yading@11: /*
yading@11:  * Copyright (C) 2012-2013 Michael Niedermayer (michaelni@gmx.at)
yading@11:  *
yading@11:  * This file is part of libswresample
yading@11:  *
yading@11:  * libswresample is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * libswresample is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with libswresample; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "libavutil/avassert.h"
yading@11: #include "swresample_internal.h"
yading@11: 
yading@11: #include "noise_shaping_data.c"
yading@11: 
yading@11: void swri_get_dither(SwrContext *s, void *dst, int len, unsigned seed, enum AVSampleFormat noise_fmt) {
yading@11:     double scale = s->dither.noise_scale;
yading@11: #define TMP_EXTRA 2
yading@11:     double *tmp = av_malloc((len + TMP_EXTRA) * sizeof(double));
yading@11:     int i;
yading@11: 
yading@11:     for(i=0; i<len + TMP_EXTRA; i++){
yading@11:         double v;
yading@11:         seed = seed* 1664525 + 1013904223;
yading@11: 
yading@11:         switch(s->dither.method){
yading@11:             case SWR_DITHER_RECTANGULAR: v= ((double)seed) / UINT_MAX - 0.5; break;
yading@11:             default:
yading@11:                 av_assert0(s->dither.method < SWR_DITHER_NB);
yading@11:                 v = ((double)seed) / UINT_MAX;
yading@11:                 seed = seed*1664525 + 1013904223;
yading@11:                 v-= ((double)seed) / UINT_MAX;
yading@11:                 break;
yading@11:         }
yading@11:         tmp[i] = v;
yading@11:     }
yading@11: 
yading@11:     for(i=0; i<len; i++){
yading@11:         double v;
yading@11: 
yading@11:         switch(s->dither.method){
yading@11:             default:
yading@11:                 av_assert0(s->dither.method < SWR_DITHER_NB);
yading@11:                 v = tmp[i];
yading@11:                 break;
yading@11:             case SWR_DITHER_TRIANGULAR_HIGHPASS :
yading@11:                 v = (- tmp[i] + 2*tmp[i+1] - tmp[i+2]) / sqrt(6);
yading@11:                 break;
yading@11:         }
yading@11: 
yading@11:         v*= scale;
yading@11: 
yading@11:         switch(noise_fmt){
yading@11:             case AV_SAMPLE_FMT_S16P: ((int16_t*)dst)[i] = v; break;
yading@11:             case AV_SAMPLE_FMT_S32P: ((int32_t*)dst)[i] = v; break;
yading@11:             case AV_SAMPLE_FMT_FLTP: ((float  *)dst)[i] = v; break;
yading@11:             case AV_SAMPLE_FMT_DBLP: ((double *)dst)[i] = v; break;
yading@11:             default: av_assert0(0);
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     av_free(tmp);
yading@11: }
yading@11: 
yading@11: int swri_dither_init(SwrContext *s, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt)
yading@11: {
yading@11:     int i;
yading@11:     double scale = 0;
yading@11: 
yading@11:     if (s->dither.method > SWR_DITHER_TRIANGULAR_HIGHPASS && s->dither.method <= SWR_DITHER_NS)
yading@11:         return AVERROR(EINVAL);
yading@11: 
yading@11:     out_fmt = av_get_packed_sample_fmt(out_fmt);
yading@11:     in_fmt  = av_get_packed_sample_fmt( in_fmt);
yading@11: 
yading@11:     if(in_fmt == AV_SAMPLE_FMT_FLT || in_fmt == AV_SAMPLE_FMT_DBL){
yading@11:         if(out_fmt == AV_SAMPLE_FMT_S32) scale = 1.0/(1L<<31);
yading@11:         if(out_fmt == AV_SAMPLE_FMT_S16) scale = 1.0/(1L<<15);
yading@11:         if(out_fmt == AV_SAMPLE_FMT_U8 ) scale = 1.0/(1L<< 7);
yading@11:     }
yading@11:     if(in_fmt == AV_SAMPLE_FMT_S32 && out_fmt == AV_SAMPLE_FMT_S16) scale = 1L<<16;
yading@11:     if(in_fmt == AV_SAMPLE_FMT_S32 && out_fmt == AV_SAMPLE_FMT_U8 ) scale = 1L<<24;
yading@11:     if(in_fmt == AV_SAMPLE_FMT_S16 && out_fmt == AV_SAMPLE_FMT_U8 ) scale = 1L<<8;
yading@11: 
yading@11:     scale *= s->dither.scale;
yading@11: 
yading@11:     if (out_fmt == AV_SAMPLE_FMT_S32 && s->dither.output_sample_bits)
yading@11:         scale *= 1<<(32-s->dither.output_sample_bits);
yading@11: 
yading@11:     s->dither.ns_pos = 0;
yading@11:     s->dither.noise_scale=   scale;
yading@11:     s->dither.ns_scale   =   scale;
yading@11:     s->dither.ns_scale_1 = scale ? 1/scale : 0;
yading@11:     memset(s->dither.ns_errors, 0, sizeof(s->dither.ns_errors));
yading@11:     for (i=0; filters[i].coefs; i++) {
yading@11:         const filter_t *f = &filters[i];
yading@11:         if (fabs(s->out_sample_rate - f->rate) / f->rate <= .05 && f->name == s->dither.method) {
yading@11:             int j;
yading@11:             s->dither.ns_taps = f->len;
yading@11:             for (j=0; j<f->len; j++)
yading@11:                 s->dither.ns_coeffs[j] = f->coefs[j];
yading@11:             s->dither.ns_scale_1 *= 1 - exp(f->gain_cB * M_LN10 * 0.005) * 2 / (1<<(8*av_get_bytes_per_sample(out_fmt)));
yading@11:             break;
yading@11:         }
yading@11:     }
yading@11:     if (!filters[i].coefs && s->dither.method > SWR_DITHER_NS) {
yading@11:         av_log(s, AV_LOG_WARNING, "Requested noise shaping dither not available at this sampling rate, using triangular hp dither\n");
yading@11:         s->dither.method = SWR_DITHER_TRIANGULAR_HIGHPASS;
yading@11:     }
yading@11: 
yading@11:     av_assert0(!s->preout.count);
yading@11:     s->dither.noise = s->preout;
yading@11:     s->dither.temp  = s->preout;
yading@11:     if (s->dither.method > SWR_DITHER_NS) {
yading@11:         s->dither.noise.bps = 4;
yading@11:         s->dither.noise.fmt = AV_SAMPLE_FMT_FLTP;
yading@11:         s->dither.noise_scale = 1;
yading@11:     }
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: #define TEMPLATE_DITHER_S16
yading@11: #include "dither_template.c"
yading@11: #undef TEMPLATE_DITHER_S16
yading@11: 
yading@11: #define TEMPLATE_DITHER_S32
yading@11: #include "dither_template.c"
yading@11: #undef TEMPLATE_DITHER_S32
yading@11: 
yading@11: #define TEMPLATE_DITHER_FLT
yading@11: #include "dither_template.c"
yading@11: #undef TEMPLATE_DITHER_FLT
yading@11: 
yading@11: #define TEMPLATE_DITHER_DBL
yading@11: #include "dither_template.c"
yading@11: #undef TEMPLATE_DITHER_DBL