Files
FFmpeg/libavfilter/f_cue.c
T
Michael Niedermayer 58892c922e avfilter: declare the filters that carry no frame parameter state as handling changes
These filters never access pixel data based on the size or format of
their input link, so frames that change size or
format after the graph was configured pass through them unharmed.
Marking them keeps the common -reinit_filter 0 chains working.

Found during triage of the security report RqgTntCAW2qN.
2026-10-12 00:42:48 +00:00

127 lines
4.3 KiB
C

/*
* Copyright (c) 2018 Marton Balint
*
* 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 "config_components.h"
#include "libavutil/opt.h"
#include "libavutil/time.h"
#include "audio.h"
#include "avfilter.h"
#include "filters.h"
#include "video.h"
typedef struct CueContext {
const AVClass *class;
int64_t first_pts;
int64_t cue;
int64_t preroll;
int64_t buffer;
int status;
} CueContext;
static int activate(AVFilterContext *ctx)
{
AVFilterLink *inlink = ctx->inputs[0];
AVFilterLink *outlink = ctx->outputs[0];
CueContext *s = ctx->priv;
FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);
if (ff_inlink_queued_frames(inlink)) {
AVFrame *frame = ff_inlink_peek_frame(inlink, 0);
int64_t pts = av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q);
if (!s->status) {
s->first_pts = pts;
s->status++;
}
if (s->status == 1) {
if (pts - s->first_pts < s->preroll) {
int ret = ff_inlink_consume_frame(inlink, &frame);
if (ret < 0)
return ret;
return ff_filter_frame(outlink, frame);
}
s->first_pts = pts;
s->status++;
}
if (s->status == 2) {
frame = ff_inlink_peek_frame(inlink, ff_inlink_queued_frames(inlink) - 1);
pts = av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q);
if (!(pts - s->first_pts < s->buffer && (av_gettime() - s->cue) < 0))
s->status++;
}
if (s->status == 3) {
int64_t diff;
while ((diff = (av_gettime() - s->cue)) < 0)
av_usleep(av_clip(-diff / 2, 100, 1000000));
s->status++;
}
if (s->status == 4) {
int ret = ff_inlink_consume_frame(inlink, &frame);
if (ret < 0)
return ret;
return ff_filter_frame(outlink, frame);
}
}
FF_FILTER_FORWARD_STATUS(inlink, outlink);
FF_FILTER_FORWARD_WANTED(outlink, inlink);
return FFERROR_NOT_READY;
}
#define OFFSET(x) offsetof(CueContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
static const AVOption options[] = {
{ "cue", "cue unix timestamp in microseconds", OFFSET(cue), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT64_MAX, FLAGS },
{ "preroll", "preroll duration in seconds", OFFSET(preroll), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS },
{ "buffer", "buffer duration in seconds", OFFSET(buffer), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS_EXT(cue_acue, "(a)cue", options);
#if CONFIG_CUE_FILTER
const FFFilter ff_vf_cue = {
.p.name = "cue",
.p.description = NULL_IF_CONFIG_SMALL("Delay filtering to match a cue."),
.p.priv_class = &cue_acue_class,
.priv_size = sizeof(CueContext),
FILTER_INPUTS(ff_video_default_filterpad),
FILTER_OUTPUTS(ff_video_default_filterpad),
.activate = activate,
.flags_internal = FF_FILTER_FLAG_DYNAMIC_FRAME_PARAMS,
};
#endif /* CONFIG_CUE_FILTER */
#if CONFIG_ACUE_FILTER
const FFFilter ff_af_acue = {
.p.name = "acue",
.p.description = NULL_IF_CONFIG_SMALL("Delay filtering to match a cue."),
.p.priv_class = &cue_acue_class,
.p.flags = AVFILTER_FLAG_METADATA_ONLY,
.priv_size = sizeof(CueContext),
FILTER_INPUTS(ff_audio_default_filterpad),
FILTER_OUTPUTS(ff_audio_default_filterpad),
.activate = activate,
};
#endif /* CONFIG_ACUE_FILTER */