647 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			647 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * COpyright (c) 2002 Daniel Pouzzner
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|  * Copyright (c) 1999 Chris Bagwell
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|  * Copyright (c) 1999 Nick Bailey
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|  * Copyright (c) 2007 Rob Sykes <robs@users.sourceforge.net>
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|  * Copyright (c) 2013 Paul B Mahol
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|  * Copyright (c) 2014 Andrew Kelley
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| /**
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|  * @file
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|  * audio multiband compand filter
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|  */
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| 
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| #include "libavutil/avstring.h"
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| #include "libavutil/ffmath.h"
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| #include "libavutil/opt.h"
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| #include "libavutil/samplefmt.h"
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| #include "audio.h"
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| #include "avfilter.h"
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| #include "internal.h"
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| 
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| typedef struct CompandSegment {
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|     double x, y;
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|     double a, b;
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| } CompandSegment;
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| 
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| typedef struct CompandT {
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|     CompandSegment *segments;
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|     int nb_segments;
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|     double in_min_lin;
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|     double out_min_lin;
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|     double curve_dB;
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|     double gain_dB;
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| } CompandT;
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| 
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| #define N 4
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| 
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| typedef struct PrevCrossover {
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|     double in;
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|     double out_low;
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|     double out_high;
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| } PrevCrossover[N * 2];
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| 
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| typedef struct Crossover {
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|   PrevCrossover *previous;
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|   size_t         pos;
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|   double         coefs[3 *(N+1)];
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| } Crossover;
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| 
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| typedef struct CompBand {
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|     CompandT transfer_fn;
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|     double *attack_rate;
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|     double *decay_rate;
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|     double *volume;
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|     double delay;
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|     double topfreq;
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|     Crossover filter;
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|     AVFrame *delay_buf;
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|     size_t delay_size;
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|     ptrdiff_t delay_buf_ptr;
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|     size_t delay_buf_cnt;
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| } CompBand;
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| 
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| typedef struct MCompandContext {
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|     const AVClass *class;
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| 
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|     char *args;
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| 
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|     int nb_bands;
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|     CompBand *bands;
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|     AVFrame *band_buf1, *band_buf2, *band_buf3;
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|     int band_samples;
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|     size_t delay_buf_size;
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| } MCompandContext;
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| 
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| #define OFFSET(x) offsetof(MCompandContext, x)
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| #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
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| 
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| static const AVOption mcompand_options[] = {
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|     { "args", "set parameters for each band", OFFSET(args), AV_OPT_TYPE_STRING, { .str = "0.005,0.1 6 -47/-40,-34/-34,-17/-33 100 | 0.003,0.05 6 -47/-40,-34/-34,-17/-33 400 | 0.000625,0.0125 6 -47/-40,-34/-34,-15/-33 1600 | 0.0001,0.025 6 -47/-40,-34/-34,-31/-31,-0/-30 6400 | 0,0.025 6 -38/-31,-28/-28,-0/-25 22000" }, 0, 0, A },
