slice.c

This program can encode the YUV vdieo format to H.264 and decode it.

//!   CodeMB (Upper, FRAME); CodeMB (Lower, FRAME);
//! } else {
//!   CodeMB (Upper FIELD); CodeMB (Lower, FIELD);
//! }
//!
//! Open questions/issues:
//!   1. CABAC/CA-VLC state:  It seems that the CABAC/CA_VLC states are changed during the
//!      dummy encoding processes (for the R-D based selection), but that they are never
//!      reset, once the selection is made.  I believe that this breaks the MB-adaptive
//!      frame/field coding.  The necessary code for the state saves is readily available
//!      in macroblock.c, start_macroblock() and terminate_macroblock() (this code needs
//!      to be double checked that it works with CA-VLC as well
//!   2. would it be an option to allocate Bitstreams with zero data in them (or copy the
//!      already generated bitstream) for the "test coding"?

      img->write_macroblock = 0;
      if (input->MbInterlace == ADAPTIVE_CODING || input->MbInterlace == FRAME_MB_PAIR_CODING)
      {
        //================ code MB pair as frame MB ================
        //----------------------------------------------------------
        recode_macroblock = FALSE;

        img->field_mode = 0;  // MB coded as frame
        img->top_field = 0;   // Set top field to 0

        //Rate control
        img->write_macroblock = 0;
        img->bot_MB = 0;

        // save RC state only when it is going to change
        if ( input->RCEnable && input->MbInterlace == ADAPTIVE_CODING
          && img->NumberofCodedMacroBlocks > 0 && (img->NumberofCodedMacroBlocks % img->BasicUnit) == 0 )
          copy_rc_jvt( quadratic_RC_init, quadratic_RC ); // save initial RC status

        if ( input->RCEnable && input->MbInterlace == ADAPTIVE_CODING )
          copy_rc_generic( generic_RC_init, generic_RC ); // save initial RC status

        start_macroblock (CurrentMbAddr, FALSE);

        rdopt = &rddata_top_frame_mb; // store data in top frame MB
        encode_one_macroblock ();         // code the MB as frame

        FrameRDCost = rdopt->min_rdcost;
        //***   Top MB coded as frame MB ***//

        //Rate control
        img->bot_MB = 1; //for Rate control

        // go to the bottom MB in the MB pair
        img->field_mode = 0;  // MB coded as frame  //GB

        start_macroblock (CurrentMbAddr+1, FALSE);
        rdopt = &rddata_bot_frame_mb; // store data in top frame MB
        encode_one_macroblock ();         // code the MB as frame

        if ( input->RCEnable && input->MbInterlace == ADAPTIVE_CODING
          && img->NumberofCodedMacroBlocks > 0 && (img->NumberofCodedMacroBlocks % img->BasicUnit) == 0 )
          copy_rc_jvt( quadratic_RC_best, quadratic_RC ); // restore initial RC status

        if (input->RCEnable && input->MbInterlace == ADAPTIVE_CODING )
          copy_rc_generic( generic_RC_best, generic_RC ); // save frame RC stats

        FrameRDCost += rdopt->min_rdcost;

        //***   Bottom MB coded as frame MB ***//
      }

      if ((input->MbInterlace == ADAPTIVE_CODING) || (input->MbInterlace == FIELD_CODING))
      {
        //Rate control
        img->bot_MB = 0;

        //=========== start coding the MB pair as a field MB pair =============
        //---------------------------------------------------------------------
        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;

        if ( input->RCEnable && input->MbInterlace == ADAPTIVE_CODING
          && img->NumberofCodedMacroBlocks > 0 && (img->NumberofCodedMacroBlocks % img->BasicUnit) == 0 )
          copy_rc_jvt( quadratic_RC, quadratic_RC_init ); // restore initial RC status

        if ( input->RCEnable && input->MbInterlace == ADAPTIVE_CODING )
          copy_rc_generic( generic_RC, generic_RC_init ); // reset RC stats

        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 field

        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 field

        FieldRDCost += rdopt->min_rdcost;
        //***   Bottom MB coded as field MB ***//
      }

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

      //=========== decide between frame/field MB pair ============
      //-----------------------------------------------------------
      if ( ((input->MbInterlace == ADAPTIVE_CODING) && (FrameRDCost < FieldRDCost)) || input->MbInterlace == FRAME_MB_PAIR_CODING )
      {
        img->field_mode = 0;
        MBPairIsField = 0;
        if ( input->MbInterlace != FRAME_MB_PAIR_CODING )
        {
          img->buf_cycle >>= 1;
          input->num_ref_frames >>= 1;
          img->num_ref_idx_l0_active -= 1;
          img->num_ref_idx_l0_active >>= 1;
        }

        if ( input->RCEnable && input->MbInterlace == ADAPTIVE_CODING
          && img->NumberofCodedMacroBlocks > 0 && (img->NumberofCodedMacroBlocks % img->BasicUnit) == 0 )
          copy_rc_jvt( quadratic_RC, quadratic_RC_best ); // restore initial RC status

        if ( input->RCEnable && input->MbInterlace == ADAPTIVE_CODING )
          copy_rc_generic( generic_RC, generic_RC_best ); // restore frame RC stats

        //Rate control
        img->write_mbaff_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);
          img->NumberofCodedMacroBlocks -= 2;
          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);
        img->NumberofCodedMacroBlocks--;
        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 ( !end_of_slice )
      {
        assert( CurrentMbAddr < (int)img->PicSizeInMbs );
        assert( CurrentMbAddr >= 0 );
        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,j;
  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]);

    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;

  // primary and redundant slices: number of references overriding.
  if(input->redundant_pic_flag)
  {
    if(!redundant_coding)
    {
      img->num_ref_idx_l0_active = imin(img->number,input->NumRefPrimary);
    }
    else
    {
      // 1 reference picture for redundant slices
      img->num_ref_idx_l0_active = 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 = imin(img->num_ref_idx_l0_active, input->P_List0_refs * ((img->structure !=0) + 1));
  }
  if (img->type == B_SLICE )
  {
    if (input->B_List0_refs)
    {
      img->num_ref_idx_l0_active = imin(img->num_ref_idx_l0_active, input->B_List0_refs * ((img->structure !=0) + 1));
    }
    if (input->B_List1_refs)
    {
      img->num_ref_idx_l1_active = imin(img->num_ref_idx_l1_active, input->B_List1_refs * ((img->structure !=0) + 1));
    }
  }
  // generate reference picture lists
  init_lists(img->type, (PictureStructure) 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];

  //Perform memory management based on poc distances
  //if (img->nal_reference_idc  && input->HierarchicalCoding && input->PocMemoryManagement && dpb.ref_frames_in_buffer==active_sps->num_ref_frames)
  if (img->nal_reference_idc  && 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++)