| /* ------------------------------------------------------------------ |
| * 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. |
| * ------------------------------------------------------------------- |
| */ |
| /* |
| |
| Pathname: get_GA_specific_config.c |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Modified per review comments |
| |
| Description: Change getbits.h to ibstream.h |
| |
| Description: (1) use enum type for audioObjectType (2) update revision history |
| |
| Description: Updated the SW template to include the full pathname to the |
| source file and a slightly modified copyright header. |
| |
| Description: Updated to use scratch memory for the temporary prog config. |
| |
| Description: Replace some instances of getbits to get1bits |
| when only 1 bit is read. |
| |
| Who: Date: |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| pVars = pointer to the structure that holds all information for |
| this instance of the library. pVars->prog_config |
| pVars->mc_info, pVars->pWinSeqInfo, pVars->SFBWidth128 |
| are needed for calling set_mc_info. |
| Data type pointer to tDec_Int_File |
| |
| channel_config = variable that indicates the channel configuration |
| information, in this decoder library, only values |
| 0, 1, and 2 are allowed. |
| Data type UInt |
| |
| audioObjectType = variable that indicates the Audio Object Type. |
| Data type UInt. |
| |
| pInputStream = pointer to a BITS structure that holds information |
| regarding the input stream. |
| |
| Local Stores/Buffers/Pointers Needed: |
| None |
| |
| Global Stores/Buffers/Pointers Needed: |
| None |
| |
| Outputs: |
| status = 0 if success |
| 1 otherwise |
| |
| Pointers and Buffers Modified: |
| pVars->mc_info contents are updated with channel information. |
| if infoinit is called within set_mc_info, then |
| pVars->pWinSeqInfo contents are updated with window information. |
| pVars->SFBWidth128 contents are updated with scale factor band width data. |
| |
| Local Stores Modified: |
| None |
| |
| Global Stores Modified: |
| None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function takes the sampling_rate_idx, channel_config, and |
| audioObjectType from AudioSpecificConfig() and set the decoder configuration |
| necessary for the decoder to decode properly. |
| It also reads the bitstream for frame length, scalable bitstream information |
| and extension information to General Audio defined in MPEG-4 phase 1 |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| This function shall not use global variables |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| (1) ISO/IEC 14496-3: 1999(E) |
| Part 3 |
| Subpart 1 p18 1.6 Interface to MPEG-4 Systems |
| Subpart 4 p13 4.4.1 GA Specific Configuration |
| Amendment p10 6.2.1 AudioSpecificInfo |
| Amendment p78 8.2 Decoder configuration (GASpecificConfig) |
| |
| (2) AAC DecoderSpecificInfo Information |
| PacketVideo descriptions - San Diego |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| frameLenFlag = CALL getbits( |
| neededBits = LEN_FRAME_LEN_FLAG, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (frameLenFlag) |
| |
| dependsOnCoreCoder = CALL getbits( |
| neededBits = LEN_DEPEND_ON_CORE, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (dependsOnCoreCoder) |
| |
| IF (dependsOnCoreCoder != FALSE) |
| THEN |
| coreCoderDelay = CALL getbits( |
| neededBits = LEN_CORE_DELAY, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (coreCoderDelay) |
| ENDIF |
| |
| extFlag = CALL getbits( |
| neededBits = LEN_EXT_FLAG, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (extFlag) |
| |
| IF (channel_config == 0) |
| THEN |
| status = CALL get_prog_config( |
| pVars = pVars, |
| pScratchPCE = &pVars->scratch_prog_config); |
| MODIFYING (pVars, pScratchPCE) |
