FFmpeg coverage

GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavfilter/af_silenceremove.c	Lines:	186	333	55.9 %
Date:	2021-04-15 16:04:23	Branches:	54	145	37.2 %


/*
 * Copyright (c) 2001 Heikki Leinonen
 * Copyright (c) 2001 Chris Bagwell
 * Copyright (c) 2003 Donnie Smith
 * Copyright (c) 2014 Paul B Mahol
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <float.h> /* DBL_MAX */

#include "libavutil/opt.h"
#include "libavutil/timestamp.h"
#include "audio.h"
#include "formats.h"
#include "avfilter.h"
#include "internal.h"

enum SilenceDetect {
    D_PEAK,
    D_RMS,
};

enum ThresholdMode {
    T_ANY,
    T_ALL,
};

enum SilenceMode {
    SILENCE_TRIM,
    SILENCE_TRIM_FLUSH,
    SILENCE_COPY,
    SILENCE_COPY_FLUSH,
    SILENCE_STOP
};

typedef struct SilenceRemoveContext {
    const AVClass *class;

    enum SilenceMode mode;

    int start_periods;
    int64_t start_duration;
    int64_t start_duration_opt;
    double start_threshold;
    int64_t start_silence;
    int64_t start_silence_opt;
    int start_mode;

    int stop_periods;
    int64_t stop_duration;
    int64_t stop_duration_opt;
    double stop_threshold;
    int64_t stop_silence;
    int64_t stop_silence_opt;
    int stop_mode;

    double *start_holdoff;
    double *start_silence_hold;
    size_t start_holdoff_offset;
    size_t start_holdoff_end;
    size_t start_silence_offset;
    size_t start_silence_end;
    int    start_found_periods;

    double *stop_holdoff;
    double *stop_silence_hold;
    size_t stop_holdoff_offset;
    size_t stop_holdoff_end;
    size_t stop_silence_offset;
    size_t stop_silence_end;
    int    stop_found_periods;

    double window_ratio;
    double *window;
    double *window_current;
    double *window_end;
    int window_size;
    double sum;

    int restart;
    int64_t next_pts;

    int detection;
    void (*update)(struct SilenceRemoveContext *s, double sample);
    double(*compute)(struct SilenceRemoveContext *s, double sample);
} SilenceRemoveContext;

#define OFFSET(x) offsetof(SilenceRemoveContext, x)
#define AF AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_AUDIO_PARAM

static const AVOption silenceremove_options[] = {
    { "start_periods",   NULL,                                                 OFFSET(start_periods),       AV_OPT_TYPE_INT,      {.i64=0},     0,      9000, AF },
    { "start_duration",  "set start duration of non-silence part",             OFFSET(start_duration_opt),  AV_OPT_TYPE_DURATION, {.i64=0},     0, INT32_MAX, AF },
    { "start_threshold", "set threshold for start silence detection",          OFFSET(start_threshold),     AV_OPT_TYPE_DOUBLE,   {.dbl=0},     0,   DBL_MAX, AF },
    { "start_silence",   "set start duration of silence part to keep",         OFFSET(start_silence_opt),   AV_OPT_TYPE_DURATION, {.i64=0},     0, INT32_MAX, AF },
    { "start_mode",      "set which channel will trigger trimming from start", OFFSET(start_mode),          AV_OPT_TYPE_INT,      {.i64=T_ANY}, T_ANY, T_ALL, AF, "mode" },
    {   "any",           0,                                                    0,                           AV_OPT_TYPE_CONST,    {.i64=T_ANY}, 0,         0, AF, "mode" },
    {   "all",           0,                                                    0,                           AV_OPT_TYPE_CONST,    {.i64=T_ALL}, 0,         0, AF, "mode" },
    { "stop_periods",    NULL,                                                 OFFSET(stop_periods),        AV_OPT_TYPE_INT,      {.i64=0}, -9000,      9000, AF },
    { "stop_duration",   "set stop duration of non-silence part",              OFFSET(stop_duration_opt),   AV_OPT_TYPE_DURATION, {.i64=0},     0, INT32_MAX, AF },
    { "stop_threshold",  "set threshold for stop silence detection",           OFFSET(stop_threshold),      AV_OPT_TYPE_DOUBLE,   {.dbl=0},     0,   DBL_MAX, AF },
    { "stop_silence",    "set stop duration of silence part to keep",          OFFSET(stop_silence_opt),    AV_OPT_TYPE_DURATION, {.i64=0},     0, INT32_MAX, AF },
    { "stop_mode",       "set which channel will trigger trimming from end",   OFFSET(stop_mode),           AV_OPT_TYPE_INT,      {.i64=T_ANY}, T_ANY, T_ALL, AF, "mode" },
    { "detection",       "set how silence is detected",                        OFFSET(detection),           AV_OPT_TYPE_INT,      {.i64=D_RMS}, D_PEAK,D_RMS, AF, "detection" },
    {   "peak",          "use absolute values of samples",                     0,                           AV_OPT_TYPE_CONST,    {.i64=D_PEAK},0,         0, AF, "detection" },
    {   "rms",           "use squared values of samples",                      0,                           AV_OPT_TYPE_CONST,    {.i64=D_RMS}, 0,         0, AF, "detection" },
    { "window",          "set duration of window in seconds",                  OFFSET(window_ratio),        AV_OPT_TYPE_DOUBLE,   {.dbl=0.02},  0,        10, AF },
    { NULL }
};