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|     { NULL }
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| };
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| 
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| AVFILTER_DEFINE_CLASS(mcompand);
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| 
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| static av_cold void uninit(AVFilterContext *ctx)
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| {
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|     MCompandContext *s = ctx->priv;
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|     int i;
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| 
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|     av_frame_free(&s->band_buf1);
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|     av_frame_free(&s->band_buf2);
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|     av_frame_free(&s->band_buf3);
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| 
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|     if (s->bands) {
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|         for (i = 0; i < s->nb_bands; i++) {
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|             av_freep(&s->bands[i].attack_rate);
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|             av_freep(&s->bands[i].decay_rate);
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|             av_freep(&s->bands[i].volume);
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|             av_freep(&s->bands[i].transfer_fn.segments);
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|             av_freep(&s->bands[i].filter.previous);
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|             av_frame_free(&s->bands[i].delay_buf);
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|         }
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|     }
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|     av_freep(&s->bands);
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| }
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| 
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| static void count_items(char *item_str, int *nb_items, char delimiter)
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| {
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|     char *p;
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| 
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|     *nb_items = 1;
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|     for (p = item_str; *p; p++) {
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|         if (*p == delimiter)
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|             (*nb_items)++;
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|     }
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| }
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| 
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| static void update_volume(CompBand *cb, double in, int ch)
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| {
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|     double delta = in - cb->volume[ch];
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| 
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|     if (delta > 0.0)
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|         cb->volume[ch] += delta * cb->attack_rate[ch];
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|     else
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|         cb->volume[ch] += delta * cb->decay_rate[ch];
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| }
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| 
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| static double get_volume(CompandT *s, double in_lin)
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| {
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|     CompandSegment *cs;
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|     double in_log, out_log;
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|     int i;
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| 
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|     if (in_lin <= s->in_min_lin)
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|         return s->out_min_lin;
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| 
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|     in_log = log(in_lin);
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| 
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|     for (i = 1; i < s->nb_segments; i++)
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|         if (in_log <= s->segments[i].x)
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|             break;
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|     cs = &s->segments[i - 1];
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|     in_log -= cs->x;
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|     out_log = cs->y + in_log * (cs->a * in_log + cs->b);
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| 
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|     return exp(out_log);
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| }
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| 
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| static int parse_points(char *points, int nb_points, double radius,
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|                         CompandT *s, AVFilterContext *ctx)
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| {
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|     int new_nb_items, num;
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|     char *saveptr = NULL;
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|     char *p = points;
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|     int i;
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| 
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| #define S(x) s->segments[2 * ((x) + 1)]
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|     for (i = 0, new_nb_items = 0; i < nb_points; i++) {
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|         char *tstr = av_strtok(p, ",", &saveptr);
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|         p = NULL;
