int dabWrite_EncodeHeader(HANDLE_DAB hDab,
                                 HANDLE_FDK_BITSTREAM hBitStream,
                                 int buffer_fullness,
                                 int frame_length)
{
  INT crcIndex = 0;


  FDK_ASSERT(((frame_length+hDab->headerBits)/8)<0x2000);      /*13 bit*/
  FDK_ASSERT(buffer_fullness<0x800);    /* 11 bit   */

  FDKcrcReset(&hDab->crcInfo);


//  fprintf(stderr, "dabWrite_EncodeHeader() hDab->currentBlock=%d, frame_length=%d, buffer_fullness=%d\n",
//		  hDab->currentBlock, frame_length, buffer_fullness);

//  if (hDab->currentBlock == 0) {
//	//hDab->subFrameStartPrev=dabWrite_GetHeaderBits(hDab);
//	fprintf(stderr, "header bits[%d] [%d]\n", hDab->subFrameStartPrev, hDab->subFrameStartPrev >> 3);
//    FDKresetBitbuffer(hBitStream, BS_WRITER);
//  }

  //hDab->subFrameStartBit = FDKgetValidBits(hBitStream);
//  fprintf(stderr, "dabWrite_EncodeHeader() hDab->subFrameStartBit=%d [%d]\n", hDab->subFrameStartBit, hDab->subFrameStartBit >> 3);

  //hDab->subFrameStartBit = FDKgetValidBits(hBitStream);
  /* Skip new header if this is raw data block 1..n */
  if (hDab->currentBlock == 0)
  {
    FDKresetBitbuffer(hBitStream, BS_WRITER);
//    fprintf(stderr, "dabWrite_EncodeHeader() after FDKresetBitbuffer=%d [%d]\n", FDKgetValidBits(hBitStream), FDKgetValidBits(hBitStream) >> 3);

    /* fixed header */
    FDKwriteBits(hBitStream, 0, 16); //header_firecode
    FDKwriteBits(hBitStream, 0, 1); //rfa
    FDKwriteBits(hBitStream, hDab->dac_rate, 1);
    FDKwriteBits(hBitStream, hDab->sbr_flag, 1);
    FDKwriteBits(hBitStream, hDab->aac_channel_mode, 1);
    FDKwriteBits(hBitStream, hDab->ps_flag, 1);
    FDKwriteBits(hBitStream, hDab->mpeg_surround_config, 3);
    /* variable header */
    int i;
    for(i=0; i<hDab->num_raw_blocks; i++)
    	FDKwriteBits(hBitStream, 0, 12);
    /* padding */
    if (hDab->dac_rate == 0 || hDab->sbr_flag == 0) {
    	FDKwriteBits(hBitStream, 0, 4);
    }
  } /* End of DAB header */

  hDab->subFrameStartBit = FDKgetValidBits(hBitStream);
  FDK_ASSERT(FDKgetValidBits(hBitStream) % 8 == 0); //only aligned header

//  fprintf(stderr, "dabWrite_EncodeHeader() FDKgetValidBits(hBitStream)=%d [%d]\n", FDKgetValidBits(hBitStream), FDKgetValidBits(hBitStream) >> 3);
  return 0;
}
示例#2
0
static
TRANSPORTDEC_ERROR synchronization(
        HANDLE_TRANSPORTDEC hTp,
        INT                *pHeaderBits
        )
{
  TRANSPORTDEC_ERROR err = TRANSPORTDEC_OK, errFirstFrame = TRANSPORTDEC_OK;
  HANDLE_FDK_BITSTREAM hBs = &hTp->bitStream[0];

  INT syncLayerFrameBits = 0; /* Length of sync layer frame (i.e. LOAS) */
  INT rawDataBlockLength = 0, rawDataBlockLengthPrevious;
  INT totalBits;
  INT headerBits = 0, headerBitsFirstFrame = 0, headerBitsPrevious;
  INT numFramesTraversed = 0, fTraverseMoreFrames, fConfigFound = 0, startPos, startPosFirstFrame = -1;
  INT numRawDataBlocksFirstFrame = 0, numRawDataBlocksPrevious, globalFramePosFirstFrame = 0, rawDataBlockLengthFirstFrame = 0;
  INT ignoreBufferFullness = hTp->flags & (TPDEC_IGNORE_BUFFERFULLNESS|TPDEC_SYNCOK);

  /* Synch parameters */
  INT syncLength;      /* Length of sync word in bits */
  UINT syncWord;       /* Sync word to be found */
  UINT syncMask;       /* Mask for sync word (for adding one bit, so comprising one bit less) */
  C_ALLOC_SCRATCH_START(contextFirstFrame, transportdec_parser_t, 1);

  totalBits = (INT)FDKgetValidBits(hBs);

  if (totalBits <= 0) {
    /* Return sync error, because this happens only in case of severly damaged bit streams.
       Returning TRANSPORTDEC_NOT_ENOUGH_BITS here is very dangerous. */
    /* numberOfRawDataBlocks must be always reset in case of sync errors. */
    hTp->numberOfRawDataBlocks = 0;
    goto bail;
  }

  fTraverseMoreFrames = (hTp->flags & (TPDEC_MINIMIZE_DELAY|TPDEC_EARLY_CONFIG)) && ! (hTp->flags & TPDEC_SYNCOK);