AVFILTER_DEFINE_CLASS(silenceremove);

static double compute_peak(SilenceRemoveContext *s, double sample)
{
    double new_sum;

    new_sum  = s->sum;
    new_sum -= *s->window_current;
    new_sum += fabs(sample);

    return new_sum / s->window_size;
}

static void update_peak(SilenceRemoveContext *s, double sample)
{
    s->sum -= *s->window_current;
    *s->window_current = fabs(sample);
    s->sum += *s->window_current;

    s->window_current++;
    if (s->window_current >= s->window_end)
        s->window_current = s->window;
}

static double compute_rms(SilenceRemoveContext *s, double sample)
{
    double new_sum;

    new_sum  = s->sum;
    new_sum -= *s->window_current;
    new_sum += sample * sample;

    return sqrt(new_sum / s->window_size);
}

static void update_rms(SilenceRemoveContext *s, double sample)
{
    s->sum -= *s->window_current;
    *s->window_current = sample * sample;
    s->sum += *s->window_current;

    s->window_current++;
    if (s->window_current >= s->window_end)
        s->window_current = s->window;
}

static av_cold int init(AVFilterContext *ctx)
{
    SilenceRemoveContext *s = ctx->priv;

    if (s->stop_periods < 0) {
        s->stop_periods = -s->stop_periods;
        s->restart = 1;
    }

    switch (s->detection) {
    case D_PEAK:
        s->update = update_peak;
        s->compute = compute_peak;
        break;
    case D_RMS:
        s->update = update_rms;
        s->compute = compute_rms;
        break;
    }

    return 0;
}

static void clear_window(SilenceRemoveContext *s)
{
    memset(s->window, 0, s->window_size * sizeof(*s->window));

    s->window_current = s->window;
    s->window_end = s->window + s->window_size;
    s->sum = 0;
}

static int config_input(AVFilterLink *inlink)
{
    AVFilterContext *ctx = inlink->dst;
    SilenceRemoveContext *s = ctx->priv;

    s->next_pts = AV_NOPTS_VALUE;
    s->window_size = FFMAX((inlink->sample_rate * s->window_ratio), 1) * inlink->channels;
    s->window = av_malloc_array(s->window_size, sizeof(*s->window));
    if (!s->window)
        return AVERROR(ENOMEM);

    clear_window(s);

    s->start_duration = av_rescale(s->start_duration_opt, inlink->sample_rate,
                                   AV_TIME_BASE);
    s->start_silence  = av_rescale(s->start_silence_opt, inlink->sample_rate,
                                   AV_TIME_BASE);
    s->stop_duration  = av_rescale(s->stop_duration_opt, inlink->sample_rate,
                                   AV_TIME_BASE);
    s->stop_silence   = av_rescale(s->stop_silence_opt, inlink->sample_rate,
                                   AV_TIME_BASE);

    s->start_holdoff = av_malloc_array(FFMAX(s->start_duration, 1),
                                       sizeof(*s->start_holdoff) *
                                       inlink->channels);
    if (!s->start_holdoff)
        return AVERROR(ENOMEM);

    s->start_silence_hold = av_malloc_array(FFMAX(s->start_silence, 1),
                                            sizeof(*s->start_silence_hold) *
                                            inlink->channels);
    if (!s->start_silence_hold)
        return AVERROR(ENOMEM);

    s->start_holdoff_offset = 0;
    s->start_holdoff_end    = 0;
    s->start_found_periods  = 0;

    s->stop_holdoff = av_malloc_array(FFMAX(s->stop_duration, 1),
                                      sizeof(*s->stop_holdoff) *
                                      inlink->channels);
    if (!s->stop_holdoff)
        return AVERROR(ENOMEM);

    s->stop_silence_hold = av_malloc_array(FFMAX(s->stop_silence, 1),
                                           sizeof(*s->stop_silence_hold) *
                                           inlink->channels);
    if (!s->stop_silence_hold)
        return AVERROR(ENOMEM);

    s->stop_holdoff_offset = 0;
    s->stop_holdoff_end    = 0;
    s->stop_found_periods  = 0;

    if (s->start_periods)
        s->mode = SILENCE_TRIM;
    else
        s->mode = SILENCE_COPY;

    return 0;
}

static void flush(SilenceRemoveContext *s,
                  AVFrame *out, AVFilterLink *outlink,
                  int *nb_samples_written, int *ret, int flush_silence)
{
    AVFrame *silence;

    if (*nb_samples_written) {
        out->nb_samples = *nb_samples_written / outlink->channels;

        out->pts = s->next_pts;
        s->next_pts += av_rescale_q(out->nb_samples,
                                    (AVRational){1, outlink->sample_rate},
                                    outlink->time_base);

        *ret = ff_filter_frame(outlink, out);
        if (*ret < 0)
            return;
        *nb_samples_written = 0;
    } else {
        av_frame_free(&out);
    }

    if (s->stop_silence_end <= 0 || !flush_silence)
        return;

    silence = ff_get_audio_buffer(outlink, s->stop_silence_end / outlink->channels);
    if (!silence) {
        *ret = AVERROR(ENOMEM);
        return;
    }

    if (s->stop_silence_offset < s->stop_silence_end) {
        memcpy(silence->data[0],
               &s->stop_silence_hold[s->stop_silence_offset],
               (s->stop_silence_end - s->stop_silence_offset) * sizeof(double));
    }

    if (s->stop_silence_offset > 0) {
        memcpy(silence->data[0] + (s->stop_silence_end - s->stop_silence_offset) * sizeof(double),
               &s->stop_silence_hold[0],
               s->stop_silence_offset * sizeof(double));
    }

    s->stop_silence_offset = 0;
    s->stop_silence_end = 0;

    silence->pts = s->next_pts;
    s->next_pts += av_rescale_q(silence->nb_samples,
                                (AVRational){1, outlink->sample_rate},
                                outlink->time_base);

    *ret = ff_filter_frame(outlink, silence);
}

static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
    AVFilterContext *ctx = inlink->dst;
    AVFilterLink *outlink = ctx->outputs[0];
    SilenceRemoveContext *s = ctx->priv;
    int i, j, threshold, ret = 0;
    int nbs, nb_samples_read, nb_samples_written;
    double *obuf, *ibuf = (double *)in->data[0];
    AVFrame *out;

    nb_samples_read = nb_samples_written = 0;

    if (s->next_pts == AV_NOPTS_VALUE)
        s->next_pts = in->pts;

    switch (s->mode) {
    case SILENCE_TRIM:
silence_trim:
        nbs = in->nb_samples - nb_samples_read / outlink->channels;
        if (!nbs)
            break;

        for (i = 0; i < nbs; i++) {
            if (s->start_mode == T_ANY) {
                threshold = 0;
                for (j = 0; j < outlink->channels; j++) {
                    threshold |= s->compute(s, ibuf[j]) > s->start_threshold;
                }
            } else {
                threshold = 1;
                for (j = 0; j < outlink->channels; j++) {
                    threshold &= s->compute(s, ibuf[j]) > s->start_threshold;
                }
            }

            if (threshold) {
                for (j = 0; j < outlink->channels; j++) {
                    s->update(s, *ibuf);
                    s->start_holdoff[s->start_holdoff_end++] = *ibuf++;
                }
                nb_samples_read += outlink->channels;

