ref: 02ce1b0c415872da32c880c981ed3191f4233301
dir: /ms.c/
/* * MS stereo coding * * Copyright (c) 1999 M. Bakker * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; see the file COPYING. If not, write to * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ /************************************************************************** Version Control Information Method: CVS Identifiers: $Revision: 1.14 $ $Date: 2000/10/05 08:39:02 $ (check in) $Author: menno $ *************************************************************************/ #include "psych.h" #include "ms.h" void MSPreprocess(double p_ratio_long[][MAX_SCFAC_BANDS], double p_ratio_short[][MAX_SCFAC_BANDS], CH_PSYCH_OUTPUT_LONG p_chpo_long[], CH_PSYCH_OUTPUT_SHORT p_chpo_short[][MAX_SHORT_WINDOWS], Ch_Info *channelInfo, /* Pointer to Ch_Info */ enum WINDOW_TYPE block_type[MAX_TIME_CHANNELS], /* Block type */ AACQuantInfo* quantInfo, /* Quant info */ int use_ms, int numberOfChannels ) { int chanNum; int sfbNum; int used = 0, notused = 0; int realyused = 0; /* Look for channel_pair_elements */ for (chanNum=0;chanNum<numberOfChannels;chanNum++) { if (channelInfo[chanNum].present) { if ((channelInfo[chanNum].cpe)&&(channelInfo[chanNum].ch_is_left)) { int leftChan=chanNum; int rightChan=channelInfo[chanNum].paired_ch; channelInfo[leftChan].ms_info.is_present=0; channelInfo[leftChan].common_window = 0; /* Perform MS if block_types are the same */ if ((block_type[leftChan]==block_type[rightChan])&&(use_ms==0)) { int numGroups; int groupIndex = 0; int maxSfb, isBand; int g,b,j; int use_ms_short; MS_Info *msInfo; numGroups = quantInfo[leftChan].num_window_groups; maxSfb = quantInfo[leftChan].max_sfb; /* Determine which bands should be enabled */ msInfo = &(channelInfo[leftChan].ms_info); isBand = maxSfb; for (g=0;g<numGroups;g++) { for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { use_ms_short = 1; b = g*maxSfb+sfbNum; if (block_type[leftChan] == ONLY_SHORT_WINDOW) { for (j = groupIndex; j < quantInfo[leftChan].window_group_length[g]+groupIndex; j++) { use_ms_short = min(use_ms_short, p_chpo_short[rightChan][j].use_ms[sfbNum]); } if (sfbNum < isBand) { msInfo->ms_used[b] = use_ms_short; } else { msInfo->ms_used[b] = 0; use_ms_short = 0; } if (msInfo->ms_used[b]) { realyused = 1; used++; for (j = groupIndex; j < quantInfo[leftChan].window_group_length[g]+groupIndex; j++) { p_ratio_short[leftChan][(g*maxSfb)+sfbNum] = p_chpo_short[leftChan][j].p_ratio[sfbNum]; p_ratio_short[rightChan][(g*maxSfb)+sfbNum] = p_chpo_short[rightChan][j].p_ratio[sfbNum]; p_chpo_short[rightChan][j].use_ms[sfbNum] = use_ms_short; } } else { notused++; for (j = groupIndex; j < quantInfo[leftChan].window_group_length[g]+groupIndex; j++) { p_ratio_short[leftChan][(g*maxSfb)+sfbNum] = p_chpo_short[leftChan][j].p_ratio[sfbNum]; p_ratio_short[rightChan][(g*maxSfb)+sfbNum] = p_chpo_short[rightChan][j].p_ratio[sfbNum]; p_chpo_short[rightChan][j].use_ms[sfbNum] = use_ms_short; } } } else { if (sfbNum < isBand) { msInfo->ms_used[b] = p_chpo_long[rightChan].use_ms[sfbNum]; } else { msInfo->ms_used[b] = 0; p_chpo_long[rightChan].use_ms[sfbNum] = 0; } if (msInfo->ms_used[b]) { realyused = 