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|         if (!tstr || sscanf(tstr, "%lf/%lf", &S(i).x, &S(i).y) != 2) {
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|             av_log(ctx, AV_LOG_ERROR,
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|                     "Invalid and/or missing input/output value.\n");
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|             return AVERROR(EINVAL);
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|         }
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|         if (i && S(i - 1).x > S(i).x) {
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|             av_log(ctx, AV_LOG_ERROR,
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|                     "Transfer function input values must be increasing.\n");
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|             return AVERROR(EINVAL);
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|         }
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|         S(i).y -= S(i).x;
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|         av_log(ctx, AV_LOG_DEBUG, "%d: x=%f y=%f\n", i, S(i).x, S(i).y);
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|         new_nb_items++;
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|     }
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|     num = new_nb_items;
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| 
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|     /* Add 0,0 if necessary */
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|     if (num == 0 || S(num - 1).x)
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|         num++;
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| 
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| #undef S
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| #define S(x) s->segments[2 * (x)]
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|     /* Add a tail off segment at the start */
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|     S(0).x = S(1).x - 2 * s->curve_dB;
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|     S(0).y = S(1).y;
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|     num++;
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| 
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|     /* Join adjacent colinear segments */
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|     for (i = 2; i < num; i++) {
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|         double g1 = (S(i - 1).y - S(i - 2).y) * (S(i - 0).x - S(i - 1).x);
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|         double g2 = (S(i - 0).y - S(i - 1).y) * (S(i - 1).x - S(i - 2).x);
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|         int j;
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| 
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|         if (fabs(g1 - g2))
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|             continue;
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|         num--;
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|         for (j = --i; j < num; j++)
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|             S(j) = S(j + 1);
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|     }
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| 
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|     for (i = 0; i < s->nb_segments; i += 2) {
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|         s->segments[i].y += s->gain_dB;
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|         s->segments[i].x *= M_LN10 / 20;
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|         s->segments[i].y *= M_LN10 / 20;
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|     }
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| 
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| #define L(x) s->segments[i - (x)]
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|     for (i = 4; i < s->nb_segments; i += 2) {
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|         double x, y, cx, cy, in1, in2, out1, out2, theta, len, r;
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| 
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|         L(4).a = 0;
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|         L(4).b = (L(2).y - L(4).y) / (L(2).x - L(4).x);
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| 
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|         L(2).a = 0;
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|         L(2).b = (L(0).y - L(2).y) / (L(0).x - L(2).x);
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| 
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|         theta = atan2(L(2).y - L(4).y, L(2).x - L(4).x);
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|         len = hypot(L(2).x - L(4).x, L(2).y - L(4).y);
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|         r = FFMIN(radius, len);
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|         L(3).x = L(2).x - r * cos(theta);
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|         L(3).y = L(2).y - r * sin(theta);
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| 
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|         theta = atan2(L(0).y - L(2).y, L(0).x - L(2).x);
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|         len = hypot(L(0).x - L(2).x, L(0).y - L(2).y);
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|         r = FFMIN(radius, len / 2);
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|         x = L(2).x + r * cos(theta);
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|         y = L(2).y + r * sin(theta);
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| 
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|         cx = (L(3).x + L(2).x + x) / 3;
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|         cy = (L(3).y + L(2).y + y) / 3;
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| 
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|         L(2).x = x;
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|         L(2).y = y;
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| 
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|         in1  = cx - L(3).x;
