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- /*
- * LAME MP3 encoding engine
- *
- * Copyright (c) 1999 Mark Taylor
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This library 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
- * Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
- */
- /* $Id: encoder.c,v 1.43 2001/03/12 04:38:35 markt Exp $ */
- #ifdef HAVE_CONFIG_H
- #include <config.h>
- #endif
- #include <assert.h>
- #include "lame.h"
- #include "util.h"
- #include "newmdct.h"
- #include "psymodel.h"
- #include "quantize.h"
- #include "quantize_pvt.h"
- #include "bitstream.h"
- #include "VbrTag.h"
- #ifdef WITH_DMALLOC
- #include <dmalloc.h>
- #endif
- /*
- * auto-adjust of ATH, useful for low volume
- * Gabriel Bouvigne 3 feb 2001
- *
- * modifies some values in
- * gfp->internal_flags->ATH
- * (gfc->ATH)
- */
- void
- adjust_ATH( lame_global_flags* const gfp,
- FLOAT8 tot_ener[2][4] )
- {
- lame_internal_flags* const gfc = gfp->internal_flags;
- int gr, channel;
- if (gfc->ATH->use_adjust) {
- FLOAT8 max_val = 0;
- for ( gr = 0; gr < gfc->mode_gr; ++gr )
- for ( channel = 0; channel < gfc->channels_out; ++channel )
- max_val = Max( max_val, tot_ener[gr][channel] );
- /* scale to 0..1, and then rescale to 0..32767 */
- max_val *= 32767/1e13;
- /* adjust ATH depending on range of maximum value
- */
- if (vbr_mtrh == gfp->VBR) {
- /* this code reduces slowly the ATH (speed of 12 dB per second)
- * with some supporting stages to limit the reduction
- * 640 -> ~17 dB
- * :
- * 32640 -> ~0.01 dB
- */
- FLOAT8
- x = Max (640, 320*(int)(max_val/320));
- x = x/32768;
- gfc->ATH->adjust *= gfc->ATH->decay;
- if (gfc->ATH->adjust < x) /* but not more than f(x) dB */
- gfc->ATH->adjust = x;
- }
- else {
- #ifdef OLD_ATH_AUTO_ADJUST
- if (0.5 < max_val / 32768) { /* value above 50 % */
- gfc->ATH->adjust = 1.0; /* do not reduce ATH */
- }
- else if (0.3 < max_val / 32768) { /* value above 30 % */
- gfc->ATH->adjust *= 0.955; /* reduce by ~0.2 dB */
- if (gfc->ATH->adjust < 0.3) /* but ~5 dB in maximum */
- gfc->ATH->adjust = 0.3;
- }
- else { /* value below 30 % */
- gfc->ATH->adjust *= 0.93; /* reduce by ~0.3 dB */
- if (gfc->ATH->adjust < 0.01) /* but 20 dB in maximum */
- gfc->ATH->adjust = 0.01;
- }
- #else /* jd - 27 feb 2001 */
- /* continuous curves based on approximation */
- /* to GB's original values */
- FLOAT8 max_val_n = max_val / 32768;
- FLOAT8 adj_lim_new;
- /* For an increase in approximate loudness, */
- /* set ATH adjust to adjust_limit immediately*/
- /* after a delay of one frame. */
- /* For a loudness decrease, reduce ATH adjust*/
- /* towards adjust_limit gradually. */
- if( max_val_n > 0.25) { /* sqrt((1 - 0.01) / 15.84) from curve below*/
- if( gfc->ATH->adjust >= 1.0) {
- gfc->ATH->adjust = 1.0;
- } else { /* preceding frame has lower ATH adjust; */
- /* ascend only to the preceding adjust_limit */
- /* in case there is leading low volume */
- if( gfc->ATH->adjust < gfc->ATH->adjust_limit) {
- gfc->ATH->adjust = gfc->ATH->adjust_limit;
- }
- }
- gfc->ATH->adjust_limit = 1.0;
- } else { /* adjustment curve (parabolic) */
- adj_lim_new = 15.84 * (max_val_n * max_val_n) + 0.01;
- if( gfc->ATH->adjust >= adj_lim_new) { /* descend gradually */
- gfc->ATH->adjust *= adj_lim_new * 0.075 + 0.925;
- if( gfc->ATH->adjust < adj_lim_new) { /* stop descent */
- gfc->ATH->adjust = adj_lim_new;
- }
- } else { /* ascend */
- if( gfc->ATH->adjust_limit >= adj_lim_new) {
- gfc->ATH->adjust = adj_lim_new;
- } else { /* preceding frame has lower ATH adjust; */
- /* ascend only to the preceding adjust_limit */
- if( gfc->ATH->adjust < gfc->ATH->adjust_limit) {
- gfc->ATH->adjust = gfc->ATH->adjust_limit;
- }
- }
- }
- gfc->ATH->adjust_limit = adj_lim_new;
- }
- #endif
- }
- }
- }
- /************************************************************************
- *
- * encodeframe() Layer 3
- *
- * encode a single frame
- *
- ************************************************************************
- lame_encode_frame()
- gr 0 gr 1
- inbuf: |--------------|---------------|-------------|
- MDCT output: |--------------|---------------|-------------|
- FFT's <---------1024---------->
- <---------1024-------->
- inbuf = buffer of PCM data size=MP3 framesize
- encoder acts on inbuf[ch][0], but output is delayed by MDCTDELAY
- so the MDCT coefficints are from inbuf[ch][-MDCTDELAY]
- psy-model FFT has a 1 granule delay, so we feed it data for the
- next granule.
