| /* ------------------------------------------------------------------ |
| * 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_adif_header.c |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Modified from original shareware code |
| |
| Description: Modified to pass variables by reference to eliminate use |
| of global variables. |
| |
| Description: Change to PV template, remove default config parameter, |
| move some functionality into get_prog_config(). |
| |
| Description: Update per code review |
| 1) Add parameter pScratchPCE |
| 2) Change way ADIF_ID is read in. |
| 3) Fix comments |
| 4) ADD a test for status != SUCCESS in loop. |
| |
| Description: The ADIF_Header has now been delegated to the "scratch memory" |
| union. This change inside s_tDec_Int_File.h had to be reflected here also. |
| |
| Description: Updated the SW template to include the full pathname to the |
| source file and a slightly modified copyright header. |
| |
| Who: Date: |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| pVars = pointer to the structure that contains the current state |
| of this instance of the library, of data type pointer to |
| tDec_Int_File |
| |
| pScratchPCE = pointer to a ProgConfig structure used as scratch in the |
| the function get_prog_config. of data type pointer to |
| ProgConfig |
| |
| Local Stores/Buffers/Pointers Needed: None |
| |
| Global Stores/Buffers/Pointers Needed: None |
| |
| Outputs: |
| The function returns 0 if no error occurred, non-zero otherwise. |
| |
| Pointers and Buffers Modified: |
| pVars->adif_header contents are updated with the some of the ADIF header |
| contents |
| pVars->tempProgConfig contents are overwritten with last PCE found, |
| which is most likely the first one found. |
| pVars->prog_config contents are updated with the first PCE found. |
| pVars->inputStream contents are modify in such a way that the |
| stream is moved further along in the buffer. |
| pVars->SFBWidth128 contents may be updated. |
| pVars->winSeqInfo contents may be updated. |
| pScratchPCE contents may be updated. |
| |
| Local Stores Modified: None |
| |
| Global Stores Modified: None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function reads in the ADIF Header found at the front of ADIF streams. |
| If the header is not found an error is returned. An ADIF header can contain |
| from zero to sixteen program configuration elements (PCE). This function, and |
| the rest of the library, saves and uses the first PCE found. |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| Function shall not use static or global variables. |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| (1) ISO/IEC 13818-7:1997 Titled "Information technology - Generic coding |
| of moving pictures and associated audio information - Part 7: Advanced |
| Audio Coding (AAC)", Table 6.21 - Syntax of program_config_element(), |
| page 16, and section 8.5 "Program Config Element (PCE)", page 30. |
| |
| (2) MPEG-2 NBC Audio Decoder |
| "This software module was originally developed by AT&T, Dolby |
| Laboratories, Fraunhofer Gesellschaft IIS in the course of development |
| of the MPEG-2 NBC/MPEG-4 Audio standard ISO/IEC 13818-7, 14496-1,2 and |
| 3. This software module is an implementation of a part of one or more |
| MPEG-2 NBC/MPEG-4 Audio tools as specified by the MPEG-2 NBC/MPEG-4 |
| Audio standard. ISO/IEC gives users of the MPEG-2 NBC/MPEG-4 Audio |
| standards free license to this software module or modifications thereof |
| for use in hardware or software products claiming conformance to the |
| MPEG-2 NBC/MPEG-4 Audio standards. Those intending to use this software |
| module in hardware or software products are advised that this use may |
| infringe existing patents. The original developer of this software |
| module and his/her company, the subsequent editors and their companies, |
| and ISO/IEC have no liability for use of this software module or |
