mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-07 11:13:41 +02:00
101 lines
3.0 KiB
C
101 lines
3.0 KiB
C
/*
|
|
* Copyright (c) 2012 Stefano Sabatini
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file framestep filter, inspired on libmpcodecs/vf_framestep.c by
|
|
* Daniele Fornighieri <guru AT digitalfantasy it>.
|
|
*/
|
|
|
|
#include "libavutil/opt.h"
|
|
#include "avfilter.h"
|
|
#include "internal.h"
|
|
#include "video.h"
|
|
|
|
typedef struct {
|
|
const AVClass *class;
|
|
int frame_step;
|
|
} FrameStepContext;
|
|
|
|
#define OFFSET(x) offsetof(FrameStepContext, x)
|
|
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
|
|
|
|
static const AVOption framestep_options[] = {
|
|
{ "step", "set frame step", OFFSET(frame_step), AV_OPT_TYPE_INT, {.i64=1}, 1, INT_MAX, FLAGS},
|
|
{NULL},
|
|
};
|
|
|
|
AVFILTER_DEFINE_CLASS(framestep);
|
|
|
|
static int config_output_props(AVFilterLink *outlink)
|
|
{
|
|
AVFilterContext *ctx = outlink->src;
|
|
FrameStepContext *framestep = ctx->priv;
|
|
AVFilterLink *inlink = ctx->inputs[0];
|
|
|
|
outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
|
|
outlink->frame_rate =
|
|
av_div_q(inlink->frame_rate, (AVRational){framestep->frame_step, 1});
|
|
|
|
av_log(ctx, AV_LOG_VERBOSE, "step:%d frame_rate:%d/%d(%f) -> frame_rate:%d/%d(%f)\n",
|
|
framestep->frame_step,
|
|
inlink->frame_rate.num, inlink->frame_rate.den, av_q2d(inlink->frame_rate),
|
|
outlink->frame_rate.num, outlink->frame_rate.den, av_q2d(outlink->frame_rate));
|
|
return 0;
|
|
}
|
|
|
|
static int filter_frame(AVFilterLink *inlink, AVFrame *ref)
|
|
{
|
|
FrameStepContext *framestep = inlink->dst->priv;
|
|
|
|
if (!(inlink->frame_count % framestep->frame_step)) {
|
|
return ff_filter_frame(inlink->dst->outputs[0], ref);
|
|
} else {
|
|
av_frame_free(&ref);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static const AVFilterPad framestep_inputs[] = {
|
|
{
|
|
.name = "default",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.filter_frame = filter_frame,
|
|
},
|
|
{ NULL }
|
|
};
|
|
|
|
static const AVFilterPad framestep_outputs[] = {
|
|
{
|
|
.name = "default",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.config_props = config_output_props,
|
|
},
|
|
{ NULL }
|
|
};
|
|
|
|
AVFilter avfilter_vf_framestep = {
|
|
.name = "framestep",
|
|
.description = NULL_IF_CONFIG_SMALL("Select one frame every N frames."),
|
|
.priv_size = sizeof(FrameStepContext),
|
|
.priv_class = &framestep_class,
|
|
.inputs = framestep_inputs,
|
|
.outputs = framestep_outputs,
|
|
};
|