示例#1
0
EXPORT_C
#endif

gboolean
gst_bit_reader_skip (GstBitReader * reader, guint nbits)
{
  g_return_val_if_fail (reader != NULL, FALSE);

  if (gst_bit_reader_get_remaining (reader) < nbits)
    return FALSE;

  reader->bit += nbits;
  reader->byte += reader->bit / 8;
  reader->bit = reader->bit % 8;

  return TRUE;
}
示例#2
0
static GstFlowReturn
gst_vdp_h264_dec_parse_data (GstBaseVideoDecoder * base_video_decoder,
    GstBuffer * buf, gboolean at_eos, GstVideoFrame * frame)
{
  GstVdpH264Dec *h264_dec = GST_VDP_H264_DEC (base_video_decoder);
  GstBitReader reader;
  GstNalUnit nal_unit;
  guint8 forbidden_zero_bit;

  guint8 *data;
  guint size;
  gint i;

  GstFlowReturn ret = GST_FLOW_OK;

  GST_MEMDUMP ("data", GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf));

  gst_bit_reader_init_from_buffer (&reader, buf);

  if (gst_bit_reader_get_remaining (&reader) <
      h264_dec->nal_length_size * 8 + 7)
    goto invalid_packet;

  /* skip nal_length or sync code */
  gst_bit_reader_skip_unchecked (&reader, h264_dec->nal_length_size * 8);

  forbidden_zero_bit = gst_bit_reader_get_bits_uint8_unchecked (&reader, 1);

  if (forbidden_zero_bit != 0) {
    GST_WARNING ("forbidden_zero_bit != 0");
    return GST_FLOW_ERROR;
  }

  nal_unit.ref_idc = gst_bit_reader_get_bits_uint16_unchecked (&reader, 2);
  GST_DEBUG ("nal_ref_idc: %u", nal_unit.ref_idc);

  /* read nal_unit_type */
  nal_unit.type = gst_bit_reader_get_bits_uint16_unchecked (&reader, 5);

  GST_DEBUG ("nal_unit_type: %u", nal_unit.type);
  if (nal_unit.type == 14 || nal_unit.type == 20) {
    if (!gst_bit_reader_skip (&reader, 24))
      goto invalid_packet;
  }
  nal_unit.IdrPicFlag = (nal_unit.type == 5 ? 1 : 0);

  data = GST_BUFFER_DATA (buf) + gst_bit_reader_get_pos (&reader) / 8;
  size = gst_bit_reader_get_remaining (&reader) / 8;

  i = size - 1;
  while ((gint) size > 0 && data[i] == 0x00) {
    size--;
    i--;
  }

  if (GST_VIDEO_FRAME_FLAG_IS_SET (frame, GST_H264_FRAME_GOT_PRIMARY)) {
    if (nal_unit.type == GST_NAL_SPS || nal_unit.type == GST_NAL_PPS ||
        nal_unit.type == GST_NAL_SEI || nal_unit.type == GST_NAL_AU_DELIMITER ||
        (nal_unit.type >= 14 && nal_unit.type <= 18))
      ret =
          gst_base_video_decoder_have_frame (base_video_decoder, FALSE, &frame);
  }

  if (nal_unit.type >= GST_NAL_SLICE && nal_unit.type <= GST_NAL_SLICE_IDR) {
    GstH264Slice slice;

    if (!gst_h264_parser_parse_slice_header (h264_dec->parser, &slice, data,
            size, nal_unit))
      goto invalid_packet;

    if (slice.redundant_pic_cnt == 0) {
      if (GST_VIDEO_FRAME_FLAG_IS_SET (frame, GST_H264_FRAME_GOT_PRIMARY)) {
        GstH264Slice *p_slice;
        guint8 pic_order_cnt_type, p_pic_order_cnt_type;
        gboolean finish_frame = FALSE;

        p_slice = &(GST_H264_FRAME_CAST (frame)->slice_hdr);
        pic_order_cnt_type = slice.picture->sequence->pic_order_cnt_type;
        p_pic_order_cnt_type = p_slice->picture->sequence->pic_order_cnt_type;

        if (slice.frame_num != p_slice->frame_num)
          finish_frame = TRUE;

        else if (slice.picture != p_slice->picture)
          finish_frame = TRUE;

        else if (slice.bottom_field_flag != p_slice->bottom_field_flag)
          finish_frame = TRUE;

        else if (nal_unit.ref_idc != p_slice->nal_unit.ref_idc &&
            (nal_unit.ref_idc == 0 || p_slice->nal_unit.ref_idc == 0))
          finish_frame = TRUE;

        else if ((pic_order_cnt_type == 0 && p_pic_order_cnt_type == 0) &&
            (slice.pic_order_cnt_lsb != p_slice->pic_order_cnt_lsb ||
                slice.delta_pic_order_cnt_bottom !=
                p_slice->delta_pic_order_cnt_bottom))
          finish_frame = TRUE;

        else if ((p_pic_order_cnt_type == 1 && p_pic_order_cnt_type == 1) &&
            (slice.delta_pic_order_cnt[0] != p_slice->delta_pic_order_cnt[0] ||
                slice.delta_pic_order_cnt[1] !=
                p_slice->delta_pic_order_cnt[1]))
          finish_frame = TRUE;

        if (finish_frame)
          ret =
              gst_base_video_decoder_have_frame (base_video_decoder, FALSE,
              &frame);