| modifications thereof in an implementation. Copyright is not released |
| for non MPEG-2 NBC/MPEG-4 Audio conforming products.The original |
| developer retains full right to use the code for his/her own purpose, |
| assign or donate the code to a third party and to inhibit third party |
| from using the code for non MPEG-2 NBC/MPEG-4 Audio conforming products. |
| This copyright notice must be included in all copies or derivative |
| works." |
| Copyright(c)1996. |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| CALL getbits( |
| neededBits = 2 * LEN_BYTE, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| RETURNING( theIDFromFile ) |
| |
| CALL getbits( |
| neededBits = 2 * LEN_BYTE, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| RETURNING( temp ) |
| |
| theIDFromFile = (theIDFromFile << (2*LEN_BYTE)) | temp; |
| |
| IF (theIDFromFile != ADIF_ID) |
| THEN |
| |
| pInputStream->usedBits -= (4 * LEN_BYTE); |
| |
| status = -1; |
| ELSE |
| CALL getbits( |
| neededBits = LEN_COPYRT_PRES, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| RETURNING( temp ) |
| |
| IF (temp != FALSE) THEN |
| FOR (i = LEN_COPYRT_ID; i > 0; i--) |
| CALL getbits( |
| neededBits = LEN_BYTE, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| |
| END FOR |
| END IF |
| |
| CALL getbits( |
| neededBits = LEN_ORIG + LEN_HOME, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| |
| CALL getbits( |
| neededBits = LEN_BS_TYPE, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| RETURNING( bitStreamType ) |
| |
| CALL getbits( |
| neededBits = LEN_BIT_RATE, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| RETURNING( pHeader->bitrate ) |
| |
| CALL getbits( |
| neededBits = LEN_NUM_PCE, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| RETURNING( numConfigElementsMinus1 ) |
| |
| FOR ( i = numConfigElementsMinus1; |
| (i >= 0) && (status == SUCCESS); |
| i--) |
| |
| IF (bitStreamType == CONSTANT_RATE_BITSTREAM) THEN |
| CALL getbits( |
| neededBits = LEN_ADIF_BF, |
| pInputStream = pInputStream) |
| MODIFYING( pInputStream ) |
| END IF |
| |
| CALL get_prog_config( |
| pVars = pVars) |
| MODIFYING( pVars->prog_config ) |
| RETURNING( status ) |
| |
| END FOR |
| END IF |
| |
| 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_adif_const.h" |
| |
| #include "s_progconfig.h" |
| #include "s_adif_header.h" |
| #include "s_bits.h" |
| #include "s_mc_info.h" |
| #include "s_frameinfo.h" |
| #include "s_tdec_int_file.h" |
| |
| #include "get_prog_config.h" |
| #include "ibstream.h" |
| |
| #include "get_adif_header.h" |
| |
| /*---------------------------------------------------------------------------- |
| ; MACROS |
| ; Define module specific macros here |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; DEFINES |
| ; Include all pre-processor statements here. Include conditional |
| ; compile variables also. |
| ----------------------------------------------------------------------------*/ |
| |
| /* |
| * This constant is simply the characters 'A' 'D' 'I' 'F' compressed into |
| * a UInt32. Any possible endian problems that exist must be solved by |
| * the function that fills the buffer and getbits(), or this constant and |
| * the rest of the bit stream will not work. |
| */ |
| #define ADIF_ID (0x41444946) |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL FUNCTION DEFINITIONS |
| ; Function Prototype declaration |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL VARIABLE DEFINITIONS |
| ; Variable declaration - defined here and used outside this module |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; EXTERNAL FUNCTION REFERENCES |
| ; Declare functions defined elsewhere and referenced in this module |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; EXTERNAL VARIABLES REFERENCES |
| ; Declare variables used in this module but defined elsewhere |
