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Diffstat (limited to 'media/libstagefright/codecs/aacdec/get_ele_list.cpp')
| -rw-r--r-- | media/libstagefright/codecs/aacdec/get_ele_list.cpp | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/aacdec/get_ele_list.cpp b/media/libstagefright/codecs/aacdec/get_ele_list.cpp new file mode 100644 index 0000000..0534c13 --- /dev/null +++ b/media/libstagefright/codecs/aacdec/get_ele_list.cpp @@ -0,0 +1,243 @@ +/* ------------------------------------------------------------------ + * 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 */ + |