msis.c
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上传日期:2013-07-19
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- /* ***** BEGIN LICENSE BLOCK *****
- * Version: RCSL 1.0/RPSL 1.0
- *
- * Portions Copyright (c) 1995-2002 RealNetworks, Inc. All Rights Reserved.
- *
- * The contents of this file, and the files included with this file, are
- * subject to the current version of the RealNetworks Public Source License
- * Version 1.0 (the "RPSL") available at
- * http://www.helixcommunity.org/content/rpsl unless you have licensed
- * the file under the RealNetworks Community Source License Version 1.0
- * (the "RCSL") available at http://www.helixcommunity.org/content/rcsl,
- * in which case the RCSL will apply. You may also obtain the license terms
- * directly from RealNetworks. You may not use this file except in
- * compliance with the RPSL or, if you have a valid RCSL with RealNetworks
- * applicable to this file, the RCSL. Please see the applicable RPSL or
- * RCSL for the rights, obligations and limitations governing use of the
- * contents of the file.
- *
- * This file is part of the Helix DNA Technology. RealNetworks is the
- * developer of the Original Code and owns the copyrights in the portions
- * it created.
- *
- * This file, and the files included with this file, is distributed and made
- * available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- *
- * Technology Compatibility Kit Test Suite(s) Location:
- * http://www.helixcommunity.org/content/tck
- *
- * Contributor(s):
- *
- * ***** END LICENSE BLOCK ***** */
- #include "hlxclib/string.h"
- #include "statname.h"
- /**** msis.c ***************************************************
- Layer III
- antialias, ms and is stereo precessing
- **** is_process assumes never switch
- from short to long in is region *****
-
- is_process does ms or stereo in "forbidded sf regions"
- //ms_mode = 0
- lr[0][i][0] = 1.0f;
- lr[0][i][1] = 0.0f;
- // ms_mode = 1, in is bands is routine does ms processing
- lr[1][i][0] = 1.0f;
- lr[1][i][1] = 1.0f;
- ******************************************************************/
- #include "l3.h"
- #ifdef __cplusplus
- extern "C" {
- #endif
- void antialias(float x[], int n);
- void ms_process(float x[][1152], int n);
- void is_process_MPEG1(float x[][1152],
- SCALEFACT *sf,
- CB_INFO cb_info[2],
- int nsamp, int ms_mode, int nBand[2][22], int sfBandIndex[2][22]);
- void is_process_MPEG2(float x[][1152],
- SCALEFACT *sf,
- CB_INFO cb_info[2],
- IS_SF_INFO *is_sf_info,
- int nsamp, int ms_mode, int nBand[2][22], int sfBandIndex[2][22]);
- #ifdef __cplusplus
- }
- #endif
- typedef float ARRAY2[2];
- typedef float ARRAY8_2[8][2];
- typedef float ARRAY2_64_2[2][64][2];
- typedef float ARRAY64_2[64][2];
- extern const float lr[2][8][2];
- extern const float lr2[2][2][64][2];
- /* antialias
- for(i=0;i<8;i++) {
- csa[i][0] = (float)(1.0/sqrt(1.0 + Ci[i]*Ci[i]));
- csa[i][1] = (float)(Ci[i]/sqrt(1.0 + Ci[i]*Ci[i]));
- }
- */
- static const float csa[8][2] = {
- {8.5749292374e-001f, -5.1449579000e-001f}, {8.8174200058e-001f, -4.7173199058e-001f},
- {9.4962865114e-001f, -3.1337746978e-001f}, {9.8331457376e-001f, -1.8191319704e-001f},
- {9.9551779032e-001f, -9.4574190676e-002f}, {9.9916058779e-001f, -4.0965583175e-002f},
- {9.9989920855e-001f, -1.4198568650e-002f}, {9.9999314547e-001f, -3.6999746226e-003f},
- };
- /*===============================================================*/
- void antialias(float x[], int n)
- {
- int i, k;
- float a, b;
- for(k=0;k<n;k++) {
