/* * MP3 quantization * * Copyright (c) 1999 Mark Taylor * * 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. */ #include #include "globalflags.h" #include "util.h" #include "l3side.h" #include "quantize.h" #include "l3bitstream.h" #include "reservoir.h" #include "quantize-pvt.h" #ifdef HAVEGTK #include "gtkanal.h" #endif #define DEBUG FLOAT8 calc_sfb_ave_noise(FLOAT8 *xr, FLOAT8 *xr34, int stride, int bw, FLOAT8 sfpow) { int j; FLOAT8 xfsf=0; FLOAT8 sfpow34 = pow(sfpow,3.0/4.0); for ( j=0; j < stride*bw ; j += stride) { int ix; FLOAT8 temp,temp2; /* ix=(int)( xr34[j]/sfpow34 + 0.4054);*/ ix=floor( xr34[j]/sfpow34); if (ix > IXMAX_VAL) return -1.0; temp = fabs(xr[j])- pow43[ix]*sfpow; if (ix < IXMAX_VAL) { temp2 = fabs(xr[j])- pow43[ix+1]*sfpow; if (temp2 11.25 */ /* 31.75 */ sf = -20.5; delsf = 32; sf_ok=1000; for (i=0; i<7; i++) { delsf /= 2; sfpow = pow(2.0,sf); xfsf = calc_sfb_ave_noise(xr,xr34,stride,bw,sfpow); if (xfsf < 0) { /* scalefactors too small */ sf += delsf; }else{ #ifdef DEBUG if (stride==1 && sfb==2 && gf.frameNum==50) { printf("sfb=%i q=%f xfsf=%f masking=%f sf_ok=%f \n",sfb,sf, 10*log10(1e-20+xfsf),10*log10(1e-20+l3_xmin),sf_ok); } #endif if (sf_ok==1000) sf_ok=sf; if (xfsf > l3_xmin) { /* distortion. try a smaller scalefactor */ sf -= delsf; }else{ sf_ok=sf; sf += delsf; } } } /* sf_ok accurate to within +/- 2*final_value_of_delsf */ assert(sf_ok!=1000); /* NOTE: noise is not a monotone function of the sf, even though * the number of bits used is! do a brute force search in the * neighborhood of sf_ok: * * sf = sf_ok + 1.75 works 1% of the time * sf = sf_ok + 1.50 works 1% of the time * sf = sf_ok + 1.25 works 2% of the time * sf = sf_ok + 1.00 works 3% of the time * sf = sf_ok + 0.75 works 9% of the time * sf = sf_ok + 0.50 0 % (because it was tried above) * sf = sf_ok + 0.25 works 39% of the time * sf = sf_ok + 0.00 works the rest of the time */ sf = sf_ok + 0.75; while (sf>(sf_ok+.01)) { /* sf = sf_ok + 2*delsf was tried above, skip it: */ if (fabs(sf-(sf_ok+2*delsf)) < .01) sf -=.25; sfpow = pow(2.0,sf); xfsf = calc_sfb_ave_noise(xr,xr34,stride,bw,sfpow); if (xfsf > 0) { if (xfsf <= l3_xmin) return sf; } sf -= .25; } return sf_ok; } /************************************************************************ * * VBR_iteration_loop() * * ************************************************************************/ void VBR_iteration_loop_new (FLOAT8 pe[2][2], FLOAT8 ms_ener_ratio[2], FLOAT8 xr_org[2][2][576], III_psy_ratio ratio[2][2], III_side_info_t * l3_side, int l3_enc[2][2][576], III_scalefac_t scalefac[2][2], frame_params * fr_ps) { III_psy_xmin l3_xmin[2][2]; layer *info; FLOAT8 xr[2][2][576]; FLOAT8 masking_lower_db; FLOAT8 ifqstep,ol_sf,vbr_sf; int start,end,bw,sfb, i,ch, gr, over; /* iteration_init(xr_org,l3_side,l3_enc,fr_ps); */ info = fr_ps->header; /* Adjust allowed masking based on quality setting */ /* db_lower varies from -10 to +8 db */ masking_lower_db = -10 + 2*gf.VBR_q; /* adjust by -6(min)..0(max) depending on bitrate */ masking_lower = pow(10.0,masking_lower_db/10); masking_lower = 1; /* copy data to be quantized into xr */ for(gr = 0; gr < gf.mode_gr; gr++) { if (convert_mdct) ms_convert(xr[gr],xr_org[gr]); else memcpy(xr[gr],xr_org[gr],sizeof(FLOAT8)*2*576); } for (gr = 0; gr < gf.mode_gr; gr++) { for (ch = 0; ch < gf.stereo; ch++) { FLOAT8 xr34[576]; gr_info *cod_info = &l3_side->gr[gr].ch[ch].tt; int shortblock; over = 0; shortblock = (cod_info->block_type == SHORT_TYPE); ifqstep = ( cod_info->scalefac_scale == 0 ) ? .5 : 1.0; for(i=0;i<576;i++) { FLOAT8 temp=fabs(xr[gr][ch][i]); xr34[i]=sqrt(sqrt(temp)*temp); } /*init_outer_loop(xr,&l3_xmin,scalefac,gr,stereo,l3_side,ratio,ch); */ calc_xmin( xr[gr][ch], &ratio[gr][ch], cod_info, &l3_xmin[gr][ch]); if (shortblock) { for ( sfb = 0; sfb < SBPSY_s; sfb++ ) { for ( i = 0; i < 3; i++ ) { start = scalefac_band.s[ sfb ]; end = scalefac_band.s[ sfb+1 ]; bw = end - start; vbr_sf = find_scalefac(&xr[gr][ch][3*start+i],&xr34[3*start+i],3,sfb, masking_lower*l3_xmin[gr][ch].s[sfb][i],bw); ol_sf = (cod_info->global_gain-210.0)/4.0; ol_sf -= 2*cod_info->subblock_gain[i]; ol_sf -= ifqstep*scalefac[gr][ch].s[sfb][i]; { FLOAT8 xfsf; xfsf = calc_sfb_ave_noise(&xr[gr][ch][3*start+i],&xr34[3*start+i], 3,bw,pow(2.0,ol_sf)); if (xfsf > masking_lower*l3_xmin[gr][ch].s[sfb][i]) { over++; } } } } }else{ for ( sfb = 0; sfb < SBPSY_l; sfb++ ) { start = scalefac_band.l[ sfb ]; end = scalefac_band.l[ sfb+1 ]; bw = end - start; vbr_sf = find_scalefac(&xr[gr][ch][start],&xr34[start],1,sfb, masking_lower*l3_xmin[gr][ch].l[sfb],bw); /* compare with outer_loop scalefacs */ ol_sf = (cod_info->global_gain-210.0)/4.0; ol_sf -= ifqstep*scalefac[gr][ch].l[sfb]; if (cod_info->preflag && sfb>=11) ol_sf -= ifqstep*pretab[sfb]; { FLOAT8 xfsf; xfsf=calc_sfb_ave_noise(&xr[gr][ch][start],&xr34[start],1,bw,pow(2.0,ol_sf)); if (xfsf > masking_lower*l3_xmin[gr][ch].l[sfb]) { over++; } } } } /* compute scalefactors */ // printf("%i %i %i new vbr over=%i \n",gf.frameNum,gr,ch,over); } /* ch */ } /* gr */ }