                if (s->start_holdoff_end >= s->start_duration * outlink->channels) {
                    if (++s->start_found_periods >= s->start_periods) {
                        s->mode = SILENCE_TRIM_FLUSH;
                        goto silence_trim_flush;
                    }

                    s->start_holdoff_offset = 0;
                    s->start_holdoff_end = 0;
                    s->start_silence_offset = 0;
                    s->start_silence_end = 0;
                }
            } else {
                s->start_holdoff_end = 0;

                for (j = 0; j < outlink->channels; j++) {
                    s->update(s, ibuf[j]);
                    if (s->start_silence) {
                        s->start_silence_hold[s->start_silence_offset++] = ibuf[j];
                        s->start_silence_end = FFMIN(s->start_silence_end + 1, outlink->channels * s->start_silence);
                        if (s->start_silence_offset >= outlink->channels * s->start_silence) {
                            s->start_silence_offset = 0;
                        }
                    }
                }

                ibuf += outlink->channels;
                nb_samples_read += outlink->channels;
            }
        }
        break;

    case SILENCE_TRIM_FLUSH:
silence_trim_flush:
        nbs  = s->start_holdoff_end - s->start_holdoff_offset;
        nbs -= nbs % outlink->channels;
        if (!nbs)
            break;

        out = ff_get_audio_buffer(outlink, nbs / outlink->channels + s->start_silence_end / outlink->channels);
        if (!out) {
            av_frame_free(&in);
            return AVERROR(ENOMEM);
        }

        if (s->start_silence_end > 0) {
            if (s->start_silence_offset < s->start_silence_end) {
                memcpy(out->data[0],
                       &s->start_silence_hold[s->start_silence_offset],
                       (s->start_silence_end - s->start_silence_offset) * sizeof(double));
            }

            if (s->start_silence_offset > 0) {
                memcpy(out->data[0] + (s->start_silence_end - s->start_silence_offset) * sizeof(double),
                       &s->start_silence_hold[0],
                       s->start_silence_offset * sizeof(double));
            }
        }

        memcpy(out->data[0] + s->start_silence_end * sizeof(double),
               &s->start_holdoff[s->start_holdoff_offset],
               nbs * sizeof(double));

        out->pts = s->next_pts;
        s->next_pts += av_rescale_q(out->nb_samples,
                                    (AVRational){1, outlink->sample_rate},
                                    outlink->time_base);

        s->start_holdoff_offset += nbs;

        ret = ff_filter_frame(outlink, out);

        if (s->start_holdoff_offset == s->start_holdoff_end) {
            s->start_holdoff_offset = 0;
            s->start_holdoff_end = 0;
            s->start_silence_offset = 0;
            s->start_silence_end = 0;
            s->mode = SILENCE_COPY;
            goto silence_copy;
        }
        break;

    case SILENCE_COPY:
silence_copy:
        nbs = in->nb_samples - nb_samples_read / outlink->channels;
        if (!nbs)
            break;

        out = ff_get_audio_buffer(outlink, nbs);
        if (!out) {
            av_frame_free(&in);
            return AVERROR(ENOMEM);
        }
        obuf = (double *)out->data[0];

        if (s->stop_periods) {
            for (i = 0; i < nbs; i++) {
                if (s->stop_mode == T_ANY) {
                    threshold = 0;
                    for (j = 0; j < outlink->channels; j++) {
                        threshold |= s->compute(s, ibuf[j]) > s->stop_threshold;
                    }
                } else {
                    threshold = 1;
                    for (j = 0; j < outlink->channels; j++) {
                        threshold &= s->compute(s, ibuf[j]) > s->stop_threshold;
                    }
                }

                if (threshold && s->stop_holdoff_end && !s->stop_silence) {
                    s->mode = SILENCE_COPY_FLUSH;
                    flush(s, out, outlink, &nb_samples_written, &ret, 0);
                    goto silence_copy_flush;
                } else if (threshold) {
                    for (j = 0; j < outlink->channels; j++) {
                        s->update(s, *ibuf);
                        *obuf++ = *ibuf++;
                    }
                    nb_samples_read    += outlink->channels;
                    nb_samples_written += outlink->channels;
                } else if (!threshold) {
                    for (j = 0; j < outlink->channels; j++) {
                        s->update(s, *ibuf);
                        if (s->stop_silence) {
                            s->stop_silence_hold[s->stop_silence_offset++] = *ibuf;
                            s->stop_silence_end = FFMIN(s->stop_silence_end + 1, outlink->channels * s->stop_silence);
                            if (s->stop_silence_offset >= outlink->channels * s->stop_silence) {
                                s->stop_silence_offset = 0;
                            }
                        }

                        s->stop_holdoff[s->stop_holdoff_end++] = *ibuf++;
                    }
                    nb_samples_read += outlink->channels;

                    if (s->stop_holdoff_end >= s->stop_duration * outlink->channels) {
                        if (++s->stop_found_periods >= s->stop_periods) {
                            s->stop_holdoff_offset = 0;
                            s->stop_holdoff_end = 0;

                            if (!s->restart) {
                                s->mode = SILENCE_STOP;
                                flush(s, out, outlink, &nb_samples_written, &ret, 1);
                                goto silence_stop;
                            } else {
                                s->stop_found_periods = 0;
                                s->start_found_periods = 0;
                                s->start_holdoff_offset = 0;
                                s->start_holdoff_end = 0;
                                s->start_silence_offset = 0;
                                s->start_silence_end = 0;
                                clear_window(s);
                                s->mode = SILENCE_TRIM;
                                flush(s, out, outlink, &nb_samples_written, &ret, 1);
                                goto silence_trim;
                            }
                        }
                        s->mode = SILENCE_COPY_FLUSH;
                        flush(s, out, outlink, &nb_samples_written, &ret, 0);
                        goto silence_copy_flush;
                    }
                }
            }
            flush(s, out, outlink, &nb_samples_written, &ret, 0);
        } else {
            memcpy(obuf, ibuf, sizeof(double) * nbs * outlink->channels);

            out->pts = s->next_pts;
            s->next_pts += av_rescale_q(out->nb_samples,
                                        (AVRational){1, outlink->sample_rate},
                                        outlink->time_base);