| RETURNING (status) |
| |
| ELSE |
| channel_config--; |
| pVars->prog_config.front.ele_is_cpe[0] = channel_config; |
| pVars->prog_config.front.ele_tag[0] = 0; |
| |
| status = CALL set_mc_info( |
| pMC_Info = &(pVars->mc_info), |
| audioObjectType = audioObjectType, |
| sampling_rate_idx = pVars->prog_config.sampling_rate_idx, |
| tag = pVars->prog_config.front.ele_tag[0], |
| is_cpe = pVars->prog_config.front.ele_is_cpe[0], |
| pWinSeqInfo = pVars->pWinSeqInfo, |
| sfbwidth128 = pVars->SFBWidth128); |
| MODIFYING (pMC_Info, pWinSeqInfo, sfbwidth128) |
| RETURNING (SUCCESS) |
| ENDIF |
| |
| IF ((audioObjectType == MP4AUDIO_AAC_SCALABLE) OR |
| (audioObjectType == MP4AUDIO_ER_AAC_SCALABLE)) |
| THEN |
| layer_num = CALL getbits( |
| neededBits = LEN_LAYER_NUM, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (layer_num) |
| |
| status = 1; |
| ENDIF |
| |
| IF (extFlag != FALSE) |
| THEN |
| IF (audioObjectType == MP4AUDIO_ER_BSAC) |
| THEN |
| numOfSubFrame = CALL getbits( |
| neededBits = LEN_SUB_FRAME, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (numOfSubFrame) |
| |
| layer_len = CALL getbits( |
| neededBits = LEN_LAYER_LEN, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (layer_len) |
| |
| ENDIF |
| |
| IF (((audioObjectType > 16) AND (audioObjectType < 22)) OR |
| (audioObjectType == 23)) |
| THEN |
| aacSectionDataResilienceFlag = |
| CALL getbits( |
| neededBits = LEN_SECT_RES_FLAG, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (aacSectionDataResilienceFlag) |
| |
| aacScalefactorDataResilienceFlag = |
| CALL getbits( |
| neededBits = LEN_SFB_RES_FLAG, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (aacScalefactorDataResilienceFlag) |
| |
| aacSpectralDataResilienceFlag = |
| CALL getbits( |
| neededBits = LEN_SPEC_RES_FLAG, |
| pInputStream = pInputStream); |
| MODIFYING (pInputStream) |
| RETURNING (aacSpectralDataResilienceFlag) |
| ENDIF |
| |
| status = 1; |
| |
| ENDIF |
| |
| RETURN status; |
| |
| ------------------------------------------------------------------------------ |
| RESOURCES USED |
| When the code is written for a specific target processor the |
| the resources used should be documented below. |
| |
| STACK USAGE: [stack count for this module] + [variable to represent |
| stack usage for each subroutine called] |
| |
| where: [stack usage variable] = stack usage for [subroutine |
| name] (see [filename].ext) |
| |
| DATA MEMORY USED: x words |
| |
| PROGRAM MEMORY USED: x words |
| |
| CLOCK CYCLES: [cycle count equation for this module] + [variable |
| used to represent cycle count for each subroutine |
| called] |
| |
| where: [cycle count variable] = cycle count for [subroutine |
| name] (see [filename].ext) |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| #include "pv_audio_type_defs.h" |
| #include "e_mp4ff_const.h" |
| #include "e_tmp4audioobjecttype.h" |
| #include "s_tdec_int_file.h" |
| #include "get_ga_specific_config.h" |
| #include "set_mc_info.h" |
| #include "get_prog_config.h" |
| #include "ibstream.h" |
| |
| /*---------------------------------------------------------------------------- |
| ; 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 |
| ----------------------------------------------------------------------------*/ |
| Int get_GA_specific_config( |
| tDec_Int_File * const pVars, |
| BITS *pInputStream, |
| UInt channel_config, |
| const tMP4AudioObjectType audioObjectType |
| ) |
| { |
| |
| Int status = SUCCESS; |
| UInt dependsOnCoreCoder; |
| /* Int coreCoderDelay; */ |
| UInt extFlag; |
| |
| /* These variables are left for future implementation */ |
| /* UInt layer_num; */ |
| /* UInt numOfSubFrame; */ |
| /* UInt layer_len; */ |
| /* UInt aacSectionDataResilienceFlag; */ |
| /* UInt aacScalefactorDataResilienceFlag; */ |
