slice.c

Nokia H.264/AVC Encoder/Decoder Usage Manual

/*
COPYRIGHT, LICENSE AND WARRANTY INFORMATION

This software module has been originally developed by Nokia Corporation. 

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(hereinafter Licensee) comply with all the terms and conditions of this 
Statement and subject to the limitations set forth in this Statement Nokia 
grants to such Licensee a non-exclusive, sub-licensable, worldwide, 
limited license under copyrights owned by Nokia to use the Software for 
the sole purpose of creating, manufacturing, selling, marketing, or  
distributing (including the right to make modifications to the Software) 
a fully compliant decoder implementation (hereinafter "Decoder") of 
ITU-T Recommendation H.264 / ISO/IEC International Standard 14496-10 and 
an encoder implementation producing output that is decodable with the 
Decoder.

Nokia retains the ownership of copyrights to the Software. There is no 
patent nor other intellectual property right of Nokia licensed under this 
Statement (except the copyright license above). Licensee hereby assumes 
sole responsibility to secure any other intellectual property rights 
needed, if any. For example, if patent licenses  are required, it is 
their responsibility to acquire the license before utilizing the Software.

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non-exclusive, worldwide, royalty-free, perpetual and irrevocable 
covenant that the Licensee(s) shall not bring a suit before any court or 
administrative agency or otherwise assert a claim for infringement under 
the Licensee intellectual property rights that, but for a license, would 
be infringed by the Software against  
   (a)  Nokia or Nokia's Affiliate; or  
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        to the Software from Nokia; or 
   (c)  contractor, customer or distributor of a party listed above in a 
        or b,  
which suit or claim is related to the Software or use thereof.

The Licensee(s) further agrees to grant a reciprocal license to Nokia 
(as granted by Nokia to the Licensee(s) on the modifications made by 
Licensee(s) to the Software. 

THE SOFTWARE IS PROVIDED "AS IS" AND THE ORIGINAL DEVELOPER DISCLAIMS 
ANY AND ALL WARRANTIES WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING 
BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS 
FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. THOSE INTENDING TO USE 
THE SOFTWARE ARE EXPRESSLY ADVISED THAT ITS USE MAY INFRINGE EXISTING 
PATENTS AND BE SUBJECT TO ROYALTY PAYMENTS TO PATENT OWNERS. ANYONE 
USING THE SOFTWARE ON THE BASIS OF THIS LICENSE AGREES TO OBTAIN THE 
NECESSARY PERMISSIONS FROM ANY AND ALL APPLICABLE PATENT OWNERS FOR SUCH 
USE.

IN NO EVENT SHALL THE ORIGINAL DEVELOPER BE LIABLE FOR ANY CLAIM, 
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT 
OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE 
OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

This copyright, license and warranty information notice must be retained 
in all copies and derivative works of the Software or substantial 
portions thereof.
*/




#include <math.h>
#include <string.h>

#include "nccglob.h"
#include "globals.h"
#include "debug.h"
#include "bitbuffer.h"
#include "vlcutility.h"
#include "macroblock.h"
#include "slice.h"
#include "refframe.h"
#include <limits.h>
#include "stream.h"
#include "ratecontrol.h"



static int sliceSendRefListReordering(dpbBuf_s    *dpbBuf, 
                                      bitbuffer_s *bitbuf)
{
  int i, bits, numCmds;
  int refPicListReorderingFlagL0;

  // let's check whether it is necessary to send re-order command
  numCmds = dpbGetReorderCommands(dpbBuf);

  /* encode the reordering commands */
  refPicListReorderingFlagL0 = (numCmds != 0);

  bits = u_n(bitbuf, refPicListReorderingFlagL0, 1);

  if (refPicListReorderingFlagL0) {
    /* TODO */
    for (i = 0; i < numCmds; i++) {
      bits += ue_v(bitbuf, dpbBuf->reorderCmds[i].idc);

      if (dpbBuf->reorderCmds[i].idc == 0 || dpbBuf->reorderCmds[i].idc == 1)
        bits += ue_v(bitbuf, dpbBuf->reorderCmds[i].absDiffPicNumMinus1);
      else if (dpbBuf->reorderCmds[i].idc == 2)
        bits += ue_v(bitbuf, dpbBuf->reorderCmds[i].longTermPicNum);
    }

    // end of the re-order command list
    bits += ue_v(bitbuf, 3);
  }

  return bits;
}


static int encRefPicMarking(slice_s     *slice, 
                            MMCO_s      *mmcoList, 
                            int         idrLongTermRefFlag,
                            bitbuffer_s *bitbuf)
{
  int bits = 0;
  int noOutputOfPriorPicsFlag, adaptiveRefMarkingModeFlag;

  noOutputOfPriorPicsFlag = 0;