            ret = ff_filter_frame(outlink, out);
        }
        break;

    case SILENCE_COPY_FLUSH:
silence_copy_flush:
        nbs  = s->stop_holdoff_end - s->stop_holdoff_offset;
        nbs -= nbs % outlink->channels;
        if (!nbs)
            break;

        out = ff_get_audio_buffer(outlink, nbs / outlink->channels);
        if (!out) {
            av_frame_free(&in);
            return AVERROR(ENOMEM);
        }

        memcpy(out->data[0], &s->stop_holdoff[s->stop_holdoff_offset],
               nbs * sizeof(double));
        s->stop_holdoff_offset += nbs;

        out->pts = s->next_pts;
        s->next_pts += av_rescale_q(out->nb_samples,
                                    (AVRational){1, outlink->sample_rate},
                                    outlink->time_base);

        ret = ff_filter_frame(outlink, out);

        if (s->stop_holdoff_offset == s->stop_holdoff_end) {
            s->stop_holdoff_offset = 0;
            s->stop_holdoff_end = 0;
            s->stop_silence_offset = 0;
            s->stop_silence_end = 0;
            s->mode = SILENCE_COPY;
            goto silence_copy;
        }
        break;
    case SILENCE_STOP:
silence_stop:
        break;
    }

    av_frame_free(&in);

    return ret;
}

static int request_frame(AVFilterLink *outlink)
{
    AVFilterContext *ctx = outlink->src;
    SilenceRemoveContext *s = ctx->priv;
    int ret;

    ret = ff_request_frame(ctx->inputs[0]);
    if (ret == AVERROR_EOF && (s->mode == SILENCE_COPY_FLUSH ||
                               s->mode == SILENCE_COPY)) {
        int nbs = s->stop_holdoff_end - s->stop_holdoff_offset;
        if (nbs) {
            AVFrame *frame;

            frame = ff_get_audio_buffer(outlink, nbs / outlink->channels);
            if (!frame)
                return AVERROR(ENOMEM);

            memcpy(frame->data[0], &s->stop_holdoff[s->stop_holdoff_offset],
                   nbs * sizeof(double));

            frame->pts = s->next_pts;
            s->next_pts += av_rescale_q(frame->nb_samples,
                                        (AVRational){1, outlink->sample_rate},
                                        outlink->time_base);

            ret = ff_filter_frame(outlink, frame);
        }
        s->mode = SILENCE_STOP;
    }
    return ret;
}

static int query_formats(AVFilterContext *ctx)
{
    AVFilterFormats *formats = NULL;
    AVFilterChannelLayouts *layouts = NULL;
    static const enum AVSampleFormat sample_fmts[] = {
        AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_NONE
    };
    int ret;

    layouts = ff_all_channel_counts();
    if (!layouts)
        return AVERROR(ENOMEM);
    ret = ff_set_common_channel_layouts(ctx, layouts);
    if (ret < 0)
        return ret;

    formats = ff_make_format_list(sample_fmts);
    if (!formats)
        return AVERROR(ENOMEM);
    ret = ff_set_common_formats(ctx, formats);
    if (ret < 0)
        return ret;

    formats = ff_all_samplerates();
    if (!formats)
        return AVERROR(ENOMEM);
    return ff_set_common_samplerates(ctx, formats);
}

static av_cold void uninit(AVFilterContext *ctx)
{
    SilenceRemoveContext *s = ctx->priv;

    av_freep(&s->start_holdoff);
    av_freep(&s->start_silence_hold);
    av_freep(&s->stop_holdoff);
    av_freep(&s->stop_silence_hold);
    av_freep(&s->window);
}

static const AVFilterPad silenceremove_inputs[] = {
    {
        .name         = "default",
        .type         = AVMEDIA_TYPE_AUDIO,
        .config_props = config_input,
        .filter_frame = filter_frame,
    },
    { NULL }
};

static const AVFilterPad silenceremove_outputs[] = {
    {
        .name          = "default",
        .type          = AVMEDIA_TYPE_AUDIO,
        .request_frame = request_frame,
    },
    { NULL }
};

AVFilter ff_af_silenceremove = {
    .name          = "silenceremove",
    .description   = NULL_IF_CONFIG_SMALL("Remove silence."),
    .priv_size     = sizeof(SilenceRemoveContext),
    .priv_class    = &silenceremove_class,
    .init          = init,
    .uninit        = uninit,
    .query_formats = query_formats,
    .inputs        = silenceremove_inputs,
    .outputs       = silenceremove_outputs,
};


