| /* ------------------------------------------------------------------ |
| * 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: huffdecode.c |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Modified from original shareware code |
| |
| Description: Modified to pass variables by reference to eliminate use |
| of global variables. |
| |
| Description: Change variable types. |
| |
| Description: (1) Modified to bring in-line with PV standards. |
| (2) Eliminated global_gain on stack, |
| getics() has to define this parameter on its stack. |
| (3) Eliminated multiple returns |
| (4) Altered return logic of getics() |
| (5) Convert Real coef -> Int32 coef |
| (6) Move BITS *pInputStream to 2nd parameter of huffdecode.c |
| and getics.c |
| (7) Pass pFrameInfo per channel, because two channels can have |
| different windows |
| |
| Description: (1) Eliminated function call to chn_config |
| (2) Eliminate widx calculation |
| (3) copy channel info from left to right when common_window |
| is enabled |
| (4) add error checking of getmask return value |
| |
| Description: Change default_position to current_program |
| |
| Description: Remove prstflag |
| |
| Description: Modify call to get_ics_info |
| |
| Description: Modified so getmask is NOT called if the status returned |
| from get_ics_info indicates an error. |
| |
| Description: |
| (1) Added include of "e_ElementId.h" |
| Previously, this function was relying on another include file |
| to include e_ElementId.h |
| |
| (2) Updated the copyright header. |
| |
| Description: Modified to include usage of the new "shared memory" structures |
| defined in s_tDec_Int_File.h and s_tDec_Int_Chan.h |
| |
| Description: |
| (1) Updated to reflect the fact that the temporary FrameInfo used by getics.c |
| was moved into the region of memory shared with fxpCoef. |
| |
| Description: |
| (1) Removed first parameter to getics. The temporary FrameInfo was |
| unnecessary. |
| |
| 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. |
| |
| Description: Relaxed tag verification. Some encoder do not match the tag |
| to the channel ID (as the standard request to differentiate |
| different channel), in our wireless work, with only mono |
| or stereo channel, this become restrictive to some encoders |
| |
| |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| |
| id_syn_ele = identification flag for channel syntactic element, Int |
| |
| pInputStream= pointer to input bitstream, BITS. |
| |
| pVars = pointer to structure that holds information for decoding, |
| tDec_Int_File |
| |
| pChVars[] = pointer to structure that holds channel information, |
| tDec_Int_Chan |
| |
| |
| Local Stores/Buffers/Pointers Needed: |
| None |
| |
| Global Stores/Buffers/Pointers Needed: |
| None |
| |
| Outputs: |
| status = 0 if success |
| non-zero otherwise |
| |
| Pointers and Buffers Modified: |
| pChVars->sect contents updated by newly decoded section information |
| of current frame |
| |
| pChVars->factors contents updated by newly decoded scalefactors |
| |
| pChVars->ch_coef contents updated by newly decoded spectral coefficients |
| |
| PChVars->tns contents updated by newly decoded TNS information |
| |
| pVars->hasmask contents updated by newly decoded Mid/Side mask |
| information |
| |
| pVars->pulseInfo contents updated by newly decoded pulse data information |
| |
| Local Stores Modified: |
| None |
| |
| Global Stores Modified: |
| None |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function offers a framework for decoding the data of the next 1024 |
| samples. It maps the channel configuration according to the id_syn_ele flag, |
| configures the channel information, and calls getics to do huffman decoding |
| The function returns 1 if there was an error |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| This function should set up the channel configuration for huffman decoding |