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|         out1 = cy - L(3).y;
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|         in2  = L(2).x - L(3).x;
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|         out2 = L(2).y - L(3).y;
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|         L(3).a = (out2 / in2 - out1 / in1) / (in2 - in1);
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|         L(3).b = out1 / in1 - L(3).a * in1;
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|     }
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|     L(3).x = 0;
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|     L(3).y = L(2).y;
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| 
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|     s->in_min_lin  = exp(s->segments[1].x);
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|     s->out_min_lin = exp(s->segments[1].y);
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| 
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|     return 0;
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| }
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| 
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| static void square_quadratic(double const *x, double *y)
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| {
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|     y[0] = x[0] * x[0];
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|     y[1] = 2 * x[0] * x[1];
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|     y[2] = 2 * x[0] * x[2] + x[1] * x[1];
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|     y[3] = 2 * x[1] * x[2];
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|     y[4] = x[2] * x[2];
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| }
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| 
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| static int crossover_setup(AVFilterLink *outlink, Crossover *p, double frequency)
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| {
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|     double w0 = 2 * M_PI * frequency / outlink->sample_rate;
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|     double Q = sqrt(.5), alpha = sin(w0) / (2*Q);
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|     double x[9], norm;
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|     int i;
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| 
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|     if (w0 > M_PI)
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|         return AVERROR(EINVAL);
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| 
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|     x[0] =  (1 - cos(w0))/2;           /* Cf. filter_LPF in biquads.c */
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|     x[1] =   1 - cos(w0);
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|     x[2] =  (1 - cos(w0))/2;
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|     x[3] =  (1 + cos(w0))/2;           /* Cf. filter_HPF in biquads.c */
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|     x[4] = -(1 + cos(w0));
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|     x[5] =  (1 + cos(w0))/2;
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|     x[6] =   1 + alpha;
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|     x[7] =  -2*cos(w0);
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|     x[8] =   1 - alpha;
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| 
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|     for (norm = x[6], i = 0; i < 9; ++i)
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|         x[i] /= norm;
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| 
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|     square_quadratic(x    , p->coefs);
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|     square_quadratic(x + 3, p->coefs + 5);
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|     square_quadratic(x + 6, p->coefs + 10);
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| 
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|     p->previous = av_calloc(outlink->ch_layout.nb_channels, sizeof(*p->previous));
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|     if (!p->previous)
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|         return AVERROR(ENOMEM);
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| 
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|     return 0;
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| }
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| 
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| static int config_output(AVFilterLink *outlink)
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| {
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|     AVFilterContext *ctx  = outlink->src;
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|     MCompandContext *s    = ctx->priv;
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|     int ret, ch, i, k, new_nb_items, nb_bands;
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|     char *p = s->args, *saveptr = NULL;
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|     int max_delay_size = 0;
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| 
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|     count_items(s->args, &nb_bands, '|');
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|     s->nb_bands = FFMAX(1, nb_bands);
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| 
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|     s->bands = av_calloc(nb_bands, sizeof(*s->bands));
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|     if (!s->bands)
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|         return AVERROR(ENOMEM);
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| 
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|     for (i = 0, new_nb_items = 0; i < nb_bands; i++) {
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|         int nb_points, nb_attacks, nb_items = 0;
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|         char *tstr2, *tstr = av_strtok(p, "|", &saveptr);
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|         char *p2, *p3, *saveptr2 = NULL, *saveptr3 = NULL;
