Files
third_party_lame/libmp3lame/encoder.c
T
2002-12-14 19:19:54 +00:00

630 lines
20 KiB
C

/*
* 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.
*/
/* $Id$ */
#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"
#include "vbrquantize.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)
*/
static void
adjust_ATH( lame_global_flags* const gfp,
FLOAT8 tot_ener[2][4] )
{
lame_internal_flags* const gfc = gfp->internal_flags;
int gr, channel;
FLOAT max_pow, max_pow_alt;
FLOAT8 max_val;
if (gfc->ATH->use_adjust == 0 || gfp->athaa_loudapprox == 0) {
gfc->ATH->adjust = 1.0; /* no adjustment */
return;
}
switch( gfp->athaa_loudapprox ) {
case 1:
/* flat approximation for loudness (squared) */
max_pow = 0;
for ( gr = 0; gr < gfc->mode_gr; ++gr )
for ( channel = 0; channel < gfc->channels_out; ++channel )
max_pow = Max( max_pow, tot_ener[gr][channel] );
max_pow *= 0.25/ 5.6e13; /* scale to 0..1 (5.6e13), and tune (0.25) */
break;
case 2: /* jd - 2001 mar 12, 27, jun 30 */
{ /* loudness based on equal loudness curve; */
/* use granule with maximum combined loudness*/
FLOAT gr2_max = gfc->loudness_sq[1][0];
max_pow = gfc->loudness_sq[0][0];
if( gfc->channels_out == 2 ) {
max_pow += gfc->loudness_sq[0][1];
gr2_max += gfc->loudness_sq[1][1];
} else {
max_pow += max_pow;
gr2_max += gr2_max;
}
if( gfc->mode_gr == 2 ) {
max_pow = Max( max_pow, gr2_max );
}
max_pow *= 0.5; /* max_pow approaches 1.0 for full band noise*/
break;
}
default:
max_pow = 0;
assert(0);
}
/* jd - 2001 mar 31, jun 30 */
/* user tuning of ATH adjustment region */
max_pow_alt = max_pow;
max_pow *= gfc->athaa_sensitivity_p;
if (gfc->presetTune.use)
max_pow_alt *= pow( 10.0, gfc->presetTune.athadjust_safe_athaasensitivity / -10.0 );
/* adjust ATH depending on range of maximum value
*/
switch ( gfc->ATH->use_adjust ) {
case 1:
max_val = sqrt( max_pow ); /* GB's original code requires a maximum */
max_val *= 32768; /* sample or loudness value up to 32768 */
/* by Gabriel Bouvigne */
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;
}
break;
case 2:
max_val = Min( max_pow, 1.0 ) * 32768; /* adapt for RH's adjust */
{ /* by Robert Hegemann */
/* this code reduces slowly the ATH (speed of 12 dB per second)
*/
FLOAT8
/*x = Max (640, 320*(int)(max_val/320)); */
x = Max (32, 32*(int)(max_val/32));
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;
}
break;
case 3:
{ /* jd - 2001 feb27, mar12,20, jun30, jul22 */
/* continuous curves based on approximation */
/* to GB's original values. */
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. */
/* max_pow is a loudness squared or a power. */
if( max_pow > 0.03125) { /* ((1 - 0.000625)/ 31.98) from curve below */
if( gfc->ATH->adjust >= 1.0) {
gfc->ATH->adjust = 1.0;
if (gfc->presetTune.use) {
if (max_pow_alt > gfc->presetTune.athadjust_safe_noiseshaping_thre)
gfc->presetTune.athadjust_safe_noiseshaping = 1;
else
gfc->presetTune.athadjust_safe_noiseshaping = 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;
if (gfc->presetTune.use) {
if (max_pow_alt > gfc->presetTune.athadjust_safe_noiseshaping_thre)
gfc->presetTune.athadjust_safe_noiseshaping = 1;
else
gfc->presetTune.athadjust_safe_noiseshaping = 0;
}
}
}
gfc->ATH->adjust_limit = 1.0;
} else { /* adjustment curve */
/* about 32 dB maximum adjust (0.000625) */