  /* Set transport specific sync parameters */
  switch (hTp->transportFmt) {
    case TT_MP4_ADTS:
      syncWord = ADTS_SYNCWORD;
      syncLength = ADTS_SYNCLENGTH;
      break;
    case TT_MP4_LOAS:
      syncWord = 0x2B7;
      syncLength = 11;
      break;
    default:
      syncWord = 0;
      syncLength = 0;
      break;
  }

  syncMask = (1<<syncLength)-1;

  do {
    INT bitsAvail = 0;     /* Bits available in bitstream buffer    */
    INT checkLengthBits;   /* Helper to check remaining bits and buffer boundaries */
    UINT synch;            /* Current sync word read from bitstream */

    headerBitsPrevious = headerBits;

    bitsAvail = (INT)FDKgetValidBits(hBs);

    if (hTp->numberOfRawDataBlocks == 0) {
      /* search synchword */

      FDK_ASSERT( (bitsAvail % TPDEC_SYNCSKIP) == 0);

      if ((bitsAvail-syncLength) < TPDEC_SYNCSKIP) {
        err = TRANSPORTDEC_NOT_ENOUGH_BITS;
        headerBits = 0;
      } else {

        synch = FDKreadBits(hBs, syncLength);

        if ( !(hTp->flags & TPDEC_SYNCOK) ) {
          for (; (bitsAvail-syncLength) >= TPDEC_SYNCSKIP; bitsAvail-=TPDEC_SYNCSKIP) {
            if (synch == syncWord) {
              break;
            }
            synch = ((synch << TPDEC_SYNCSKIP) & syncMask) | FDKreadBits(hBs, TPDEC_SYNCSKIP);
          }
        }
        if (synch != syncWord) {
          /* No correct syncword found. */
          err = TRANSPORTDEC_SYNC_ERROR;
        } else {
          err = TRANSPORTDEC_OK;
        }
        headerBits = syncLength;
      }
    } else {
      headerBits = 0;
    }

    /* Save previous raw data block data */
    rawDataBlockLengthPrevious = rawDataBlockLength;
    numRawDataBlocksPrevious = hTp->numberOfRawDataBlocks;

    /* Parse transport header (raw data block granularity) */
    startPos = FDKgetValidBits(hBs);

    if (err == TRANSPORTDEC_OK )
    {
      switch (hTp->transportFmt) {
        case TT_MP4_ADTS:
          if (hTp->numberOfRawDataBlocks <= 0)
          {
            int errC;

            /* Parse ADTS header */
            err = adtsRead_DecodeHeader( &hTp->parser.adts, &hTp->asc[0], hBs, ignoreBufferFullness );
            if (err != TRANSPORTDEC_OK) {
              if (err != TRANSPORTDEC_NOT_ENOUGH_BITS) {
                err = TRANSPORTDEC_SYNC_ERROR;
              }
            } else {
              errC = hTp->callbacks.cbUpdateConfig(hTp->callbacks.cbUpdateConfigData, &hTp->asc[0]);
              if (errC != 0) {
                err = TRANSPORTDEC_SYNC_ERROR;
              } else {
                hTp->numberOfRawDataBlocks = hTp->parser.adts.bs.num_raw_blocks+1;
                /* CAUTION: The PCE (if available) is declared to be a part of the header! */
                hTp->globalFramePos = FDKgetValidBits(hBs) + hTp->parser.adts.bs.num_pce_bits;
              }
            }
          }
          else {
            /* Reset CRC because the next bits are the beginning of a raw_data_block() */
            FDKcrcReset(&hTp->parser.adts.crcInfo);
            hTp->globalFramePos = FDKgetValidBits(hBs);
          }
          if (err == TRANSPORTDEC_OK) {
            hTp->numberOfRawDataBlocks--;
            rawDataBlockLength = adtsRead_GetRawDataBlockLength(&hTp->parser.adts, (hTp->parser.adts.bs.num_raw_blocks-hTp->numberOfRawDataBlocks));
            syncLayerFrameBits = (hTp->parser.adts.bs.frame_length<<3) - (startPos - FDKgetValidBits(hBs)) - syncLength;
            if (syncLayerFrameBits <= 0) {
              err = TRANSPORTDEC_SYNC_ERROR;
            }
          } else {
            hTp->numberOfRawDataBlocks = 0;
          }
          break;
        case TT_MP4_LOAS:
          if (hTp->numberOfRawDataBlocks <= 0)
          {
            syncLayerFrameBits = FDKreadBits(hBs, 13);
            hTp->parser.latm.m_audioMuxLengthBytes = syncLayerFrameBits;
            syncLayerFrameBits <<= 3;
          }
        case TT_MP4_LATM_MCP1:
        case TT_MP4_LATM_MCP0:
          if (hTp->numberOfRawDataBlocks <= 0)
          {
            hTp->globalFramePos = FDKgetValidBits(hBs);

