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FFmpeg/libavfilter/trim.c
Anton Khirnov b9c928a486 avfilter: add AVFILTER_FLAG_METADATA_ONLY
This flag allows distinguishing between filters that actually modify the
data and those that only modify metadata or gather some stream
information.
2021-12-04 14:07:19 +01:00

371 lines
13 KiB
C

/*
* 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 <stdint.h>
#include "config.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/log.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/samplefmt.h"
#include "audio.h"
#include "avfilter.h"
#include "internal.h"
typedef struct TrimContext {
const AVClass *class;
/*
* AVOptions
*/
int64_t duration;
int64_t start_time, end_time;
int64_t start_frame, end_frame;
/*
* in the link timebase for video,
* in 1/samplerate for audio
*/
int64_t start_pts, end_pts;
int64_t start_sample, end_sample;
/*
* number of video frames that arrived on this filter so far
*/
int64_t nb_frames;
/*
* number of audio samples that arrived on this filter so far
*/
int64_t nb_samples;
/*
* timestamp of the first frame in the output, in the timebase units
*/
int64_t first_pts;
/*
* duration in the timebase units
*/
int64_t duration_tb;
int64_t next_pts;
int eof;
} TrimContext;
static av_cold int init(AVFilterContext *ctx)
{
TrimContext *s = ctx->priv;
s->first_pts = AV_NOPTS_VALUE;
return 0;
}
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
TrimContext *s = ctx->priv;
AVRational tb = (inlink->type == AVMEDIA_TYPE_VIDEO) ?
inlink->time_base : (AVRational){ 1, inlink->sample_rate };
if (s->start_time != INT64_MAX) {
int64_t start_pts = av_rescale_q(s->start_time, AV_TIME_BASE_Q, tb);
if (s->start_pts == AV_NOPTS_VALUE || start_pts < s->start_pts)
s->start_pts = start_pts;
}
if (s->end_time != INT64_MAX) {
int64_t end_pts = av_rescale_q(s->end_time, AV_TIME_BASE_Q, tb);
if (s->end_pts == AV_NOPTS_VALUE || end_pts > s->end_pts)
s->end_pts = end_pts;
}
if (s->duration)
s->duration_tb = av_rescale_q(s->duration, AV_TIME_BASE_Q, tb);
return 0;
}
#define OFFSET(x) offsetof(TrimContext, x)
#define COMMON_OPTS \
{ "start", "Timestamp of the first frame that " \
"should be passed", OFFSET(start_time), AV_OPT_TYPE_DURATION, { .i64 = INT64_MAX }, INT64_MIN, INT64_MAX, FLAGS }, \
{ "starti", "Timestamp of the first frame that " \
"should be passed", OFFSET(start_time), AV_OPT_TYPE_DURATION, { .i64 = INT64_MAX }, INT64_MIN, INT64_MAX, FLAGS }, \
{ "end", "Timestamp of the first frame that " \
"should be dropped again", OFFSET(end_time), AV_OPT_TYPE_DURATION, { .i64 = INT64_MAX }, INT64_MIN, INT64_MAX, FLAGS }, \
{ "endi", "Timestamp of the first frame that " \
"should be dropped again", OFFSET(end_time), AV_OPT_TYPE_DURATION, { .i64 = INT64_MAX }, INT64_MIN, INT64_MAX, FLAGS }, \
{ "start_pts", "Timestamp of the first frame that should be " \
" passed", OFFSET(start_pts), AV_OPT_TYPE_INT64, { .i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, FLAGS }, \
{ "end_pts", "Timestamp of the first frame that should be " \
"dropped again", OFFSET(end_pts), AV_OPT_TYPE_INT64, { .i64 = AV_NOPTS_VALUE }, INT64_MIN, INT64_MAX, FLAGS }, \
{ "duration", "Maximum duration of the output", OFFSET(duration), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS }, \
{ "durationi", "Maximum duration of the output", OFFSET(duration), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS },
#if CONFIG_TRIM_FILTER
static int trim_filter_frame(AVFilterLink *inlink, AVFrame *frame)
{
AVFilterContext *ctx = inlink->dst;
TrimContext *s = ctx->priv;
int drop;
/* drop everything if EOF has already been returned */
if (s->eof) {
av_frame_free(&frame);
return 0;
}
if (s->start_frame >= 0 || s->start_pts != AV_NOPTS_VALUE) {
drop = 1;
if (s->start_frame >= 0 && s->nb_frames >= s->start_frame)
drop = 0;
if (s->start_pts != AV_NOPTS_VALUE && frame->pts != AV_NOPTS_VALUE &&
frame->pts >= s->start_pts)
drop = 0;
if (drop)
goto drop;
}
if (s->first_pts == AV_NOPTS_VALUE && frame->pts != AV_NOPTS_VALUE)
s->first_pts = frame->pts;
if (s->end_frame != INT64_MAX || s->end_pts != AV_NOPTS_VALUE || s->duration_tb) {
drop = 1;
if (s->end_frame != INT64_MAX && s->nb_frames < s->end_frame)
drop = 0;
if (s->end_pts != AV_NOPTS_VALUE && frame->pts != AV_NOPTS_VALUE &&
frame->pts < s->end_pts)
drop = 0;
if (s->duration_tb && frame->pts != AV_NOPTS_VALUE &&
frame->pts - s->first_pts < s->duration_tb)
drop = 0;
if (drop) {
s->eof = 1;
ff_avfilter_link_set_out_status(inlink, AVERROR_EOF, AV_NOPTS_VALUE);
goto drop;
}
}
s->nb_frames++;
return ff_filter_frame(ctx->outputs[0], frame);
drop:
s->nb_frames++;
av_frame_free(&frame);
return 0;
}
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
static const AVOption trim_options[] = {
COMMON_OPTS