  /* Decoded reference picture marking process will be delayed after all the slices are decoded */
  if (slice->isIDR) {
    bits += u_n(bitbuf, noOutputOfPriorPicsFlag, 1);
    bits += u_n(bitbuf, idrLongTermRefFlag, 1);
  }
  else { /* non-IDR */
    adaptiveRefMarkingModeFlag = 0;
    if (mmcoList->mmco != 0)
      adaptiveRefMarkingModeFlag = 1;

    bits += u_n(bitbuf, adaptiveRefMarkingModeFlag, 1);

    if (adaptiveRefMarkingModeFlag) {
      do {
        bits += ue_v(bitbuf, mmcoList->mmco);
        if (mmcoList->mmco == 1 || mmcoList->mmco == 3)
          bits += ue_v(bitbuf, mmcoList->diffPicNumMinus1);
        if (mmcoList->mmco == 2)
          bits += ue_v(bitbuf, mmcoList->longTermPicNum);
        if (mmcoList->mmco == 3 || mmcoList->mmco == 6)
          bits += ue_v(bitbuf, mmcoList->longTermFrmIdx);
        if (mmcoList->mmco == 4)
          bits += ue_v(bitbuf, mmcoList->maxLongTermFrmIdxPlus1);

        if (mmcoList->mmco != 0) {
          mmcoList = mmcoList->next;
        }
        else
          mmcoList = 0;
      } while (mmcoList != 0);
    }
  }

  return bits;
}


/*
 * startSlice
 *
 * Parameters:
 *      slice                 Slice coding structure
 *      sps                   Sequence parameter set
 *      pps                   Picture parameter set
 *      bitsNal               Pointer to counter accumulating NAL bits
 *
 * Function:
 *      Send slice header information.
 *
 * Returns:
 *      Length of the slice header in bits.
 *
 */
static int startSlice(slice_s             *slice, 
                      encParams_s         *encPar,
                      int                 firstMbAddr,
                      dpbBuf_s            *dpbBuf,
                      seq_parameter_set_s *sps, 
                      pic_parameter_set_s *pps,
                      int                 *bitsNal)
{
  int i, bits;
  int deltaQp, value;
  int expectedPicOrderCnt;
  int picOrderCntCycleCnt;
  int expectedDeltaPerPicOrderCntCycle;
  int frameNumInPicOrderCntCycle;
  int absFrameNum;

  int temp;
  int len1;
  bitbuffer_s *bitbuf;

  bitbuf = slice->bitbuf;
  bits = 0;
  picOrderCntCycleCnt = 0;
  frameNumInPicOrderCntCycle = 0;

  /* Do not take the bits prior to the starting code into account */
  /* Nor the naltype byte */
  /* 1 zero byte is always present */
  *bitsNal += vlcuSendNalUnitStartCodePrefix(slice->bitbuf, 1);
  if (slice->isIDR == 1) 
    *bitsNal += vlcuSendNalHead(slice->bitbuf, slice->nalRefIdc, CODED_SLICE_IDR_NAL_TYPE);
  else 
    *bitsNal += vlcuSendNalHead(slice->bitbuf, slice->nalRefIdc, CODED_SLICE_NAL_TYPE);

  /* first_mb_in_slice */
  bits += ue_v(bitbuf, firstMbAddr);

  /* slice_type */
  bits += ue_v(bitbuf, slice->sliceType);

  /* pps id */
  bits += ue_v(bitbuf, 0);

  /* frame_num */
  bits += u_n(bitbuf, dpbBuf->frameNum, encPar->log2_max_frame_num_minus4+4);
  
  /* idr pic id */
  if (slice->isIDR) {
    bits += ue_v(bitbuf, slice->idrPicId);
  }

  /* POC: Picture order count */
  if (sps->pic_order_cnt_type == 0) {
    unsigned int mask;

    /* pic_order_cnt_lsb */
    mask = (1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4)) - 1;
    value = (slice->poc & mask);
    bits += u_n(bitbuf, value, sps->log2_max_pic_order_cnt_lsb_minus4+4);
  }
  else if (sps->pic_order_cnt_type == 1 && !sps->delta_pic_order_always_zero_flag) {

    /* Reset prevFrameNumOffset if needed */
    if (slice->isIDR || dpbBuf->prevPicHasMMCO5) { /* Todo: prevPicHasMMCO5 has not been tested. */
      dpbBuf->prevFrameNumOffset = 0;
    }

    /* frameNumOffset is derived as follows: */
    if (slice->isIDR)
      dpbBuf->frameNumOffset = 0;
    else if (dpbBuf->prevRefFrameNum > dpbBuf->frameNum)
      dpbBuf->frameNumOffset = dpbBuf->prevFrameNumOffset + dpbBuf->maxFrameNum;
    else
      dpbBuf->frameNumOffset = dpbBuf->prevFrameNumOffset;

    /* absFrameNum is derived as follows: */
    if (sps->num_ref_frames_in_pic_order_cnt_cycle != 0)
      absFrameNum = dpbBuf->frameNumOffset + dpbBuf->frameNum;
    else
      absFrameNum = 0;
    if (slice->nalRefIdc == 0 && absFrameNum > 0)
      absFrameNum = absFrameNum - 1;

