libavdevice/lavfi.c - third_party/ffmpeg - Git at Google

 /*
  * Copyright (c) 2011 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
  * libavfilter virtual input device
  */

 /* #define DEBUG */

 #include "float.h"              /* DBL_MIN, DBL_MAX */

 #include "libavutil/log.h"
 #include "libavutil/mem.h"
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 #include "libavutil/pixdesc.h"
 #include "libavfilter/avfilter.h"
 #include "libavfilter/avfiltergraph.h"
 #include "libavfilter/buffersink.h"
 #include "libavformat/internal.h"
 #include "avdevice.h"

 typedef struct {
     AVClass *class;          ///< class for private options
     char          *graph_str;
     char          *dump_graph;
     AVFilterGraph *graph;
     AVFilterContext **sinks;
     int *sink_stream_map;
     int *stream_sink_map;
 } LavfiContext;

 static int *create_all_formats(int n)
 {
     int i, j, *fmts, count = 0;

     for (i = 0; i < n; i++)
         if (!(av_pix_fmt_descriptors[i].flags & PIX_FMT_HWACCEL))
             count++;

     if (!(fmts = av_malloc((count+1) * sizeof(int))))
         return NULL;
     for (j = 0, i = 0; i < n; i++) {
         if (!(av_pix_fmt_descriptors[i].flags & PIX_FMT_HWACCEL))
             fmts[j++] = i;
     }
     fmts[j] = -1;
     return fmts;
 }

 av_cold static int lavfi_read_close(AVFormatContext *avctx)
 {
     LavfiContext *lavfi = avctx->priv_data;

     av_freep(&lavfi->sink_stream_map);
     av_freep(&lavfi->stream_sink_map);
     av_freep(&lavfi->sinks);
     avfilter_graph_free(&lavfi->graph);

     return 0;
 }

 av_cold static int lavfi_read_header(AVFormatContext *avctx,
                                      AVFormatParameters *ap)
 {
     LavfiContext *lavfi = avctx->priv_data;
     AVFilterInOut *input_links = NULL, *output_links = NULL, *inout;
     AVFilter *buffersink, *abuffersink;
     int *pix_fmts = create_all_formats(PIX_FMT_NB);
     enum AVMediaType type;
     int ret = 0, i, n;

 #define FAIL(ERR) { ret = ERR; goto end; }

     if (!pix_fmts)
         FAIL(AVERROR(ENOMEM));

     avfilter_register_all();

     buffersink = avfilter_get_by_name("buffersink");
     abuffersink = avfilter_get_by_name("abuffersink");

     if (!lavfi->graph_str)
         lavfi->graph_str = av_strdup(avctx->filename);

     /* parse the graph, create a stream for each open output */
     if (!(lavfi->graph = avfilter_graph_alloc()))
         FAIL(AVERROR(ENOMEM));

     if ((ret = avfilter_graph_parse(lavfi->graph, lavfi->graph_str,
                                     &input_links, &output_links, avctx)) < 0)
         FAIL(ret);

     if (input_links) {
         av_log(avctx, AV_LOG_ERROR,
                "Open inputs in the filtergraph are not acceptable\n");
         FAIL(AVERROR(EINVAL));
     }

     /* count the outputs */
     for (n = 0, inout = output_links; inout; n++, inout = inout->next);

     if (!(lavfi->sink_stream_map = av_malloc(sizeof(int) * n)))
         FAIL(AVERROR(ENOMEM));
     if (!(lavfi->stream_sink_map = av_malloc(sizeof(int) * n)))
         FAIL(AVERROR(ENOMEM));

     for (i = 0; i < n; i++)
         lavfi->stream_sink_map[i] = -1;

     /* parse the output link names - they need to be of the form out0, out1, ...
      * create a mapping between them and the streams */
     for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
         int stream_idx;
         if (!strcmp(inout->name, "out"))
             stream_idx = 0;
         else if (sscanf(inout->name, "out%d\n", &stream_idx) != 1) {
             av_log(avctx,  AV_LOG_ERROR,
                    "Invalid outpad name '%s'\n", inout->name);
             FAIL(AVERROR(EINVAL));
         }

         if ((unsigned)stream_idx >= n) {
             av_log(avctx, AV_LOG_ERROR,
                    "Invalid index was specified in output '%s', "
                    "must be a non-negative value < %d\n",
                    inout->name, n);
             FAIL(AVERROR(EINVAL));
         }

