| /* ------------------------------------------------------------------ |
| * 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: ./src/deinterleave.c |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Modified from original shareware code |
| |
| Description: (1) Modified with new template, rename variables |
| (2) Removed for-loop to calculate win_inc, win_inc = SN2 (128) |
| (3) Replaced for-loop with memcpy |
| (4) Converted Int16 -> Int |
| |
| Description: Modified per review comments |
| |
| Who: Date: |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| interleaved = input array that contains interleaved coefficients |
| Data Type Int |
| |
| deinterleaved = output array that will be updated with de-interleaved |
| coefficients of input array. Data Type Int |
| |
| pFrameInfo = pointer to structure that holds information of current |
| frame. Data Type FrameInfo |
| |
| Local Stores/Buffers/Pointers Needed: |
| None |
| |
| Global Stores/Buffers/Pointers Needed: |
| None |
| |
| Outputs: |
| None |
| |
| Pointers and Buffers Modified: |
| deinterleaved contents updated with de-interleaved coefficients from |
| the input array: interleaved |
| |
| Local Stores Modified: |
| None |
| |
| Global Stores Modified: |
| None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function performs the deinterleaving across all short windows in |
| each group |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| This function should replace the contents of pDeinterleaved with the |
| de-interleaved 1024 coefficients of one frame |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| (1) 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. |
| |
| (2) ISO/IEC 14496-3: 1999(E) |
| Subpart 4 p78 quant_to_spec |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| pInterleaved = interleaved; |
| pDeinterleaved = deinterleaved; |
| |
| pSfbPerWin = pFrameInfo->sfb_per_win; |
| ngroups = pFrameInfo->num_groups; |
| pGroupLen = pFrameInfo->group_len; |
| |
| pGroup = pDeinterleaved; |
| |
| FOR (group = ngroups; group > 0; group--) |
| |
| pSfbWidth = pFrameInfo->sfb_width_128; |
| sfb_inc = 0; |
| pStart = pInterleaved; |
| |
| FOR (sfb = pSfbPerWin[ngroups-group]; sfb > 0; sfb--) |
| |
| pWin = pGroup; |
| |
| FOR (win = pGroupLen[ngroups-group]; win > 0; win--) |
| |
| pDeinterleaved = pWin + sfb_inc; |
| |
| pv_memcpy( |
| pDeinterleaved, |
| pInterleaved, |
| *pSfbWidth*sizeof(*pInterleaved)); |
| |
| pInterleaved += *pSfbWidth; |
| |
| pWin += SN2; |
| |
| ENDFOR (win) |
| |
| sfb_inc += *pSfbWidth++; |
| |
| ENDFOR (sfb) |
| |
| pGroup += (pInterleaved - pStart); |
| |
| ENDFOR (group) |
| |
| ------------------------------------------------------------------------------ |
| 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 "huffman.h" |
| #include "aac_mem_funcs.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 deinterleave( |
| Int16 interleaved[], |
| Int16 deinterleaved[], |
| FrameInfo *pFrameInfo) |
| { |
| |
| Int group; /* group index */ |
| Int sfb; /* scalefactor band index */ |
| Int win; /* window index */ |
| Int16 *pGroup; |
| Int16 *pWin; |
| Int16 *pStart; |
| Int16 *pInterleaved; |
| Int16 *pDeinterleaved; |
| Int sfb_inc; |
| |
| Int ngroups; |
| Int *pGroupLen; |
| Int *pSfbPerWin; |
| Int *pSfbWidth; |
| |
| pInterleaved = interleaved; |
| pDeinterleaved = deinterleaved; |
| |
| pSfbPerWin = pFrameInfo->sfb_per_win; |
| ngroups = pFrameInfo->num_groups; |
| pGroupLen = pFrameInfo->group_len; |
| |
| pGroup = pDeinterleaved; |
| |
| for (group = ngroups; group > 0; group--) |
| { |
| pSfbWidth = pFrameInfo->sfb_width_128; |
| sfb_inc = 0; |
| pStart = pInterleaved; |
| |
| /* Perform the deinterleaving across all windows in a group */ |
| |
| for (sfb = pSfbPerWin[ngroups-group]; sfb > 0; sfb--) |
| { |
| pWin = pGroup; |
| |
| for (win = pGroupLen[ngroups-group]; win > 0; win--) |
| { |
| pDeinterleaved = pWin + sfb_inc; |
| |
| pv_memcpy( |
| pDeinterleaved, |
| pInterleaved, |
| *pSfbWidth*sizeof(*pInterleaved)); |
| |
| pInterleaved += *pSfbWidth; |
| |
| pWin += SN2; |
| |
| } /* for (win) */ |
| |
| sfb_inc += *pSfbWidth++; |
| |
| } /* for (sfb) */ |
| |
| pGroup += (pInterleaved - pStart); |
| |
| } /* for (group) */ |
| |
| } /* deinterleave */ |