1; used++; p_ratio_long[leftChan][sfbNum] = p_chpo_long[leftChan].p_ratio[sfbNum]; p_ratio_long[rightChan][sfbNum] = p_chpo_long[rightChan].p_ratio[sfbNum]; } else { notused++; p_ratio_long[leftChan][sfbNum] = p_chpo_long[leftChan].p_ratio[sfbNum]; p_ratio_long[rightChan][sfbNum] = p_chpo_long[rightChan].p_ratio[sfbNum]; } } } groupIndex+=quantInfo[leftChan].window_group_length[g]; } if (realyused) { channelInfo[leftChan].common_window = 1; /* Use common window */ channelInfo[leftChan].ms_info.is_present=1; channelInfo[rightChan].common_window = 1; /* Use common window */ channelInfo[rightChan].ms_info.is_present=1; } } else if ((block_type[leftChan]==block_type[rightChan])&&(use_ms == 1)) { int chan; int numGroups; int groupIndex; int maxSfb; int g,b,j; MS_Info *msInfo; channelInfo[leftChan].ms_info.is_present = 1; channelInfo[leftChan].common_window = 1; channelInfo[rightChan].ms_info.is_present = 1; channelInfo[rightChan].common_window = 1; for (chan = 0; chan < 2; chan++) { int chan2; if (chan == 0) chan2 = leftChan; else chan2 = rightChan; maxSfb = quantInfo[chan].max_sfb; /* Determine which bands should be enabled */ msInfo = &(channelInfo[leftChan].ms_info); numGroups = quantInfo[chan2].num_window_groups; for (g=0;g<numGroups;g++) { for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { b = g*maxSfb+sfbNum; groupIndex = 0; if (block_type[chan2] == ONLY_SHORT_WINDOW) { msInfo->ms_used[b] = 1; for (j = groupIndex; j < quantInfo[chan2].window_group_length[g]+groupIndex; j++) { p_ratio_short[chan2][(g*maxSfb)+sfbNum] = p_chpo_short[chan2][j].p_ratio[sfbNum]; p_chpo_short[rightChan][j].use_ms[sfbNum] = 1; } } else { msInfo->ms_used[b] = 1; p_ratio_long[chan2][sfbNum] = p_chpo_long[chan2].p_ratio[sfbNum]; p_chpo_long[rightChan].use_ms[sfbNum] = 1; } } // groupIndex+=quantInfo[chan2].window_group_length[g]; } } } else { int chan; int numGroups; int groupIndex; int maxSfb; int g,b,j; MS_Info *msInfo; for (chan = 0; chan < 2; chan++) { int chan2; if (chan == 0) chan2 = leftChan; else chan2 = rightChan; maxSfb = quantInfo[chan].max_sfb; /* Determine which bands should be enabled */ msInfo = &(channelInfo[leftChan].ms_info); numGroups = quantInfo[chan2].num_window_groups; for (g=0;g<numGroups;g++) { for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { b = g*maxSfb+sfbNum; groupIndex = 0; if (block_type[chan2] == ONLY_SHORT_WINDOW) { msInfo->ms_used[b] = 0; for (j = groupIndex; j < quantInfo[chan].window_group_length[g]+groupIndex; j++) { p_ratio_short[chan2][(g*maxSfb)+sfbNum] = p_chpo_short[chan2][j].p_ratio[sfbNum]; p_chpo_short[rightChan][j].use_ms[sfbNum] = 0; } } else { msInfo->ms_used[b] = 0; p_ratio_long[chan2][sfbNum] = p_chpo_long[chan2].p_ratio[sfbNum]; p_chpo_long[rightChan].use_ms[sfbNum] = 0; } } // groupIndex+=quantInfo[chan2].window_group_length[g]; } } } } } } } void MSEnergy(double *spectral_line_vector[MAX_TIME_CHANNELS], double energy[MAX_TIME_CHANNELS][MAX_SCFAC_BANDS], CH_PSYCH_OUTPUT_LONG p_chpo_long[], CH_PSYCH_OUTPUT_SHORT p_chpo_short[][MAX_SHORT_WINDOWS], int sfb_width_table[MAX_TIME_CHANNELS][MAX_SCFAC_BANDS], Ch_Info *channelInfo, /* Pointer to Ch_Info */ enum WINDOW_TYPE block_type[MAX_TIME_CHANNELS], /* Block