gst_h264_parser_parse_slice_hdr (GstH264NalParser * nalparser,
    GstH264NalUnit * nalu, GstH264SliceHdr * slice,
    gboolean parse_pred_weight_table, gboolean parse_dec_ref_pic_marking)
{
  NalReader nr;
  gint pps_id;
  GstH264PPS *pps;
  GstH264SPS *sps;
  guint start_pos;

  memset (slice, 0, sizeof (*slice));

  if (!nalu->size) {
    GST_DEBUG ("Invalid Nal Unit");
    return GST_H264_PARSER_ERROR;
  }

  nal_reader_init (&nr, nalu->data + nalu->offset + nalu->header_bytes,
      nalu->size - nalu->header_bytes);

  READ_UE (&nr, slice->first_mb_in_slice);
  READ_UE (&nr, slice->type);

  GST_DEBUG ("parsing \"Slice header\", slice type %u", slice->type);

  READ_UE_MAX (&nr, pps_id, GST_H264_MAX_PPS_COUNT - 1);
  pps = gst_h264_parser_get_pps (nalparser, pps_id);

  if (!pps) {
    GST_WARNING ("couldn't find associated picture parameter set with id: %d",
        pps_id);

    return GST_H264_PARSER_BROKEN_LINK;
  }

  slice->pps = pps;
  sps = pps->sequence;
  if (!sps) {
    GST_WARNING ("couldn't find associated sequence parameter set with id: %d",
        pps->id);
    return GST_H264_PARSER_BROKEN_LINK;
  }

  /* Check we can actually parse this slice (AVC, MVC headers only) */
  if (sps->extension_type && sps->extension_type != GST_H264_NAL_EXTENSION_MVC) {
    GST_WARNING ("failed to parse unsupported slice header");
    return GST_H264_PARSER_BROKEN_DATA;
  }

  /* set default values for fields that might not be present in the bitstream
     and have valid defaults */
  if (GST_H264_IS_I_SLICE (slice)) {
    slice->num_ref_idx_l0_active_minus1 = 0;
    slice->num_ref_idx_l1_active_minus1 = 0;
  } else {
    slice->num_ref_idx_l0_active_minus1 = pps->num_ref_idx_l0_active_minus1;

    if (GST_H264_IS_B_SLICE (slice))
      slice->num_ref_idx_l1_active_minus1 = pps->num_ref_idx_l1_active_minus1;
    else
      slice->num_ref_idx_l1_active_minus1 = 0;
  }

  if (sps->separate_colour_plane_flag)
    READ_UINT8 (&nr, slice->colour_plane_id, 2);

  READ_UINT16 (&nr, slice->frame_num, sps->log2_max_frame_num_minus4 + 4);

  if (!sps->frame_mbs_only_flag) {
    READ_UINT8 (&nr, slice->field_pic_flag, 1);
    if (slice->field_pic_flag)
      READ_UINT8 (&nr, slice->bottom_field_flag, 1);
  }

  /* calculate MaxPicNum */
  if (slice->field_pic_flag)
    slice->max_pic_num = 2 * sps->max_frame_num;
  else
    slice->max_pic_num = sps->max_frame_num;

  if (nalu->idr_pic_flag)
    READ_UE_MAX (&nr, slice->idr_pic_id, G_MAXUINT16);

  start_pos = nal_reader_get_pos (&nr);

  if (sps->pic_order_cnt_type == 0) {
    READ_UINT16 (&nr, slice->pic_order_cnt_lsb,
        sps->log2_max_pic_order_cnt_lsb_minus4 + 4);

    if (pps->pic_order_present_flag && !slice->field_pic_flag)
      READ_SE (&nr, slice->delta_pic_order_cnt_bottom);
  }

  if (sps->pic_order_cnt_type == 1 && !sps->delta_pic_order_always_zero_flag) {
    READ_SE (&nr, slice->delta_pic_order_cnt[0]);
    if (pps->pic_order_present_flag && !slice->field_pic_flag)
      READ_SE (&nr, slice->delta_pic_order_cnt[1]);
  }

