FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavfilter/af_volume.c
Date: 2024-07-24 19:24:46
Exec Total Coverage
Lines: 123 207 59.4%
Functions: 9 14 64.3%
Branches: 50 110 45.5%

Line Branch Exec Source
1 /*
2 * Copyright (c) 2011 Stefano Sabatini
3 * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22 /**
23 * @file
24 * audio volume filter
25 */
26
27 #include "libavutil/channel_layout.h"
28 #include "libavutil/common.h"
29 #include "libavutil/eval.h"
30 #include "libavutil/ffmath.h"
31 #include "libavutil/float_dsp.h"
32 #include "libavutil/mem.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/replaygain.h"
35
36 #include "audio.h"
37 #include "avfilter.h"
38 #include "formats.h"
39 #include "internal.h"
40 #include "af_volume.h"
41
42 static const char * const precision_str[] = {
43 "fixed", "float", "double"
44 };
45
46 static const char *const var_names[] = {
47 "n", ///< frame number (starting at zero)
48 "nb_channels", ///< number of channels
49 "nb_consumed_samples", ///< number of samples consumed by the filter
50 "nb_samples", ///< number of samples in the current frame
51 #if FF_API_FRAME_PKT
52 "pos", ///< position in the file of the frame
53 #endif
54 "pts", ///< frame presentation timestamp
55 "sample_rate", ///< sample rate
56 "startpts", ///< PTS at start of stream
57 "startt", ///< time at start of stream
58 "t", ///< time in the file of the frame
59 "tb", ///< timebase
60 "volume", ///< last set value
61 NULL
62 };
63
64 #define OFFSET(x) offsetof(VolumeContext, x)
65 #define A AV_OPT_FLAG_AUDIO_PARAM
66 #define F AV_OPT_FLAG_FILTERING_PARAM
67 #define T AV_OPT_FLAG_RUNTIME_PARAM
68
69 static const AVOption volume_options[] = {
70 { "volume", "set volume adjustment expression",
71 OFFSET(volume_expr), AV_OPT_TYPE_STRING, { .str = "1.0" }, .flags = A|F|T },
72 { "precision", "select mathematical precision",
73 OFFSET(precision), AV_OPT_TYPE_INT, { .i64 = PRECISION_FLOAT }, PRECISION_FIXED, PRECISION_DOUBLE, A|F, .unit = "precision" },
74 { "fixed", "select 8-bit fixed-point", 0, AV_OPT_TYPE_CONST, { .i64 = PRECISION_FIXED }, INT_MIN, INT_MAX, A|F, .unit = "precision" },
75 { "float", "select 32-bit floating-point", 0, AV_OPT_TYPE_CONST, { .i64 = PRECISION_FLOAT }, INT_MIN, INT_MAX, A|F, .unit = "precision" },
76 { "double", "select 64-bit floating-point", 0, AV_OPT_TYPE_CONST, { .i64 = PRECISION_DOUBLE }, INT_MIN, INT_MAX, A|F, .unit = "precision" },
77 { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_ONCE}, 0, EVAL_MODE_NB-1, .flags = A|F, .unit = "eval" },
78 { "once", "eval volume expression once", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_ONCE}, .flags = A|F, .unit = "eval" },
79 { "frame", "eval volume expression per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = A|F, .unit = "eval" },
80 { "replaygain", "Apply replaygain side data when present",
81 OFFSET(replaygain), AV_OPT_TYPE_INT, { .i64 = REPLAYGAIN_DROP }, REPLAYGAIN_DROP, REPLAYGAIN_ALBUM, A|F, .unit = "replaygain" },
82 { "drop", "replaygain side data is dropped", 0, AV_OPT_TYPE_CONST, { .i64 = REPLAYGAIN_DROP }, 0, 0, A|F, .unit = "replaygain" },
83 { "ignore", "replaygain side data is ignored", 0, AV_OPT_TYPE_CONST, { .i64 = REPLAYGAIN_IGNORE }, 0, 0, A|F, .unit = "replaygain" },
84 { "track", "track gain is preferred", 0, AV_OPT_TYPE_CONST, { .i64 = REPLAYGAIN_TRACK }, 0, 0, A|F, .unit = "replaygain" },