- FFT is centered over granule: 224+576+224
- So FFT starts at: 576-224-MDCTDELAY
- MPEG2: FFT ends at: BLKSIZE+576-224-MDCTDELAY
- MPEG1: FFT ends at: BLKSIZE+2*576-224-MDCTDELAY (1904)
- FFT starts at 576-224-MDCTDELAY (304) = 576-FFTOFFSET
- */
- typedef FLOAT8 chgrdata[2][2];
- int lame_encode_mp3_frame ( // Output
- lame_global_flags* const gfp, // Context
- sample_t* inbuf_l, // Input
- sample_t* inbuf_r, // Input
- unsigned char* mp3buf, // Output
- int mp3buf_size ) // Output
- {
- #ifdef macintosh /* PLL 14/04/2000 */
- static FLOAT8 xr[2][2][576];
- static int l3_enc[2][2][576];
- #else
- FLOAT8 xr[2][2][576];
- int l3_enc[2][2][576];
- #endif
- int mp3count;
- III_psy_ratio masking_LR[2][2]; /*LR masking & energy */
- III_psy_ratio masking_MS[2][2]; /*MS masking & energy */
- III_psy_ratio (*masking)[2][2]; /*pointer to selected maskings*/
- III_scalefac_t scalefac[2][2];
- const sample_t *inbuf[2];
- lame_internal_flags *gfc=gfp->internal_flags;
- FLOAT8 tot_ener[2][4];
- FLOAT8 ms_ener_ratio[2]={.5,.5};
- chgrdata pe,pe_MS;
- chgrdata *pe_use;
- int ch,gr,mean_bits;
- int bitsPerFrame;
- int check_ms_stereo;
- FLOAT8 ms_ratio_next = 0.;
- FLOAT8 ms_ratio_prev = 0.;
- memset((char *) masking_LR, 0, sizeof(masking_LR));
- memset((char *) masking_MS, 0, sizeof(masking_MS));
- memset((char *) scalefac, 0, sizeof(scalefac));
- inbuf[0]=inbuf_l;
- inbuf[1]=inbuf_r;
- check_ms_stereo = (gfp->mode == JOINT_STEREO);
- gfc->mode_ext = MPG_MD_LR_LR;
- if (gfc->lame_encode_frame_init==0 ) {
- gfc->lame_encode_frame_init=1;
-
- /* padding method as described in
- * "MPEG-Layer3 / Bitstream Syntax and Decoding"
- * by Martin Sieler, Ralph Sperschneider
- *
- * note: there is no padding for the very first frame
- *
- * Robert.Hegemann@gmx.de 2000-06-22
- */
-
- gfc->frac_SpF = ((gfp->version+1)*72000L*gfp->brate) % gfp->out_samplerate;
- gfc->slot_lag = gfc->frac_SpF;
-
- /* check FFT will not use a negative starting offset */
- #if 576 < FFTOFFSET
- # error FFTOFFSET greater than 576: FFT uses a negative offset
- #endif
- /* check if we have enough data for FFT */
- assert(gfc->mf_size>=(BLKSIZE+gfp->framesize-FFTOFFSET));
- /* check if we have enough data for polyphase filterbank */
- /* it needs 1152 samples + 286 samples ignored for one granule */
- /* 1152+576+286 samples for two granules */
- assert(gfc->mf_size>=(286+576*(1+gfc->mode_gr)));
- /* prime the MDCT/polyphase filterbank with a short block */
- {
- int i,j;
- sample_t primebuff0[286+1152+576];
- sample_t primebuff1[286+1152+576];
- for (i=0, j=0; i<286+576*(1+gfc->mode_gr); ++i) {
- if (i<576*gfc->mode_gr) {
- primebuff0[i]=0;
- if (gfc->channels_out==2)
- primebuff1[i]=0;
- }else{
- primebuff0[i]=inbuf[0][j];
- if (gfc->channels_out==2)
- primebuff1[i]=inbuf[1][j];
- ++j;
- }
- }
- /* polyphase filtering / mdct */
- for ( gr = 0; gr < gfc->mode_gr; gr++ ) {
- for ( ch = 0; ch < gfc->channels_out; ch++ ) {
- gfc->l3_side.gr[gr].ch[ch].tt.block_type=SHORT_TYPE;
- }
- }