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|         double radius;
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| 
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|         if (!tstr)
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|             return AVERROR(EINVAL);
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|         p = NULL;
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| 
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|         p2 = tstr;
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|         count_items(tstr, &nb_items, ' ');
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|         tstr2 = av_strtok(p2, " ", &saveptr2);
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|         if (!tstr2) {
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|             av_log(ctx, AV_LOG_ERROR, "at least one attacks/decays rate is mandatory\n");
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|             return AVERROR(EINVAL);
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|         }
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|         p2 = NULL;
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|         p3 = tstr2;
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| 
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|         count_items(tstr2, &nb_attacks, ',');
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|         if (!nb_attacks || nb_attacks & 1) {
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|             av_log(ctx, AV_LOG_ERROR, "number of attacks rate plus decays rate must be even\n");
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|             return AVERROR(EINVAL);
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|         }
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| 
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|         s->bands[i].attack_rate = av_calloc(outlink->ch_layout.nb_channels, sizeof(double));
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|         s->bands[i].decay_rate = av_calloc(outlink->ch_layout.nb_channels, sizeof(double));
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|         s->bands[i].volume = av_calloc(outlink->ch_layout.nb_channels, sizeof(double));
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|         if (!s->bands[i].attack_rate || !s->bands[i].decay_rate || !s->bands[i].volume)
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|             return AVERROR(ENOMEM);
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| 
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|         for (k = 0; k < FFMIN(nb_attacks / 2, outlink->ch_layout.nb_channels); k++) {
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|             char *tstr3 = av_strtok(p3, ",", &saveptr3);
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| 
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|             p3 = NULL;
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|             sscanf(tstr3, "%lf", &s->bands[i].attack_rate[k]);
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|             tstr3 = av_strtok(p3, ",", &saveptr3);
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|             sscanf(tstr3, "%lf", &s->bands[i].decay_rate[k]);
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| 
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|             if (s->bands[i].attack_rate[k] > 1.0 / outlink->sample_rate) {
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|                 s->bands[i].attack_rate[k] = 1.0 - exp(-1.0 / (outlink->sample_rate * s->bands[i].attack_rate[k]));
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|             } else {
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|                 s->bands[i].attack_rate[k] = 1.0;
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|             }
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| 
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|             if (s->bands[i].decay_rate[k] > 1.0 / outlink->sample_rate) {
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|                 s->bands[i].decay_rate[k] = 1.0 - exp(-1.0 / (outlink->sample_rate * s->bands[i].decay_rate[k]));
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|             } else {
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|                 s->bands[i].decay_rate[k] = 1.0;
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|             }
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|         }
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| 
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|         for (ch = k; ch < outlink->ch_layout.nb_channels; ch++) {
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|             s->bands[i].attack_rate[ch] = s->bands[i].attack_rate[k - 1];
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|             s->bands[i].decay_rate[ch]  = s->bands[i].decay_rate[k - 1];
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|         }
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| 
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|         tstr2 = av_strtok(p2, " ", &saveptr2);
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|         if (!tstr2) {
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|             av_log(ctx, AV_LOG_ERROR, "transfer function curve in dB must be set\n");
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|             return AVERROR(EINVAL);
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|         }
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|         sscanf(tstr2, "%lf", &s->bands[i].transfer_fn.curve_dB);
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| 
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|         radius = s->bands[i].transfer_fn.curve_dB * M_LN10 / 20.0;
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| 
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|         tstr2 = av_strtok(p2, " ", &saveptr2);
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|         if (!tstr2) {
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|             av_log(ctx, AV_LOG_ERROR, "transfer points missing\n");
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|             return AVERROR(EINVAL);
