libavfilter/vf_fps.c - nest-android-app/ffmpeg - Git at Google

 /*
  * Copyright 2007 Bobby Bingham
  * Copyright 2012 Robert Nagy <ronag89 gmail com>
  * Copyright 2012 Anton Khirnov <anton khirnov net>
  *
  * 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
  * a filter enforcing given constant framerate
  */

 #include <float.h>
 #include <stdint.h>

 #include "libavutil/common.h"
 #include "libavutil/fifo.h"
 #include "libavutil/mathematics.h"
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"

 #include "avfilter.h"
 #include "internal.h"
 #include "video.h"

 typedef struct FPSContext {
     const AVClass *class;

     AVFifoBuffer *fifo;     ///< store frames until we get two successive timestamps

     /* timestamps in input timebase */
     int64_t first_pts;      ///< pts of the first frame that arrived on this filter

     double start_time;      ///< pts, in seconds, of the expected first frame

     AVRational framerate;   ///< target framerate
     int rounding;           ///< AVRounding method for timestamps

     /* statistics */
     int frames_in;             ///< number of frames on input
     int frames_out;            ///< number of frames on output
     int dup;                   ///< number of frames duplicated
     int drop;                  ///< number of framed dropped
 } FPSContext;

 #define OFFSET(x) offsetof(FPSContext, x)
 #define V AV_OPT_FLAG_VIDEO_PARAM
 #define F AV_OPT_FLAG_FILTERING_PARAM
 static const AVOption fps_options[] = {
     { "fps", "A string describing desired output framerate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, { .str = "25" }, .flags = V|F },
     { "start_time", "Assume the first PTS should be this value.", OFFSET(start_time), AV_OPT_TYPE_DOUBLE, { .dbl = DBL_MAX}, -DBL_MAX, DBL_MAX, V },
     { "round", "set rounding method for timestamps", OFFSET(rounding), AV_OPT_TYPE_INT, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V|F, "round" },
     { "zero", "round towards 0",      OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_ZERO     }, 0, 5, V|F, "round" },
     { "inf",  "round away from 0",    OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_INF      }, 0, 5, V|F, "round" },
     { "down", "round towards -infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_DOWN     }, 0, 5, V|F, "round" },
     { "up",   "round towards +infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_UP       }, 0, 5, V|F, "round" },
     { "near", "round to nearest",     OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V|F, "round" },
     { NULL }
 };

 AVFILTER_DEFINE_CLASS(fps);

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

     if (!(s->fifo = av_fifo_alloc_array(2, sizeof(AVFrame*))))
         return AVERROR(ENOMEM);

     s->first_pts    = AV_NOPTS_VALUE;

     av_log(ctx, AV_LOG_VERBOSE, "fps=%d/%d\n", s->framerate.num, s->framerate.den);
     return 0;
 }

 static void flush_fifo(AVFifoBuffer *fifo)
 {
     while (av_fifo_size(fifo)) {
         AVFrame *tmp;
         av_fifo_generic_read(fifo, &tmp, sizeof(tmp), NULL);
         av_frame_free(&tmp);
     }
 }

 static av_cold void uninit(AVFilterContext *ctx)
 {
     FPSContext *s = ctx->priv;
     if (s->fifo) {
         s->drop += av_fifo_size(s->fifo) / sizeof(AVFrame*);
         flush_fifo(s->fifo);
         av_fifo_freep(&s->fifo);
     }

     av_log(ctx, AV_LOG_VERBOSE, "%d frames in, %d frames out; %d frames dropped, "
            "%d frames duplicated.\n", s->frames_in, s->frames_out, s->drop, s->dup);
 }

 static int config_props(AVFilterLink* link)
 {
     FPSContext   *s = link->src->priv;

     link->time_base = av_inv_q(s->framerate);
     link->frame_rate= s->framerate;
     link->w         = link->src->inputs[0]->w;
     link->h         = link->src->inputs[0]->h;

     return 0;
 }

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

     ret = ff_request_frame(ctx->inputs[0]);