         /* is an audio or video output? */
         type = inout->filter_ctx->output_pads[inout->pad_idx].type;
         if (type != AVMEDIA_TYPE_VIDEO && type != AVMEDIA_TYPE_AUDIO) {
             av_log(avctx,  AV_LOG_ERROR,
                    "Output '%s' is not a video or audio output, not yet supported\n", inout->name);
             FAIL(AVERROR(EINVAL));
         }

         if (lavfi->stream_sink_map[stream_idx] != -1) {
             av_log(avctx,  AV_LOG_ERROR,
                    "An output with stream index %d was already specified\n",
                    stream_idx);
             FAIL(AVERROR(EINVAL));
         }
         lavfi->sink_stream_map[i] = stream_idx;
         lavfi->stream_sink_map[stream_idx] = i;
     }

     /* for each open output create a corresponding stream */
     for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
         AVStream *st;
         if (!(st = avformat_new_stream(avctx, NULL)))
             FAIL(AVERROR(ENOMEM));
         st->id = i;
     }

     /* create a sink for each output and connect them to the graph */
     lavfi->sinks = av_malloc(sizeof(AVFilterContext *) * avctx->nb_streams);
     if (!lavfi->sinks)
         FAIL(AVERROR(ENOMEM));

     for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
         AVFilterContext *sink;

         type = inout->filter_ctx->output_pads[inout->pad_idx].type;

         if (type == AVMEDIA_TYPE_VIDEO && ! buffersink ||
             type == AVMEDIA_TYPE_AUDIO && ! abuffersink) {
                 av_log(avctx, AV_LOG_ERROR, "Missing required buffersink filter, aborting.\n");
                 FAIL(AVERROR_FILTER_NOT_FOUND);
         }

         if (type == AVMEDIA_TYPE_VIDEO) {
             AVBufferSinkParams *buffersink_params = av_buffersink_params_alloc();

 #if FF_API_OLD_VSINK_API
             ret = avfilter_graph_create_filter(&sink, buffersink,
                                                inout->name, NULL,
                                                pix_fmts, lavfi->graph);
 #else
             buffersink_params->pixel_fmts = pix_fmts;
             ret = avfilter_graph_create_filter(&sink, buffersink,
                                                inout->name, NULL,
                                                buffersink_params, lavfi->graph);
 #endif
             av_freep(&buffersink_params);

             if (ret < 0)
                 goto end;
         } else if (type == AVMEDIA_TYPE_AUDIO) {
             enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, -1 };
             const int packing_fmts[] = { AVFILTER_PACKED, -1 };
             const int64_t *chlayouts = avfilter_all_channel_layouts;
             AVABufferSinkParams *abuffersink_params = av_abuffersink_params_alloc();
             abuffersink_params->sample_fmts = sample_fmts;
             abuffersink_params->packing_fmts = packing_fmts;
             abuffersink_params->channel_layouts = chlayouts;

             ret = avfilter_graph_create_filter(&sink, abuffersink,
                                                inout->name, NULL,
                                                abuffersink_params, lavfi->graph);
             av_free(abuffersink_params);
             if (ret < 0)
                 goto end;
         }

         lavfi->sinks[i] = sink;
         if ((ret = avfilter_link(inout->filter_ctx, inout->pad_idx, sink, 0)) < 0)
             FAIL(ret);
     }

     /* configure the graph */
     if ((ret = avfilter_graph_config(lavfi->graph, avctx)) < 0)
         FAIL(ret);

     if (lavfi->dump_graph) {
         char *dump = avfilter_graph_dump(lavfi->graph, lavfi->dump_graph);
         fputs(dump, stderr);
         fflush(stderr);
         av_free(dump);
     }