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			/*
2			* Copyright (c) 2001 Heikki Leinonen
3			* Copyright (c) 2001 Chris Bagwell
4			* Copyright (c) 2003 Donnie Smith
5			* Copyright (c) 2014 Paul B Mahol
6			*
7			* This file is part of FFmpeg.
8			*
9			* FFmpeg is free software; you can redistribute it and/or
10			* modify it under the terms of the GNU Lesser General Public
11			* License as published by the Free Software Foundation; either
12			* version 2.1 of the License, or (at your option) any later version.
13			*
14			* FFmpeg is distributed in the hope that it will be useful,
15			* but WITHOUT ANY WARRANTY; without even the implied warranty of
16			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17			* Lesser General Public License for more details.
18			*
19			* You should have received a copy of the GNU Lesser General Public
20			* License along with FFmpeg; if not, write to the Free Software
21			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22			*/
23
24			#include <float.h> /* DBL_MAX */
25
26			#include "libavutil/opt.h"
27			#include "libavutil/timestamp.h"
28			#include "audio.h"
29			#include "formats.h"
30			#include "avfilter.h"
31			#include "internal.h"
32
33			enum SilenceDetect {
34			D_PEAK,
35			D_RMS,
36			};
37
38			enum ThresholdMode {
39			T_ANY,
40			T_ALL,
41			};
42
43			enum SilenceMode {
44			SILENCE_TRIM,
45			SILENCE_TRIM_FLUSH,
46			SILENCE_COPY,
47			SILENCE_COPY_FLUSH,
48			SILENCE_STOP
49			};
50
51			typedef struct SilenceRemoveContext {
52			const AVClass *class;
53
54			enum SilenceMode mode;
55
56			int start_periods;
57			int64_t start_duration;
58			int64_t start_duration_opt;
59			double start_threshold;
60			int64_t start_silence;
61			int64_t start_silence_opt;
62			int start_mode;
63
64			int stop_periods;
65			int64_t stop_duration;
66			int64_t stop_duration_opt;
67			double stop_threshold;
68			int64_t stop_silence;
69			int64_t stop_silence_opt;
70			int stop_mode;
71
72			double *start_holdoff;
73			double *start_silence_hold;
74			size_t start_holdoff_offset;
75			size_t start_holdoff_end;
76			size_t start_silence_offset;
77			size_t start_silence_end;
78			int start_found_periods;
79
80			double *stop_holdoff;
81			double *stop_silence_hold;
82			size_t stop_holdoff_offset;
83			size_t stop_holdoff_end;
84			size_t stop_silence_offset;
85			size_t stop_silence_end;
86			int stop_found_periods;
87
88			double window_ratio;
89			double *window;
90			double *window_current;
91			double *window_end;
92			int window_size;
93			double sum;
94
95			int restart;
96			int64_t next_pts;
97
98			int detection;
99			void (update)(struct SilenceRemoveContext s, double sample);
100			double(compute)(struct SilenceRemoveContext s, double sample);
101			} SilenceRemoveContext;
102
103			#define OFFSET(x) offsetof(SilenceRemoveContext, x)
104			#define AF AV_OPT_FLAG_FILTERING_PARAM\|AV_OPT_FLAG_AUDIO_PARAM
105
106			static const AVOption silenceremove_options[] = {
107			{ "start_periods", NULL, OFFSET(start_periods), AV_OPT_TYPE_INT, {.i64=0}, 0, 9000, AF },
108			{ "start_duration", "set start duration of non-silence part", OFFSET(start_duration_opt), AV_OPT_TYPE_DURATION, {.i64=0}, 0, INT32_MAX, AF },
109			{ "start_threshold", "set threshold for start silence detection", OFFSET(start_threshold), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, DBL_MAX, AF },
110			{ "start_silence", "set start duration of silence part to keep", OFFSET(start_silence_opt), AV_OPT_TYPE_DURATION, {.i64=0}, 0, INT32_MAX, AF },
111			{ "start_mode", "set which channel will trigger trimming from start", OFFSET(start_mode), AV_OPT_TYPE_INT, {.i64=T_ANY}, T_ANY, T_ALL, AF, "mode" },
112			{ "any", 0, 0, AV_OPT_TYPE_CONST, {.i64=T_ANY}, 0, 0, AF, "mode" },
113			{ "all", 0, 0, AV_OPT_TYPE_CONST, {.i64=T_ALL}, 0, 0, AF, "mode" },
114			{ "stop_periods", NULL, OFFSET(stop_periods), AV_OPT_TYPE_INT, {.i64=0}, -9000, 9000, AF },
115			{ "stop_duration", "set stop duration of non-silence part", OFFSET(stop_duration_opt), AV_OPT_TYPE_DURATION, {.i64=0}, 0, INT32_MAX, AF },
116			{ "stop_threshold", "set threshold for stop silence detection", OFFSET(stop_threshold), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, DBL_MAX, AF },
117			{ "stop_silence", "set stop duration of silence part to keep", OFFSET(stop_silence_opt), AV_OPT_TYPE_DURATION, {.i64=0}, 0, INT32_MAX, AF },
118			{ "stop_mode", "set which channel will trigger trimming from end", OFFSET(stop_mode), AV_OPT_TYPE_INT, {.i64=T_ANY}, T_ANY, T_ALL, AF, "mode" },
119			{ "detection", "set how silence is detected", OFFSET(detection), AV_OPT_TYPE_INT, {.i64=D_RMS}, D_PEAK,D_RMS, AF, "detection" },
120			{ "peak", "use absolute values of samples", 0, AV_OPT_TYPE_CONST, {.i64=D_PEAK},0, 0, AF, "detection" },
121			{ "rms", "use squared values of samples", 0, AV_OPT_TYPE_CONST, {.i64=D_RMS}, 0, 0, AF, "detection" },
122			{ "window", "set duration of window in seconds", OFFSET(window_ratio), AV_OPT_TYPE_DOUBLE, {.dbl=0.02}, 0, 10, AF },
123			{ NULL }
124			};
125
126			AVFILTER_DEFINE_CLASS(silenceremove);
127
128			static double compute_peak(SilenceRemoveContext *s, double sample)
129			{
130			double new_sum;
131
132			new_sum = s->sum;
133			new_sum -= *s->window_current;
134			new_sum += fabs(sample);
135
136			return new_sum / s->window_size;
137			}
138
139			static void update_peak(SilenceRemoveContext *s, double sample)