type */ AACQuantInfo* quantInfo, /* Quant info */ int use_ms, int numberOfChannels ) { int chanNum, numWindows, bandNumber; int windowLength, w, j; int *p_use_ms; double dtmp; for (chanNum=0;chanNum<numberOfChannels;chanNum++) { if (channelInfo[chanNum].present) { if ((channelInfo[chanNum].cpe)&&(channelInfo[chanNum].ch_is_left)) { int leftChan = chanNum; int rightChan = channelInfo[chanNum].paired_ch; /* Compute energy in each scalefactor band of each window */ numWindows = (block_type[chanNum]==ONLY_SHORT_WINDOW) ? 8 : 1; windowLength = 1024/8; bandNumber=0; for (w=0;w<numWindows;w++) { int offset=0; int sfb; if (block_type[chanNum] == ONLY_SHORT_WINDOW) { p_use_ms = p_chpo_short[rightChan][w].use_ms; } else { p_use_ms = p_chpo_long[rightChan].use_ms; } j = w*windowLength; /* Only compute energy up to max_sfb */ for(sfb=0; sfb< quantInfo[chanNum].max_sfb; sfb++ ) { /* calculate scale factor band energy */ int width,i; energy[leftChan][bandNumber] = 0.0; energy[rightChan][bandNumber] = 0.0; width=sfb_width_table[chanNum][sfb]; for(i=offset; i<(offset+width); i++ ) { if ((p_use_ms[sfb]||(use_ms==1))&&(use_ms!=-1)) { dtmp = (spectral_line_vector[leftChan][j]+spectral_line_vector[rightChan][j])*0.5; energy[leftChan][bandNumber] += dtmp*dtmp; dtmp = (spectral_line_vector[leftChan][j]-spectral_line_vector[rightChan][j])*0.5; energy[rightChan][bandNumber] += dtmp*dtmp; } else { dtmp = spectral_line_vector[leftChan][j]; energy[leftChan][bandNumber] += dtmp*dtmp; dtmp = spectral_line_vector[rightChan][j]; energy[rightChan][bandNumber] += dtmp*dtmp; } j++; } energy[leftChan][bandNumber] = energy[leftChan][bandNumber] / width; energy[rightChan][bandNumber] = energy[rightChan][bandNumber] / width; bandNumber++; offset+=width; } } } else { /* SCE or LFE */ /* Compute energy in each scalefactor band of each window */ numWindows = (block_type[chanNum]==ONLY_SHORT_WINDOW) ? 8 : 1; windowLength = 1024/8; bandNumber=0; for (w=0;w<numWindows;w++) { int offset=0; int sfb; j = w*windowLength; /* Only compute energy up to max_sfb */ for(sfb = 0; sfb < quantInfo[chanNum].max_sfb; sfb++ ) { /* calculate scale factor band energy */ int width, i; energy[chanNum][bandNumber] = 0.0; width=sfb_width_table[chanNum][sfb]; for(i=offset; i<(offset+width); i++ ) { dtmp = spectral_line_vector[chanNum][j]; energy[chanNum][bandNumber] += dtmp*dtmp; j++; } energy[chanNum][bandNumber] = energy[chanNum][bandNumber] / width; bandNumber++; offset+=width; } } } } } /* for (chanNum... */ } /* Perform MS encoding. Spectrum is non-interleaved. */ /* This would be a lot simpler on interleaved spectral data */ void MSEncode(double *spectrum[MAX_TIME_CHANNELS], /* array of pointers to spectral data */ Ch_Info *channelInfo, /* Pointer to Ch_Info */ int sfb_offset_table[][MAX_SCFAC_BANDS+1], enum WINDOW_TYPE block_type[MAX_TIME_CHANNELS], /* Block type */ AACQuantInfo* quantInfo, /* Quant info */ int numberOfChannels) /* Number of channels */ { int chanNum; int sfbNum; int lineNum; double sum,diff; /* Look for channel_pair_elements */ for (chanNum=0;chanNum<numberOfChannels;chanNum++) { if (channelInfo[chanNum].present) { if ((channelInfo[chanNum].cpe)&&(channelInfo[chanNum].ch_is_left)) { int leftChan=chanNum; int rightChan=channelInfo[chanNum].paired_ch; channelInfo[leftChan].ms_info.is_present=0; /* Perform MS if block_types are the same */ if (block_type[leftChan]==block_type[rightChan]) { int numGroups; int maxSfb; int g,b,w,line_offset; int startWindow,stopWindow; MS_Info *msInfo; channelInfo[leftChan].common_window = 1; /* Use common window */ channelInfo[leftChan].ms_info.is_present=1; channelInfo[rightChan].common_window = 1; /* Use common window */ channelInfo[rightChan].ms_info.is_present=1; numGroups = quantInfo[leftChan].num_window_groups; maxSfb = quantInfo[leftChan].max_sfb; /* Determine which bands should be enabled */ /* Right now, simply enable bands which do not use intensity stereo */ msInfo = &(channelInfo[leftChan].ms_info); for (g=0;g<numGroups;g++) { for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { b = g*maxSfb+sfbNum; msInfo->ms_used[b] = 1; } } /* Perform sum and differencing on bands in which ms_used flag */ /* has been set. */ startWindow = 0; for (g=0;g<numGroups;g++) { int numWindows = quantInfo[leftChan].window_group_length[g]; stopWindow = startWindow + numWindows; for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { /* Enable MS mask */ if (msInfo->ms_used[g*maxSfb+sfbNum]) { for (w=startWindow;w<stopWindow;w++) { for (lineNum=sfb_offset_table[leftChan][sfbNum]; lineNum<sfb_offset_table[leftChan][sfbNum+1]; lineNum++) { line_offset = w*BLOCK_LEN_SHORT; sum=spectrum[leftChan][line_offset+lineNum]+spectrum[rightChan][line_offset+lineNum]; diff=spectrum[leftChan][line_offset+lineNum]-spectrum[rightChan][line_offset+lineNum]; spectrum[leftChan][line_offset+lineNum] = 0.5 * sum; spectrum[rightChan][line_offset+lineNum] = 0.5 * diff; } /* for (lineNum... */ } /* for (w=... */ } } /* for (sfbNum... */ startWindow = stopWindow; } /* for (g... */ } /* if (block_type... */ } } /* if (channelInfo[chanNum].present */ } /* for (chanNum... */ } /* Perform MS encoding. Spectrum is non-interleaved. */ /* This would be a lot simpler on interleaved spectral data */ void MSEncodeSwitch(double *spectrum[MAX_TIME_CHANNELS], /* array of pointers to spectral data */ Ch_Info *channelInfo, /* Pointer to Ch_Info */ int sfb_offset_table[][MAX_SCFAC_BANDS+1], // enum WINDOW_TYPE block_type[MAX_TIME_CHANNELS], /* Block type */ AACQuantInfo* quantInfo, /* Quant info */ int numberOfChannels /* Number of channels */ ) { int chanNum; int sfbNum; int lineNum; double sum,diff; /* Look for channel_pair_elements */ for (chanNum=0;chanNum<numberOfChannels;chanNum++) { if (channelInfo[0].ms_info.is_present) { if ((channelInfo[chanNum].cpe)&&(channelInfo[chanNum].ch_is_left)) { int leftChan=chanNum; int rightChan=channelInfo[chanNum].paired_ch; int numGroups; int maxSfb; int g,/*b,*/w,line_offset; int startWindow,stopWindow; MS_Info *msInfo; channelInfo[leftChan].common_window = 1; /* Use common window */ channelInfo[leftChan].ms_info.is_present=1; channelInfo[rightChan].common_window = 1; /* Use common window */ channelInfo[rightChan].ms_info.is_present=1; numGroups = quantInfo[leftChan].num_window_groups; maxSfb = quantInfo[leftChan].max_sfb; /* Determine which bands