    /* When absFrameNum > 0, picOrderCntCycleCnt and frameNumInPicOrderCntCycle are derived as follows */
    if (absFrameNum > 0) {
      picOrderCntCycleCnt = (absFrameNum - 1) / sps->num_ref_frames_in_pic_order_cnt_cycle;
      frameNumInPicOrderCntCycle = (absFrameNum - 1) % sps->num_ref_frames_in_pic_order_cnt_cycle;
    }

    /* expectedDeltaPerPicOrderCntCycle */
    expectedDeltaPerPicOrderCntCycle = 0;
    for (i = 0; i < (int)sps->num_ref_frames_in_pic_order_cnt_cycle; i++)
      expectedDeltaPerPicOrderCntCycle += sps->offset_for_ref_frame[i];

    /* expectedPicOrderCnt */
    if (absFrameNum > 0) {
      expectedPicOrderCnt = picOrderCntCycleCnt * expectedDeltaPerPicOrderCntCycle;
      for (i = 0; i <= frameNumInPicOrderCntCycle; i++)
        expectedPicOrderCnt = expectedPicOrderCnt + sps->offset_for_ref_frame[i];
    } else
      expectedPicOrderCnt = 0;
    if (slice->nalRefIdc == 0)
      expectedPicOrderCnt = expectedPicOrderCnt + sps->offset_for_non_ref_pic;

    /* delta_pic_order_cnt[ 0 ] */
    value = slice->poc - expectedPicOrderCnt;
    bits += se_v(bitbuf, value);
  }

  /* reference picture management */
  if (IS_SLICE_P(slice->sliceType)) {
    int numRefIdxActiveOverrideFlag;

    // these should be dynamically determined
    numRefIdxActiveOverrideFlag = 
      ((int) (pps->num_ref_idx_l0_active_minus1 + 1) > dpbBuf->numRefFrms) ? 1 : 0;

    bits += u_n(bitbuf, numRefIdxActiveOverrideFlag, 1);

    if (numRefIdxActiveOverrideFlag)
      bits += ue_v(bitbuf, dpbBuf->numRefFrms - 1);
  }

  /* send reference frame reordering syntax elements */
  if (! IS_SLICE_I(slice->sliceType)) 
    bits += sliceSendRefListReordering(dpbBuf, bitbuf);

  /* ref pic marking, including writing MMCO commands if any. */
  if (slice->nalRefIdc) {
    bits += encRefPicMarking(slice, dpbBuf->mmcoList, dpbBuf->ltrIdr, bitbuf);
  }

  /* slice_qp_delta */
  deltaQp = slice->qp - pps->pic_init_qp_minus26 - 26;
  bits += se_v(bitbuf, deltaQp);

  /* deblocking filter */
  if (pps->deblocking_filter_parameters_present_flag == 1) {
    bits += ue_v(bitbuf, encPar->filterMode); // ue_v(bitbuf, &slice->disableDeblockingFilterIdc);
    if (encPar->filterMode != 1) {
      bits += se_v(bitbuf, encPar->alphaOffset/2);
      bits += se_v(bitbuf, encPar->betaOffset/2);
    }
  }

  /* macroblock to slice group map */
  if ((pps->num_slice_groups_minus1 > 0) && (pps->slice_group_map_type >= 3)
    && (pps->slice_group_map_type <= 5))
  {
    int picSizeInMapUnits;

    picSizeInMapUnits = slice->mbksPerCol * slice->mbksPerLine;

    // find minimal # of bits to store maximal possible sliceGroupChangeCycle
    // slightly different from the original implementation
    temp = picSizeInMapUnits/(pps->slice_group_change_rate_minus1 + 1);
    len1 = 0;
    do
    {
      len1 ++;
      temp >>= 1;
    } while (temp);

    /* read slice_group_change_cycle */
    bits += u_n(bitbuf, slice->sliceGroupChangeCycle, len1);
  }

  return bits;
}


/*
 * sliceGenerateMbMap
 *
 * Parameters:
 *      slice                 Slice coding structure
 *      pps                   Picture parameter set
 *
 * Function:
 *      Generate the slice group maps from the parameters stored in picture
 *      parameter set.
 *
 * Returns:
 *      -
 *
 */
void sliceGenerateMbMap(slice_s             *slice, 
                        pic_parameter_set_s *pps)
{
  int i, j, k;
  int x, y;
  int iGroup;
  int picSizeInMapUnits, picWidthInMbs, picHeightInMapUnits;
  int mapUnitsInSliceGroup0;
  int sizeOfUpperLeftGroup;
  mbState_s *pMbStateArr;

  pMbStateArr = slice->mbStateArr;
  for (i = 0; i < slice->picSizeInMbs; i ++) {
    // mbType is used to indicate whether an MB has been encoded
    pMbStateArr[i].mbType   = -1;
    pMbStateArr[i].sliceMap = 0;
  }

  /* macroblock to slice group map */
  if (pps->num_slice_groups_minus1 > 0) {
    picSizeInMapUnits   = slice->mbksPerCol * slice->mbksPerLine;
    picWidthInMbs       = slice->mbksPerLine;
    picHeightInMapUnits = slice->mbksPerCol;

    // mapUnitsInSliceGroup0 only used in slice_group_map_type 3, 4, 5