85 { "album", "album gain is preferred", 0, AV_OPT_TYPE_CONST, { .i64 = REPLAYGAIN_ALBUM }, 0, 0, A|F, .unit = "replaygain" },
86 { "replaygain_preamp", "Apply replaygain pre-amplification",
87 OFFSET(replaygain_preamp), AV_OPT_TYPE_DOUBLE, { .dbl = 0.0 }, -15.0, 15.0, A|F },
88 { "replaygain_noclip", "Apply replaygain clipping prevention",
89 OFFSET(replaygain_noclip), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, A|F },
90 { NULL }
91 };
92
93 AVFILTER_DEFINE_CLASS(volume);
94
95 6 static int set_expr(AVExpr **pexpr, const char *expr, void *log_ctx)
96 {
97 int ret;
98 6 AVExpr *old = NULL;
99
100
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6 if (*pexpr)
101 old = *pexpr;
102 6 ret = av_expr_parse(pexpr, expr, var_names,
103 NULL, NULL, NULL, NULL, 0, log_ctx);
104
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6 if (ret < 0) {
105 av_log(log_ctx, AV_LOG_ERROR,
106 "Error when evaluating the volume expression '%s'\n", expr);
107 *pexpr = old;
108 return ret;
109 }
110
111 6 av_expr_free(old);
112 6 return 0;
113 }
114
115 6 static av_cold int init(AVFilterContext *ctx)
116 {
117 6 VolumeContext *vol = ctx->priv;
118
119 6 vol->fdsp = avpriv_float_dsp_alloc(0);
120
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6 if (!vol->fdsp)
121 return AVERROR(ENOMEM);
122
123 6 return set_expr(&vol->volume_pexpr, vol->volume_expr, ctx);
124 }
125
126 6 static av_cold void uninit(AVFilterContext *ctx)
127 {
128 6 VolumeContext *vol = ctx->priv;
129 6 av_expr_free(vol->volume_pexpr);
130 6 av_freep(&vol->fdsp);
131 6 }
132
133 3 static int query_formats(AVFilterContext *ctx)
134 {
135 3 VolumeContext *vol = ctx->priv;
136 static const enum AVSampleFormat sample_fmts[][7] = {
137 [PRECISION_FIXED] = {
138 AV_SAMPLE_FMT_U8,
139 AV_SAMPLE_FMT_U8P,
140 AV_SAMPLE_FMT_S16,
141 AV_SAMPLE_FMT_S16P,
142 AV_SAMPLE_FMT_S32,
143 AV_SAMPLE_FMT_S32P,
144 AV_SAMPLE_FMT_NONE
145 },
146 [PRECISION_FLOAT] = {
147 AV_SAMPLE_FMT_FLT,
148 AV_SAMPLE_FMT_FLTP,
149 AV_SAMPLE_FMT_NONE
150 },
151 [PRECISION_DOUBLE] = {
152 AV_SAMPLE_FMT_DBL,
153 AV_SAMPLE_FMT_DBLP,
154 AV_SAMPLE_FMT_NONE
155 }
156 };
157 3 int ret = ff_set_common_all_channel_counts(ctx);
158
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3 if (ret < 0)
159 return ret;
160
161 3 ret = ff_set_common_formats_from_list(ctx, sample_fmts[vol->precision]);
162
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3 if (ret < 0)
163 return ret;
164
165 3 return ff_set_common_all_samplerates(ctx);
166 }
167
168 static inline void scale_samples_u8(uint8_t *dst, const uint8_t *src,
169 int nb_samples, int volume)
170 {
171 int i;
172 for (i = 0; i < nb_samples; i++)
173 dst[i] = av_clip_uint8(((((int64_t)src[i] - 128) * volume + 128) >> 8) + 128);
174 }
175
176 static inline void scale_samples_u8_small(uint8_t *dst, const uint8_t *src,
177 int nb_samples, int volume)
178 {
179 int i;
180 for (i = 0; i < nb_samples; i++)
181 dst[i] = av_clip_uint8((((src[i] - 128) * volume + 128) >> 8) + 128);
182 }
183
184 static inline void scale_samples_s16(uint8_t *dst, const uint8_t *src,
185 int nb_samples, int volume)
186 {
187 int i;
188 int16_t *smp_dst = (int16_t *)dst;
189 const int16_t *smp_src = (const int16_t *)src;
190 for (i = 0; i < nb_samples; i++)
191 smp_dst[i] = av_clip_int16(((int64_t)smp_src[i] * volume + 128) >> 8);
192 }
193
194 65 static inline void scale_samples_s16_small(uint8_t *dst, const uint8_t *src,
195 int nb_samples, int volume)
196 {
197 int i;