     /* flush the fifo */
     if (ret == AVERROR_EOF && av_fifo_size(s->fifo)) {
         int i;
         for (i = 0; av_fifo_size(s->fifo); i++) {
             AVFrame *buf;

             av_fifo_generic_read(s->fifo, &buf, sizeof(buf), NULL);
             buf->pts = av_rescale_q(s->first_pts, ctx->inputs[0]->time_base,
                                     outlink->time_base) + s->frames_out;

             if ((ret = ff_filter_frame(outlink, buf)) < 0)
                 return ret;

             s->frames_out++;
         }
         return 0;
     }

     return ret;
 }

 static int write_to_fifo(AVFifoBuffer *fifo, AVFrame *buf)
 {
     int ret;

     if (!av_fifo_space(fifo) &&
         (ret = av_fifo_realloc2(fifo, 2*av_fifo_size(fifo)))) {
         av_frame_free(&buf);
         return ret;
     }

     av_fifo_generic_write(fifo, &buf, sizeof(buf), NULL);
     return 0;
 }

 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
 {
     AVFilterContext    *ctx = inlink->dst;
     FPSContext           *s = ctx->priv;
     AVFilterLink   *outlink = ctx->outputs[0];
     int64_t delta;
     int i, ret;

     s->frames_in++;
     /* discard frames until we get the first timestamp */
     if (s->first_pts == AV_NOPTS_VALUE) {
         if (buf->pts != AV_NOPTS_VALUE) {
             ret = write_to_fifo(s->fifo, buf);
             if (ret < 0)
                 return ret;

             if (s->start_time != DBL_MAX && s->start_time != AV_NOPTS_VALUE) {
                 double first_pts = s->start_time * AV_TIME_BASE;
                 first_pts = FFMIN(FFMAX(first_pts, INT64_MIN), INT64_MAX);
                 s->first_pts = av_rescale_q(first_pts, AV_TIME_BASE_Q,
                                                      inlink->time_base);
                 av_log(ctx, AV_LOG_VERBOSE, "Set first pts to (in:%"PRId64" out:%"PRId64")\n",
                        s->first_pts, av_rescale_q(first_pts, AV_TIME_BASE_Q,
                                                   outlink->time_base));
             } else {
                 s->first_pts = buf->pts;
             }
         } else {
             av_log(ctx, AV_LOG_WARNING, "Discarding initial frame(s) with no "
                    "timestamp.\n");
             av_frame_free(&buf);
             s->drop++;
         }
         return 0;
     }

     /* now wait for the next timestamp */
     if (buf->pts == AV_NOPTS_VALUE || av_fifo_size(s->fifo) <= 0) {
         return write_to_fifo(s->fifo, buf);
     }

     /* number of output frames */
     delta = av_rescale_q_rnd(buf->pts - s->first_pts, inlink->time_base,
                              outlink->time_base, s->rounding) - s->frames_out ;

     if (delta < 1) {
         /* drop everything buffered except the last */
         int drop = av_fifo_size(s->fifo)/sizeof(AVFrame*);

         av_log(ctx, AV_LOG_DEBUG, "Dropping %d frame(s).\n", drop);
         s->drop += drop;

         flush_fifo(s->fifo);
         ret = write_to_fifo(s->fifo, buf);

         return ret;
     }

     /* can output >= 1 frames */
     for (i = 0; i < delta; i++) {
         AVFrame *buf_out;
         av_fifo_generic_read(s->fifo, &buf_out, sizeof(buf_out), NULL);

         /* duplicate the frame if needed */
         if (!av_fifo_size(s->fifo) && i < delta - 1) {
             AVFrame *dup = av_frame_clone(buf_out);

             av_log(ctx, AV_LOG_DEBUG, "Duplicating frame.\n");
             if (dup)
                 ret = write_to_fifo(s->fifo, dup);
             else
                 ret = AVERROR(ENOMEM);

             if (ret < 0) {
                 av_frame_free(&buf_out);
                 av_frame_free(&buf);
                 return ret;
             }

             s->dup++;
         }

         buf_out->pts = av_rescale_q(s->first_pts, inlink->time_base,
                                     outlink->time_base) + s->frames_out;

         if ((ret = ff_filter_frame(outlink, buf_out)) < 0) {
             av_frame_free(&buf);
             return ret;
         }

         s->frames_out++;
     }
     flush_fifo(s->fifo);

     ret = write_to_fifo(s->fifo, buf);

     return ret;
 }

 static const AVFilterPad avfilter_vf_fps_inputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,
     },
     { NULL }
 };

 static const AVFilterPad avfilter_vf_fps_outputs[] = {
     {
         .name          = "default",
         .type          = AVMEDIA_TYPE_VIDEO,
         .request_frame = request_frame,
         .config_props  = config_props
     },
     { NULL }
 };

 AVFilter ff_vf_fps = {
     .name        = "fps",
     .description = NULL_IF_CONFIG_SMALL("Force constant framerate."),
     .init        = init,
     .uninit      = uninit,
     .priv_size   = sizeof(FPSContext),
     .priv_class  = &fps_class,
     .inputs      = avfilter_vf_fps_inputs,
     .outputs     = avfilter_vf_fps_outputs,
 };
	/*
	* Copyright 2007 Bobby Bingham
	* Copyright 2012 Robert Nagy <ronag89 gmail com>
	* Copyright 2012 Anton Khirnov <anton khirnov net>
	*
	* 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
	* a filter enforcing given constant framerate
	*/