- for(i=0;i<8;i++) {
- a = x[17-i];
- b = x[18+i];
- x[17-i] = a*csa[i][0] - b*csa[i][1];
- x[18+i] = b*csa[i][0] + a*csa[i][1];
- }
- x+=18;
- }
- }
- /*===============================================================*/
- void ms_process(float x[][1152], int n) /* sum-difference stereo */
- {
- int i;
- float xl, xr;
- /*-- note: sqrt(2) done scaling by dequant ---*/
- for(i=0;i<n;i++) {
- xl = x[0][i] + x[1][i];
- xr = x[0][i] - x[1][i];
- x[0][i] = xl;
- x[1][i] = xr;
- }
- return;
- }
- /*===============================================================*/
- void is_process_MPEG1(float x[][1152], /* intensity stereo */
- SCALEFACT *sf,
- CB_INFO cb_info[2], /* [ch] */
- int nsamp, int ms_mode, int nBand[2][22], int sfBandIndex[2][22])
- {
- int i, j, n, cb, w;
- float fl, fr;
- int m;
- int isf;
- float fls[3], frs[3];
- int cb0;
- cb0 = cb_info[1].cbmax; /* start at end of right */
- i = sfBandIndex[cb_info[1].cbtype][cb0];
- cb0++;
- m = nsamp - i; /* process to len of left */
- if( cb_info[1].cbtype ) goto short_blocks;
- /*------------------------*/
- /* long_blocks: */
- for(cb=cb0;cb<21;cb++) {
- isf = sf->l[cb];
- n = nBand[0][cb];
- fl = lr[ms_mode][isf][0];
- fr = lr[ms_mode][isf][1];
- for(j=0;j<n;j++,i++) {
- if( --m < 0 ) goto exit;
- x[1][i] = fr*x[0][i];
- x[0][i] = fl*x[0][i];
- }
- }
- return;
- /*------------------------*/
- short_blocks:
- for(cb=cb0;cb<12;cb++) {
- for(w=0;w<3;w++) {
- isf = sf->s[w][cb];
- fls[w] = lr[ms_mode][isf][0];
- frs[w] = lr[ms_mode][isf][1];
- }
- n = nBand[1][cb];
- for(j=0;j<n;j++) {
- m-=3;
- if( m < 0 ) goto exit;
- x[1][i] = frs[0]*x[0][i];
- x[0][i] = fls[0]*x[0][i];
- x[1][1+i] = frs[1]*x[0][1+i];
- x[0][1+i] = fls[1]*x[0][1+i];
- x[1][2+i] = frs[2]*x[0][2+i];
- x[0][2+i] = fls[2]*x[0][2+i];
- i+=3;
- }
- }
- exit:
- return;
- }
- /*===============================================================*/
- void is_process_MPEG2(float x[][1152], /* intensity stereo */
- SCALEFACT *sf,
- CB_INFO cb_info[2], /* [ch] */
- IS_SF_INFO *is_sf_info,
- int nsamp, int ms_mode, int nBand[2][22], int sfBandIndex[2][22])
- {
- int i, j, k, n, cb, w;
- float fl, fr;
- int m;
- int isf;
- int il[21];
- int tmp;
- int r;
- const ARRAY2 *lr;
- int cb0, cb1;
- memset((void*)il, 0, sizeof(il));
- lr = lr2[is_sf_info->intensity_scale][ms_mode];
- if( cb_info[1].cbtype ) goto short_blocks;
- /*------------------------*/
- /* long_blocks: */
- cb0 = cb_info[1].cbmax; /* start at end of right */
- i = sfBandIndex[0][cb0];
- m = nsamp - i; /* process to len of left */
- /* gen sf info */
- for(k=r=0;r<3;r++) {
- tmp = (1 << is_sf_info->slen[r]) -1;
- for(j=0;j<is_sf_info->nr[r];j++, k++) il[k] = tmp;
- }
- for(cb=cb0+1; cb<21;cb++) {
- isf = il[cb] + sf->l[cb];
- fl = lr[isf][0];
- fr = lr[isf][1];
- n = nBand[0][cb];
- for(j=0;j<n;j++,i++) {
- if( --m < 0 ) goto exit;
- x[1][i] = fr*x[0][i];
- x[0][i] = fl*x[0][i];
- }
- }
- return;
- /*------------------------*/
- short_blocks:
- for(k=r=0;r<3;r++) {
- tmp = (1 << is_sf_info->slen[r]) -1;
- for(j=0;j<is_sf_info->nr[r];j++, k++) il[k] = tmp;
- }
- for(w=0;w<3;w++) {
- cb0 = cb_info[1].cbmax_s[w]; /* start at end of right */
- i = sfBandIndex[1][cb0] + w;
- cb1 = cb_info[0].cbmax_s[w]; /* process to end of left */
- for(cb=cb0+1;cb<=cb1;cb++) {
- isf = il[cb] + sf->s[w][cb];
- fl = lr[isf][0];
- fr = lr[isf][1];
- n = nBand[1][cb];
- for(j=0;j<n;j++) {
- x[1][i] = fr*x[0][i];
- x[0][i] = fl*x[0][i];
- i+=3;
- }
- }
- }
- exit:
- return;
- }
- /*===============================================================*/