2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 #include "libavutil/channel_layout.h"
20 #include "libavutil/ffmath.h"
21 #include "libavutil/opt.h"
26 typedef struct ASubBoostContext {
47 static int query_formats(AVFilterContext *ctx)
49 AVFilterFormats *formats = NULL;
50 AVFilterChannelLayouts *layouts = NULL;
51 static const enum AVSampleFormat sample_fmts[] = {
57 formats = ff_make_format_list(sample_fmts);
59 return AVERROR(ENOMEM);
60 ret = ff_set_common_formats(ctx, formats);
64 layouts = ff_all_channel_counts();
66 return AVERROR(ENOMEM);
68 ret = ff_set_common_channel_layouts(ctx, layouts);
72 formats = ff_all_samplerates();
73 return ff_set_common_samplerates(ctx, formats);
76 static int get_coeffs(AVFilterContext *ctx)
78 ASubBoostContext *s = ctx->priv;
79 AVFilterLink *inlink = ctx->inputs[0];
80 double w0 = 2 * M_PI * s->cutoff / inlink->sample_rate;
81 double alpha = sin(w0) / 2 * sqrt(2. * (1. / s->slope - 1.) + 2.);
86 s->b0 = (1 - cos(w0)) / 2;
88 s->b2 = (1 - cos(w0)) / 2;
96 s->buffer_samples = inlink->sample_rate * s->delay / 1000;
101 static int config_input(AVFilterLink *inlink)
103 AVFilterContext *ctx = inlink->dst;
104 ASubBoostContext *s = ctx->priv;
106 s->buffer = ff_get_audio_buffer(inlink, inlink->sample_rate / 10);
107 s->w = ff_get_audio_buffer(inlink, 2);
108 s->write_pos = av_calloc(inlink->channels, sizeof(*s->write_pos));
109 if (!s->buffer || !s->w || !s->write_pos)
110 return AVERROR(ENOMEM);
112 return get_coeffs(ctx);
115 typedef struct ThreadData {
119 static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
121 ASubBoostContext *s = ctx->priv;
122 ThreadData *td = arg;
123 AVFrame *out = td->out;
124 AVFrame *in = td->in;
125 const double mix = ctx->is_disabled ? 0. : 1.;
126 const double wet = ctx->is_disabled ? 1. : s->wet_gain;
127 const double dry = ctx->is_disabled ? 1. : s->dry_gain;
128 const double feedback = s->feedback, decay = s->decay;
129 const double b0 = s->b0;
130 const double b1 = s->b1;
131 const double b2 = s->b2;
132 const double a1 = -s->a1;
133 const double a2 = -s->a2;
134 const int start = (in->channels * jobnr) / nb_jobs;
135 const int end = (in->channels * (jobnr+1)) / nb_jobs;
136 const int buffer_samples = s->buffer_samples;
138 for (int ch = start; ch < end; ch++) {
139 const double *src = (const double *)in->extended_data[ch];
140 double *dst = (double *)out->extended_data[ch];
141 double *buffer = (double *)s->buffer->extended_data[ch];
142 double *w = (double *)s->w->extended_data[ch];
143 int write_pos = s->write_pos[ch];
145 for (int n = 0; n < in->nb_samples; n++) {
148 out_sample = src[n] * b0 + w[0];
149 w[0] = b1 * src[n] + w[1] + a1 * out_sample;
150 w[1] = b2 * src[n] + a2 * out_sample;
152 buffer[write_pos] = buffer[write_pos] * decay + out_sample * feedback;
153 dst[n] = (src[n] * dry + buffer[write_pos] * mix) * wet;
155 if (++write_pos >= buffer_samples)
159 s->write_pos[ch] = write_pos;
165 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
167 AVFilterContext *ctx = inlink->dst;
168 AVFilterLink *outlink = ctx->outputs[0];
172 if (av_frame_is_writable(in)) {
175 out = ff_get_audio_buffer(outlink, in->nb_samples);
178 return AVERROR(ENOMEM);
180 av_frame_copy_props(out, in);
183 td.in = in; td.out = out;
184 ctx->internal->execute(ctx, filter_channels, &td, NULL, FFMIN(inlink->channels,
185 ff_filter_get_nb_threads(ctx)));
189 return ff_filter_frame(outlink, out);
192 static av_cold void uninit(AVFilterContext *ctx)
194 ASubBoostContext *s = ctx->priv;
196 av_frame_free(&s->buffer);
197 av_frame_free(&s->w);
198 av_freep(&s->write_pos);
201 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
202 char *res, int res_len, int flags)
206 ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
210 return get_coeffs(ctx);
213 #define OFFSET(x) offsetof(ASubBoostContext, x)
214 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
216 static const AVOption asubboost_options[] = {
217 { "dry", "set dry gain", OFFSET(dry_gain), AV_OPT_TYPE_DOUBLE, {.dbl=0.7}, 0, 1, FLAGS },
218 { "wet", "set wet gain", OFFSET(wet_gain), AV_OPT_TYPE_DOUBLE, {.dbl=0.7}, 0, 1, FLAGS },
219 { "decay", "set decay", OFFSET(decay), AV_OPT_TYPE_DOUBLE, {.dbl=0.7}, 0, 1, FLAGS },
220 { "feedback", "set feedback", OFFSET(feedback), AV_OPT_TYPE_DOUBLE, {.dbl=0.9}, 0, 1, FLAGS },
221 { "cutoff", "set cutoff", OFFSET(cutoff), AV_OPT_TYPE_DOUBLE, {.dbl=100}, 50, 900, FLAGS },
222 { "slope", "set slope", OFFSET(slope), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0.0001, 1, FLAGS },
223 { "delay", "set delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE, {.dbl=20}, 1, 100, FLAGS },
227 AVFILTER_DEFINE_CLASS(asubboost);
229 static const AVFilterPad inputs[] = {
232 .type = AVMEDIA_TYPE_AUDIO,
233 .filter_frame = filter_frame,
234 .config_props = config_input,
239 static const AVFilterPad outputs[] = {
242 .type = AVMEDIA_TYPE_AUDIO,
247 AVFilter ff_af_asubboost = {
249 .description = NULL_IF_CONFIG_SMALL("Boost subwoofer frequencies."),
250 .query_formats = query_formats,
251 .priv_size = sizeof(ASubBoostContext),
252 .priv_class = &asubboost_class,
256 .process_command = process_command,
257 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL |
258 AVFILTER_FLAG_SLICE_THREADS,