            err = CLatmDemux_Read(
                    hBs,
                   &hTp->parser.latm,
                    hTp->transportFmt,
                   &hTp->callbacks,
                    hTp->asc,
                    ignoreBufferFullness);

            if (err != TRANSPORTDEC_OK) {
              if (err != TRANSPORTDEC_NOT_ENOUGH_BITS) {
                err = TRANSPORTDEC_SYNC_ERROR;
              }
            } else {
              hTp->numberOfRawDataBlocks = CLatmDemux_GetNrOfSubFrames(&hTp->parser.latm);
              syncLayerFrameBits -= startPos - FDKgetValidBits(hBs) - (13);            
            }
          } else {
            err = CLatmDemux_ReadPayloadLengthInfo(hBs, &hTp->parser.latm);
            if (err != TRANSPORTDEC_OK) {
              err = TRANSPORTDEC_SYNC_ERROR;
            }
          }
          if (err == TRANSPORTDEC_OK) {
            rawDataBlockLength = CLatmDemux_GetFrameLengthInBits(&hTp->parser.latm);
            hTp->numberOfRawDataBlocks--;
          } else {
            hTp->numberOfRawDataBlocks = 0;
          }
          break;
        default:
          {
            syncLayerFrameBits = 0;
          }
          break;
      }
    }

    headerBits += startPos - (INT)FDKgetValidBits(hBs);
    bitsAvail -= headerBits;

    checkLengthBits  = syncLayerFrameBits;

    /* Check if the whole frame would fit the bitstream buffer */
    if (err == TRANSPORTDEC_OK) {
      if ( (checkLengthBits+headerBits) > ((TRANSPORTDEC_INBUF_SIZE<<3)-7) ) {
        /* We assume that the size of the transport bit buffer has been
           chosen to meet all system requirements, thus this condition
           is considered a synchronisation error. */
        err = TRANSPORTDEC_SYNC_ERROR;
      } else {
        if ( bitsAvail < checkLengthBits ) {
          err = TRANSPORTDEC_NOT_ENOUGH_BITS;
        }
      }
    }

    if (err == TRANSPORTDEC_NOT_ENOUGH_BITS) {
      break;
    }


    if (err == TRANSPORTDEC_SYNC_ERROR) {
      int bits;

      /* Enforce re-sync of transport headers. */
      hTp->numberOfRawDataBlocks = 0;

      /* Ensure that the bit amount lands and a multiple of TPDEC_SYNCSKIP */
      bits = (bitsAvail + headerBits) % TPDEC_SYNCSKIP;
      /* Rewind - TPDEC_SYNCSKIP, in order to look for a synch one bit ahead next time. */
      FDKpushBiDirectional(hBs, -(headerBits - TPDEC_SYNCSKIP) + bits);
      bitsAvail += headerBits - TPDEC_SYNCSKIP - bits;
      headerBits = 0;      
    }

    /* Frame traversal */
    if ( fTraverseMoreFrames )
    {
      /* Save parser context for early config discovery "rewind all frames" */
      if ( (hTp->flags & TPDEC_EARLY_CONFIG) && !(hTp->flags & TPDEC_MINIMIZE_DELAY))
      {
        /* ignore buffer fullness if just traversing additional frames for ECD */
        ignoreBufferFullness = 1;

        /* Save context in order to return later */
        if ( err == TRANSPORTDEC_OK && startPosFirstFrame == -1 ) {
          startPosFirstFrame = FDKgetValidBits(hBs);
          numRawDataBlocksFirstFrame = hTp->numberOfRawDataBlocks;
          globalFramePosFirstFrame = hTp->globalFramePos;
          rawDataBlockLengthFirstFrame = rawDataBlockLength;
          headerBitsFirstFrame = headerBits;
          errFirstFrame = err;
          FDKmemcpy(contextFirstFrame, &hTp->parser, sizeof(transportdec_parser_t));
        }

        /* Break when config was found or it is not possible anymore to find a config */
        if (startPosFirstFrame != -1 && (fConfigFound || err != TRANSPORTDEC_OK)) {
          break;
        }
      }

      if (err == TRANSPORTDEC_OK) {
        FDKpushFor(hBs, rawDataBlockLength);
        bitsAvail -= rawDataBlockLength;
        numFramesTraversed++;
        /* Ignore error here itentionally. */
        transportDec_AdjustEndOfAccessUnit(hTp);
      }
    }
  } while ( fTraverseMoreFrames || (err == TRANSPORTDEC_SYNC_ERROR && !(hTp->flags & TPDEC_SYNCOK)));

