media/libstagefright/codecs/aacdec/calc_gsfb_table.cpp - third_party/android/platform/frameworks/av - Git at Google

 /* ------------------------------------------------------------------
  * 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/calc_gsfb_table.c

 ------------------------------------------------------------------------------
  REVISION HISTORY

  Description:  Modified from original shareware code

  Description: (1) Modified to bring in-line with PV standards
               (2) Removed if(pFrameInfo->islong), only short windows will
                   call this routine from getics.c

  Description: Modified per review comments

  Who:                       Date:
  Description:

 ------------------------------------------------------------------------------
  INPUT AND OUTPUT DEFINITIONS

  Inputs:
     pFrameInfo  = pointer to structure that holds information for current
                   frame. Data type FrameInfo

     group[]     = array that contains the grouping information of short
                   windows (stop index of windows in each group).
                   Data type Int

  Local Stores/Buffers/Pointers Needed:
     None

  Global Stores/Buffers/Pointers Needed:
     None

  Outputs:
     None

  Pointers and Buffers Modified:
     pFrameInfo -> frame_sfb_top   contains the cumulative bandwidth of
                                     scalefactor bands in each group

  Local Stores Modified:
     None

  Global Stores Modified:
     None

 ------------------------------------------------------------------------------
  FUNCTION DESCRIPTION

  This function is only invoked when short windows are present. It calculates
  the number of groups in one frame, and the scalefactor bandwidth of each
  scalefactor band in each group.
  All windows within one group share the same scalefactors and are interleaved
  on a scalefactor band basis. Within each group, the actual length of one
  scalefactor band equals to the number of windows times the number of
  coefficients in a regular scalefactor band.

 ------------------------------------------------------------------------------
  REQUIREMENTS

  This function shall replace the contents of pFrameInfo->frame_sfb_top
  with the cumulative bandwidth of each scalefactor band in each group

 ------------------------------------------------------------------------------
  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       p54.    4.5.2.3.2   decoding process

 ------------------------------------------------------------------------------
  PSEUDO-CODE

     offset      = 0;
     group_idx   = 0;

     DO
         pFrameInfo->group_len[group_idx] = group[group_idx] - offset;
         offset = group[group_idx];
         group_idx++;

     WHILE (offset < NUM_SHORT_WINDOWS);


     pFrameInfo->num_groups = group_idx;

     pFrameSfbTop = pFrameInfo->frame_sfb_top;
     offset = 0;

     FOR (group_idx = 0; group_idx < pFrameInfo->num_groups; group_idx++)

         len = pFrameInfo->group_len[group_idx];

         FOR (sfb = 0; sfb < pFrameInfo->sfb_per_win[group_idx]; sfb++)

             offset += pFrameInfo->sfb_width_128[sfb] * len;
             *pFrameSfbTop++ = offset;

         ENDFOR

     ENDFOR

 ------------------------------------------------------------------------------
  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  calc_gsfb_table(
     FrameInfo   *pFrameInfo,
     Int         group[])
 {

     Int      group_idx;
     Int      offset;
     Int     *pFrameSfbTop;
     Int     *pSfbWidth128;
     Int      sfb;
     Int      nsfb;
     Int      len;
     Int      ngroups;

     /* clear out the default values set by infoinit */
     /* */
     pv_memset(pFrameInfo->frame_sfb_top,
               0,
               MAXBANDS*sizeof(pFrameInfo->frame_sfb_top[0]));
     /* */
     /* first calculate the group length*/
     offset      = 0;
     ngroups     = 0;
     do
     {
         pFrameInfo->group_len[ngroups] = group[ngroups] - offset;
         offset = group[ngroups];
         ngroups++;

     }
     while (offset < NUM_SHORT_WINDOWS);


     /* calculate the cumulative scalefactor bandwidth for one frame */
     pFrameInfo->num_groups = ngroups;

     pFrameSfbTop = pFrameInfo->frame_sfb_top;
     offset = 0;


     for (group_idx = 0; group_idx < ngroups; group_idx++)
     {
         len  = pFrameInfo->group_len[  group_idx];
         nsfb = pFrameInfo->sfb_per_win[group_idx];

         pSfbWidth128 = pFrameInfo->sfb_width_128;

         for (sfb = nsfb; sfb > 0; sfb--)
         {
             offset += *pSfbWidth128++ * len;
             *pFrameSfbTop++ = offset;
         }
     }