140			{
141			s->sum -= *s->window_current;
142			*s->window_current = fabs(sample);
143			s->sum += *s->window_current;
144
145			s->window_current++;
146			if (s->window_current >= s->window_end)
147			s->window_current = s->window;
148			}
149
150		1364	static double compute_rms(SilenceRemoveContext *s, double sample)
151			{
152			double new_sum;
153
154		1364	new_sum = s->sum;
155		1364	new_sum -= *s->window_current;
156		1364	new_sum += sample * sample;
157
158		1364	return sqrt(new_sum / s->window_size);
159			}
160
161		1364	static void update_rms(SilenceRemoveContext *s, double sample)
162			{
163		1364	s->sum -= *s->window_current;
164		1364	s->window_current = sample sample;
165		1364	s->sum += *s->window_current;
166
167		1364	s->window_current++;
168	✗✓	1364	if (s->window_current >= s->window_end)
169			s->window_current = s->window;
170		1364	}
171
172		1	static av_cold int init(AVFilterContext *ctx)
173			{
174		1	SilenceRemoveContext *s = ctx->priv;
175
176	✓✗	1	if (s->stop_periods < 0) {
177		1	s->stop_periods = -s->stop_periods;
178		1	s->restart = 1;
179			}
180
181	✗✓✗	1	switch (s->detection) {
182			case D_PEAK:
183			s->update = update_peak;
184			s->compute = compute_peak;
185			break;
186		1	case D_RMS:
187		1	s->update = update_rms;
188		1	s->compute = compute_rms;
189		1	break;
190			}
191
192		1	return 0;
193			}
194
195		342	static void clear_window(SilenceRemoveContext *s)
196			{
197		342	memset(s->window, 0, s->window_size * sizeof(*s->window));
198
199		342	s->window_current = s->window;
200		342	s->window_end = s->window + s->window_size;
201		342	s->sum = 0;
202		342	}
203
204		1	static int config_input(AVFilterLink *inlink)
205			{
206		1	AVFilterContext *ctx = inlink->dst;
207		1	SilenceRemoveContext *s = ctx->priv;
208
209		1	s->next_pts = AV_NOPTS_VALUE;
210	✓✗	1	s->window_size = FFMAX((inlink->sample_rate * s->window_ratio), 1) * inlink->channels;
211		1	s->window = av_malloc_array(s->window_size, sizeof(*s->window));
212	✗✓	1	if (!s->window)
213			return AVERROR(ENOMEM);
214
215		1	clear_window(s);
216
217		1	s->start_duration = av_rescale(s->start_duration_opt, inlink->sample_rate,
218			AV_TIME_BASE);
219		1	s->start_silence = av_rescale(s->start_silence_opt, inlink->sample_rate,
220			AV_TIME_BASE);
221		1	s->stop_duration = av_rescale(s->stop_duration_opt, inlink->sample_rate,
222			AV_TIME_BASE);
223		1	s->stop_silence = av_rescale(s->stop_silence_opt, inlink->sample_rate,
224			AV_TIME_BASE);
225
226		2	s->start_holdoff = av_malloc_array(FFMAX(s->start_duration, 1),
227			sizeof(s->start_holdoff)
228		1	inlink->channels);
229	✗✓	1	if (!s->start_holdoff)
230			return AVERROR(ENOMEM);
231
232		2	s->start_silence_hold = av_malloc_array(FFMAX(s->start_silence, 1),
233			sizeof(s->start_silence_hold)
234		1	inlink->channels);
235	✗✓	1	if (!s->start_silence_hold)
236			return AVERROR(ENOMEM);
237
238		1	s->start_holdoff_offset = 0;
239		1	s->start_holdoff_end = 0;
240		1	s->start_found_periods = 0;
241
242		2	s->stop_holdoff = av_malloc_array(FFMAX(s->stop_duration, 1),
243			sizeof(s->stop_holdoff)
244		1	inlink->channels);
245	✗✓	1	if (!s->stop_holdoff)
246			return AVERROR(ENOMEM);
247
248		2	s->stop_silence_hold = av_malloc_array(FFMAX(s->stop_silence, 1),
249			sizeof(s->stop_silence_hold)
250		1	inlink->channels);
251	✗✓	1	if (!s->stop_silence_hold)
252			return AVERROR(ENOMEM);
253
254		1	s->stop_holdoff_offset = 0;
255		1	s->stop_holdoff_end = 0;
256		1	s->stop_found_periods = 0;
257
258	✗✓	1	if (s->start_periods)
259			s->mode = SILENCE_TRIM;
260			else
261		1	s->mode = SILENCE_COPY;
262
263		1	return 0;
264			}
265
266		341	static void flush(SilenceRemoveContext *s,
267			AVFrame out, AVFilterLink outlink,
268			int nb_samples_written, int ret, int flush_silence)
269			{
270			AVFrame *silence;
271
272	✗✓	341	if (*nb_samples_written) {
273			out->nb_samples = *nb_samples_written / outlink->channels;
274
275			out->pts = s->next_pts;
276			s->next_pts += av_rescale_q(out->nb_samples,
277			(AVRational){1, outlink->sample_rate},
278			outlink->time_base);
279
280			*ret = ff_filter_frame(outlink, out);
281			if (*ret < 0)
282			return;
283			*nb_samples_written = 0;
284			} else {
285		341	av_frame_free(&out);
286			}
287
288	✗✓✗✗	341	if (s->stop_silence_end <= 0 \|\| !flush_silence)
289		341	return;
290
291			silence = ff_get_audio_buffer(outlink, s->stop_silence_end / outlink->channels);
292			if (!silence) {
293			*ret = AVERROR(ENOMEM);
294			return;
295			}
296
297			if (s->stop_silence_offset < s->stop_silence_end) {
298			memcpy(silence->data[0],
299			&s->stop_silence_hold[s->stop_silence_offset],
300			(s->stop_silence_end - s->stop_silence_offset) * sizeof(double));
301			}
302
303			if (s->stop_silence_offset > 0) {
304			memcpy(silence->data[0] + (s->stop_silence_end - s->stop_silence_offset) * sizeof(double),
305			&s->stop_silence_hold[0],
306			s->stop_silence_offset * sizeof(double));
307			}
308
309			s->stop_silence_offset = 0;
310			s->stop_silence_end = 0;
311
312			silence->pts = s->next_pts;
313			s->next_pts += av_rescale_q(silence->nb_samples,
314			(AVRational){1, outlink->sample_rate},
315			outlink->time_base);
316
317			*ret = ff_filter_frame(outlink, silence);
318			}
319
320		1	static int filter_frame(AVFilterLink inlink, AVFrame in)
321			{
322		1	AVFilterContext *ctx = inlink->dst;