      }

      if (!GST_VIDEO_FRAME_FLAG_IS_SET (frame, GST_H264_FRAME_GOT_PRIMARY)) {
        if (GST_H264_IS_I_SLICE (slice.type)
            || GST_H264_IS_SI_SLICE (slice.type))
          GST_VIDEO_FRAME_FLAG_SET (frame, GST_VIDEO_FRAME_FLAG_KEYFRAME);

        GST_H264_FRAME_CAST (frame)->slice_hdr = slice;
        GST_VIDEO_FRAME_FLAG_SET (frame, GST_H264_FRAME_GOT_PRIMARY);
      }
    }
    gst_h264_frame_add_slice ((GstH264Frame *) frame, buf);
  }

  if (nal_unit.type == GST_NAL_SPS) {
    if (!gst_h264_parser_parse_sequence (h264_dec->parser, data, size))
      goto invalid_packet;
  }

  if (nal_unit.type == GST_NAL_PPS) {
    if (!gst_h264_parser_parse_picture (h264_dec->parser, data, size))
      goto invalid_packet;
  }

  gst_buffer_unref (buf);
  return ret;

invalid_packet:
  GST_WARNING ("Invalid packet size!");
  gst_buffer_unref (buf);

  return GST_FLOW_OK;
}
static GstFlowReturn
gst_vdp_mpeg_dec_parse_data (GstBaseVideoDecoder * base_video_decoder,
    GstBuffer * buf, gboolean at_eos, GstVideoFrame * frame)
{
  GstVdpMpegDec *mpeg_dec = GST_VDP_MPEG_DEC (base_video_decoder);

  GstVdpMpegFrame *mpeg_frame;
  GstFlowReturn ret = GST_FLOW_OK;
  GstBitReader b_reader = GST_BIT_READER_INIT_FROM_BUFFER (buf);
  guint8 start_code;

  if (gst_bit_reader_get_remaining (&b_reader) < 8 * 3 + 8)
    return GST_FLOW_ERROR;

  /* skip sync_code */
  gst_bit_reader_skip_unchecked (&b_reader, 8 * 3);

  /* start_code */
  start_code = gst_bit_reader_get_bits_uint8_unchecked (&b_reader, 8);

  mpeg_frame = GST_VDP_MPEG_FRAME_CAST (frame);

  if (start_code >= MPEG_PACKET_SLICE_MIN
      && start_code <= MPEG_PACKET_SLICE_MAX) {
    GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_SLICE");

    gst_vdp_mpeg_frame_add_slice (mpeg_frame, buf);
    goto done;
  }

  switch (start_code) {
    case MPEG_PACKET_SEQUENCE:
      GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_SEQUENCE");

      if (mpeg_dec->prev_packet != -1)
        ret = gst_base_video_decoder_have_frame (base_video_decoder, FALSE,
            (GstVideoFrame **) & mpeg_frame);

      mpeg_frame->seq = buf;
      break;

    case MPEG_PACKET_PICTURE:
      GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_PICTURE");

      if (mpeg_dec->prev_packet != MPEG_PACKET_SEQUENCE &&
          mpeg_dec->prev_packet != MPEG_PACKET_GOP)
        ret = gst_base_video_decoder_have_frame (base_video_decoder, FALSE,
            (GstVideoFrame **) & mpeg_frame);

      mpeg_frame->pic = buf;
      break;

    case MPEG_PACKET_GOP:
      GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_GOP");

      if (mpeg_dec->prev_packet != MPEG_PACKET_SEQUENCE)
        ret = gst_base_video_decoder_have_frame (base_video_decoder, FALSE,
            (GstVideoFrame **) & mpeg_frame);

      mpeg_frame->gop = buf;
      break;

    case MPEG_PACKET_EXTENSION:
    {
      guint8 ext_code;

      /* ext_code */
      if (!gst_bit_reader_get_bits_uint8 (&b_reader, &ext_code, 4)) {
        ret = GST_FLOW_ERROR;
        gst_buffer_unref (buf);
        goto done;
      }

      GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_EXTENSION: %d", ext_code);

      switch (ext_code) {
        case MPEG_PACKET_EXT_SEQUENCE:
          GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_EXT_SEQUENCE");


          mpeg_frame->seq_ext = buf;

          /* so that we don't finish the frame if we get a MPEG_PACKET_PICTURE
           * or MPEG_PACKET_GOP after this */
          start_code = MPEG_PACKET_SEQUENCE;
          break;

        case MPEG_PACKET_EXT_SEQUENCE_DISPLAY:
          GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_EXT_SEQUENCE_DISPLAY");