| |
| ------------------------------------------------------------------------------ |
| 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 p15 (single_channel_element, channel_pair_element) |
| p15 (Table 4.4.5 getmask) |
| p16 (Table 4.4.6 get_ics_info) |
| p24 (Table 4.4.24 getics) |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| tag = CALL getbits(LEN_TAG,pInputStream) |
| MODIFYING(pInputStream) |
| RETURNING(tag) |
| |
| common_window = 0; |
| |
| IF (id_syn_ele == ID_CPE) |
| THEN |
| common_window = CALL getbits(LEN_COM_WIN,pInputStream); |
| MODIFYING(pInputStream) |
| RETURNING(common_window) |
| ENDIF |
| |
| pMcInfo = &pVars->mc_info; |
| |
| IF ( (pMcInfo->ch_info[0].cpe != id_syn_ele) OR |
| (pMcInfo->ch_info[0].tag != tag) ) |
| THEN |
| status = 1; |
| ENDIF |
| |
| |
| IF (status == SUCCESS) |
| THEN |
| IF (id_syn_ele == ID_SCE) |
| THEN |
| |
| leftCh = 0; |
| RIGHT = 0; |
| pChVars[leftCh]->hasmask = 0; |
| ELSEIF (id_syn_ele == ID_CPE) |
| |
| leftCh = 0; |
| rightCh = 1; |
| |
| IF (common_window != FALSE) |
| THEN |
| |
| CALL get_ics_info( |
| audioObjectType = pVars->mc_info.audioObjectType, |
| pInputStream = pInputStream, |
| common_window = common_window, |
| pWindowSequence = &pChVars[leftCh]->wnd, |
| &pChVars[leftCh]->wnd_shape_this_bk, |
| pChVars[leftCh]->group, |
| &pChVars[leftCh]->max_sfb, |
| pVars->winmap, |
| &pChVars[leftCh]->lt_status, |
| &pChVars[rightCh]->lt_status); |
| MODIFYING(pInputStream, wnd, wnd_shape_this_bk,group, |
| max_sfb, lt_status) |
| RETURNING(status) |
| |
| IF (status == SUCCESS) |
| THEN |
| |
| pChVars[rightCh]->wnd = pChVars[leftCh]->wnd; |
| pChVars[rightCh]->wnd_shape_this_bk = |
| pChVars[leftCh]->wnd_shape_this_bk; |
| pChVars[rightCh]->max_sfb = pChVars[leftCh]->max_sfb; |
| pv_memcpy( |
| pChVars[rightCh]->group, |
| pChVars[leftCh]->group, |
| NSHORT*sizeof(pChVars[leftCh]->group[0])); |
| |
| hasmask = CALL getmask( |
| pVars->winmap[pChVars[leftCh]->wnd], |
| pInputStream, |
| pChVars[leftCh]->group, |
| pChVars[leftCh]->max_sfb, |
| pChVars[leftCh]->mask); |
| MODIFYING(pInputStream, mask) |
| RETURNING(hasmask) |
| |
| IF (hasmask == MASK_ERROR) |
| THEN |
| status = 1; |
| ENDIF |
| pChVars[leftCh]->hasmask = hasmask; |
| pChVars[rightCh]->hasmask = hasmask; |
| |
| ENDIF |
| |
| ELSE |
| |
| pChVars[leftCh]->hasmask = 0; |
| pChVars[rightCh]->hasmask = 0; |
| ENDIF(common_window) |
| |
| ENDIF(id_syn_ele) |
| |
| ENDIF (status) |
| |
| ch = leftCh; |
| |
| WHILE((ch <= rightCh) AND (status == SUCCESS)) |
| |
| status = CALL getics( |
| pInputStream, |
| common_window, |
| pVars, |
| pChVars[ch], |
| pChVars[ch]->group, |
| &pChVars[ch]->max_sfb, |
| pChVars[ch]->cb_map, |
| &pChVars[ch]->tns, |
| pVars->winmap, |
| &pVars->pulseInfo, |
| pChVars[ch]->sect); |
| MODIFYING(pInputStream,pVarsp,ChVars[ch],group, |
| max_sfb,tns,pulseInfo,sect) |
| RETURNING(status) |
| |
| ch++; |
| |
| ENDWHILE |
| |
| 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 "aac_mem_funcs.h" |
| #include "huffman.h" |
| #include "e_maskstatus.h" |
| #include "e_elementid.h" |
| #include "get_ics_info.h" |
| |
| /*---------------------------------------------------------------------------- |
| ; MACROS |
| ; Define module specific macros here |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; DEFINES |
| ; Include all pre-processor statements here. Include conditional |
| ; compile variables also. |
| ----------------------------------------------------------------------------*/ |
| #define LEFT (0) |
| #define RIGHT (1) |
| /*---------------------------------------------------------------------------- |
| ; 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 |
| ----------------------------------------------------------------------------*/ |
| Int huffdecode( |
| Int id_syn_ele, |
| BITS *pInputStream, |
| tDec_Int_File *pVars, |