adj_lim_new = 31.98 * max_pow + 0.000625;
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;
}
}
break;
default:
assert(0);
break;
} /* switch */
}
/***********************************************************************
*
* some simple statistics
*
* bitrate index 0: free bitrate -> not allowed in VBR mode
* : bitrates, kbps depending on MPEG version
* bitrate index 15: forbidden
*
* mode_ext:
* 0: LR
* 1: LR-i
* 2: MS
* 3: MS-i
*
***********************************************************************/
#ifdef BRHIST
/*2DO rh 20021015
I thought BRHIST was only for the frontend, so that clients
may use these stats, even if it's only a Windows DLL
I'll extend the stats for block types used
*/
static void
updateStats( lame_internal_flags * const gfc )
{
int gr, ch;
assert ( gfc->bitrate_index < 16u );
assert ( gfc->mode_ext < 4u );
/* count bitrate indices */
gfc->bitrate_stereoMode_Hist [gfc->bitrate_index] [4] ++;
gfc->bitrate_stereoMode_Hist [15] [4] ++;
/* count 'em for every mode extension in case of 2 channel encoding */
if (gfc->channels_out == 2) {
gfc->bitrate_stereoMode_Hist [gfc->bitrate_index] [gfc->mode_ext]++;
gfc->bitrate_stereoMode_Hist [15] [gfc->mode_ext]++;
}
for (gr = 0; gr < gfc->mode_gr; ++gr) {
for (ch = 0; ch < gfc->channels_out; ++ch) {
int bt = gfc->l3_side.tt[gr][ch].block_type;
int mf = gfc->l3_side.tt[gr][ch].mixed_block_flag;
if (mf) bt = 4;
gfc->bitrate_blockType_Hist [gfc->bitrate_index] [bt] ++;
gfc->bitrate_blockType_Hist [gfc->bitrate_index] [ 5] ++;
gfc->bitrate_blockType_Hist [15] [bt] ++;
gfc->bitrate_blockType_Hist [15] [ 5] ++;
}
}
}
#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 */
{
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*/
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;
FLOAT8 ms_ratio_next = 0.;
FLOAT8 ms_ratio_prev = 0.;
inbuf[0]=inbuf_l;
inbuf[1]=inbuf_r;
if (gfc->lame_encode_frame_init==0 ) {
/* prime the MDCT/polyphase filterbank with a short block */
int i,j;
sample_t primebuff0[286+1152+576];
sample_t primebuff1[286+1152+576];
gfc->lame_encode_frame_init=1;
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.tt[gr][ch].block_type=SHORT_TYPE;
}
}
mdct_sub48(gfc, primebuff0, primebuff1);
/* 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)));
}
/********************** padding *****************************/
/* 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 2000-06-22
*/
gfc->padding = FALSE;
if ((gfc->slot_lag -= gfc->frac_SpF) < 0) {
gfc->slot_lag += gfp->out_samplerate;
gfc->padding = TRUE;
}
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;
if (gfp->mode == JOINT_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];
}
/* block type flags */
for ( ch = 0; ch < gfc->channels_out; ch++ ) {
gr_info *cod_info = &gfc->l3_side.tt[gr][ch];
cod_info->block_type=blocktype[ch];
cod_info->mixed_block_flag = 0;
}
}
}else{
memset((char *) masking_LR, 0, sizeof(masking_LR));
memset((char *) masking_MS, 0, sizeof(masking_MS));
for (gr=0; gr < gfc->mode_gr ; gr++)
for ( ch = 0; ch < gfc->channels_out; ch++ ) {
gfc->l3_side.tt[gr][ch].block_type=NORM_TYPE;
gfc->l3_side.tt[gr][ch].mixed_block_flag=0;
pe_MS[gr][ch]=pe[gr][ch]=700;
}
}
/* auto-adjust of ATH, useful for low volume */
adjust_ATH( gfp, tot_ener );
