/* ------------------------------------------------------------------ * Copyright (C) 1998-2009 PacketVideo * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. * See the License for the specific language governing permissions * and limitations under the License. * ------------------------------------------------------------------- */ /* Filename: sbr_extract_extended_data.c ------------------------------------------------------------------------------ REVISION HISTORY Who: Date: MM/DD/YYYY Description: ------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS SBR_FRAME_DATA *hFrameData, Destination for extracted data of left channel SBR_FRAME_DATA *hFrameDataRight Destination for extracted data of right channel BIT_BUFFER hBitBuf pointer to bit buffer ------------------------------------------------------------------------------ FUNCTION DESCRIPTION Reads extension data from the bitstream The bitstream format allows up to 4 kinds of extended data element. Extended data may contain several elements, each identified by a 2-bit-ID. ------------------------------------------------------------------------------ REQUIREMENTS ------------------------------------------------------------------------------ REFERENCES SC 29 Software Copyright Licencing Disclaimer: This software module was originally developed by Coding Technologies and edited by - in the course of development of the ISO/IEC 13818-7 and ISO/IEC 14496-3 standards for reference purposes and its performance may not have been optimized. This software module is an implementation of one or more tools as specified by the ISO/IEC 13818-7 and ISO/IEC 14496-3 standards. ISO/IEC gives users free license to this software module or modifications thereof for use in products claiming conformance to audiovisual and image-coding related ITU Recommendations and/or ISO/IEC International Standards. ISO/IEC gives users the same free license to this software module or modifications thereof for research purposes and further ISO/IEC standardisation. Those intending to use this software module in products are advised that its use may infringe existing patents. ISO/IEC have no liability for use of this software module or modifications thereof. Copyright is not released for products that do not conform to audiovisual and image-coding related ITU Recommendations and/or ISO/IEC International Standards. The original developer retains full right to modify and use the code for its own purpose, assign or donate the code to a third party and to inhibit third parties from using the code for products that do not conform to audiovisual and image-coding related ITU Recommendations and/or ISO/IEC International Standards. This copyright notice must be included in all copies or derivative works. Copyright (c) ISO/IEC 2002. ------------------------------------------------------------------------------ PSEUDO-CODE ------------------------------------------------------------------------------ */ /*---------------------------------------------------------------------------- ; INCLUDES ----------------------------------------------------------------------------*/ #ifdef AAC_PLUS #include "sbr_extract_extended_data.h" #include "buf_getbits.h" #ifdef PARAMETRICSTEREO #include "ps_read_data.h" #endif /*---------------------------------------------------------------------------- ; MACROS ; Define module specific macros here ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; DEFINES ; Include all pre-processor statements here. Include conditional ; compile variables also. ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; LOCAL FUNCTION DEFINITIONS ; Function Prototype declaration ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; LOCAL STORE/BUFFER/POINTER DEFINITIONS ; Variable declaration - defined here and used outside this module ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; EXTERNAL FUNCTION REFERENCES ; Declare functions defined elsewhere and referenced in this module ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES ; Declare variables used in this module but defined elsewhere ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; FUNCTION CODE ----------------------------------------------------------------------------*/ void sbr_extract_extended_data(BIT_BUFFER * hBitBuf #ifdef PARAMETRICSTEREO /* Parametric Stereo Decoder */ , HANDLE_PS_DEC hParametricStereoDec #endif ) { Int32 extended_data; Int32 i; Int32 nBitsLeft; Int32 extension_id; extended_data = buf_get_1bit(hBitBuf); /* SI_SBR_EXTENDED_DATA_BITS */ if (extended_data) { Int32 cnt; cnt = buf_getbits(hBitBuf, SI_SBR_EXTENSION_SIZE_BITS); if (cnt == (1 << SI_SBR_EXTENSION_SIZE_BITS) - 1) { cnt += buf_getbits(hBitBuf, SI_SBR_EXTENSION_ESC_COUNT_BITS); } nBitsLeft = (cnt << 3); while (nBitsLeft > 7) { extension_id = buf_getbits(hBitBuf, SI_SBR_EXTENSION_ID_BITS); nBitsLeft -= SI_SBR_EXTENSION_ID_BITS; switch (extension_id) { #ifdef HQ_SBR #ifdef PARAMETRICSTEREO /* * Parametric Coding supports the Transient, Sinusoidal, Noise, and * Parametric Stereo tools (MPEG4). * 3GPP use aac+ hq along with ps for enhanced aac+ * The PS tool uses complex-value QMF data, therefore can not be used * with low power version of aac+ */ case EXTENSION_ID_PS_CODING: if (hParametricStereoDec != NULL) { if (!hParametricStereoDec->psDetected) { /* parametric stereo detected */ hParametricStereoDec->psDetected = 1; } nBitsLeft -= ps_read_data(hParametricStereoDec, hBitBuf, nBitsLeft); } break; #endif #endif case 0: default: /* An unknown extension id causes the remaining extension data * to be skipped */ cnt = nBitsLeft >> 3; /* number of remaining bytes */ for (i = 0; i < cnt; i++) { buf_getbits(hBitBuf, 8); } nBitsLeft -= (cnt << 3); } } /* read fill bits for byte alignment */ buf_getbits(hBitBuf, nBitsLeft); } } #endif