FFmpeg/libavfilter/setpts.c
Stefano Sabatini 018bdaed37 setpts: add FRAME_RATE constant
Useful for dealing with constant frame-rate video.

(cherry picked from ffmpeg commit 722762f7e1)

Signed-off-by: Anton Khirnov <anton@khirnov.net>
2015-11-09 08:09:41 +01:00

268 lines
7.7 KiB
C

/*
* Copyright (c) 2010 Stefano Sabatini
* Copyright (c) 2008 Victor Paesa
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* video presentation timestamp (PTS) modification filter
*/
#include <inttypes.h>
#include "libavutil/eval.h"
#include "libavutil/internal.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/time.h"
#include "audio.h"
#include "avfilter.h"
#include "internal.h"
#include "video.h"
#include "config.h"
static const char *const var_names[] = {
"E", ///< Euler number
"FRAME_RATE", ///< defined only for constant frame-rate video
"INTERLACED", ///< tell if the current frame is interlaced
"N", ///< frame / sample number (starting at zero)
"PHI", ///< golden ratio
"PI", ///< greek pi
"PREV_INPTS", ///< previous input PTS
"PREV_OUTPTS", ///< previous output PTS
"PTS", ///< original pts in the file of the frame
"STARTPTS", ///< PTS at start of movie
"TB", ///< timebase
"RTCTIME", ///< wallclock (RTC) time in micro seconds
"RTCSTART", ///< wallclock (RTC) time at the start of the movie in micro seconds
"S", // Number of samples in the current frame
"SR", // Audio sample rate
NULL
};
enum var_name {
VAR_E,
VAR_FRAME_RATE,
VAR_INTERLACED,
VAR_N,
VAR_PHI,
VAR_PI,
VAR_PREV_INPTS,
VAR_PREV_OUTPTS,
VAR_PTS,
VAR_STARTPTS,
VAR_TB,
VAR_RTCTIME,
VAR_RTCSTART,
VAR_S,
VAR_SR,
VAR_VARS_NB
};
typedef struct SetPTSContext {
const AVClass *class;
char *expr_str;
AVExpr *expr;
double var_values[VAR_VARS_NB];
} SetPTSContext;
static av_cold int init(AVFilterContext *ctx)
{
SetPTSContext *setpts = ctx->priv;
int ret;
if ((ret = av_expr_parse(&setpts->expr, setpts->expr_str,
var_names, NULL, NULL, NULL, NULL, 0, ctx)) < 0) {
av_log(ctx, AV_LOG_ERROR, "Error while parsing expression '%s'\n", setpts->expr_str);
return ret;
}
setpts->var_values[VAR_E] = M_E;
setpts->var_values[VAR_N] = 0.0;
setpts->var_values[VAR_S] = 0.0;
setpts->var_values[VAR_PHI] = M_PHI;
setpts->var_values[VAR_PI] = M_PI;
setpts->var_values[VAR_PREV_INPTS] = NAN;
setpts->var_values[VAR_PREV_OUTPTS] = NAN;
setpts->var_values[VAR_STARTPTS] = NAN;
return 0;
}
static int config_input(AVFilterLink *inlink)
{
SetPTSContext *setpts = inlink->dst->priv;
setpts->var_values[VAR_TB] = av_q2d(inlink->time_base);
setpts->var_values[VAR_RTCSTART] = av_gettime();
if (inlink->type == AVMEDIA_TYPE_AUDIO) {
setpts->var_values[VAR_SR] = inlink->sample_rate;
}
setpts->var_values[VAR_FRAME_RATE] = inlink->frame_rate.num &&
inlink->frame_rate.den ?
av_q2d(inlink->frame_rate) : NAN;
// Indicate the output can be variable framerate.
inlink->frame_rate = (AVRational){1, 0};
av_log(inlink->src, AV_LOG_VERBOSE, "TB:%f\n", setpts->var_values[VAR_TB]);
return 0;
}
#define D2TS(d) (isnan(d) ? AV_NOPTS_VALUE : (int64_t)(d))
#define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts))
static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
{
SetPTSContext *setpts = inlink->dst->priv;
int64_t in_pts = frame->pts;
double d;
if (isnan(setpts->var_values[VAR_STARTPTS]))
setpts->var_values[VAR_STARTPTS] = TS2D(frame->pts);
setpts->var_values[VAR_PTS ] = TS2D(frame->pts);
setpts->var_values[VAR_RTCTIME ] = av_gettime();
if (inlink->type == AVMEDIA_TYPE_VIDEO) {
setpts->var_values[VAR_INTERLACED] = frame->interlaced_frame;
} else {
setpts->var_values[VAR_S] = frame->nb_samples;
}
d = av_expr_eval(setpts->expr, setpts->var_values, NULL);
frame->pts = D2TS(d);
av_log(inlink->dst, AV_LOG_TRACE,
"n:%"PRId64" interlaced:%d pts:%"PRId64" t:%f -> pts:%"PRId64" t:%f\n",
(int64_t)setpts->var_values[VAR_N],
(int)setpts->var_values[VAR_INTERLACED],
in_pts, in_pts * av_q2d(inlink->time_base),
frame->pts, frame->pts * av_q2d(inlink->time_base));
if (inlink->type == AVMEDIA_TYPE_VIDEO) {
setpts->var_values[VAR_N] += 1.0;
} else {
setpts->var_values[VAR_N] += frame->nb_samples;
}
setpts->var_values[VAR_PREV_INPTS ] = TS2D(in_pts);
setpts->var_values[VAR_PREV_OUTPTS] = TS2D(frame->pts);
return ff_filter_frame(inlink->dst->outputs[0], frame);
}
static av_cold void uninit(AVFilterContext *ctx)
{
SetPTSContext *setpts = ctx->priv;
av_expr_free(setpts->expr);
setpts->expr = NULL;
}
#define OFFSET(x) offsetof(SetPTSContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM
static const AVOption options[] = {
{ "expr", "Expression determining the frame timestamp", OFFSET(expr_str), AV_OPT_TYPE_STRING, { .str = "PTS" }, .flags = FLAGS },
{ NULL },
};
#if CONFIG_SETPTS_FILTER
static const AVClass setpts_class = {
.class_name = "setpts",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
static const AVFilterPad avfilter_vf_setpts_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_video_buffer = ff_null_get_video_buffer,
.config_props = config_input,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad avfilter_vf_setpts_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter ff_vf_setpts = {
.name = "setpts",
.description = NULL_IF_CONFIG_SMALL("Set PTS for the output video frame."),
.init = init,
.uninit = uninit,
.priv_size = sizeof(SetPTSContext),
.priv_class = &setpts_class,
.inputs = avfilter_vf_setpts_inputs,
.outputs = avfilter_vf_setpts_outputs,
};
#endif
#if CONFIG_ASETPTS_FILTER
static const AVClass asetpts_class = {
.class_name = "asetpts",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
static const AVFilterPad asetpts_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.get_audio_buffer = ff_null_get_audio_buffer,
.config_props = config_input,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad asetpts_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
},
{ NULL }
};
AVFilter ff_af_asetpts = {
.name = "asetpts",
.description = NULL_IF_CONFIG_SMALL("Set PTS for the output audio frame."),
.init = init,
.uninit = uninit,
.priv_size = sizeof(SetPTSContext),
.priv_class = &asetpts_class,
.inputs = asetpts_inputs,
.outputs = asetpts_outputs,
};
#endif