198 65 int16_t *smp_dst = (int16_t *)dst;
199 65 const int16_t *smp_src = (const int16_t *)src;
200
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529265 for (i = 0; i < nb_samples; i++)
201 529200 smp_dst[i] = av_clip_int16((smp_src[i] * volume + 128) >> 8);
202 65 }
203
204 static inline void scale_samples_s32(uint8_t *dst, const uint8_t *src,
205 int nb_samples, int volume)
206 {
207 int i;
208 int32_t *smp_dst = (int32_t *)dst;
209 const int32_t *smp_src = (const int32_t *)src;
210 for (i = 0; i < nb_samples; i++)
211 smp_dst[i] = av_clipl_int32((((int64_t)smp_src[i] * volume + 128) >> 8));
212 }
213
214 3 static av_cold void volume_init(VolumeContext *vol)
215 {
216 3 vol->samples_align = 1;
217
218
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3 switch (av_get_packed_sample_fmt(vol->sample_fmt)) {
219 case AV_SAMPLE_FMT_U8:
220 if (vol->volume_i < 0x1000000)
221 vol->scale_samples = scale_samples_u8_small;
222 else
223 vol->scale_samples = scale_samples_u8;
224 break;
225 1 case AV_SAMPLE_FMT_S16:
226
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1 if (vol->volume_i < 0x10000)
227 1 vol->scale_samples = scale_samples_s16_small;
228 else
229 vol->scale_samples = scale_samples_s16;
230 1 break;
231 1 case AV_SAMPLE_FMT_S32:
232 1 vol->scale_samples = scale_samples_s32;
233 1 break;
234 1 case AV_SAMPLE_FMT_FLT:
235 1 vol->samples_align = 4;
236 1 break;
237 case AV_SAMPLE_FMT_DBL:
238 vol->samples_align = 8;
239 break;
240 }
241
242 #if ARCH_X86
243 3 ff_volume_init_x86(vol);
244 #endif
245 3 }
246
247 3 static int set_volume(AVFilterContext *ctx)
248 {
249 3 VolumeContext *vol = ctx->priv;
250
251 3 vol->volume = av_expr_eval(vol->volume_pexpr, vol->var_values, NULL);
252
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3 if (isnan(vol->volume)) {
253 if (vol->eval_mode == EVAL_MODE_ONCE) {
254 av_log(ctx, AV_LOG_ERROR, "Invalid value NaN for volume\n");
255 return AVERROR(EINVAL);
256 } else {
257 av_log(ctx, AV_LOG_WARNING, "Invalid value NaN for volume, setting to 0\n");
258 vol->volume = 0;
259 }
260 }
261 3 vol->var_values[VAR_VOLUME] = vol->volume;
262
263 3 av_log(ctx, AV_LOG_VERBOSE, "n:%f t:%f pts:%f precision:%s ",
264 vol->var_values[VAR_N], vol->var_values[VAR_T], vol->var_values[VAR_PTS],
265 3 precision_str[vol->precision]);
266
267
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3 if (vol->precision == PRECISION_FIXED) {
268 2 vol->volume_i = (int)(vol->volume * 256 + 0.5);
269 2 vol->volume = vol->volume_i / 256.0;
270 2 av_log(ctx, AV_LOG_VERBOSE, "volume_i:%d/255 ", vol->volume_i);
271 }
272 3 av_log(ctx, AV_LOG_VERBOSE, "volume:%f volume_dB:%f\n",
273 3 vol->volume, 20.0*log10(vol->volume));
274
275 3 volume_init(vol);
276 3 return 0;
277 }
278
279 3 static int config_output(AVFilterLink *outlink)
280 {
281 3 AVFilterContext *ctx = outlink->src;
282 3 VolumeContext *vol = ctx->priv;
283 3 AVFilterLink *inlink = ctx->inputs[0];
284
285 3 vol->sample_fmt = inlink->format;
286 3 vol->channels = inlink->ch_layout.nb_channels;
287
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3 vol->planes = av_sample_fmt_is_planar(inlink->format) ? vol->channels : 1;
288
289 3 vol->var_values[VAR_N] =
290 3 vol->var_values[VAR_NB_CONSUMED_SAMPLES] =
291 3 vol->var_values[VAR_NB_SAMPLES] =
292 #if FF_API_FRAME_PKT
293 3 vol->var_values[VAR_POS] =
294 #endif
295 3 vol->var_values[VAR_PTS] =
296 3 vol->var_values[VAR_STARTPTS] =