323		1	AVFilterLink *outlink = ctx->outputs[0];
324		1	SilenceRemoveContext *s = ctx->priv;
325		1	int i, j, threshold, ret = 0;
326			int nbs, nb_samples_read, nb_samples_written;
327		1	double obuf, ibuf = (double *)in->data[0];
328			AVFrame *out;
329
330		1	nb_samples_read = nb_samples_written = 0;
331
332	✓✗	1	if (s->next_pts == AV_NOPTS_VALUE)
333		1	s->next_pts = in->pts;
334
335	✗✗✓✗ ✗✗	1	switch (s->mode) {
336			case SILENCE_TRIM:
337		341	silence_trim:
338		341	nbs = in->nb_samples - nb_samples_read / outlink->channels;
339	✗✓	341	if (!nbs)
340		1	break;
341
342	✓✗	341	for (i = 0; i < nbs; i++) {
343	✓✗	341	if (s->start_mode == T_ANY) {
344		341	threshold = 0;
345	✓✓	1023	for (j = 0; j < outlink->channels; j++) {
346		682	threshold \|= s->compute(s, ibuf[j]) > s->start_threshold;
347			}
348			} else {
349			threshold = 1;
350			for (j = 0; j < outlink->channels; j++) {
351			threshold &= s->compute(s, ibuf[j]) > s->start_threshold;
352			}
353			}
354
355	✓✗	341	if (threshold) {
356	✓✓	1023	for (j = 0; j < outlink->channels; j++) {
357		682	s->update(s, *ibuf);
358		682	s->start_holdoff[s->start_holdoff_end++] = *ibuf++;
359			}
360		341	nb_samples_read += outlink->channels;
361
362	✓✗	341	if (s->start_holdoff_end >= s->start_duration * outlink->channels) {
363	✓✗	341	if (++s->start_found_periods >= s->start_periods) {
364		341	s->mode = SILENCE_TRIM_FLUSH;
365		341	goto silence_trim_flush;
366			}
367
368			s->start_holdoff_offset = 0;
369			s->start_holdoff_end = 0;
370			s->start_silence_offset = 0;
371			s->start_silence_end = 0;
372			}
373			} else {
374			s->start_holdoff_end = 0;
375
376			for (j = 0; j < outlink->channels; j++) {
377			s->update(s, ibuf[j]);
378			if (s->start_silence) {
379			s->start_silence_hold[s->start_silence_offset++] = ibuf[j];
380			s->start_silence_end = FFMIN(s->start_silence_end + 1, outlink->channels * s->start_silence);
381			if (s->start_silence_offset >= outlink->channels * s->start_silence) {
382			s->start_silence_offset = 0;
383			}
384			}
385			}
386
387			ibuf += outlink->channels;
388			nb_samples_read += outlink->channels;
389			}
390			}
391			break;
392
393			case SILENCE_TRIM_FLUSH:
394		341	silence_trim_flush:
395		341	nbs = s->start_holdoff_end - s->start_holdoff_offset;
396		341	nbs -= nbs % outlink->channels;
397	✗✓	341	if (!nbs)
398			break;
399
400		341	out = ff_get_audio_buffer(outlink, nbs / outlink->channels + s->start_silence_end / outlink->channels);
401	✗✓	341	if (!out) {
402			av_frame_free(&in);
403			return AVERROR(ENOMEM);
404			}
405
406	✗✓	341	if (s->start_silence_end > 0) {
407			if (s->start_silence_offset < s->start_silence_end) {
408			memcpy(out->data[0],
409			&s->start_silence_hold[s->start_silence_offset],
410			(s->start_silence_end - s->start_silence_offset) * sizeof(double));
411			}
412
413			if (s->start_silence_offset > 0) {
414			memcpy(out->data[0] + (s->start_silence_end - s->start_silence_offset) * sizeof(double),
415			&s->start_silence_hold[0],
416			s->start_silence_offset * sizeof(double));
417			}
418			}
419
420		341	memcpy(out->data[0] + s->start_silence_end * sizeof(double),
421		341	&s->start_holdoff[s->start_holdoff_offset],
422			nbs * sizeof(double));
423
424		341	out->pts = s->next_pts;
425		341	s->next_pts += av_rescale_q(out->nb_samples,
426		341	(AVRational){1, outlink->sample_rate},
427			outlink->time_base);
428
429		341	s->start_holdoff_offset += nbs;
430
431		341	ret = ff_filter_frame(outlink, out);
432
433	✓✗	341	if (s->start_holdoff_offset == s->start_holdoff_end) {
434		341	s->start_holdoff_offset = 0;
435		341	s->start_holdoff_end = 0;
436		341	s->start_silence_offset = 0;
437		341	s->start_silence_end = 0;
438		341	s->mode = SILENCE_COPY;
439		341	goto silence_copy;
440			}
441			break;
442
443			case SILENCE_COPY:
444		342	silence_copy:
445		342	nbs = in->nb_samples - nb_samples_read / outlink->channels;
446	✓✓	342	if (!nbs)
447		1	break;
448
449		341	out = ff_get_audio_buffer(outlink, nbs);
450	✗✓	341	if (!out) {
451			av_frame_free(&in);
452			return AVERROR(ENOMEM);
453			}
454		341	obuf = (double *)out->data[0];
455
456	✓✗	341	if (s->stop_periods) {
457	✓✗	341	for (i = 0; i < nbs; i++) {
458	✓✗	341	if (s->stop_mode == T_ANY) {
459		341	threshold = 0;
460	✓✓	1023	for (j = 0; j < outlink->channels; j++) {
461		682	threshold \|= s->compute(s, ibuf[j]) > s->stop_threshold;
462			}
463			} else {
464			threshold = 1;
465			for (j = 0; j < outlink->channels; j++) {
466			threshold &= s->compute(s, ibuf[j]) > s->stop_threshold;
467			}
468			}
469
470	✗✓✗✗ ✗✗	341	if (threshold && s->stop_holdoff_end && !s->stop_silence) {
471			s->mode = SILENCE_COPY_FLUSH;
472			flush(s, out, outlink, &nb_samples_written, &ret, 0);
473			goto silence_copy_flush;
474	✗✓	341	} else if (threshold) {
475			for (j = 0; j < outlink->channels; j++) {
476			s->update(s, *ibuf);
477			obuf++ = ibuf++;
478			}
479			nb_samples_read += outlink->channels;
480			nb_samples_written += outlink->channels;
481	✓✗	341	} else if (!threshold) {
482	✓✓	1023	for (j = 0; j < outlink->channels; j++) {
483		682	s->update(s, *ibuf);
484	✗✓	682	if (s->stop_silence) {
485			s->stop_silence_hold[s->stop_silence_offset++] = *ibuf;
486			s->stop_silence_end = FFMIN(s->stop_silence_end + 1, outlink->channels * s->stop_silence);
487			if (s->stop_silence_offset >= outlink->channels * s->stop_silence) {
488			s->stop_silence_offset = 0;
489			}
490			}
491