          /* so that we don't finish the frame if we get a MPEG_PACKET_PICTURE
           * or MPEG_PACKET_GOP after this */
          start_code = MPEG_PACKET_SEQUENCE;
          break;

        case MPEG_PACKET_EXT_PICTURE_CODING:
          GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_EXT_PICTURE_CODING");

          mpeg_frame->pic_ext = buf;
          break;

        case MPEG_PACKET_EXT_QUANT_MATRIX:
          GST_DEBUG_OBJECT (mpeg_dec, "MPEG_PACKET_EXT_QUANT_MATRIX");

          mpeg_frame->qm_ext = buf;
          break;

        default:
          gst_buffer_unref (buf);
      }
      break;
    }

    default:
      gst_buffer_unref (buf);
  }

  if (at_eos && mpeg_frame->slices)
    ret = gst_base_video_decoder_have_frame (base_video_decoder, TRUE, NULL);

done:
  mpeg_dec->prev_packet = start_code;

  return ret;
}
/**
 * gst_mpeg4_parse_video_plane_with_short_header:
 * @shorthdr: The #GstMpeg4VideoPlaneShortHdr to parse
 * @data: The data to parse
 * @size: The size of the @data to parse
 */
GstMpeg4ParseResult
gst_mpeg4_parse_video_plane_short_header (GstMpeg4VideoPlaneShortHdr *
    shorthdr, const guint8 * data, gsize size)
{
  guint8 zero_bits;

  GstBitReader br = GST_BIT_READER_INIT (data, size);

  g_return_val_if_fail (shorthdr != NULL, GST_MPEG4_PARSER_ERROR);

  if (gst_bit_reader_get_remaining (&br) < 48)
    goto failed;

  if (gst_bit_reader_get_bits_uint32_unchecked (&br, 22) != 0x20)
    goto failed;

  shorthdr->temporal_reference =
      gst_bit_reader_get_bits_uint8_unchecked (&br, 8);
  CHECK_MARKER (&br);
  zero_bits = gst_bit_reader_get_bits_uint8_unchecked (&br, 1);
  if (zero_bits != 0x00)
    goto failed;

  shorthdr->split_screen_indicator =
      gst_bit_reader_get_bits_uint8_unchecked (&br, 1);
  shorthdr->document_camera_indicator =
      gst_bit_reader_get_bits_uint8_unchecked (&br, 1);
  shorthdr->full_picture_freeze_release =
      gst_bit_reader_get_bits_uint8_unchecked (&br, 1);
  shorthdr->source_format = gst_bit_reader_get_bits_uint8_unchecked (&br, 3);

  /* Set parameters/Table 6-25 */
  switch (shorthdr->source_format) {
    case 0x01:
      shorthdr->vop_width = 128;
      shorthdr->vop_height = 96;
      shorthdr->num_macroblocks_in_gob = 8;
      shorthdr->num_gobs_in_vop = 6;
      break;
    case 0x02:
      shorthdr->vop_width = 176;
      shorthdr->vop_height = 144;
      shorthdr->num_macroblocks_in_gob = 11;
      shorthdr->num_gobs_in_vop = 9;
      break;
    case 0x03:
      shorthdr->vop_width = 352;
      shorthdr->vop_height = 288;
      shorthdr->num_macroblocks_in_gob = 22;
      shorthdr->num_gobs_in_vop = 18;
      break;
    case 0x04:
      shorthdr->vop_width = 704;
      shorthdr->vop_height = 576;
      shorthdr->num_macroblocks_in_gob = 88;
      shorthdr->num_gobs_in_vop = 18;
      break;
    case 0x05:
      shorthdr->vop_width = 1408;
      shorthdr->vop_height = 1152;
      shorthdr->num_macroblocks_in_gob = 352;
      shorthdr->num_gobs_in_vop = 18;
      break;
    default:
      shorthdr->vop_width = 0;
      shorthdr->vop_height = 0;
      shorthdr->num_macroblocks_in_gob = 0;
      shorthdr->num_gobs_in_vop = 0;
  }

  shorthdr->picture_coding_type =
      gst_bit_reader_get_bits_uint8_unchecked (&br, 1);
  zero_bits = gst_bit_reader_get_bits_uint8_unchecked (&br, 4);

  if (zero_bits != 0x00)
    goto failed;

  shorthdr->vop_quant = gst_bit_reader_get_bits_uint8_unchecked (&br, 5);
  zero_bits = gst_bit_reader_get_bits_uint8_unchecked (&br, 1);

  if (zero_bits != 0x00)
    goto failed;

  do {
    READ_UINT8 (&br, shorthdr->pei, 1);

    if (shorthdr->pei == 1)
      READ_UINT8 (&br, shorthdr->psupp, 8);

  } while (shorthdr->pei == 1);

  shorthdr->size = gst_bit_reader_get_pos (&br);

  return GST_MPEG4_PARSER_OK;

failed:
  GST_WARNING ("Could not parse the Plane short header");

  return GST_MPEG4_PARSER_ERROR;
}