297 3 vol->var_values[VAR_STARTT] =
298 3 vol->var_values[VAR_T] =
299 3 vol->var_values[VAR_VOLUME] = NAN;
300
301 3 vol->var_values[VAR_NB_CHANNELS] = inlink->ch_layout.nb_channels;
302 3 vol->var_values[VAR_TB] = av_q2d(inlink->time_base);
303 3 vol->var_values[VAR_SAMPLE_RATE] = inlink->sample_rate;
304
305 3 av_log(inlink->src, AV_LOG_VERBOSE, "tb:%f sample_rate:%f nb_channels:%f\n",
306 vol->var_values[VAR_TB],
307 vol->var_values[VAR_SAMPLE_RATE],
308 vol->var_values[VAR_NB_CHANNELS]);
309
310 3 return set_volume(ctx);
311 }
312
313 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
314 char *res, int res_len, int flags)
315 {
316 VolumeContext *vol = ctx->priv;
317 int ret = AVERROR(ENOSYS);
318
319 if (!strcmp(cmd, "volume")) {
320 if ((ret = set_expr(&vol->volume_pexpr, args, ctx)) < 0)
321 return ret;
322 if (vol->eval_mode == EVAL_MODE_ONCE)
323 set_volume(ctx);
324 }
325
326 return ret;
327 }
328
329 199 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
330 {
331 199 AVFilterContext *ctx = inlink->dst;
332 199 VolumeContext *vol = inlink->dst->priv;
333 199 AVFilterLink *outlink = inlink->dst->outputs[0];
334 199 int nb_samples = buf->nb_samples;
335 AVFrame *out_buf;
336 199 AVFrameSideData *sd = av_frame_get_side_data(buf, AV_FRAME_DATA_REPLAYGAIN);
337 int ret;
338
339
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199 if (sd && vol->replaygain != REPLAYGAIN_IGNORE) {
340 if (vol->replaygain != REPLAYGAIN_DROP) {
341 AVReplayGain *replaygain = (AVReplayGain*)sd->data;
342 int32_t gain = 100000;
343 uint32_t peak = 100000;
344 float g, p;
345
346 if (vol->replaygain == REPLAYGAIN_TRACK &&
347 replaygain->track_gain != INT32_MIN) {
348 gain = replaygain->track_gain;
349
350 if (replaygain->track_peak != 0)
351 peak = replaygain->track_peak;
352 } else if (replaygain->album_gain != INT32_MIN) {
353 gain = replaygain->album_gain;
354
355 if (replaygain->album_peak != 0)
356 peak = replaygain->album_peak;
357 } else {
358 av_log(inlink->dst, AV_LOG_WARNING, "Both ReplayGain gain "
359 "values are unknown.\n");
360 }
361 g = gain / 100000.0f;
362 p = peak / 100000.0f;
363
364 av_log(inlink->dst, AV_LOG_VERBOSE,
365 "Using gain %f dB from replaygain side data.\n", g);
366
367 vol->volume = ff_exp10((g + vol->replaygain_preamp) / 20);
368 if (vol->replaygain_noclip)
369 vol->volume = FFMIN(vol->volume, 1.0 / p);
370 vol->volume_i = (int)(vol->volume * 256 + 0.5);
371
372 volume_init(vol);
373 }
374 av_frame_remove_side_data(buf, AV_FRAME_DATA_REPLAYGAIN);
375 }
376
377
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199 if (isnan(vol->var_values[VAR_STARTPTS])) {
378
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3 vol->var_values[VAR_STARTPTS] = TS2D(buf->pts);
379
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3 vol->var_values[VAR_STARTT ] = TS2T(buf->pts, inlink->time_base);
380 }
381
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199 vol->var_values[VAR_PTS] = TS2D(buf->pts);
382
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199 vol->var_values[VAR_T ] = TS2T(buf->pts, inlink->time_base);
383 199 vol->var_values[VAR_N ] = inlink->frame_count_out;
384
385 #if FF_API_FRAME_PKT
386 FF_DISABLE_DEPRECATION_WARNINGS
387 {
388 int64_t pos;
389 199 pos = buf->pkt_pos;
390
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199 vol->var_values[VAR_POS] = pos == -1 ? NAN : pos;
391 }
392 FF_ENABLE_DEPRECATION_WARNINGS
393 #endif