- mdct_sub48(gfc, primebuff0, primebuff1, xr);
- }
-
- iteration_init(gfp);
-
- /* prepare for ATH auto adjustment:
- * we want to decrease the ATH by 12 dB per second
- */ {
- FLOAT8 frame_duration = 576. * gfc->mode_gr / gfp->out_samplerate;
- gfc->ATH->decay = pow(10., -12./10. * frame_duration);
- gfc->ATH->adjust = 1.0;
- gfc->ATH->adjust_limit = 0.01;
- }
- }
- /********************** padding *****************************/
- switch (gfp->padding_type) {
- case 0:
- gfc->padding=0;
- break;
- case 1:
- gfc->padding=1;
- break;
- case 2:
- default:
- if (gfp->VBR!=vbr_off) {
- gfc->padding=0;
- } else {
- if (gfp->disable_reservoir) {
- gfc->padding = 0;
- /* if the user specified --nores, dont very gfc->padding either */
- /* tiny changes in frac_SpF rounding will cause file differences */
- }else{
- /* padding method as described in
- * "MPEG-Layer3 / Bitstream Syntax and Decoding"
- * by Martin Sieler, Ralph Sperschneider
- *
- * note: there is no padding for the very first frame
- *
- * Robert.Hegemann@gmx.de 2000-06-22
- */
- gfc->slot_lag -= gfc->frac_SpF;
- if (gfc->slot_lag < 0) {
- gfc->slot_lag += gfp->out_samplerate;
- gfc->padding = 1;
- } else {
- gfc->padding = 0;
- }
- } /* reservoir enabled */
- }
- }
- if (gfc->psymodel) {
- /* psychoacoustic model
- * psy model has a 1 granule (576) delay that we must compensate for
- * (mt 6/99).
- */
- int ret;
- const sample_t *bufp[2]; /* address of beginning of left & right granule */
- int blocktype[2];
- ms_ratio_prev=gfc->ms_ratio[gfc->mode_gr-1];
- for (gr=0; gr < gfc->mode_gr ; gr++) {
- for ( ch = 0; ch < gfc->channels_out; ch++ )
- bufp[ch] = &inbuf[ch][576 + gr*576-FFTOFFSET];
- if (gfc->nsPsy.use) {
- ret=L3psycho_anal_ns( gfp, bufp, gr,
- &gfc->ms_ratio[gr],&ms_ratio_next,
- masking_LR, masking_MS,
- pe[gr],pe_MS[gr],tot_ener[gr],blocktype);
- } else {
- ret=L3psycho_anal( gfp, bufp, gr,
- &gfc->ms_ratio[gr],&ms_ratio_next,
- masking_LR, masking_MS,
- pe[gr],pe_MS[gr],tot_ener[gr],blocktype);
- }
- if (ret!=0) return -4;
- for ( ch = 0; ch < gfc->channels_out; ch++ )
- gfc->l3_side.gr[gr].ch[ch].tt.block_type=blocktype[ch];
- if (check_ms_stereo) {
- ms_ener_ratio[gr] = tot_ener[gr][2]+tot_ener[gr][3];
- if (ms_ener_ratio[gr]>0)
- ms_ener_ratio[gr] = tot_ener[gr][3]/ms_ener_ratio[gr];
- }
- }
- }else{
- for (gr=0; gr < gfc->mode_gr ; gr++)
- for ( ch = 0; ch < gfc->channels_out; ch++ ) {
- gfc->l3_side.gr[gr].ch[ch].tt.block_type=NORM_TYPE;
- pe_MS[gr][ch]=pe[gr][ch]=700;
- }
- }
- /* auto-adjust of ATH, useful for low volume */
- adjust_ATH( gfp, tot_ener );
- /* block type flags */
- for( gr = 0; gr < gfc->mode_gr; gr++ ) {
- for ( ch = 0; ch < gfc->channels_out; ch++ ) {
- gr_info *cod_info = &gfc->l3_side.gr[gr].ch[ch].tt;
- cod_info->mixed_block_flag = 0; /* never used by this model */
- if (cod_info->block_type == NORM_TYPE )
- cod_info->window_switching_flag = 0;
- else
- cod_info->window_switching_flag = 1;
- }
- }
- /* polyphase filtering / mdct */
- mdct_sub48(gfc, inbuf[0], inbuf[1], xr);