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|         }
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| 
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|         count_items(tstr2, &nb_points, ',');
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|         s->bands[i].transfer_fn.nb_segments = (nb_points + 4) * 2;
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|         s->bands[i].transfer_fn.segments = av_calloc(s->bands[i].transfer_fn.nb_segments,
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|                                                      sizeof(CompandSegment));
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|         if (!s->bands[i].transfer_fn.segments)
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|             return AVERROR(ENOMEM);
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| 
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|         ret = parse_points(tstr2, nb_points, radius, &s->bands[i].transfer_fn, ctx);
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|         if (ret < 0) {
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|             av_log(ctx, AV_LOG_ERROR, "transfer points parsing failed\n");
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|             return ret;
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|         }
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| 
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|         tstr2 = av_strtok(p2, " ", &saveptr2);
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|         if (!tstr2) {
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|             av_log(ctx, AV_LOG_ERROR, "crossover_frequency is missing\n");
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|             return AVERROR(EINVAL);
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|         }
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| 
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|         new_nb_items += sscanf(tstr2, "%lf", &s->bands[i].topfreq) == 1;
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|         if (s->bands[i].topfreq < 0 || s->bands[i].topfreq >= outlink->sample_rate / 2) {
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|             av_log(ctx, AV_LOG_ERROR, "crossover_frequency: %f, should be >=0 and lower than half of sample rate: %d.\n", s->bands[i].topfreq, outlink->sample_rate / 2);
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|             return AVERROR(EINVAL);
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|         }
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| 
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|         if (s->bands[i].topfreq != 0) {
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|             ret = crossover_setup(outlink, &s->bands[i].filter, s->bands[i].topfreq);
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|             if (ret < 0)
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|                 return ret;
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|         }
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| 
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|         tstr2 = av_strtok(p2, " ", &saveptr2);
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|         if (tstr2) {
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|             sscanf(tstr2, "%lf", &s->bands[i].delay);
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|             max_delay_size = FFMAX(max_delay_size, s->bands[i].delay * outlink->sample_rate);
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| 
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|             tstr2 = av_strtok(p2, " ", &saveptr2);
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|             if (tstr2) {
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|                 double initial_volume;
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| 
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|                 sscanf(tstr2, "%lf", &initial_volume);
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|                 initial_volume = pow(10.0, initial_volume / 20);
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| 
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|                 for (k = 0; k < outlink->ch_layout.nb_channels; k++) {
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|                     s->bands[i].volume[k] = initial_volume;
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|                 }
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| 
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|                 tstr2 = av_strtok(p2, " ", &saveptr2);
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|                 if (tstr2) {
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|                     sscanf(tstr2, "%lf", &s->bands[i].transfer_fn.gain_dB);
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|     }
 | |
|     s->nb_bands = new_nb_items;
 | |
| 
 | |
|     for (i = 0; max_delay_size > 0 && i < s->nb_bands; i++) {
 | |
|         s->bands[i].delay_buf = ff_get_audio_buffer(outlink, max_delay_size);
 | |
|         if (!s->bands[i].delay_buf)
 | |
|             return AVERROR(ENOMEM);
 | |
|     }
 | |
|     s->delay_buf_size = max_delay_size;
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| #define CONVOLVE _ _ _ _
 | |
| 
 | |
| static void crossover(int ch, Crossover *p,
 | |
|                       double *ibuf, double *obuf_low,
 | |
|                       double *obuf_high, size_t len)
 | |
| {
 | |
|     double out_low, out_high;
 | |
| 
 | |
|     while (len--) {
 | |
|         p->pos = p->pos ? p->pos - 1 : N - 1;
 | |
| #define _ out_low += p->coefs[j] * p->previous[ch][p->pos + j].in \
 | |
|             - p->coefs[2*N+2 + j] * p->previous[ch][p->pos + j].out_low, j++;
 | |
|         {
 | |
|             int j = 1;
 | |
|             out_low = p->coefs[0] * *ibuf;
 | |
|             CONVOLVE
 | |
|             *obuf_low++ = out_low;
 | |
|         }
 | |
| #undef _
 | |
| #define _ out_high += p->coefs[j+N+1] * p->previous[ch][p->pos + j].in \
 | |
|             - p->coefs[2*N+2 + j] * p->previous[ch][p->pos + j].out_high, j++;
 | |
|         {
 | |
|             int j = 1;
 | |
|             out_high = p->coefs[N+1] * *ibuf;