  /* Restore context in case of ECD frame traversal */
  if ( startPosFirstFrame != -1 && (fConfigFound || err != TRANSPORTDEC_OK) ) {
    FDKpushBiDirectional(hBs, FDKgetValidBits(hBs) - startPosFirstFrame);
    FDKmemcpy(&hTp->parser, contextFirstFrame, sizeof(transportdec_parser_t));
    hTp->numberOfRawDataBlocks = numRawDataBlocksFirstFrame;
    hTp->globalFramePos = globalFramePosFirstFrame;
    rawDataBlockLength = rawDataBlockLengthFirstFrame;
    headerBits = headerBitsFirstFrame;
    err = errFirstFrame;
    numFramesTraversed = 0;
  } 

  /* Additional burst data mode buffer fullness check. */
  if ( !(hTp->flags & (TPDEC_IGNORE_BUFFERFULLNESS|TPDEC_SYNCOK)) && err == TRANSPORTDEC_OK) {
    err = additionalHoldOffNeeded(hTp, transportDec_GetBufferFullness(hTp), FDKgetValidBits(hBs) - syncLayerFrameBits);
    if (err == TRANSPORTDEC_NOT_ENOUGH_BITS) {
      hTp->holdOffFrames++;
    }
  }
  
  /* Rewind for retry because of not enough bits */
  if (err == TRANSPORTDEC_NOT_ENOUGH_BITS) {
    FDKpushBack(hBs, headerBits);
    headerBits = 0;
  }
  else {
    /* reset hold off frame counter */
    hTp->holdOffFrames = 0;
  }

  /* Return to last good frame in case of frame traversal but not ECD. */
  if (numFramesTraversed > 0) {
    FDKpushBack(hBs, rawDataBlockLengthPrevious);
    if (err != TRANSPORTDEC_OK) {
      hTp->numberOfRawDataBlocks = numRawDataBlocksPrevious;
      headerBits = headerBitsPrevious;
    }
    err = TRANSPORTDEC_OK;
  }

bail:
  hTp->auLength[0] = rawDataBlockLength;

  if (err == TRANSPORTDEC_OK) {
    hTp->flags |= TPDEC_SYNCOK;
  }

  if (pHeaderBits != NULL) {
    *pHeaderBits = headerBits;
  }

  if (err == TRANSPORTDEC_SYNC_ERROR) {
    hTp->flags &= ~TPDEC_SYNCOK;
  }

  C_ALLOC_SCRATCH_END(contextFirstFrame, transportdec_parser_t, 1);

  return err;
}
示例#3
0
int adtsWrite_EncodeHeader(HANDLE_ADTS hAdts,
                                 HANDLE_FDK_BITSTREAM hBitStream,
                                 int buffer_fullness,
                                 int frame_length)
{
  INT crcIndex = 0;


  hAdts->headerBits = adtsWrite_GetHeaderBits(hAdts);

  FDK_ASSERT(((frame_length+hAdts->headerBits)/8)<0x2000);      /*13 bit*/
  FDK_ASSERT(buffer_fullness<0x800);    /* 11 bit   */

  if (!hAdts->protection_absent) {
    FDKcrcReset(&hAdts->crcInfo);
  }

  if (hAdts->currentBlock == 0) {
    FDKresetBitbuffer(hBitStream, BS_WRITER);
  }

  hAdts->subFrameStartBit = FDKgetValidBits(hBitStream);

  /* Skip new header if this is raw data block 1..n */
  if (hAdts->currentBlock == 0)
  {
    FDKresetBitbuffer(hBitStream, BS_WRITER);

    if (hAdts->num_raw_blocks == 0) {
      crcIndex = adtsWrite_CrcStartReg(hAdts, hBitStream, 0);
    }

    /* fixed header */
    FDKwriteBits(hBitStream, 0xFFF, 12);
    FDKwriteBits(hBitStream, hAdts->mpeg_id, 1);
    FDKwriteBits(hBitStream, hAdts->layer, 2);
    FDKwriteBits(hBitStream, hAdts->protection_absent, 1);
    FDKwriteBits(hBitStream, hAdts->profile, 2);
    FDKwriteBits(hBitStream, hAdts->sample_freq_index, 4);
    FDKwriteBits(hBitStream, hAdts->private_bit, 1);
    FDKwriteBits(hBitStream, getChannelConfig(hAdts->channel_mode), 3);
    FDKwriteBits(hBitStream, hAdts->original, 1);
    FDKwriteBits(hBitStream, hAdts->home, 1);
    /* variable header */
    FDKwriteBits(hBitStream, hAdts->copyright_id, 1);
    FDKwriteBits(hBitStream, hAdts->copyright_start, 1);
    FDKwriteBits(hBitStream, (frame_length + hAdts->headerBits)>>3, 13);
    FDKwriteBits(hBitStream, buffer_fullness, 11);
    FDKwriteBits(hBitStream, hAdts->num_raw_blocks, 2);

    if (!hAdts->protection_absent) {
      int i;