- /* re-order the short blocks, for more efficient encoding below */
- for (gr = 0; gr < gfc->mode_gr; gr++) {
- for (ch = 0; ch < gfc->channels_out; ch++) {
- gr_info *cod_info = &gfc->l3_side.gr[gr].ch[ch].tt;
- if (cod_info->block_type==SHORT_TYPE) {
- freorder(gfc->scalefac_band.s,xr[gr][ch]);
- }
- }
- }
-
- /* use m/s gfc->channels_out? */
- if (check_ms_stereo) {
- int gr0 = 0, gr1 = gfc->mode_gr-1;
- /* make sure block type is the same in each channel */
- check_ms_stereo =
- (gfc->l3_side.gr[gr0].ch[0].tt.block_type==gfc->l3_side.gr[gr0].ch[1].tt.block_type) &&
- (gfc->l3_side.gr[gr1].ch[0].tt.block_type==gfc->l3_side.gr[gr1].ch[1].tt.block_type);
- }
-
- /* Here will be selected MS or LR coding of the 2 stereo channels */
- assert ( gfc->mode_ext == MPG_MD_LR_LR );
- gfc->mode_ext = MPG_MD_LR_LR;
-
- if (gfp->force_ms) {
- gfc->mode_ext = MPG_MD_MS_LR;
- } else if (check_ms_stereo) {
- /* ms_ratio = is scaled, for historical reasons, to look like
- a ratio of side_channel / total.
- 0 = signal is 100% mono
- .5 = L & R uncorrelated
- */
-
- /* [0] and [1] are the results for the two granules in MPEG-1,
- * in MPEG-2 it's only a faked averaging of the same value
- * _prev is the value of the last granule of the previous frame
- * _next is the value of the first granule of the next frame
- */
- FLOAT8 ms_ratio_ave1;
- FLOAT8 ms_ratio_ave2;
- FLOAT8 threshold1 = 0.35;
- FLOAT8 threshold2 = 0.45;
- /* take an average */
- if (gfc->mode_gr==1) {
- /* MPEG2 - no second granule */
- ms_ratio_ave1 = 0.33 * ( gfc->ms_ratio[0] + ms_ratio_prev + ms_ratio_next );
- ms_ratio_ave2 = gfc->ms_ratio[0];
- }else{
- ms_ratio_ave1 = 0.25 * ( gfc->ms_ratio[0] + gfc->ms_ratio[1] + ms_ratio_prev + ms_ratio_next );
- ms_ratio_ave2 = 0.50 * ( gfc->ms_ratio[0] + gfc->ms_ratio[1] );
- }
-
- if (gfp->mode_automs) {
- if ( gfp->compression_ratio < 11.025 ) {
- /* 11.025 => 1, 6.3 => 0 */
- double thr = (gfp->compression_ratio - 6.3) / (11.025 - 6.3);
- if (thr<0) thr=0;
- threshold1 *= thr;
- threshold2 *= thr;
- }
- }
-
- if ((ms_ratio_ave1 < threshold1 && ms_ratio_ave2 < threshold2) || gfc->nsPsy.use) {
- int sum_pe_MS = pe_MS[0][0] + pe_MS[0][1] + pe_MS[1][0] + pe_MS[1][1];
- int sum_pe_LR = pe [0][0] + pe [0][1] + pe [1][0] + pe [1][1];
-
- /* based on PE: M/S coding would not use much more bits than L/R coding */
-
- if (sum_pe_MS <= 1.07 * sum_pe_LR && !gfc->nsPsy.use) gfc->mode_ext = MPG_MD_MS_LR;
- if (sum_pe_MS <= 1.00 * sum_pe_LR && gfc->nsPsy.use) gfc->mode_ext = MPG_MD_MS_LR;
- }
- }
- /* copy data for MP3 frame analyzer */
- if (gfp->analysis && gfc->pinfo != NULL) {
- for ( gr = 0; gr < gfc->mode_gr; gr++ ) {
- for ( ch = 0; ch < gfc->channels_out; ch++ ) {
- gfc->pinfo->ms_ratio[gr]=gfc->ms_ratio[gr];
- gfc->pinfo->ms_ener_ratio[gr]=ms_ener_ratio[gr];
- gfc->pinfo->blocktype[gr][ch]=
- gfc->l3_side.gr[gr].ch[ch].tt.block_type;
- memcpy(gfc->pinfo->xr[gr][ch],xr[gr][ch],sizeof(xr[gr][ch]));
- /* in psymodel, LR and MS data was stored in pinfo.