 } /* calc_gsfb_table */
	/* ------------------------------------------------------------------
	* 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/calc_gsfb_table.c

	------------------------------------------------------------------------------
	REVISION HISTORY

	Description: Modified from original shareware code

	Description: (1) Modified to bring in-line with PV standards
	(2) Removed if(pFrameInfo->islong), only short windows will
	call this routine from getics.c

	Description: Modified per review comments

	Who: Date:
	Description:

	------------------------------------------------------------------------------
	INPUT AND OUTPUT DEFINITIONS

	Inputs:
	pFrameInfo = pointer to structure that holds information for current
	frame. Data type FrameInfo

	group[] = array that contains the grouping information of short
	windows (stop index of windows in each group).
	Data type Int

	Local Stores/Buffers/Pointers Needed:
	None

	Global Stores/Buffers/Pointers Needed:
	None

	Outputs:
	None

	Pointers and Buffers Modified:
	pFrameInfo -> frame_sfb_top contains the cumulative bandwidth of
	scalefactor bands in each group

	Local Stores Modified:
	None

	Global Stores Modified:
	None

	------------------------------------------------------------------------------
	FUNCTION DESCRIPTION

	This function is only invoked when short windows are present. It calculates
	the number of groups in one frame, and the scalefactor bandwidth of each
	scalefactor band in each group.
	All windows within one group share the same scalefactors and are interleaved
	on a scalefactor band basis. Within each group, the actual length of one
	scalefactor band equals to the number of windows times the number of
	coefficients in a regular scalefactor band.

	------------------------------------------------------------------------------
	REQUIREMENTS

	This function shall replace the contents of pFrameInfo->frame_sfb_top
	with the cumulative bandwidth of each scalefactor band in each group

	------------------------------------------------------------------------------
	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 p54. 4.5.2.3.2 decoding process

	------------------------------------------------------------------------------
	PSEUDO-CODE

	offset = 0;
	group_idx = 0;

	DO
	pFrameInfo->group_len[group_idx] = group[group_idx] - offset;
	offset = group[group_idx];
	group_idx++;

	WHILE (offset < NUM_SHORT_WINDOWS);


	pFrameInfo->num_groups = group_idx;

	pFrameSfbTop = pFrameInfo->frame_sfb_top;
	offset = 0;

	FOR (group_idx = 0; group_idx < pFrameInfo->num_groups; group_idx++)

	len = pFrameInfo->group_len[group_idx];

	FOR (sfb = 0; sfb < pFrameInfo->sfb_per_win[group_idx]; sfb++)

	offset += pFrameInfo->sfb_width_128[sfb] * len;
	*pFrameSfbTop++ = offset;

	ENDFOR

	ENDFOR

	------------------------------------------------------------------------------
	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 calc_gsfb_table(
	FrameInfo *pFrameInfo,
	Int group[])
	{

	Int group_idx;
	Int offset;
	Int *pFrameSfbTop;
	Int *pSfbWidth128;
	Int sfb;
	Int nsfb;
	Int len;
	Int ngroups;

	/* clear out the default values set by infoinit */
	/* */
	pv_memset(pFrameInfo->frame_sfb_top,
	0,
	MAXBANDS*sizeof(pFrameInfo->frame_sfb_top[0]));
	/* */
	/* first calculate the group length*/
	offset = 0;
	ngroups = 0;
	do
	{
	pFrameInfo->group_len[ngroups] = group[ngroups] - offset;
	offset = group[ngroups];
	ngroups++;

	}
	while (offset < NUM_SHORT_WINDOWS);


	/* calculate the cumulative scalefactor bandwidth for one frame */
	pFrameInfo->num_groups = ngroups;

	pFrameSfbTop = pFrameInfo->frame_sfb_top;
	offset = 0;


	for (group_idx = 0; group_idx < ngroups; group_idx++)
	{
	len = pFrameInfo->group_len[ group_idx];
	nsfb = pFrameInfo->sfb_per_win[group_idx];

	pSfbWidth128 = pFrameInfo->sfb_width_128;

	for (sfb = nsfb; sfb > 0; sfb--)
	{
	offset += pSfbWidth128++ len;
	*pFrameSfbTop++ = offset;
	}
	}


	} /* calc_gsfb_table */