 | |
|             CONVOLVE
 | |
|             *obuf_high++ = out_high;
 | |
|         }
 | |
|         p->previous[ch][p->pos + N].in = p->previous[ch][p->pos].in = *ibuf++;
 | |
|         p->previous[ch][p->pos + N].out_low = p->previous[ch][p->pos].out_low = out_low;
 | |
|         p->previous[ch][p->pos + N].out_high = p->previous[ch][p->pos].out_high = out_high;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static int mcompand_channel(MCompandContext *c, CompBand *l, double *ibuf, double *obuf, int len, int ch)
 | |
| {
 | |
|     int i;
 | |
| 
 | |
|     for (i = 0; i < len; i++) {
 | |
|         double level_in_lin, level_out_lin, checkbuf;
 | |
|         /* Maintain the volume fields by simulating a leaky pump circuit */
 | |
|         update_volume(l, fabs(ibuf[i]), ch);
 | |
| 
 | |
|         /* Volume memory is updated: perform compand */
 | |
|         level_in_lin = l->volume[ch];
 | |
|         level_out_lin = get_volume(&l->transfer_fn, level_in_lin);
 | |
| 
 | |
|         if (c->delay_buf_size <= 0) {
 | |
|             checkbuf = ibuf[i] * level_out_lin;
 | |
|             obuf[i] = checkbuf;
 | |
|         } else {
 | |
|             double *delay_buf = (double *)l->delay_buf->extended_data[ch];
 | |
| 
 | |
|             /* FIXME: note that this lookahead algorithm is really lame:
 | |
|                the response to a peak is released before the peak
 | |
|                arrives. */
 | |
| 
 | |
|             /* because volume application delays differ band to band, but
 | |
|                total delay doesn't, the volume is applied in an iteration
 | |
|                preceding that in which the sample goes to obuf, except in
 | |
|                the band(s) with the longest vol app delay.
 | |
| 
 | |
|                the offset between delay_buf_ptr and the sample to apply
 | |
|                vol to, is a constant equal to the difference between this
 | |
|                band's delay and the longest delay of all the bands. */
 | |
| 
 | |
|             if (l->delay_buf_cnt >= l->delay_size) {
 | |
|                 checkbuf =
 | |
|                     delay_buf[(l->delay_buf_ptr +
 | |
|                                c->delay_buf_size -
 | |
|                                l->delay_size) % c->delay_buf_size] * level_out_lin;
 | |
|                 delay_buf[(l->delay_buf_ptr + c->delay_buf_size -
 | |
|                            l->delay_size) % c->delay_buf_size] = checkbuf;
 | |
|             }
 | |
|             if (l->delay_buf_cnt >= c->delay_buf_size) {
 | |
|                 obuf[i] = delay_buf[l->delay_buf_ptr];
 | |
|             } else {
 | |
|                 l->delay_buf_cnt++;
 | |
|             }
 | |
|             delay_buf[l->delay_buf_ptr++] = ibuf[i];
 | |
|             l->delay_buf_ptr %= c->delay_buf_size;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 | |
| {
 | |
|     AVFilterContext  *ctx = inlink->dst;
 | |
|     AVFilterLink *outlink = ctx->outputs[0];
 | |
|     MCompandContext *s    = ctx->priv;
 | |
|     AVFrame *out, *abuf, *bbuf, *cbuf;
 | |
|     int ch, band, i;
 | |
| 
 | |
|     out = ff_get_audio_buffer(outlink, in->nb_samples);
 | |
|     if (!out) {
 | |
|         av_frame_free(&in);
 | |
|         return AVERROR(ENOMEM);
 | |
|     }
 | |
| 
 | |
|     if (s->band_samples < in->nb_samples) {
 | |
|         av_frame_free(&s->band_buf1);
 | |
|         av_frame_free(&s->band_buf2);
 | |
|         av_frame_free(&s->band_buf3);
 | |
| 
 | |
|         s->band_buf1 = ff_get_audio_buffer(outlink, in->nb_samples);
 | |
|         s->band_buf2 = ff_get_audio_buffer(outlink, in->nb_samples);
 | |
|         s->band_buf3 = ff_get_audio_buffer(outlink, in->nb_samples);
 | |
|         s->band_samples = in->nb_samples;
 | |
|     }
 | |
| 
 | |
|     for (ch = 0; ch < outlink->ch_layout.nb_channels; ch++) {
 | |
|         double *a, *dst = (double *)out->extended_data[ch];
 | |
| 
 | |
|         for (band = 0, abuf = in, bbuf = s->band_buf2, cbuf = s->band_buf1; band < s->nb_bands; band++) {
 | |
|             CompBand *b = &s->bands[band];
 | |
| 
 | |
|             if (b->topfreq) {
 | |
|                 crossover(ch, &b->filter, (double *)abuf->extended_data[ch],
 | |
|                           (double *)bbuf->extended_data[ch], (double *)cbuf->extended_data[ch], in->nb_samples);
 | |
|             } else {
 | |
|                 bbuf = abuf;
 | |
|                 abuf = cbuf;
 | |
|             }
 | |
| 
 | |
|             if (abuf == in)
 | |
|                 abuf = s->band_buf3;
 | |
|             mcompand_channel(s, b, (double *)bbuf->extended_data[ch], (double *)abuf->extended_data[ch], out->nb_samples, ch);
 | |
|             a = (double *)abuf->extended_data[ch];
 | |
|             for (i = 0; i < out->nb_samples; i++) {
 | |
|                 dst[i] += a[i];
 | |
|             }
 | |
| 
 | |
|             FFSWAP(AVFrame *, abuf, cbuf);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     out->pts = in->pts;
 | |
|     av_frame_free(&in);
 | |
|     return ff_filter_frame(outlink, out);
 | |
| }
 | |
| 
 | |
| static int request_frame(AVFilterLink *outlink)
 | |
| {
 | |
|     AVFilterContext *ctx = outlink->src;
 | |
|     int ret;
 | |
| 
 | |
|     ret = ff_request_frame(ctx->inputs[0]);
 | |
| 
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| static const AVFilterPad mcompand_inputs[] = {
 | |
|     {
 | |
|         .name           = "default",
 | |
|         .type           = AVMEDIA_TYPE_AUDIO,
 | |
|         .filter_frame   = filter_frame,
 | |
|     },
 | |
| };
 | |
| 
 | |
| static const AVFilterPad mcompand_outputs[] = {
 | |
|     {
 | |
|         .name          = "default",
 | |
|         .type          = AVMEDIA_TYPE_AUDIO,
 | |
|         .request_frame = request_frame,
 | |
|         .config_props  = config_output,
 | |
|     },
 | |
| };
 | |
| 
 | |
| 
 | |
| const AVFilter ff_af_mcompand = {
 | |
|     .name           = "mcompand",
 | |
|     .description    = NULL_IF_CONFIG_SMALL(
 | |
|             "Multiband Compress or expand audio dynamic range."),
 | |
|     .priv_size      = sizeof(MCompandContext),
 | |
|     .priv_class     = &mcompand_class,
 | |
|     .uninit         = uninit,
 | |
|     FILTER_INPUTS(mcompand_inputs),
 | |
|     FILTER_OUTPUTS(mcompand_outputs),
 | |
|     FILTER_SINGLE_SAMPLEFMT(AV_SAMPLE_FMT_DBLP),
 | |
| };
 |