394
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199 if (vol->eval_mode == EVAL_MODE_FRAME)
395 set_volume(ctx);
396
397
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199 if (vol->volume == 1.0 || vol->volume_i == 256) {
398 out_buf = buf;
399 goto end;
400 }
401
402 /* do volume scaling in-place if input buffer is writable */
403
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199 if (av_frame_is_writable(buf)
404
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199 && (vol->precision != PRECISION_FIXED || vol->volume_i > 0)) {
405 106 out_buf = buf;
406 } else {
407 93 out_buf = ff_get_audio_buffer(outlink, nb_samples);
408
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93 if (!out_buf) {
409 av_frame_free(&buf);
410 return AVERROR(ENOMEM);
411 }
412 93 ret = av_frame_copy_props(out_buf, buf);
413
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93 if (ret < 0) {
414 av_frame_free(&out_buf);
415 av_frame_free(&buf);
416 return ret;
417 }
418 }
419
420
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199 if (vol->precision != PRECISION_FIXED || vol->volume_i > 0) {
421 int p, plane_samples;
422
423
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106 if (av_sample_fmt_is_planar(buf->format))
424 41 plane_samples = FFALIGN(nb_samples, vol->samples_align);
425 else
426 65 plane_samples = FFALIGN(nb_samples * vol->channels, vol->samples_align);
427
428
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106 if (vol->precision == PRECISION_FIXED) {
429
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130 for (p = 0; p < vol->planes; p++) {
430 65 vol->scale_samples(out_buf->extended_data[p],
431 65 buf->extended_data[p], plane_samples,
432 vol->volume_i);
433 }
434
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41 } else if (av_get_packed_sample_fmt(vol->sample_fmt) == AV_SAMPLE_FMT_FLT) {
435
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123 for (p = 0; p < vol->planes; p++) {
436 82 vol->fdsp->vector_fmul_scalar((float *)out_buf->extended_data[p],
437 82 (const float *)buf->extended_data[p],
438 82 vol->volume, plane_samples);
439 }
440 } else {
441 for (p = 0; p < vol->planes; p++) {
442 vol->fdsp->vector_dmul_scalar((double *)out_buf->extended_data[p],
443 (const double *)buf->extended_data[p],
444 vol->volume, plane_samples);
445 }
446 }
447 }
448
449
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199 if (buf != out_buf)
450 93 av_frame_free(&buf);
451
452 106 end:
453 199 vol->var_values[VAR_NB_CONSUMED_SAMPLES] += out_buf->nb_samples;
454 199 return ff_filter_frame(outlink, out_buf);
455 }
456
457 static const AVFilterPad avfilter_af_volume_inputs[] = {
458 {
459 .name = "default",
460 .type = AVMEDIA_TYPE_AUDIO,
461 .filter_frame = filter_frame,
462 },
463 };
464
465 static const AVFilterPad avfilter_af_volume_outputs[] = {
466 {
467 .name = "default",
468 .type = AVMEDIA_TYPE_AUDIO,
469 .config_props = config_output,
470 },
471 };
472
473 const AVFilter ff_af_volume = {
474 .name = "volume",
475 .description = NULL_IF_CONFIG_SMALL("Change input volume."),
476 .priv_size = sizeof(VolumeContext),
477 .priv_class = &volume_class,
478 .init = init,
479 .uninit = uninit,
480 FILTER_INPUTS(avfilter_af_volume_inputs),
481 FILTER_OUTPUTS(avfilter_af_volume_outputs),
482 FILTER_QUERY_FUNC(query_formats),
483 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
484 .process_command = process_command,
485 };
486