	#include <float.h>
	#include <stdint.h>

	#include "libavutil/common.h"
	#include "libavutil/fifo.h"
	#include "libavutil/mathematics.h"
	#include "libavutil/opt.h"
	#include "libavutil/parseutils.h"

	#include "avfilter.h"
	#include "internal.h"
	#include "video.h"

	typedef struct FPSContext {
	const AVClass *class;

	AVFifoBuffer *fifo; ///< store frames until we get two successive timestamps

	/* timestamps in input timebase */
	int64_t first_pts; ///< pts of the first frame that arrived on this filter

	double start_time; ///< pts, in seconds, of the expected first frame

	AVRational framerate; ///< target framerate
	int rounding; ///< AVRounding method for timestamps

	/* statistics */
	int frames_in; ///< number of frames on input
	int frames_out; ///< number of frames on output
	int dup; ///< number of frames duplicated
	int drop; ///< number of framed dropped
	} FPSContext;

	#define OFFSET(x) offsetof(FPSContext, x)
	#define V AV_OPT_FLAG_VIDEO_PARAM
	#define F AV_OPT_FLAG_FILTERING_PARAM
	static const AVOption fps_options[] = {
	{ "fps", "A string describing desired output framerate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, { .str = "25" }, .flags = V\|F },
	{ "start_time", "Assume the first PTS should be this value.", OFFSET(start_time), AV_OPT_TYPE_DOUBLE, { .dbl = DBL_MAX}, -DBL_MAX, DBL_MAX, V },
	{ "round", "set rounding method for timestamps", OFFSET(rounding), AV_OPT_TYPE_INT, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V\|F, "round" },
	{ "zero", "round towards 0", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_ZERO }, 0, 5, V\|F, "round" },
	{ "inf", "round away from 0", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_INF }, 0, 5, V\|F, "round" },
	{ "down", "round towards -infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_DOWN }, 0, 5, V\|F, "round" },
	{ "up", "round towards +infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_UP }, 0, 5, V\|F, "round" },
	{ "near", "round to nearest", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V\|F, "round" },
	{ NULL }
	};

	AVFILTER_DEFINE_CLASS(fps);

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

	if (!(s->fifo = av_fifo_alloc_array(2, sizeof(AVFrame*))))
	return AVERROR(ENOMEM);

	s->first_pts = AV_NOPTS_VALUE;

	av_log(ctx, AV_LOG_VERBOSE, "fps=%d/%d\n", s->framerate.num, s->framerate.den);
	return 0;
	}

	static void flush_fifo(AVFifoBuffer *fifo)
	{
	while (av_fifo_size(fifo)) {
	AVFrame *tmp;
	av_fifo_generic_read(fifo, &tmp, sizeof(tmp), NULL);
	av_frame_free(&tmp);
	}
	}

	static av_cold void uninit(AVFilterContext *ctx)
	{
	FPSContext *s = ctx->priv;
	if (s->fifo) {
	s->drop += av_fifo_size(s->fifo) / sizeof(AVFrame*);
	flush_fifo(s->fifo);
	av_fifo_freep(&s->fifo);
	}

	av_log(ctx, AV_LOG_VERBOSE, "%d frames in, %d frames out; %d frames dropped, "
	"%d frames duplicated.\n", s->frames_in, s->frames_out, s->drop, s->dup);
	}

	static int config_props(AVFilterLink* link)
	{
	FPSContext *s = link->src->priv;

	link->time_base = av_inv_q(s->framerate);
	link->frame_rate= s->framerate;
	link->w = link->src->inputs[0]->w;
	link->h = link->src->inputs[0]->h;

	return 0;
	}

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

	ret = ff_request_frame(ctx->inputs[0]);

	/* flush the fifo */
	if (ret == AVERROR_EOF && av_fifo_size(s->fifo)) {
	int i;
	for (i = 0; av_fifo_size(s->fifo); i++) {
	AVFrame *buf;

	av_fifo_generic_read(s->fifo, &buf, sizeof(buf), NULL);
	buf->pts = av_rescale_q(s->first_pts, ctx->inputs[0]->time_base,
	outlink->time_base) + s->frames_out;

	if ((ret = ff_filter_frame(outlink, buf)) < 0)
	return ret;

	s->frames_out++;
	}
	return 0;
	}

	return ret;
	}

	static int write_to_fifo(AVFifoBuffer fifo, AVFrame buf)
	{
	int ret;

