2 * Copyright (c) 2008 Rob Sykes
3 * Copyright (c) 2017 Paul B Mahol
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/channel_layout.h"
23 #include "libavutil/opt.h"
28 typedef struct AudioContrastContext {
31 void (*filter)(void **dst, const void **src,
32 int nb_samples, int channels, float contrast);
33 } AudioContrastContext;
35 #define OFFSET(x) offsetof(AudioContrastContext, x)
36 #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
38 static const AVOption acontrast_options[] = {
39 { "contrast", "set contrast", OFFSET(contrast), AV_OPT_TYPE_FLOAT, {.dbl=33}, 0, 100, A },
43 AVFILTER_DEFINE_CLASS(acontrast);
45 static int query_formats(AVFilterContext *ctx)
47 AVFilterFormats *formats = NULL;
48 AVFilterChannelLayouts *layouts = NULL;
49 static const enum AVSampleFormat sample_fmts[] = {
50 AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_FLTP,
51 AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_DBLP,
56 formats = ff_make_format_list(sample_fmts);
58 return AVERROR(ENOMEM);
59 ret = ff_set_common_formats(ctx, formats);
63 layouts = ff_all_channel_counts();
65 return AVERROR(ENOMEM);
67 ret = ff_set_common_channel_layouts(ctx, layouts);
71 formats = ff_all_samplerates();
72 return ff_set_common_samplerates(ctx, formats);
75 static void filter_flt(void **d, const void **s,
76 int nb_samples, int channels,
79 const float *src = s[0];
83 for (n = 0; n < nb_samples; n++) {
84 for (c = 0; c < channels; c++) {
85 float d = src[c] * M_PI_2;
87 dst[c] = sinf(d + contrast * sinf(d * 4));
95 static void filter_dbl(void **d, const void **s,
96 int nb_samples, int channels,
99 const double *src = s[0];
103 for (n = 0; n < nb_samples; n++) {
104 for (c = 0; c < channels; c++) {
105 double d = src[c] * M_PI_2;
107 dst[c] = sin(d + contrast * sin(d * 4));
115 static void filter_fltp(void **d, const void **s,
116 int nb_samples, int channels,
121 for (c = 0; c < channels; c++) {
122 const float *src = s[c];
125 for (n = 0; n < nb_samples; n++) {
126 float d = src[n] * M_PI_2;
128 dst[n] = sinf(d + contrast * sinf(d * 4));
133 static void filter_dblp(void **d, const void **s,
134 int nb_samples, int channels,
139 for (c = 0; c < channels; c++) {
140 const double *src = s[c];
143 for (n = 0; n < nb_samples; n++) {
144 double d = src[n] * M_PI_2;
146 dst[n] = sin(d + contrast * sin(d * 4));
151 static int config_input(AVFilterLink *inlink)
153 AVFilterContext *ctx = inlink->dst;
154 AudioContrastContext *s = ctx->priv;
156 switch (inlink->format) {
157 case AV_SAMPLE_FMT_FLT: s->filter = filter_flt; break;
158 case AV_SAMPLE_FMT_DBL: s->filter = filter_dbl; break;
159 case AV_SAMPLE_FMT_FLTP: s->filter = filter_fltp; break;
160 case AV_SAMPLE_FMT_DBLP: s->filter = filter_dblp; break;
166 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
168 AVFilterContext *ctx = inlink->dst;
169 AVFilterLink *outlink = ctx->outputs[0];
170 AudioContrastContext *s = ctx->priv;
173 if (av_frame_is_writable(in)) {
176 out = ff_get_audio_buffer(outlink, in->nb_samples);
179 return AVERROR(ENOMEM);
181 av_frame_copy_props(out, in);
184 s->filter((void **)out->extended_data, (const void **)in->extended_data,
185 in->nb_samples, in->channels, s->contrast / 750);
190 return ff_filter_frame(outlink, out);
193 static const AVFilterPad inputs[] = {
196 .type = AVMEDIA_TYPE_AUDIO,
197 .filter_frame = filter_frame,
198 .config_props = config_input,
203 static const AVFilterPad outputs[] = {
206 .type = AVMEDIA_TYPE_AUDIO,
211 AVFilter ff_af_acontrast = {
213 .description = NULL_IF_CONFIG_SMALL("Simple audio dynamic range compression/expansion filter."),
214 .query_formats = query_formats,
215 .priv_size = sizeof(AudioContrastContext),
216 .priv_class = &acontrast_class,