      /* End header CRC portion for single raw data block and write dummy zero values for unknown fields. */
      if (hAdts->num_raw_blocks == 0) {
        adtsWrite_CrcEndReg(hAdts, hBitStream, crcIndex);
      } else {
        for (i=0; i<hAdts->num_raw_blocks; i++) {
          FDKwriteBits(hBitStream, 0, 16);
        }
      }
      FDKwriteBits(hBitStream, 0, 16);
    }
  } /* End of ADTS header */
void dabWrite_EndRawDataBlock(HANDLE_DAB hDab,
                          HANDLE_FDK_BITSTREAM hBs,
                          int *pBits)
{
    FDK_BITSTREAM bsWriter;
	INT crcIndex = 0;
	USHORT crcData;
	INT writeBits=0;
	INT writeBitsNonLastBlock=0;
	INT writeBitsLastBlock=0;
#if 1
    if (hDab->currentBlock == hDab->num_raw_blocks) {
    	//calculate byte-alignment before writing ID_FIL
    	if((FDKgetValidBits(hBs)+3) % 8){
    		writeBits = 8 - ((FDKgetValidBits(hBs)+3) % 8);
    	}

    	INT offset_end = hDab->subchannels_num*110*8 - 2*8 - 3;
    	writeBitsLastBlock = offset_end - FDKgetValidBits(hBs);
        dabWrite_FillRawDataBlock(hBs, writeBitsLastBlock);
		FDKsyncCache(hBs);
		//fprintf(stderr, "FIL-element written=%d\n", writeBitsLastBlock);
		writeBitsLastBlock=writeBits;
    }
#endif
	FDKwriteBits(hBs, 7, 3); //finalize AU: ID_END
	FDKsyncCache(hBs);
	//byte-align (if ID_FIL doesn't align it).
	if(FDKgetValidBits(hBs) % 8){
		writeBits = 8 - (FDKgetValidBits(hBs) % 8);
        FDKwriteBits(hBs, 0x00, writeBits);
		FDKsyncCache(hBs);
	}

	//fake-written bits alignment for last AU
	if (hDab->currentBlock == hDab->num_raw_blocks)
		writeBits=writeBitsLastBlock;

	INT frameLen = (FDKgetValidBits(hBs) - hDab->subFrameStartBit) >> 3;
	//fprintf(stderr, "frame=%d, offset writeBits=%d\n", frameLen, writeBits);

	FDK_ASSERT(FDKgetValidBits(hBs) % 8 == 0); //only aligned au's
    FDK_ASSERT(hDab->subchannels_num*110*8 >= FDKgetValidBits(hBs)+2*8); //don't overlap superframe

    FDKinitBitStream(&bsWriter, hBs->hBitBuf.Buffer, hBs->hBitBuf.bufSize, 0, BS_WRITER);
    FDKpushFor(&bsWriter, hDab->subFrameStartBit);
    FDKcrcReset(&hDab->crcInfo);
    hDab->crcIndex = FDKcrcStartReg(&hDab->crcInfo, &bsWriter, 0);
#if 0
    if (hDab->currentBlock == hDab->num_raw_blocks) {
		INT offset_size = hDab->subchannels_num*110*8 - 2*8 - FDKgetValidBits(hBs);
		//fprintf(stderr, "offset_size=%d\n", offset_size >> 3);
		FDKpushFor(hBs, offset_size);
    }
#endif

    FDKpushFor(&bsWriter, FDKgetValidBits(hBs) - hDab->subFrameStartBit);
	FDKcrcEndReg(&hDab->crcInfo,  &bsWriter, hDab->crcIndex);
	crcData = FDKcrcGetCRC(&hDab->crcInfo);
	//fprintf(stderr, "crcData = %04x\n", crcData);
    /* Write inverted CRC of current raw data block */
    FDKwriteBits(hBs, crcData ^ 0xffff, 16);
	FDKsyncCache(hBs);