/* polyphase filtering / mdct */
mdct_sub48(gfc, inbuf[0], inbuf[1]);
/* Here will be selected MS or LR coding of the 2 stereo channels */
gfc->mode_ext = MPG_MD_LR_LR;
if (gfp->force_ms) {
gfc->mode_ext = MPG_MD_MS_LR;
} else if (gfp->mode == JOINT_STEREO) {
int check_ms_stereo = 1;
/* 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
*/
if (!gfc->nsPsy.use) {
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 && 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)
check_ms_stereo = 0;
}
if (check_ms_stereo) {
FLOAT8 sum_pe_MS = 0;
FLOAT8 sum_pe_LR = 0;
for ( gr = 0; gr < gfc->mode_gr; gr++ ) {
for ( ch = 0; ch < gfc->channels_out; ch++ ) {
sum_pe_MS += pe_MS[gr][ch];
sum_pe_LR += pe[gr][ch];
}
}
/*2DO rh 20021015
change the following to
if (sum_pe_MS <= sum_pe_LR)
gfc->mode_ext = MPG_MD_MS_LR;
*/
/* based on PE: M/S coding would not use much more bits than L/R */
if ((!gfc->nsPsy.use && sum_pe_MS <= 1.07 * sum_pe_LR)
|| (gfc->nsPsy.use && sum_pe_MS <= 1.00 * sum_pe_LR)) {
gr_info *gi0 = &gfc->l3_side.tt[0][0];
gr_info *gi1 = &gfc->l3_side.tt[gfc->mode_gr-1][0];
if (gi0[0].block_type == gi0[1].block_type
&& gi1[0].block_type == gi1[1].block_type)
gfc->mode_ext = MPG_MD_MS_LR;
}
}
}
/* bit and noise allocation */
if (gfc->mode_ext == MPG_MD_MS_LR) {
masking = &masking_MS; /* use MS masking */
pe_use = &pe_MS;
} else {
masking = &masking_LR; /* use LR masking */
pe_use = &pe;
}
#if defined(HAVE_GTK)
/* 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.tt[gr][ch].block_type;
gfc->pinfo->pe[gr][ch]=(*pe_use)[gr][ch];
memcpy(gfc->pinfo->xr[gr][ch], &gfc->l3_side.tt[gr][ch].xr,
sizeof(FLOAT8)*576);
/* in psymodel, LR and MS data was stored in pinfo.
switch to MS data: */
if (gfc->mode_ext==MPG_MD_MS_LR) {
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]));
}
}
}
}
#endif
if (gfc->nsPsy.use && (gfp->VBR == vbr_off || gfp->VBR == vbr_abr)) {
static FLOAT fircoef[9] = {
-0.0207887 *5, -0.0378413*5, -0.0432472*5, -0.031183*5,
7.79609e-18*5, 0.0467745*5, 0.10091*5, 0.151365*5,
0.187098*5
};
int i;
FLOAT8 f;
for(i=0;i<18;i++) gfc->nsPsy.pefirbuf[i] = gfc->nsPsy.pefirbuf[i+1];
f = 0.0;
for ( gr = 0; gr < gfc->mode_gr; gr++ )
for ( ch = 0; ch < gfc->channels_out; ch++ )
f += (*pe_use)[gr][ch];
gfc->nsPsy.pefirbuf[18] = f;
f = gfc->nsPsy.pefirbuf[9];
for (i=0;i<9;i++)
f += (gfc->nsPsy.pefirbuf[i]+gfc->nsPsy.pefirbuf[18-i]) * fircoef[i];
f = (670*5*gfc->mode_gr*gfc->channels_out)/f;
for ( gr = 0; gr < gfc->mode_gr; gr++ ) {
for ( ch = 0; ch < gfc->channels_out; ch++ ) {
(*pe_use)[gr][ch] *= f;
}
}
}
switch (gfp->VBR){
default:
case vbr_off:
iteration_loop( gfp,*pe_use,ms_ener_ratio, *masking);
break;
case vbr_mt:
case vbr_rh:
case vbr_mtrh:
VBR_iteration_loop( gfp,*pe_use,ms_ener_ratio, *masking);
break;
case vbr_abr:
ABR_iteration_loop( gfp,*pe_use,ms_ener_ratio, *masking);
break;
}
/* write the frame to the bitstream */
format_bitstream(gfp);
/* copy mp3 bit buffer into array */
mp3count = copy_buffer(gfc,mp3buf,mp3buf_size,1);
if (gfp->bWriteVbrTag) AddVbrFrame(gfp);
#if defined(HAVE_GTK)
if (gfp->analysis && gfc->pinfo != NULL) {
for ( ch = 0; ch < gfc->channels_out; ch++ ) {
int j;
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, *masking);
}
#endif
#ifdef BRHIST
updateStats( gfc );
#endif
return mp3count;
}