492		682	s->stop_holdoff[s->stop_holdoff_end++] = *ibuf++;
493			}
494		341	nb_samples_read += outlink->channels;
495
496	✓✗	341	if (s->stop_holdoff_end >= s->stop_duration * outlink->channels) {
497	✓✗	341	if (++s->stop_found_periods >= s->stop_periods) {
498		341	s->stop_holdoff_offset = 0;
499		341	s->stop_holdoff_end = 0;
500
501	✗✓	341	if (!s->restart) {
502			s->mode = SILENCE_STOP;
503			flush(s, out, outlink, &nb_samples_written, &ret, 1);
504			goto silence_stop;
505			} else {
506		341	s->stop_found_periods = 0;
507		341	s->start_found_periods = 0;
508		341	s->start_holdoff_offset = 0;
509		341	s->start_holdoff_end = 0;
510		341	s->start_silence_offset = 0;
511		341	s->start_silence_end = 0;
512		341	clear_window(s);
513		341	s->mode = SILENCE_TRIM;
514		341	flush(s, out, outlink, &nb_samples_written, &ret, 1);
515		341	goto silence_trim;
516			}
517			}
518			s->mode = SILENCE_COPY_FLUSH;
519			flush(s, out, outlink, &nb_samples_written, &ret, 0);
520			goto silence_copy_flush;
521			}
522			}
523			}
524			flush(s, out, outlink, &nb_samples_written, &ret, 0);
525			} else {
526			memcpy(obuf, ibuf, sizeof(double) * nbs * outlink->channels);
527
528			out->pts = s->next_pts;
529			s->next_pts += av_rescale_q(out->nb_samples,
530			(AVRational){1, outlink->sample_rate},
531			outlink->time_base);
532
533			ret = ff_filter_frame(outlink, out);
534			}
535			break;
536
537			case SILENCE_COPY_FLUSH:
538			silence_copy_flush:
539			nbs = s->stop_holdoff_end - s->stop_holdoff_offset;
540			nbs -= nbs % outlink->channels;
541			if (!nbs)
542			break;
543
544			out = ff_get_audio_buffer(outlink, nbs / outlink->channels);
545			if (!out) {
546			av_frame_free(&in);
547			return AVERROR(ENOMEM);
548			}
549
550			memcpy(out->data[0], &s->stop_holdoff[s->stop_holdoff_offset],
551			nbs * sizeof(double));
552			s->stop_holdoff_offset += nbs;
553
554			out->pts = s->next_pts;
555			s->next_pts += av_rescale_q(out->nb_samples,
556			(AVRational){1, outlink->sample_rate},
557			outlink->time_base);
558
559			ret = ff_filter_frame(outlink, out);
560
561			if (s->stop_holdoff_offset == s->stop_holdoff_end) {
562			s->stop_holdoff_offset = 0;
563			s->stop_holdoff_end = 0;
564			s->stop_silence_offset = 0;
565			s->stop_silence_end = 0;
566			s->mode = SILENCE_COPY;
567			goto silence_copy;
568			}
569			break;
570			case SILENCE_STOP:
571			silence_stop:
572			break;
573			}
574
575		1	av_frame_free(&in);
576
577		1	return ret;
578			}
579
580		1	static int request_frame(AVFilterLink *outlink)
581			{
582		1	AVFilterContext *ctx = outlink->src;
583		1	SilenceRemoveContext *s = ctx->priv;
584			int ret;
585
586		1	ret = ff_request_frame(ctx->inputs[0]);
587	✓✗✓✗	1	if (ret == AVERROR_EOF && (s->mode == SILENCE_COPY_FLUSH \|\|
588	✓✗	1	s->mode == SILENCE_COPY)) {
589		1	int nbs = s->stop_holdoff_end - s->stop_holdoff_offset;
590	✗✓	1	if (nbs) {
591			AVFrame *frame;
592
593			frame = ff_get_audio_buffer(outlink, nbs / outlink->channels);
594			if (!frame)
595			return AVERROR(ENOMEM);
596
597			memcpy(frame->data[0], &s->stop_holdoff[s->stop_holdoff_offset],
598			nbs * sizeof(double));
599
600			frame->pts = s->next_pts;
601			s->next_pts += av_rescale_q(frame->nb_samples,
602			(AVRational){1, outlink->sample_rate},
603			outlink->time_base);
604
605			ret = ff_filter_frame(outlink, frame);
606			}
607		1	s->mode = SILENCE_STOP;
608			}
609		1	return ret;
610			}
611
612		1	static int query_formats(AVFilterContext *ctx)
613			{
614		1	AVFilterFormats *formats = NULL;
615		1	AVFilterChannelLayouts *layouts = NULL;
616			static const enum AVSampleFormat sample_fmts[] = {
617			AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_NONE
618			};
619			int ret;
620
621		1	layouts = ff_all_channel_counts();
622	✗✓	1	if (!layouts)
623			return AVERROR(ENOMEM);
624		1	ret = ff_set_common_channel_layouts(ctx, layouts);
625	✗✓	1	if (ret < 0)
626			return ret;
627
628		1	formats = ff_make_format_list(sample_fmts);
629	✗✓	1	if (!formats)
630			return AVERROR(ENOMEM);
631		1	ret = ff_set_common_formats(ctx, formats);
632	✗✓	1	if (ret < 0)
633			return ret;
634
635		1	formats = ff_all_samplerates();
636	✗✓	1	if (!formats)
637			return AVERROR(ENOMEM);
638		1	return ff_set_common_samplerates(ctx, formats);
639			}
640
641		1	static av_cold void uninit(AVFilterContext *ctx)
642			{
643		1	SilenceRemoveContext *s = ctx->priv;
644
645		1	av_freep(&s->start_holdoff);
646		1	av_freep(&s->start_silence_hold);
647		1	av_freep(&s->stop_holdoff);
648		1	av_freep(&s->stop_silence_hold);
649		1	av_freep(&s->window);
650		1	}
651
652			static const AVFilterPad silenceremove_inputs[] = {
653			{
654			.name = "default",
655			.type = AVMEDIA_TYPE_AUDIO,
656			.config_props = config_input,
657			.filter_frame = filter_frame,
658			},
659			{ NULL }
660			};
661
662			static const AVFilterPad silenceremove_outputs[] = {
663			{
664			.name = "default",
665			.type = AVMEDIA_TYPE_AUDIO,
666			.request_frame = request_frame,
667			},
668			{ NULL }
669			};
670
671			AVFilter ff_af_silenceremove = {
672			.name = "silenceremove",
673			.description = NULL_IF_CONFIG_SMALL("Remove silence."),
674			.priv_size = sizeof(SilenceRemoveContext),
675			.priv_class = &silenceremove_class,
676			.init = init,
677			.uninit = uninit,
678			.query_formats = query_formats,
679			.inputs = silenceremove_inputs,
680			.outputs = silenceremove_outputs,
681			};