    /* Write distance to current data block */
	if(hDab->currentBlock) {
		FDKinitBitStream(&bsWriter, hBs->hBitBuf.Buffer, hBs->hBitBuf.bufSize, 0, BS_WRITER);
	    FDKpushFor(&bsWriter, 24 + (hDab->currentBlock-1)*12);
		//fprintf(stderr, "FDKwriteBits() = %d\n", hDab->subFrameStartBit>>3);
		FDKwriteBits(&bsWriter, (hDab->subFrameStartBit>>3), 12);
		FDKsyncCache(&bsWriter);
	}
示例#5
0
static TRANSPORTDEC_ERROR transportDec_readHeader(
        HANDLE_TRANSPORTDEC hTp,
        HANDLE_FDK_BITSTREAM hBs,
        int syncLength,
        int ignoreBufferFullness,
        int *pRawDataBlockLength,
        int *pfTraverseMoreFrames,
        int *pSyncLayerFrameBits,
        int *pfConfigFound,
        int *pHeaderBits
        )
{
  TRANSPORTDEC_ERROR err = TRANSPORTDEC_OK;
  int rawDataBlockLength = *pRawDataBlockLength;
  int fTraverseMoreFrames = (pfTraverseMoreFrames != NULL) ? *pfTraverseMoreFrames : 0;
  int syncLayerFrameBits = (pSyncLayerFrameBits != NULL) ? *pSyncLayerFrameBits : 0;
  int fConfigFound = (pfConfigFound != NULL) ? *pfConfigFound : 0;
  int startPos;

  startPos = FDKgetValidBits(hBs);

  switch (hTp->transportFmt) {
    case TT_MP4_ADTS:
      if (hTp->numberOfRawDataBlocks <= 0)
      {
        int errC;

        hTp->globalFramePos = FDKgetValidBits(hBs);

        /* Parse ADTS header */
        err = adtsRead_DecodeHeader( &hTp->parser.adts, &hTp->asc[0], hBs, ignoreBufferFullness );
        if (err != TRANSPORTDEC_OK) {
          if (err != TRANSPORTDEC_NOT_ENOUGH_BITS) {
            err = TRANSPORTDEC_SYNC_ERROR;
          }
        } else {
          errC = hTp->callbacks.cbUpdateConfig(hTp->callbacks.cbUpdateConfigData, &hTp->asc[0]);
          if (errC != 0) {
            if (errC == TRANSPORTDEC_NEED_TO_RESTART) {
              err = TRANSPORTDEC_NEED_TO_RESTART;
              goto bail;
            } else {
              err = TRANSPORTDEC_SYNC_ERROR;
            }
          } else {
            fConfigFound = 1;
            hTp->numberOfRawDataBlocks = hTp->parser.adts.bs.num_raw_blocks+1;
          }
        }
      }
      else {
        /* Reset CRC because the next bits are the beginning of a raw_data_block() */
        FDKcrcReset(&hTp->parser.adts.crcInfo);
        hTp->parser.adts.bs.num_pce_bits = 0;
      }
      if (err == TRANSPORTDEC_OK) {
        hTp->numberOfRawDataBlocks--;
        rawDataBlockLength = adtsRead_GetRawDataBlockLength(&hTp->parser.adts, (hTp->parser.adts.bs.num_raw_blocks-hTp->numberOfRawDataBlocks));
        if (rawDataBlockLength <= 0) {
          /* No further frame traversal possible. */
          fTraverseMoreFrames = 0;
        }
        syncLayerFrameBits = (hTp->parser.adts.bs.frame_length<<3) - (startPos - FDKgetValidBits(hBs)) - syncLength;
        if (syncLayerFrameBits <= 0) {
          err = TRANSPORTDEC_SYNC_ERROR;
        }
      } else {
        hTp->numberOfRawDataBlocks = 0;
      }
      break;
    case TT_MP4_LOAS:
      if (hTp->numberOfRawDataBlocks <= 0)
      {
        syncLayerFrameBits = FDKreadBits(hBs, 13);
        hTp->parser.latm.m_audioMuxLengthBytes = syncLayerFrameBits;
        syncLayerFrameBits <<= 3;
      }
    case TT_MP4_LATM_MCP1:
    case TT_MP4_LATM_MCP0:
      if (hTp->numberOfRawDataBlocks <= 0)
      {
        hTp->globalFramePos = FDKgetValidBits(hBs);

        err = CLatmDemux_Read(
                hBs,
               &hTp->parser.latm,
                hTp->transportFmt,
               &hTp->callbacks,
                hTp->asc,
               &fConfigFound,
                ignoreBufferFullness);

        if (err != TRANSPORTDEC_OK) {
          if (err != TRANSPORTDEC_NOT_ENOUGH_BITS) {
            err = TRANSPORTDEC_SYNC_ERROR;
          }
        } else {
          hTp->numberOfRawDataBlocks = CLatmDemux_GetNrOfSubFrames(&hTp->parser.latm);
          if (hTp->transportFmt == TT_MP4_LOAS) {
            syncLayerFrameBits -= startPos - FDKgetValidBits(hBs) - (13);            
          }
        }
      } else {
        err = CLatmDemux_ReadPayloadLengthInfo(hBs, &hTp->parser.latm);
        if (err != TRANSPORTDEC_OK) {
          err = TRANSPORTDEC_SYNC_ERROR;
        }
      }
      if (err == TRANSPORTDEC_OK) {
        rawDataBlockLength = CLatmDemux_GetFrameLengthInBits(&hTp->parser.latm);
        hTp->numberOfRawDataBlocks--;
      } else {
        hTp->numberOfRawDataBlocks = 0;
      }
      break;
    default:
      {
        syncLayerFrameBits = 0;
      }
      break;
  }

bail:

  *pRawDataBlockLength = rawDataBlockLength;

  if (pHeaderBits != NULL) {
    *pHeaderBits += startPos - (INT)FDKgetValidBits(hBs);
  }
  if (pfConfigFound != NULL) {
    *pfConfigFound = fConfigFound;
  }

  if (pfTraverseMoreFrames != NULL) {
    *pfTraverseMoreFrames = fTraverseMoreFrames;
  }
  if  (pSyncLayerFrameBits != NULL) {
    *pSyncLayerFrameBits = syncLayerFrameBits;
  }
  if (pfConfigFound != NULL) {
    *pfConfigFound = fConfigFound;
  }

  return err;
}
示例#6
0
TRANSPORTDEC_ERROR adtsRead_DecodeHeader(
        HANDLE_ADTS           pAdts,
        CSAudioSpecificConfig *pAsc,
        HANDLE_FDK_BITSTREAM  hBs,
        const INT             ignoreBufferFullness
        )
{
  INT crcReg;

  INT valBits;
  INT cmp_buffer_fullness;
  int i, adtsHeaderLength;

  STRUCT_ADTS_BS bs;

#ifdef TP_PCE_ENABLE
  CProgramConfig oldPce;
  /* Store the old PCE temporarily. Maybe we'll need it later if we
     have channelConfig=0 and no PCE in this frame. */
  FDKmemcpy(&oldPce, &pAsc->m_progrConfigElement, sizeof(CProgramConfig));
#endif

  valBits = FDKgetValidBits(hBs);

#ifndef ANDROID_DEFAULT_CODE
  if (valBits <= ADTS_HEADERLENGTH) return TRANSPORTDEC_NOT_ENOUGH_BITS;
#endif

  /* adts_fixed_header */
  bs.mpeg_id           = FDKreadBits(hBs, Adts_Length_Id);
  bs.layer             = FDKreadBits(hBs, Adts_Length_Layer);
  bs.protection_absent = FDKreadBits(hBs, Adts_Length_ProtectionAbsent);
  bs.profile           = FDKreadBits(hBs, Adts_Length_Profile);
  bs.sample_freq_index = FDKreadBits(hBs, Adts_Length_SamplingFrequencyIndex);
  bs.private_bit       = FDKreadBits(hBs, Adts_Length_PrivateBit);
  bs.channel_config    = FDKreadBits(hBs, Adts_Length_ChannelConfiguration);
  bs.original          = FDKreadBits(hBs, Adts_Length_OriginalCopy);
  bs.home              = FDKreadBits(hBs, Adts_Length_Home);

  /* adts_variable_header */
  bs.copyright_id    = FDKreadBits(hBs, Adts_Length_CopyrightIdentificationBit);
  bs.copyright_start = FDKreadBits(hBs, Adts_Length_CopyrightIdentificationStart);
  bs.frame_length    = FDKreadBits(hBs, Adts_Length_FrameLength);
  bs.adts_fullness   = FDKreadBits(hBs, Adts_Length_BufferFullness);
  bs.num_raw_blocks  = FDKreadBits(hBs, Adts_Length_NumberOfRawDataBlocksInFrame);
  bs.num_pce_bits    = 0;

  adtsHeaderLength = ADTS_HEADERLENGTH;

  if (!bs.protection_absent) {
    FDKcrcReset(&pAdts->crcInfo);
    FDKpushBack(hBs, 56);   /* complete fixed and variable header! */
    crcReg = FDKcrcStartReg(&pAdts->crcInfo, hBs, 0);
    FDKpushFor(hBs, 56);
  }

  if (! bs.protection_absent && bs.num_raw_blocks>0) {
    for (i=0; i<bs.num_raw_blocks; i++) {
      pAdts->rawDataBlockDist[i] = (USHORT)FDKreadBits(hBs, 16);
      adtsHeaderLength += 16;
    }
    /* Change raw data blocks to delta values */
    pAdts->rawDataBlockDist[bs.num_raw_blocks] = bs.frame_length - 7 - bs.num_raw_blocks*2 - 2 ;
    for (i=bs.num_raw_blocks; i>0; i--) {
      pAdts->rawDataBlockDist[i] -= pAdts->rawDataBlockDist[i-1];
    }
  }

  /* adts_error_check */
  if (!bs.protection_absent)
  {
    USHORT crc_check;

    FDKcrcEndReg(&pAdts->crcInfo, hBs, crcReg);
    crc_check = FDKreadBits(hBs, Adts_Length_CrcCheck);
    adtsHeaderLength += Adts_Length_CrcCheck;

    pAdts->crcReadValue = crc_check;
    /* Check header CRC in case of multiple raw data blocks */
    if (bs.num_raw_blocks > 0) {
      if (pAdts->crcReadValue != FDKcrcGetCRC(&pAdts->crcInfo)) {
        return TRANSPORTDEC_CRC_ERROR;
      }
      /* Reset CRC for the upcoming raw_data_block() */
      FDKcrcReset(&pAdts->crcInfo);
    }
  }