should be enabled */ /* Right now, simply enable bands which do not use intensity stereo */ msInfo = &(channelInfo[leftChan].ms_info); #if 0 for (g=0;g<numGroups;g++) { for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { b = g*maxSfb+sfbNum; msInfo->ms_used[b] = msInfo->ms_used[b]; } } #endif /* Perform sum and differencing on bands in which ms_used flag */ /* has been set. */ startWindow = 0; for (g=0;g<numGroups;g++) { int numWindows = quantInfo[leftChan].window_group_length[g]; stopWindow = startWindow + numWindows; for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { /* Enable MS mask */ if (msInfo->ms_used[g*maxSfb+sfbNum]) { for (w=startWindow;w<stopWindow;w++) { for (lineNum=sfb_offset_table[leftChan][sfbNum];lineNum<sfb_offset_table[leftChan][sfbNum+1];lineNum++) { line_offset = w*BLOCK_LEN_SHORT; sum=spectrum[leftChan][line_offset+lineNum]+spectrum[rightChan][line_offset+lineNum]; diff=spectrum[leftChan][line_offset+lineNum]-spectrum[rightChan][line_offset+lineNum]; spectrum[leftChan][line_offset+lineNum] = 0.5 * sum; spectrum[rightChan][line_offset+lineNum] = 0.5 * diff; } /* for (lineNum... */ } /* for (w=... */ } } /* for (sfbNum... */ startWindow = stopWindow; } /* for (g... */ } } } /* for (chanNum... */ } void MSReconstruct(double *spectrum[MAX_TIME_CHANNELS], /* array of pointers to spectral data */ Ch_Info *channelInfo, /* Pointer to Ch_Info */ int sfb_offset_table[][MAX_SCFAC_BANDS+1], // enum WINDOW_TYPE block_type[MAX_TIME_CHANNELS], /* Block type */ AACQuantInfo* quantInfo, /* Quant info */ int numberOfChannels) /* Number of channels */ { int chanNum; int sfbNum; int lineNum; double sum,diff; /* Look for channel_pair_elements */ for (chanNum=0;chanNum<numberOfChannels;chanNum++) { if (channelInfo[chanNum].present) { if ((channelInfo[chanNum].cpe)&&(channelInfo[chanNum].ch_is_left)) { int leftChan=chanNum; int rightChan=channelInfo[chanNum].paired_ch; MS_Info *msInfo; msInfo = &(channelInfo[leftChan].ms_info); if (msInfo->is_present) { int numGroups = quantInfo[leftChan].num_window_groups; int maxSfb = quantInfo[leftChan].max_sfb; int g,w,line_offset; int startWindow,stopWindow; // w=0; /* Perform sum and differencing on bands in which ms_used flag */ /* has been set. */ // line_offset=0; startWindow = 0; for (g=0;g<numGroups;g++) { int numWindows = quantInfo[leftChan].window_group_length[g]; stopWindow = startWindow + numWindows; for (sfbNum=0;sfbNum<maxSfb;sfbNum++) { /* Enable MS mask */ if ((msInfo->ms_used[g*maxSfb+sfbNum]) || (msInfo->is_present==2)) { for (w=startWindow;w<stopWindow;w++) { line_offset = w*BLOCK_LEN_SHORT; for (lineNum=sfb_offset_table[leftChan][sfbNum];lineNum<sfb_offset_table[leftChan][sfbNum+1];lineNum++) { sum=spectrum[leftChan][line_offset+lineNum]; diff=spectrum[rightChan][line_offset+lineNum]; spectrum[leftChan][line_offset+lineNum] = (sum+diff); spectrum[rightChan][line_offset+lineNum] = (sum-diff); } /* for (lineNum... */ } /* for (w=start... */ } /* if (msInfo... */ } /* for (sfbNum... */ startWindow = stopWindow; } /* for (g... */ } /* if (ms_info.is_present... */ } /* if (channelInfo... */ } /* if (channelInfo[chanNum].present */ } /* for (chanNum... */ }