     /* fill each stream with the information in the corresponding sink */
     for (i = 0; i < avctx->nb_streams; i++) {
         AVFilterLink *link = lavfi->sinks[lavfi->stream_sink_map[i]]->inputs[0];
         AVStream *st = avctx->streams[i];
         st->codec->codec_type = link->type;
         avpriv_set_pts_info(st, 64, link->time_base.num, link->time_base.den);
         if (link->type == AVMEDIA_TYPE_VIDEO) {
             st->codec->codec_id   = CODEC_ID_RAWVIDEO;
             st->codec->pix_fmt    = link->format;
             st->codec->time_base  = link->time_base;
             st->codec->width      = link->w;
             st->codec->height     = link->h;
             st       ->sample_aspect_ratio =
             st->codec->sample_aspect_ratio = link->sample_aspect_ratio;
         } else if (link->type == AVMEDIA_TYPE_AUDIO) {
             st->codec->codec_id    = CODEC_ID_PCM_S16LE;
             st->codec->channels    = av_get_channel_layout_nb_channels(link->channel_layout);
             st->codec->sample_fmt  = link->format;
             st->codec->sample_rate = link->sample_rate;
             st->codec->time_base   = link->time_base;
             st->codec->channel_layout = link->channel_layout;
         }
     }

 end:
     av_free(pix_fmts);
     avfilter_inout_free(&input_links);
     avfilter_inout_free(&output_links);
     if (ret < 0)
         lavfi_read_close(avctx);
     return ret;
 }

 static int lavfi_read_packet(AVFormatContext *avctx, AVPacket *pkt)
 {
     LavfiContext *lavfi = avctx->priv_data;
     double min_pts = DBL_MAX;
     int stream_idx, min_pts_sink_idx = 0;
     AVFilterBufferRef *ref;
     AVPicture pict;
     int ret, i;
     int size = 0;

     /* iterate through all the graph sinks. Select the sink with the
      * minimum PTS */
     for (i = 0; i < avctx->nb_streams; i++) {
         AVRational tb = lavfi->sinks[i]->inputs[0]->time_base;
         double d;
         int ret = av_buffersink_get_buffer_ref(lavfi->sinks[i],
                                                &ref, AV_BUFFERSINK_FLAG_PEEK);
         if (ret < 0)
             return ret;
         d = av_rescale_q(ref->pts, tb, AV_TIME_BASE_Q);
         av_dlog(avctx, "sink_idx:%d time:%f\n", i, d);

         if (d < min_pts) {
             min_pts = d;
             min_pts_sink_idx = i;
         }
     }
     av_dlog(avctx, "min_pts_sink_idx:%i\n", min_pts_sink_idx);

     av_buffersink_get_buffer_ref(lavfi->sinks[min_pts_sink_idx], &ref, 0);
     stream_idx = lavfi->sink_stream_map[min_pts_sink_idx];

     if (ref->video) {
         size = avpicture_get_size(ref->format, ref->video->w, ref->video->h);
         if ((ret = av_new_packet(pkt, size)) < 0)
             return ret;

         memcpy(pict.data,     ref->data,     4*sizeof(ref->data[0]));
         memcpy(pict.linesize, ref->linesize, 4*sizeof(ref->linesize[0]));

         avpicture_layout(&pict, ref->format, ref->video->w,
                          ref->video->h, pkt->data, size);
     } else if (ref->audio) {
         size = ref->audio->nb_samples *
             av_get_bytes_per_sample(ref->format) *
             av_get_channel_layout_nb_channels(ref->audio->channel_layout);
         if ((ret = av_new_packet(pkt, size)) < 0)
             return ret;
         memcpy(pkt->data, ref->data[0], size);
     }

     pkt->stream_index = stream_idx;
     pkt->pts = ref->pts;
     pkt->pos = ref->pos;
     pkt->size = size;
     avfilter_unref_buffer(ref);

     return size;
 }

 #define OFFSET(x) offsetof(LavfiContext, x)

 #define DEC AV_OPT_FLAG_DECODING_PARAM

 static const AVOption options[] = {
     { "graph", "Libavfilter graph", OFFSET(graph_str),  AV_OPT_TYPE_STRING, {.str = NULL }, 0,  0, DEC },
     { "dumpgraph", "Dump graph to stderr", OFFSET(dump_graph), AV_OPT_TYPE_STRING, {.str = NULL}, 0,  0, DEC },
     { NULL },
 };

 static const AVClass lavfi_class = {
     .class_name = "lavfi indev",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };

 AVInputFormat ff_lavfi_demuxer = {
     .name           = "lavfi",
     .long_name      = NULL_IF_CONFIG_SMALL("Libavfilter virtual input device"),
     .priv_data_size = sizeof(LavfiContext),
     .read_header    = lavfi_read_header,
     .read_packet    = lavfi_read_packet,
     .read_close     = lavfi_read_close,
     .flags          = AVFMT_NOFILE,
     .priv_class     = &lavfi_class,
 };
	/*
	* Copyright (c) 2011 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
	* libavfilter virtual input device
	*/

