| /* ------------------------------------------------------------------ |
| * 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_ele_list.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 PacketVideo standard, rename variables. |
| |
| Description: Add own header file, make pInputStream second param for speed. |
| |
| Description: Changes per code review: |
| 1) Include header file |
| 2) Convert to count down |
| 3) Add return (not in review) |
| |
| Description: |
| (1) Updated copyright header |
| (2) Replaced include of "interface.h" with "e_ProgConfig.h" |
| |
| Description: Replace some instances of getbits to get9_n_lessbits |
| when the number of bits read is 9 or less and get1bits |
| when only 1 bit is read. |
| |
| Who: Date: |
| Description: |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| pElementList = pointer to an EleList structure - only the field num_ele |
| needs to be set. Data type pointer to EleList. |
| |
| pInputStream = pointer to a BITS structure, used by the function getbits |
| to provide data. Data type pointer to BITS |
| |
| enableCPE = boolean value indicating the area to be read contains |
| a channel pair element field. Data type Bool |
| |
| |
| Local Stores/Buffers/Pointers Needed: None |
| |
| Global Stores/Buffers/Pointers Needed: None |
| |
| Outputs: None |
| |
| Pointers and Buffers Modified: |
| pElementList contents are updated with information pertaining to channel |
| configuration. |
| |
| pInputBuffer contents are updated to the next location to be read from |
| the input stream. |
| |
| Local Stores Modified: None |
| |
| Global Stores Modified: None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function is called several times by get_prog_config() to read in part of |
| the program configuration data related to channel setup. |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| This function shall not have 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 |
| |
| elementCount = pElementList->num_ele; |
| |
| FOR (index = 0; index < elementCount; index++) |
| IF (enableCPE != FALSE) THEN |
| pElementList->ele_is_cpe[index] = |
| getbits(LEN_ELE_IS_CPE, pInputStream); |
| ELSE |
| pElementList->ele_is_cpe[index] = 0; |
| END IF |
| |
| pElementList->ele_tag[index] = getbits(LEN_TAG, pInputStream); |
| |
| END FOR |
| |
| RETURNS nothing |
| |
| ------------------------------------------------------------------------------ |
| 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_elelist.h" |
| #include "s_bits.h" |
| #include "e_progconfigconst.h" |
| #include "ibstream.h" |
| #include "get_ele_list.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 |
| ----------------------------------------------------------------------------*/ |
| void get_ele_list( |
| EleList *pElementList, |
| BITS *pInputStream, |
| const Bool enableCPE) |
| { |
| Int index; |
| Int *pEleIsCPE; |
| Int *pEleTag; |
| |
| pEleIsCPE = &pElementList->ele_is_cpe[0]; |
| pEleTag = &pElementList->ele_tag[0]; |
| |
| for (index = pElementList->num_ele; index > 0; index--) |
| { |
| if (enableCPE != FALSE) |
| { |
| *pEleIsCPE++ = get1bits(/*LEN_ELE_IS_CPE, */pInputStream); |
| } |
| else |
| { |
| *pEleIsCPE++ = FALSE; |
| } |
| |
| *pEleTag++ = get9_n_lessbits(LEN_TAG, pInputStream); |
| |
| } /* end for (index) */ |
| |
| return; |
| |
| } /* end get_ele_list */ |
| |