  slice->pic_order_cnt_bit_size = nal_reader_get_pos (&nr) - start_pos;

  if (pps->redundant_pic_cnt_present_flag)
    READ_UE_MAX (&nr, slice->redundant_pic_cnt, G_MAXINT8);

  if (GST_H264_IS_B_SLICE (slice))
    READ_UINT8 (&nr, slice->direct_spatial_mv_pred_flag, 1);

  if (GST_H264_IS_P_SLICE (slice) || GST_H264_IS_SP_SLICE (slice) ||
      GST_H264_IS_B_SLICE (slice)) {
    READ_UINT8 (&nr, slice->num_ref_idx_active_override_flag, 1);
    if (slice->num_ref_idx_active_override_flag) {
      READ_UE_MAX (&nr, slice->num_ref_idx_l0_active_minus1, 31);

      if (GST_H264_IS_B_SLICE (slice))
        READ_UE_MAX (&nr, slice->num_ref_idx_l1_active_minus1, 31);
    }
  }

  if (!slice_parse_ref_pic_list_modification (slice, &nr,
          GST_H264_IS_MVC_NALU (nalu)))
    goto error;

  if ((pps->weighted_pred_flag && (GST_H264_IS_P_SLICE (slice)
              || GST_H264_IS_SP_SLICE (slice)))
      || (pps->weighted_bipred_idc == 1 && GST_H264_IS_B_SLICE (slice))) {
    if (!gst_h264_slice_parse_pred_weight_table (slice, &nr,
            sps->chroma_array_type))
      goto error;
  }

  if (nalu->ref_idc != 0) {
    if (!gst_h264_slice_parse_dec_ref_pic_marking (slice, nalu, &nr))
      goto error;
  }

  if (pps->entropy_coding_mode_flag && !GST_H264_IS_I_SLICE (slice) &&
      !GST_H264_IS_SI_SLICE (slice))
    READ_UE_MAX (&nr, slice->cabac_init_idc, 2);

  READ_SE_ALLOWED (&nr, slice->slice_qp_delta, -87, 77);

  if (GST_H264_IS_SP_SLICE (slice) || GST_H264_IS_SI_SLICE (slice)) {
    if (GST_H264_IS_SP_SLICE (slice))
      READ_UINT8 (&nr, slice->sp_for_switch_flag, 1);
    READ_SE_ALLOWED (&nr, slice->slice_qs_delta, -51, 51);
  }

  if (pps->deblocking_filter_control_present_flag) {
    READ_UE_MAX (&nr, slice->disable_deblocking_filter_idc, 2);
    if (slice->disable_deblocking_filter_idc != 1) {
      READ_SE_ALLOWED (&nr, slice->slice_alpha_c0_offset_div2, -6, 6);
      READ_SE_ALLOWED (&nr, slice->slice_beta_offset_div2, -6, 6);
    }
  }

  if (pps->num_slice_groups_minus1 > 0 &&
      pps->slice_group_map_type >= 3 && pps->slice_group_map_type <= 5) {
    /* Ceil(Log2(PicSizeInMapUnits / SliceGroupChangeRate + 1))  [7-33] */
    guint32 PicWidthInMbs = sps->pic_width_in_mbs_minus1 + 1;
    guint32 PicHeightInMapUnits = sps->pic_height_in_map_units_minus1 + 1;
    guint32 PicSizeInMapUnits = PicWidthInMbs * PicHeightInMapUnits;
    guint32 SliceGroupChangeRate = pps->slice_group_change_rate_minus1 + 1;
    const guint n = ceil_log2 (PicSizeInMapUnits / SliceGroupChangeRate + 1);
    READ_UINT16 (&nr, slice->slice_group_change_cycle, n);
  }

  slice->header_size = nal_reader_get_pos (&nr);
  slice->n_emulation_prevention_bytes = nal_reader_get_epb_count (&nr);

  return GST_H264_PARSER_OK;

error:
  GST_WARNING ("error parsing \"Slice header\"");
  return GST_H264_PARSER_ERROR;
}
Unknown