	/* #define DEBUG */

	#include "float.h" /* DBL_MIN, DBL_MAX */

	#include "libavutil/log.h"
	#include "libavutil/mem.h"
	#include "libavutil/opt.h"
	#include "libavutil/parseutils.h"
	#include "libavutil/pixdesc.h"
	#include "libavfilter/avfilter.h"
	#include "libavfilter/avfiltergraph.h"
	#include "libavfilter/buffersink.h"
	#include "libavformat/internal.h"
	#include "avdevice.h"

	typedef struct {
	AVClass *class; ///< class for private options
	char *graph_str;
	char *dump_graph;
	AVFilterGraph *graph;
	AVFilterContext **sinks;
	int *sink_stream_map;
	int *stream_sink_map;
	} LavfiContext;

	static int *create_all_formats(int n)
	{
	int i, j, *fmts, count = 0;

	for (i = 0; i < n; i++)
	if (!(av_pix_fmt_descriptors[i].flags & PIX_FMT_HWACCEL))
	count++;

	if (!(fmts = av_malloc((count+1) * sizeof(int))))
	return NULL;
	for (j = 0, i = 0; i < n; i++) {
	if (!(av_pix_fmt_descriptors[i].flags & PIX_FMT_HWACCEL))
	fmts[j++] = i;
	}
	fmts[j] = -1;
	return fmts;
	}

	av_cold static int lavfi_read_close(AVFormatContext *avctx)
	{
	LavfiContext *lavfi = avctx->priv_data;

	av_freep(&lavfi->sink_stream_map);
	av_freep(&lavfi->stream_sink_map);
	av_freep(&lavfi->sinks);
	avfilter_graph_free(&lavfi->graph);

	return 0;
	}

	av_cold static int lavfi_read_header(AVFormatContext *avctx,
	AVFormatParameters *ap)
	{
	LavfiContext *lavfi = avctx->priv_data;
	AVFilterInOut input_links = NULL, output_links = NULL, *inout;
	AVFilter buffersink, abuffersink;
	int *pix_fmts = create_all_formats(PIX_FMT_NB);
	enum AVMediaType type;
	int ret = 0, i, n;

	#define FAIL(ERR) { ret = ERR; goto end; }

	if (!pix_fmts)
	FAIL(AVERROR(ENOMEM));

	avfilter_register_all();

	buffersink = avfilter_get_by_name("buffersink");
	abuffersink = avfilter_get_by_name("abuffersink");

	if (!lavfi->graph_str)
	lavfi->graph_str = av_strdup(avctx->filename);

	/* parse the graph, create a stream for each open output */
	if (!(lavfi->graph = avfilter_graph_alloc()))
	FAIL(AVERROR(ENOMEM));

	if ((ret = avfilter_graph_parse(lavfi->graph, lavfi->graph_str,
	&input_links, &output_links, avctx)) < 0)
	FAIL(ret);

	if (input_links) {
	av_log(avctx, AV_LOG_ERROR,
	"Open inputs in the filtergraph are not acceptable\n");
	FAIL(AVERROR(EINVAL));
	}

	/* count the outputs */
	for (n = 0, inout = output_links; inout; n++, inout = inout->next);

	if (!(lavfi->sink_stream_map = av_malloc(sizeof(int) * n)))
	FAIL(AVERROR(ENOMEM));
	if (!(lavfi->stream_sink_map = av_malloc(sizeof(int) * n)))
	FAIL(AVERROR(ENOMEM));

	for (i = 0; i < n; i++)
	lavfi->stream_sink_map[i] = -1;

	/* parse the output link names - they need to be of the form out0, out1, ...
	* create a mapping between them and the streams */
	for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
	int stream_idx;
	if (!strcmp(inout->name, "out"))
	stream_idx = 0;
	else if (sscanf(inout->name, "out%d\n", &stream_idx) != 1) {
	av_log(avctx, AV_LOG_ERROR,
	"Invalid outpad name '%s'\n", inout->name);
	FAIL(AVERROR(EINVAL));
	}

	if ((unsigned)stream_idx >= n) {
	av_log(avctx, AV_LOG_ERROR,
	"Invalid index was specified in output '%s', "
	"must be a non-negative value < %d\n",
	inout->name, n);
	FAIL(AVERROR(EINVAL));
	}

