| /* ------------------------------------------------------------------ |
| * 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: PVMP4AudioDecoderConfig |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: (1) Modified to decode AudioSpecificConfig for any frame number |
| pVars->bno |
| (2) Update the input and output descriptions |
| |
| Description: Eliminated search for ADIF header |
| |
| Description: Added support for AAC+ |
| |
| Who: Date: |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| pExt = pointer to the external interface structure. See the file |
| PVMP4AudioDecoder_API.h for a description of each field. |
| Data type of pointer to a tPVMP4AudioDecoderExternal |
| structure. |
| |
| pExt->pInputBuffer: pointer to input buffer containing input |
| bitstream |
| |
| pExt->inputBufferCurrentLength: number of bytes in the input buffer |
| |
| pExt->inputBufferUsedLength: number of bytes already consumed in |
| input buffer |
| |
| pExt->remainderBits: number of bits consumed in addition to |
| pExt->inputBufferUsedLength |
| |
| pMem = void pointer to hide the internal implementation of the library |
| It is cast back to a tDec_Int_File structure. This structure |
| contains information that needs to persist between calls to |
| this function, or is too big to be placed on the stack, even |
| though the data is only needed during execution of this function |
| Data type void pointer, internally pointer to a tDec_Int_File |
| structure. |
| |
| Local Stores/Buffers/Pointers Needed: None |
| (The memory set aside in pMem performs this task) |
| |
| Global Stores/Buffers/Pointers Needed: None |
| |
| Outputs: |
| status = 0 if no error occurred |
| MP4AUDEC_NONRECOVERABLE if a non-recoverable error occurred |
| MP4AUDEC_RECOVERABLE if a recoverable error occurred. |
| Presently a recoverable error does not exist, but this |
| was a requirement. |
| |
| |
| Pointers and Buffers Modified: |
| pMem contents are modified. |
| pExt: (more detail in the file PVMP4AudioDecoder_API.h) |
| inputBufferUsedLength - number of array elements used up by the stream. |
| remainderBits - remaining bits in the next UInt32 buffer |
| samplingRate - sampling rate in samples per sec |
| encodedChannels - channels found on the file (informative) |
| frameLength - length of the frame |
| |
| Local Stores Modified: None. |
| |
| Global Stores Modified: None. |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| PacketVideo Document # CCC-AUD-AAC-ERS-0003 |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| (1) ISO/IEC 14496-3: 1999(E) |
| subclause 1.6 |
| |
| ------------------------------------------------------------------------------ |
| 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 "s_tdec_int_file.h" |
| #include "ibstream.h" /* where #define INBUF_ARRAY_INDEX_SHIFT */ |
| #include "sfb.h" /* Where samp_rate_info[] is declared */ |
| |
| #include "get_audio_specific_config.h" |
| #include "pvmp4audiodecoder_api.h" /* Where this function is declared */ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; 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 |
| ----------------------------------------------------------------------------*/ |
| |
| OSCL_EXPORT_REF Int PVMP4AudioDecoderConfig( |
| tPVMP4AudioDecoderExternal *pExt, |
| void *pMem) |
| { |
| |
| UInt initialUsedBits; /* Unsigned for C55x */ |
| tDec_Int_File *pVars; /* Helper pointer */ |
| |
| Int status = MP4AUDEC_INCOMPLETE_FRAME; |
| |
| /* |
| * Initialize "helper" pointers to existing memory. |
| */ |
| pVars = (tDec_Int_File *)pMem; |
| /* |
| * Translate input buffer variables. |
| */ |
| pVars->inputStream.pBuffer = pExt->pInputBuffer; |
| |
| pVars->inputStream.inputBufferCurrentLength = |
| (UInt)pExt->inputBufferCurrentLength; |
| |
| pVars->inputStream.availableBits = |
| (UInt)(pExt->inputBufferCurrentLength << INBUF_ARRAY_INDEX_SHIFT); |
| |
| initialUsedBits = |
| (UInt)((pExt->inputBufferUsedLength << INBUF_ARRAY_INDEX_SHIFT) + |
| pExt->remainderBits); |
| |
| pVars->inputStream.usedBits = initialUsedBits; |
| |
| if (initialUsedBits <= pVars->inputStream.availableBits) |
| { |
| |
| /* |
| * Buffer is not overrun, then |
| * decode the AudioSpecificConfig() structure |
| */ |
| |
| pVars->aacConfigUtilityEnabled = false; /* set aac dec mode */ |
| |
| status = get_audio_specific_config(pVars); |
| |
| } |
| |
| byte_align(&pVars->inputStream); |
| |
| |
| if (status == SUCCESS) |
| { |
| |
| pVars->bno++; |
| |
| /* |
| * A possible improvement would be to set these values only |
| * when they change. |
| */ |
| pExt->samplingRate = |
| samp_rate_info[pVars->prog_config.sampling_rate_idx].samp_rate; |
| |
| /* |
| * we default to 2 channel, even for mono files, (where channels have same content) |
| * this is done to ensure support for enhanced aac+ with implicit signalling |
| */ |
| pExt->aacPlusEnabled = pVars->aacPlusEnabled; |
| |
| // pExt->encodedChannels = pVars->mc_info.nch; |
| |
| pExt->encodedChannels = 2; |
| |
| pExt->frameLength = pVars->frameLength; |
| #ifdef AAC_PLUS |
| pExt->aacPlusUpsamplingFactor = pVars->mc_info.upsamplingFactor; |
| #endif |
| |
| } |
| else |
| { |
| /* |
| * Default to nonrecoverable error status unless there is a Buffer overrun |
| */ |
| status = MP4AUDEC_INVALID_FRAME; |
| |
| if (pVars->inputStream.usedBits > pVars->inputStream.availableBits) |
| { |
| /* all bits were used but were not enough to complete parsing */ |
| pVars->inputStream.usedBits = pVars->inputStream.availableBits; |
| |
| status = MP4AUDEC_INCOMPLETE_FRAME; /* audio config too small */ |
| } |
| |
| } |
| |
| /* |
| * Translate from units of bits back into units of words. |
| */ |
| |
| pExt->inputBufferUsedLength = |
| pVars->inputStream.usedBits >> INBUF_ARRAY_INDEX_SHIFT; |
| |
| pExt->remainderBits = pVars->inputStream.usedBits & INBUF_BIT_MODULO_MASK; |
| |
| pVars->status = status; |
| |
| return (status); |
| |
| } /* PVMP4AudioDecoderDecodeFrame */ |
| |
