minus1_l0, 
                          currSlice->long_term_pic_idx_l0, 0, LIST_0);
      
      //reference picture reordering
      reorder_ref_pic_list(listX[LIST_0], &listXsize[LIST_0], 
                           img->num_ref_idx_l0_active - 1, 
                           currSlice->reordering_of_pic_nums_idc_l0, 
                           currSlice->abs_diff_pic_num_minus1_l0, 
                           currSlice->long_term_pic_idx_l0);
      
		// This is not necessary since order is already poc based...  
      if (img->type == B_SLICE)
      {
        num_ref = img->num_ref_idx_l1_active;
        poc_ref_pic_reorder(listX[LIST_1], 
                            num_ref, 
                            currSlice->reordering_of_pic_nums_idc_l1, 
                            currSlice->abs_diff_pic_num_minus1_l1, 
                            currSlice->long_term_pic_idx_l1, 0, LIST_1);
        
        //reference picture reordering
        reorder_ref_pic_list(listX[LIST_1], &listXsize[LIST_1], 
                             img->num_ref_idx_l1_active - 1, 
                             currSlice->reordering_of_pic_nums_idc_l1, 
                             currSlice->abs_diff_pic_num_minus1_l1, 
                             currSlice->long_term_pic_idx_l1);
      }
    }
  }


  //if (img->MbaffFrameFlag)
  if (img->structure==FRAME)
    init_mbaff_lists();

  if (img->type != I_SLICE && (active_pps->weighted_pred_flag == 1 || (active_pps->weighted_bipred_idc > 0 && (img->type == B_SLICE))))
  {
  	if (img->type==P_SLICE || img->type==SP_SLICE)
    {
      if (input->GenerateMultiplePPS && input->RDPictureDecision)
      {
        if (enc_picture==enc_frame_picture2)
          estimate_weighting_factor_P_slice (0);
        else
          estimate_weighting_factor_P_slice (1);
      }
      else
        estimate_weighting_factor_P_slice (0);
      
    }
    else
       estimate_weighting_factor_B_slice ();
  }

  set_ref_pic_num();

  if (img->type == B_SLICE)
    compute_colocated(Co_located, listX);
  if (img->type != I_SLICE && input->FMEnable == 3)
    EPZSSliceInit(EPZSCo_located, listX);
}


/*!
 ************************************************************************
 * \brief
 *    Allocates a slice structure along with its dependent data structures
 * \return
 *    Pointer to a Slice
 ************************************************************************
 */
static Slice *malloc_slice()
{
  int i;
  DataPartition *dataPart;
  Slice *slice;

//  const int buffer_size = (img->width * img->height * 4); // AH 190202: There can be data expansion with 
                                                          // low QP values. So, we make sure that buffer 
                                                          // does not overflow. 4 is probably safe multiplier.
  const int buffer_size = 500 + img->FrameSizeInMbs * (128 + 256 * img->bitdepth_luma + 512 * img->bitdepth_chroma);
                                                          // KS: this is approx. max. allowed code picture size

  if ((slice = (Slice *) calloc(1, sizeof(Slice))) == NULL) no_mem_exit ("malloc_slice: slice structure");

  if (input->symbol_mode == CABAC)
    {
      // create all context models
      slice->mot_ctx = create_contexts_MotionInfo();
      slice->tex_ctx = create_contexts_TextureInfo();