{ "start_frame", "Number of the first frame that should be passed "
"to the output", OFFSET(start_frame), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, FLAGS },
{ "end_frame", "Number of the first frame that should be dropped "
"again", OFFSET(end_frame), AV_OPT_TYPE_INT64, { .i64 = INT64_MAX }, 0, INT64_MAX, FLAGS },
{ NULL }
};
#undef FLAGS
AVFILTER_DEFINE_CLASS(trim);
static const AVFilterPad trim_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = trim_filter_frame,
.config_props = config_input,
},
};
static const AVFilterPad trim_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
};
const AVFilter ff_vf_trim = {
.name = "trim",
.description = NULL_IF_CONFIG_SMALL("Pick one continuous section from the input, drop the rest."),
.init = init,
.priv_size = sizeof(TrimContext),
.priv_class = &trim_class,
FILTER_INPUTS(trim_inputs),
FILTER_OUTPUTS(trim_outputs),
};
#endif // CONFIG_TRIM_FILTER
#if CONFIG_ATRIM_FILTER
static int atrim_filter_frame(AVFilterLink *inlink, AVFrame *frame)
{
AVFilterContext *ctx = inlink->dst;
TrimContext *s = ctx->priv;
int64_t start_sample, end_sample;
int64_t pts;
int drop;
/* drop everything if EOF has already been returned */
if (s->eof) {
av_frame_free(&frame);
return 0;
}
if (frame->pts != AV_NOPTS_VALUE)
pts = av_rescale_q(frame->pts, inlink->time_base,
(AVRational){ 1, inlink->sample_rate });
else
pts = s->next_pts;
s->next_pts = pts + frame->nb_samples;
/* check if at least a part of the frame is after the start time */
if (s->start_sample < 0 && s->start_pts == AV_NOPTS_VALUE) {
start_sample = 0;
} else {
drop = 1;
start_sample = frame->nb_samples;
if (s->start_sample >= 0 &&
s->nb_samples + frame->nb_samples > s->start_sample) {
drop = 0;
start_sample = FFMIN(start_sample, s->start_sample - s->nb_samples);
}
if (s->start_pts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE &&
pts + frame->nb_samples > s->start_pts) {
drop = 0;
start_sample = FFMIN(start_sample, s->start_pts - pts);
}
if (drop)
goto drop;
}
if (s->first_pts == AV_NOPTS_VALUE)
s->first_pts = pts + start_sample;
/* check if at least a part of the frame is before the end time */
if (s->end_sample == INT64_MAX && s->end_pts == AV_NOPTS_VALUE && !s->duration_tb) {
end_sample = frame->nb_samples;
} else {
drop = 1;
end_sample = 0;
if (s->end_sample != INT64_MAX &&
s->nb_samples < s->end_sample) {
drop = 0;
end_sample = FFMAX(end_sample, s->end_sample - s->nb_samples);
}
if (s->end_pts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE &&
pts < s->end_pts) {
drop = 0;
end_sample = FFMAX(end_sample, s->end_pts - pts);
}
if (s->duration_tb && pts - s->first_pts < s->duration_tb) {
drop = 0;
end_sample = FFMAX(end_sample, s->first_pts + s->duration_tb - pts);
}
if (drop) {
s->eof = 1;
ff_avfilter_link_set_out_status(inlink, AVERROR_EOF, AV_NOPTS_VALUE);
goto drop;
}
}
s->nb_samples += frame->nb_samples;
start_sample = FFMAX(0, start_sample);
end_sample = FFMIN(frame->nb_samples, end_sample);
if (start_sample >= end_sample || !frame->nb_samples)
goto drop;
if (start_sample) {
AVFrame *out = ff_get_audio_buffer(ctx->outputs[0], end_sample - start_sample);
if (!out) {
av_frame_free(&frame);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, frame);
av_samples_copy(out->extended_data, frame->extended_data, 0, start_sample,
out->nb_samples, inlink->channels,
frame->format);
if (out->pts != AV_NOPTS_VALUE)
out->pts += av_rescale_q(start_sample, (AVRational){ 1, out->sample_rate },
inlink->time_base);
av_frame_free(&frame);
frame = out;
} else
frame->nb_samples = end_sample;
return ff_filter_frame(ctx->outputs[0], frame);
drop:
s->nb_samples += frame->nb_samples;
av_frame_free(&frame);
return 0;
}
#define FLAGS AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
static const AVOption atrim_options[] = {
COMMON_OPTS
{ "start_sample", "Number of the first audio sample that should be "
"passed to the output", OFFSET(start_sample), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, FLAGS },
{ "end_sample", "Number of the first audio sample that should be "
"dropped again", OFFSET(end_sample), AV_OPT_TYPE_INT64, { .i64 = INT64_MAX }, 0, INT64_MAX, FLAGS },
{ NULL }
};
#undef FLAGS
AVFILTER_DEFINE_CLASS(atrim);
static const AVFilterPad atrim_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.filter_frame = atrim_filter_frame,
.config_props = config_input,
},
};
static const AVFilterPad atrim_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
},
};
const AVFilter ff_af_atrim = {
.name = "atrim",
.description = NULL_IF_CONFIG_SMALL("Pick one continuous section from the input, drop the rest."),
.init = init,
.priv_size = sizeof(TrimContext),
.priv_class = &atrim_class,
.flags = AVFILTER_FLAG_METADATA_ONLY,
FILTER_INPUTS(atrim_inputs),
FILTER_OUTPUTS(atrim_outputs),
};
#endif // CONFIG_ATRIM_FILTER