	if (!av_fifo_space(fifo) &&
	(ret = av_fifo_realloc2(fifo, 2*av_fifo_size(fifo)))) {
	av_frame_free(&buf);
	return ret;
	}

	av_fifo_generic_write(fifo, &buf, sizeof(buf), NULL);
	return 0;
	}

	static int filter_frame(AVFilterLink inlink, AVFrame buf)
	{
	AVFilterContext *ctx = inlink->dst;
	FPSContext *s = ctx->priv;
	AVFilterLink *outlink = ctx->outputs[0];
	int64_t delta;
	int i, ret;

	s->frames_in++;
	/* discard frames until we get the first timestamp */
	if (s->first_pts == AV_NOPTS_VALUE) {
	if (buf->pts != AV_NOPTS_VALUE) {
	ret = write_to_fifo(s->fifo, buf);
	if (ret < 0)
	return ret;

	if (s->start_time != DBL_MAX && s->start_time != AV_NOPTS_VALUE) {
	double first_pts = s->start_time * AV_TIME_BASE;
	first_pts = FFMIN(FFMAX(first_pts, INT64_MIN), INT64_MAX);
	s->first_pts = av_rescale_q(first_pts, AV_TIME_BASE_Q,
	inlink->time_base);
	av_log(ctx, AV_LOG_VERBOSE, "Set first pts to (in:%"PRId64" out:%"PRId64")\n",
	s->first_pts, av_rescale_q(first_pts, AV_TIME_BASE_Q,
	outlink->time_base));
	} else {
	s->first_pts = buf->pts;
	}
	} else {
	av_log(ctx, AV_LOG_WARNING, "Discarding initial frame(s) with no "
	"timestamp.\n");
	av_frame_free(&buf);
	s->drop++;
	}
	return 0;
	}

	/* now wait for the next timestamp */
	if (buf->pts == AV_NOPTS_VALUE \|\| av_fifo_size(s->fifo) <= 0) {
	return write_to_fifo(s->fifo, buf);
	}

	/* number of output frames */
	delta = av_rescale_q_rnd(buf->pts - s->first_pts, inlink->time_base,
	outlink->time_base, s->rounding) - s->frames_out ;

	if (delta < 1) {
	/* drop everything buffered except the last */
	int drop = av_fifo_size(s->fifo)/sizeof(AVFrame*);

	av_log(ctx, AV_LOG_DEBUG, "Dropping %d frame(s).\n", drop);
	s->drop += drop;

	flush_fifo(s->fifo);
	ret = write_to_fifo(s->fifo, buf);

	return ret;
	}

	/* can output >= 1 frames */
	for (i = 0; i < delta; i++) {
	AVFrame *buf_out;
	av_fifo_generic_read(s->fifo, &buf_out, sizeof(buf_out), NULL);

	/* duplicate the frame if needed */
	if (!av_fifo_size(s->fifo) && i < delta - 1) {
	AVFrame *dup = av_frame_clone(buf_out);

	av_log(ctx, AV_LOG_DEBUG, "Duplicating frame.\n");
	if (dup)
	ret = write_to_fifo(s->fifo, dup);
	else
	ret = AVERROR(ENOMEM);

	if (ret < 0) {
	av_frame_free(&buf_out);
	av_frame_free(&buf);
	return ret;
	}

	s->dup++;
	}

	buf_out->pts = av_rescale_q(s->first_pts, inlink->time_base,
	outlink->time_base) + s->frames_out;

	if ((ret = ff_filter_frame(outlink, buf_out)) < 0) {
	av_frame_free(&buf);
	return ret;
	}

	s->frames_out++;
	}
	flush_fifo(s->fifo);

	ret = write_to_fifo(s->fifo, buf);

	return ret;
	}

	static const AVFilterPad avfilter_vf_fps_inputs[] = {
	{
	.name = "default",
	.type = AVMEDIA_TYPE_VIDEO,
	.filter_frame = filter_frame,
	},
	{ NULL }
	};

	static const AVFilterPad avfilter_vf_fps_outputs[] = {
	{
	.name = "default",
	.type = AVMEDIA_TYPE_VIDEO,
	.request_frame = request_frame,
	.config_props = config_props
	},
	{ NULL }
	};

	AVFilter ff_vf_fps = {
	.name = "fps",
	.description = NULL_IF_CONFIG_SMALL("Force constant framerate."),
	.init = init,
	.uninit = uninit,
	.priv_size = sizeof(FPSContext),
	.priv_class = &fps_class,
	.inputs = avfilter_vf_fps_inputs,
	.outputs = avfilter_vf_fps_outputs,
	};