- switch to MS data: */
- if (gfc->mode_ext==MPG_MD_MS_LR) {
- gfc->pinfo->pe[gr][ch]=gfc->pinfo->pe[gr][ch+2];
- gfc->pinfo->ers[gr][ch]=gfc->pinfo->ers[gr][ch+2];
- memcpy(gfc->pinfo->energy[gr][ch],gfc->pinfo->energy[gr][ch+2],
- sizeof(gfc->pinfo->energy[gr][ch]));
- }
- }
- }
- }
- /* bit and noise allocation */
- if (MPG_MD_MS_LR == gfc->mode_ext) {
- masking = &masking_MS; /* use MS masking */
- pe_use = &pe_MS;
- } else {
- masking = &masking_LR; /* use LR masking */
- pe_use = &pe;
- }
- if (gfc->nsPsy.use && (gfp->VBR == vbr_off || gfp->VBR == vbr_abr)) {
- static FLOAT fircoef[19] = {
- -0.0207887,-0.0378413,-0.0432472,-0.031183,
- 7.79609e-18,0.0467745,0.10091,0.151365,
- 0.187098,0.2,0.187098,0.151365,
- 0.10091,0.0467745,7.79609e-18,-0.031183,
- -0.0432472,-0.0378413,-0.0207887,
- };
- int i;
- FLOAT8 f;
- for(i=0;i<18;i++) gfc->nsPsy.pefirbuf[i] = gfc->nsPsy.pefirbuf[i+1];
- i=0;
- gfc->nsPsy.pefirbuf[18] = 0;
- for ( gr = 0; gr < gfc->mode_gr; gr++ ) {
- for ( ch = 0; ch < gfc->channels_out; ch++ ) {
- gfc->nsPsy.pefirbuf[18] += (*pe_use)[gr][ch];
- i++;
- }
- }
- gfc->nsPsy.pefirbuf[18] = gfc->nsPsy.pefirbuf[18] / i;
- f = 0;
- for(i=0;i<19;i++) f += gfc->nsPsy.pefirbuf[i] * fircoef[i];
- for ( gr = 0; gr < gfc->mode_gr; gr++ ) {
- for ( ch = 0; ch < gfc->channels_out; ch++ ) {
- (*pe_use)[gr][ch] *= 670 / f;
- }
- }
- }
- switch (gfp->VBR){
- default:
- case vbr_off:
- iteration_loop( gfp,*pe_use,ms_ener_ratio, xr, *masking, l3_enc, scalefac);
- break;
- case vbr_mt:
- VBR_quantize( gfp,*pe_use,ms_ener_ratio, xr, *masking, l3_enc, scalefac);
- break;
- case vbr_rh:
- case vbr_mtrh:
- VBR_iteration_loop( gfp,*pe_use,ms_ener_ratio, xr, *masking, l3_enc, scalefac);
- break;
- case vbr_abr:
- ABR_iteration_loop( gfp,*pe_use,ms_ener_ratio, xr, *masking, l3_enc, scalefac);
- break;
- }
- /* write the frame to the bitstream */
- getframebits(gfp, &bitsPerFrame, &mean_bits);
- format_bitstream( gfp, bitsPerFrame, l3_enc, scalefac);
- /* copy mp3 bit buffer into array */
- mp3count = copy_buffer(mp3buf,mp3buf_size,&gfc->bs);
- if (gfp->bWriteVbrTag) AddVbrFrame(gfp);
- /* copy data for MP3 frame analyzer */
- if (gfp->analysis && gfc->pinfo != NULL) {
- int j;
- for ( ch = 0; ch < gfc->channels_out; ch++ ) {
- for ( j = 0; j < FFTOFFSET; j++ )
- gfc->pinfo->pcmdata[ch][j] = gfc->pinfo->pcmdata[ch][j+gfp->framesize];
- for ( j = FFTOFFSET; j < 1600; j++ ) {
- gfc->pinfo->pcmdata[ch][j] = inbuf[ch][j-FFTOFFSET];
- }
- }
- set_frame_pinfo (gfp, xr, *masking, l3_enc, scalefac);
- }
-
- updateStats( gfc );
- return mp3count;
- }
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