  /* check if valid header */
  if (
      (bs.layer != 0) ||                          // we only support MPEG ADTS
      (bs.sample_freq_index >= 13)                // we only support 96kHz - 7350kHz
      ) {
    FDKpushFor(hBs, bs.frame_length * 8);   // try again one frame later
    return TRANSPORTDEC_UNSUPPORTED_FORMAT;
  }

  /* special treatment of id-bit */
  if ( (bs.mpeg_id == 0) && (pAdts->decoderCanDoMpeg4 == 0) )
  {
    /* MPEG-2 decoder cannot play MPEG-4 bitstreams */


    FDKpushFor(hBs, bs.frame_length * 8);  // try again one frame later
    return TRANSPORTDEC_UNSUPPORTED_FORMAT;
  }

  if (!ignoreBufferFullness)
  {
    cmp_buffer_fullness = bs.frame_length*8 + bs.adts_fullness*32*getNumberOfEffectiveChannels(bs.channel_config);


    /* Evaluate buffer fullness */
    if (bs.adts_fullness != 0x7FF)
    {
      if (pAdts->BufferFullnesStartFlag)
      {
        if ( valBits < cmp_buffer_fullness )
        {
          /* Condition for start of decoding is not fulfilled */

          /* The current frame will not be decoded */
          FDKpushBack(hBs, adtsHeaderLength);

          if ( (cmp_buffer_fullness+adtsHeaderLength) > ((TRANSPORTDEC_INBUF_SIZE<<3)-7) ) {
            return TRANSPORTDEC_SYNC_ERROR;
          } else {
            return TRANSPORTDEC_NOT_ENOUGH_BITS;
          }
        }
        else
        {
          pAdts->BufferFullnesStartFlag = 0;
        }
      }
    }
  }


  /* Get info from ADTS header */
  AudioSpecificConfig_Init(pAsc);
  pAsc->m_aot                    = (AUDIO_OBJECT_TYPE)(bs.profile + 1);
  pAsc->m_samplingFrequencyIndex = bs.sample_freq_index;
  pAsc->m_samplingFrequency      = SamplingRateTable[bs.sample_freq_index];
  pAsc->m_channelConfiguration   = bs.channel_config;
  pAsc->m_samplesPerFrame        = 1024;

#ifdef TP_PCE_ENABLE
  if (bs.channel_config == 0)
  {
    int pceBits = 0;
    UINT alignAnchor = FDKgetValidBits(hBs);
    
    if (FDKreadBits(hBs,3) == ID_PCE) {
      /* Got luck! Parse the PCE */
      int crcReg;
      crcReg = adtsRead_CrcStartReg(pAdts, hBs, 0);

      CProgramConfig_Read(&pAsc->m_progrConfigElement, hBs, alignAnchor);

      adtsRead_CrcEndReg(pAdts, hBs, crcReg);
      pceBits = alignAnchor - FDKgetValidBits(hBs);
      /* store the number of PCE bits */
      bs.num_pce_bits = pceBits;
    }
    else {
      /* No PCE in this frame! Push back the ID tag bits. */
      FDKpushBack(hBs,3);

      /* Encoders do not have to write a PCE in each frame.
         So if we already have a valid PCE we have to use it. */
      if (  oldPce.isValid
        && (bs.sample_freq_index == pAdts->bs.sample_freq_index)  /* we could compare the complete fixed header (bytes) here! */
        && (bs.channel_config    == pAdts->bs.channel_config) /* == 0 */
        && (bs.mpeg_id           == pAdts->bs.mpeg_id) )
      { /* Restore previous PCE which is still valid */
        FDKmemcpy(&pAsc->m_progrConfigElement, &oldPce, sizeof(CProgramConfig));
      }
      else if (bs.mpeg_id == 0) {
        /* If not it seems that we have a implicit channel configuration.
           This mode is not allowed in the context of ISO/IEC 14496-3.
           Skip this frame and try the next one. */
        FDKpushFor(hBs, (bs.frame_length<<3) - adtsHeaderLength - 3);
        return TRANSPORTDEC_UNSUPPORTED_FORMAT;
      }
      /* else {
         ISO/IEC 13818-7 implicit channel mapping is allowed.
         So just open the box of chocolates to see what we got.
      } */
    }
  }
#endif /* TP_PCE_ENABLE */

  /* Copy bit stream data struct to persistent memory now, once we passed all sanity checks above. */
  FDKmemcpy(&pAdts->bs, &bs, sizeof(STRUCT_ADTS_BS));

  return TRANSPORTDEC_OK;
}