	/* is an audio or video output? */
	type = inout->filter_ctx->output_pads[inout->pad_idx].type;
	if (type != AVMEDIA_TYPE_VIDEO && type != AVMEDIA_TYPE_AUDIO) {
	av_log(avctx, AV_LOG_ERROR,
	"Output '%s' is not a video or audio output, not yet supported\n", inout->name);
	FAIL(AVERROR(EINVAL));
	}

	if (lavfi->stream_sink_map[stream_idx] != -1) {
	av_log(avctx, AV_LOG_ERROR,
	"An output with stream index %d was already specified\n",
	stream_idx);
	FAIL(AVERROR(EINVAL));
	}
	lavfi->sink_stream_map[i] = stream_idx;
	lavfi->stream_sink_map[stream_idx] = i;
	}

	/* for each open output create a corresponding stream */
	for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
	AVStream *st;
	if (!(st = avformat_new_stream(avctx, NULL)))
	FAIL(AVERROR(ENOMEM));
	st->id = i;
	}

	/* create a sink for each output and connect them to the graph */
	lavfi->sinks = av_malloc(sizeof(AVFilterContext ) avctx->nb_streams);
	if (!lavfi->sinks)
	FAIL(AVERROR(ENOMEM));

	for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
	AVFilterContext *sink;

	type = inout->filter_ctx->output_pads[inout->pad_idx].type;

	if (type == AVMEDIA_TYPE_VIDEO && ! buffersink \|\|
	type == AVMEDIA_TYPE_AUDIO && ! abuffersink) {
	av_log(avctx, AV_LOG_ERROR, "Missing required buffersink filter, aborting.\n");
	FAIL(AVERROR_FILTER_NOT_FOUND);
	}

	if (type == AVMEDIA_TYPE_VIDEO) {
	AVBufferSinkParams *buffersink_params = av_buffersink_params_alloc();

	#if FF_API_OLD_VSINK_API
	ret = avfilter_graph_create_filter(&sink, buffersink,
	inout->name, NULL,
	pix_fmts, lavfi->graph);
	#else
	buffersink_params->pixel_fmts = pix_fmts;
	ret = avfilter_graph_create_filter(&sink, buffersink,
	inout->name, NULL,
	buffersink_params, lavfi->graph);
	#endif
	av_freep(&buffersink_params);

	if (ret < 0)
	goto end;
	} else if (type == AVMEDIA_TYPE_AUDIO) {
	enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, -1 };
	const int packing_fmts[] = { AVFILTER_PACKED, -1 };
	const int64_t *chlayouts = avfilter_all_channel_layouts;
	AVABufferSinkParams *abuffersink_params = av_abuffersink_params_alloc();
	abuffersink_params->sample_fmts = sample_fmts;
	abuffersink_params->packing_fmts = packing_fmts;
	abuffersink_params->channel_layouts = chlayouts;

	ret = avfilter_graph_create_filter(&sink, abuffersink,
	inout->name, NULL,
	abuffersink_params, lavfi->graph);
	av_free(abuffersink_params);
	if (ret < 0)
	goto end;
	}

	lavfi->sinks[i] = sink;
	if ((ret = avfilter_link(inout->filter_ctx, inout->pad_idx, sink, 0)) < 0)
	FAIL(ret);
	}

	/* configure the graph */
	if ((ret = avfilter_graph_config(lavfi->graph, avctx)) < 0)
	FAIL(ret);

	if (lavfi->dump_graph) {
	char *dump = avfilter_graph_dump(lavfi->graph, lavfi->dump_graph);
	fputs(dump, stderr);
	fflush(stderr);
	av_free(dump);
	}