| tDec_Int_Chan *pChVars[]) |
| |
| { |
| /*---------------------------------------------------------------------------- |
| ; Define all local variables |
| ----------------------------------------------------------------------------*/ |
| Int ch; |
| Int common_window; |
| Int hasmask; |
| Int status = SUCCESS; |
| Int num_channels = 0; |
| MC_Info *pMcInfo; |
| |
| per_chan_share_w_fxpCoef *pChLeftShare; /* Helper pointer */ |
| per_chan_share_w_fxpCoef *pChRightShare; /* Helper pointer */ |
| /*---------------------------------------------------------------------------- |
| ; Function body here |
| ----------------------------------------------------------------------------*/ |
| |
| get9_n_lessbits( |
| LEN_TAG, |
| pInputStream); |
| |
| /* suppose an un-supported id_syn_ele will never be passed */ |
| |
| common_window = 0; |
| |
| if (id_syn_ele == ID_CPE) |
| { |
| common_window = |
| get1bits(pInputStream); |
| } |
| |
| pMcInfo = &pVars->mc_info; |
| |
| /* |
| * check if provided info (num of channels) on audio config, |
| * matches read bitstream data, if not, allow update only once. |
| * In almost all cases it should match. |
| */ |
| if ((pMcInfo->ch_info[0].cpe != id_syn_ele)) |
| { |
| if (pVars->mc_info.implicit_channeling) /* check done only once */ |
| { |
| pMcInfo->ch_info[0].cpe = id_syn_ele & 1; /* collect info from bitstream |
| * implicit_channeling flag is locked |
| * after 1st frame, to avoid toggling |
| * parameter in the middle of the clip |
| */ |
| pMcInfo->nch = (id_syn_ele & 1) + 1; /* update number of channels */ |
| } |
| else |
| { |
| status = 1; /* ERROR break if syntax error persist */ |
| } |
| } |
| |
| if (status == SUCCESS) |
| { |
| if (id_syn_ele == ID_SCE) |
| { |
| |
| num_channels = 1; |
| pVars->hasmask = 0; |
| } |
| else if (id_syn_ele == ID_CPE) |
| { |
| pChLeftShare = pChVars[LEFT]->pShareWfxpCoef; |
| pChRightShare = pChVars[RIGHT]->pShareWfxpCoef; |
| num_channels = 2; |
| |
| if (common_window != FALSE) |
| { |
| |
| status = get_ics_info( |
| (tMP4AudioObjectType) pVars->mc_info.audioObjectType, |
| pInputStream, |
| (Bool)common_window, |
| (WINDOW_SEQUENCE *) & pChVars[LEFT]->wnd, |
| (WINDOW_SHAPE *) & pChVars[LEFT]->wnd_shape_this_bk, |
| pChLeftShare->group, |
| (Int *) & pChLeftShare->max_sfb, |
| pVars->winmap, |
| (LT_PRED_STATUS *) & pChLeftShare->lt_status, |
| (LT_PRED_STATUS *) & pChRightShare->lt_status); |
| |
| if (status == SUCCESS) |
| { |
| /* copy left channel info to right channel */ |
| pChVars[RIGHT]->wnd = pChVars[LEFT]->wnd; |
| pChVars[RIGHT]->wnd_shape_this_bk = |
| pChVars[LEFT]->wnd_shape_this_bk; |
| pChRightShare->max_sfb = pChLeftShare->max_sfb; |
| pv_memcpy( |
| pChRightShare->group, |
| pChLeftShare->group, |
| NSHORT*sizeof(pChLeftShare->group[0])); |
| |
| hasmask = getmask( |
| pVars->winmap[pChVars[LEFT]->wnd], |
| pInputStream, |
| pChLeftShare->group, |
| pChLeftShare->max_sfb, |
| pVars->mask); |
| |
| if (hasmask == MASK_ERROR) |
| { |
| status = 1; /* ERROR code */ |
| } |
| pVars->hasmask = hasmask; |
| |
| } /* if (status == 0) */ |
| } |
| else |
| { |
| pVars->hasmask = 0; |
| } /* if (common_window) */ |
| |
| } /* if (id_syn_ele) */ |
| |
| } /* if (status) */ |
| |
| ch = 0; |
| while ((ch < num_channels) && (status == SUCCESS)) |
| { |
| pChLeftShare = pChVars[ch]->pShareWfxpCoef; |
| |
| status = getics( |
| pInputStream, |
| common_window, |
| pVars, |
| pChVars[ch], |
| pChLeftShare->group, |
| &pChLeftShare->max_sfb, |
| pChLeftShare->cb_map, |
| &pChLeftShare->tns, |
| pVars->winmap, |
| &pVars->share.a.pulseInfo, |
| pVars->share.a.sect); |
| |
| ch++; |
| |
| } /* while (ch) */ |
| |
| /*---------------------------------------------------------------------------- |
| ; Return status |
| ----------------------------------------------------------------------------*/ |
| |
| return status; |
| |
| } /* huffdecode */ |
| |