| /* UInt aacSpectralDataResilienceFlag; */ |
| Int extFlag3; |
| |
| /* |
| * frame length flag == 0, 1024 samples/frame |
| * frame length flag == 1, 960 samples/frame |
| */ |
| get1bits(/* LEN_FRAME_LEN_FLAG,*/ |
| pInputStream); |
| |
| /* |
| * dependsOnCoreCoder == 1, core coder has different sampling rate |
| * in a scalable bitstream |
| */ |
| dependsOnCoreCoder = |
| get1bits(/* LEN_DEPEND_ON_CORE,*/ |
| pInputStream); |
| |
| if (dependsOnCoreCoder != FALSE) |
| { |
| /*coreCoderDelay = |
| * getbits( |
| * LEN_CORE_DELAY, |
| * pInputStream); |
| */ |
| |
| status = 1; /* do not support scalable coding in this release */ |
| } |
| |
| /* |
| * extension flag indicates if Amendment 1 objects are used or not |
| * extension flag == 0 objects = 1, 2, 3, 4, 6, 7 |
| * extension flag == 1 objects = 17, 19, 20, 21, 22, 23 |
| */ |
| extFlag = get1bits(pInputStream); /* LEN_EXT_FLAG,*/ |
| |
| |
| /* Force checks for implicit channel configuration */ |
| pVars->mc_info.implicit_channeling = 1; |
| |
| if (status == SUCCESS) |
| { |
| |
| if (channel_config == 0) |
| { |
| status = get_prog_config(pVars, |
| &pVars->scratch.scratch_prog_config); |
| |
| if (status != SUCCESS) |
| { |
| pVars->prog_config.front.ele_is_cpe[0] = 0; /* default to mono */ |
| pVars->mc_info.nch = 1; |
| pVars->prog_config.front.ele_tag[0] = 0; |
| |
| status = SUCCESS; |
| } |
| } |
| else |
| { |
| /* |
| * dummy tag = 0 and |
| * set up decoding configurations |
| */ |
| channel_config--; |
| pVars->prog_config.front.ele_is_cpe[0] = channel_config; |
| pVars->prog_config.front.ele_tag[0] = 0; |
| |
| status = |
| set_mc_info( |
| &(pVars->mc_info), |
| audioObjectType, /* previously profile */ |
| pVars->prog_config.sampling_rate_idx, |
| pVars->prog_config.front.ele_tag[0], |
| pVars->prog_config.front.ele_is_cpe[0], |
| pVars->winmap, /*pVars->pWinSeqInfo,*/ |
| pVars->SFBWidth128); |
| |
| } /* if (channel_config) */ |
| |
| } /* if(status) */ |
| |
| /* |
| * This layer_num is not found in ISO/IEC specs, |
| * but it is defined in San Diego spec for scalable bitstream |
| */ |
| if ((audioObjectType == MP4AUDIO_AAC_SCALABLE) || |
| (audioObjectType == MP4AUDIO_ER_AAC_SCALABLE)) |
| { |
| /*layer_num = |
| * getbits( |
| * LEN_LAYER_NUM, |
| * pInputStream); |
| */ |
| |
| status = 1; /* for this release only */ |
| } |
| |
| if (extFlag) |
| { |
| /* |
| * currently do not implement these functionalities |
| * defined in Amendment 1 |
| * keep it here for future release |
| */ |
| if (audioObjectType == MP4AUDIO_ER_BSAC) |
| { |
| status = 1; /* NOT SUPPORTED */ |
| /* |
| numOfSubFrame = getbits( LEN_SUB_FRAME, pInputStream); |
| |
| layer_len = getbits( LEN_LAYER_LEN, pInputStream); |
| */ |
| } |
| |
| /* |
| * The following code is equivalent to |
| * if ((audioObjectType == 17) || (audioObjectType == 18) || |
| * (audioObjectType == 19) || (audioObjectType == 20) || |
| * (audioObjectType == 21) || (audioObjectType == 23)) |
| */ |
| |
| if (((audioObjectType > 16) && (audioObjectType < 22)) || |
| (audioObjectType == 23)) |
| { |
| status = 1; /* NOT SUPPORTED */ |
| /* |
| aacSectionDataResilienceFlag = getbits( LEN_SECT_RES_FLAG, |
| pInputStream); |
| |
| aacScalefactorDataResilienceFlag = getbits( LEN_SCF_RES_FLAG, |
| pInputStream); |
| |
| aacSpectralDataResilienceFlag = getbits( LEN_SPEC_RES_FLAG, |
| pInputStream); |
| */ |
| } |
| /* |
| * this flag is tbd in version 3 of ISO/IEC spec |
| * if the encoder generates this bit, then it has to be read |
| * current adif2mp4ff does not write this bit. If this bit is to |
| * be read, it can be done by the following code: |
| */ |
| |
| extFlag3 = get1bits(pInputStream); /* LEN_EXT_FLAG3 */ |
| |
| if (extFlag3) |
| { |
| status = 1; /* NOT SUPPORTED */ |
| } |
| |
| } |
| |
| return status; |
| } |