	/* fill each stream with the information in the corresponding sink */
	for (i = 0; i < avctx->nb_streams; i++) {
	AVFilterLink *link = lavfi->sinks[lavfi->stream_sink_map[i]]->inputs[0];
	AVStream *st = avctx->streams[i];
	st->codec->codec_type = link->type;
	avpriv_set_pts_info(st, 64, link->time_base.num, link->time_base.den);
	if (link->type == AVMEDIA_TYPE_VIDEO) {
	st->codec->codec_id = CODEC_ID_RAWVIDEO;
	st->codec->pix_fmt = link->format;
	st->codec->time_base = link->time_base;
	st->codec->width = link->w;
	st->codec->height = link->h;
	st ->sample_aspect_ratio =
	st->codec->sample_aspect_ratio = link->sample_aspect_ratio;
	} else if (link->type == AVMEDIA_TYPE_AUDIO) {
	st->codec->codec_id = CODEC_ID_PCM_S16LE;
	st->codec->channels = av_get_channel_layout_nb_channels(link->channel_layout);
	st->codec->sample_fmt = link->format;
	st->codec->sample_rate = link->sample_rate;
	st->codec->time_base = link->time_base;
	st->codec->channel_layout = link->channel_layout;
	}
	}

	end:
	av_free(pix_fmts);
	avfilter_inout_free(&input_links);
	avfilter_inout_free(&output_links);
	if (ret < 0)
	lavfi_read_close(avctx);
	return ret;
	}

	static int lavfi_read_packet(AVFormatContext avctx, AVPacket pkt)
	{
	LavfiContext *lavfi = avctx->priv_data;
	double min_pts = DBL_MAX;
	int stream_idx, min_pts_sink_idx = 0;
	AVFilterBufferRef *ref;
	AVPicture pict;
	int ret, i;
	int size = 0;

	/* iterate through all the graph sinks. Select the sink with the
	* minimum PTS */
	for (i = 0; i < avctx->nb_streams; i++) {
	AVRational tb = lavfi->sinks[i]->inputs[0]->time_base;
	double d;
	int ret = av_buffersink_get_buffer_ref(lavfi->sinks[i],
	&ref, AV_BUFFERSINK_FLAG_PEEK);
	if (ret < 0)
	return ret;
	d = av_rescale_q(ref->pts, tb, AV_TIME_BASE_Q);
	av_dlog(avctx, "sink_idx:%d time:%f\n", i, d);

	if (d < min_pts) {
	min_pts = d;
	min_pts_sink_idx = i;
	}
	}
	av_dlog(avctx, "min_pts_sink_idx:%i\n", min_pts_sink_idx);

	av_buffersink_get_buffer_ref(lavfi->sinks[min_pts_sink_idx], &ref, 0);
	stream_idx = lavfi->sink_stream_map[min_pts_sink_idx];

	if (ref->video) {
	size = avpicture_get_size(ref->format, ref->video->w, ref->video->h);
	if ((ret = av_new_packet(pkt, size)) < 0)
	return ret;

	memcpy(pict.data, ref->data, 4*sizeof(ref->data[0]));
	memcpy(pict.linesize, ref->linesize, 4*sizeof(ref->linesize[0]));

	avpicture_layout(&pict, ref->format, ref->video->w,
	ref->video->h, pkt->data, size);
	} else if (ref->audio) {
	size = ref->audio->nb_samples *
	av_get_bytes_per_sample(ref->format) *
	av_get_channel_layout_nb_channels(ref->audio->channel_layout);
	if ((ret = av_new_packet(pkt, size)) < 0)
	return ret;
	memcpy(pkt->data, ref->data[0], size);
	}

	pkt->stream_index = stream_idx;
	pkt->pts = ref->pts;
	pkt->pos = ref->pos;
	pkt->size = size;
	avfilter_unref_buffer(ref);

	return size;
	}

	#define OFFSET(x) offsetof(LavfiContext, x)

	#define DEC AV_OPT_FLAG_DECODING_PARAM

	static const AVOption options[] = {
	{ "graph", "Libavfilter graph", OFFSET(graph_str), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
	{ "dumpgraph", "Dump graph to stderr", OFFSET(dump_graph), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
	{ NULL },
	};

	static const AVClass lavfi_class = {
	.class_name = "lavfi indev",
	.item_name = av_default_item_name,
	.option = options,
	.version = LIBAVUTIL_VERSION_INT,
	};

	AVInputFormat ff_lavfi_demuxer = {
	.name = "lavfi",
	.long_name = NULL_IF_CONFIG_SMALL("Libavfilter virtual input device"),
	.priv_data_size = sizeof(LavfiContext),
	.read_header = lavfi_read_header,
	.read_packet = lavfi_read_packet,
	.read_close = lavfi_read_close,
	.flags = AVFMT_NOFILE,
	.priv_class = &lavfi_class,
	};