| ----------------------------------------------------------------------------*/ |
| |
| Int get_adif_header( |
| tDec_Int_File *pVars, |
| ProgConfig *pScratchPCE) |
| { |
| Int i; |
| UInt32 temp; |
| Int numConfigElementsMinus1; |
| Int bitStreamType; |
| UInt32 theIDFromFile; |
| |
| BITS *pInputStream = &pVars->inputStream; |
| ADIF_Header *pHeader = &pVars->scratch.adif_header; |
| Int status = SUCCESS; |
| |
| /* |
| * The ADIF_ID field is 32 bits long, one more than what getbits() can |
| * do, so read the field in two parts. There is no point in saving the |
| * string - it either matches or it does not. If it matches, it must |
| * have been 'ADIF' |
| */ |
| |
| theIDFromFile = get17_n_lessbits((2 * LEN_BYTE), pInputStream); |
| |
| temp = get17_n_lessbits((2 * LEN_BYTE), pInputStream); |
| |
| theIDFromFile = (theIDFromFile << (2 * LEN_BYTE)) | temp; |
| |
| |
| if (theIDFromFile != ADIF_ID) |
| { |
| /* |
| * Rewind the bit stream pointer so a search for ADTS header |
| * can start at the beginning. |
| */ |
| |
| pInputStream->usedBits -= (4 * LEN_BYTE); |
| |
| /* |
| * The constant in the next line needs to be updated when |
| * error handling method is determined. |
| */ |
| status = -1; |
| } |
| else |
| { |
| /* |
| * To save space, the unused fields are read in, but not saved. |
| */ |
| |
| /* copyright string */ |
| temp = |
| get1bits(/* LEN_COPYRT_PRES,*/ |
| pInputStream); |
| |
| if (temp != FALSE) |
| { |
| /* |
| * Read in and ignore the copyright string. If restoring |
| * watch out for count down loop. |
| */ |
| |
| for (i = LEN_COPYRT_ID; i > 0; i--) |
| { |
| get9_n_lessbits(LEN_BYTE, |
| pInputStream); |
| } /* end for */ |
| |
| /* |
| * Make sure to terminate the string with '\0' if restoring |
| * the the copyright string. |
| */ |
| |
| } /* end if */ |
| |
| /* Combine the original/copy and fields into one call */ |
| get9_n_lessbits( |
| LEN_ORIG + LEN_HOME, |
| pInputStream); |
| |
| bitStreamType = |
| get1bits(/* LEN_BS_TYPE,*/ |
| pInputStream); |
| |
| pHeader->bitrate = |
| getbits( |
| LEN_BIT_RATE, |
| pInputStream); |
| |
| /* |
| * Read in all the Program Configuration Elements. |
| * For this library, only one of the up to 16 possible PCE's will be |
| * saved. Since each PCE must be read, a temporary PCE structure is |
| * used, and if that PCE is the one to use, it is copied into the |
| * single PCE. This is done inside of get_prog_config() |
| */ |
| |
| numConfigElementsMinus1 = get9_n_lessbits(LEN_NUM_PCE, |
| pInputStream); |
| |
| for (i = numConfigElementsMinus1; |
| (i >= 0) && (status == SUCCESS); |
| i--) |
| { |
| /* |
| * For ADIF contant bit rate streams, the _encoder_ buffer |
| * fullness is transmitted. This version of an AAC decoder has |
| * no use for this variable; yet it must be read in to move |
| * the bitstream pointers. |
| */ |
| |
| if (bitStreamType == CONSTANT_RATE_BITSTREAM) |
| { |
| getbits( |
| LEN_ADIF_BF, |
| pInputStream); |
| } /* end if */ |
| |
| pVars->adif_test = 1; |
| /* Get one program configuration element */ |
| status = |
| get_prog_config( |
| pVars, |
| pScratchPCE); |
| |
| #ifdef AAC_PLUS |
| |
| /* |
| * For implicit signalling, no hint that sbr or ps is used, so we need to |
| * check the sampling frequency of the aac content, if lesser or equal to |
| * 24 KHz, by defualt upsample, otherwise, do nothing |
| */ |
| if ((pVars->prog_config.sampling_rate_idx >= 6) && (pVars->aacPlusEnabled == true) && |
| pVars->mc_info.audioObjectType == MP4AUDIO_AAC_LC) |
| { |
| pVars->mc_info.upsamplingFactor = 2; |
| pVars->prog_config.sampling_rate_idx -= 3; |
| pVars->mc_info.sbrPresentFlag = 1; |
| pVars->sbrDecoderData.SbrChannel[0].syncState = UPSAMPLING; |
| pVars->sbrDecoderData.SbrChannel[1].syncState = UPSAMPLING; |
| } |
| #endif |
| |
| |
| |
| } /* end for */ |
| |
| |
| } /* end 'else' of --> if (theIDFromFile != ADIF_ID) */ |
| |
| return status; |
| |
| } /* end get_adif_header */ |
