ffmpeg/libavformat/segment.c

414 lines
13 KiB
C

/*
* Generic segmenter
* Copyright (c) 2011, Luca Barbato
*
* 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
*/
#include <float.h>
#include "avformat.h"
#include "internal.h"
#include "libavutil/avassert.h"
#include "libavutil/log.h"
#include "libavutil/opt.h"
#include "libavutil/avstring.h"
#include "libavutil/parseutils.h"
#include "libavutil/mathematics.h"
typedef enum {
LIST_TYPE_FLAT = 0,
LIST_TYPE_EXT,
LIST_TYPE_NB,
} ListType;
typedef struct {
const AVClass *class; /**< Class for private options. */
int number;
AVFormatContext *avf;
char *format; ///< format to use for output segment files
char *list; ///< filename for the segment list file
int list_size; ///< number of entries for the segment list file
ListType list_type; ///< set the list type
AVIOContext *list_pb; ///< list file put-byte context
int wrap; ///< number after which the index wraps
char *time_str; ///< segment duration specification string
int64_t time; ///< segment duration
char *times_str; ///< segment times specification string
int64_t *times; ///< list of segment interval specification
int nb_times; ///< number of elments in the times array
char *time_delta_str; ///< approximation value duration used for the segment times
int64_t time_delta;
int has_video;
double start_time, end_time;
} SegmentContext;
static int segment_start(AVFormatContext *s)
{
SegmentContext *seg = s->priv_data;
AVFormatContext *oc = seg->avf;
int err = 0;
if (seg->wrap)
seg->number %= seg->wrap;
if (av_get_frame_filename(oc->filename, sizeof(oc->filename),
s->filename, seg->number++) < 0) {
av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", s->filename);
return AVERROR(EINVAL);
}
if ((err = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,
&s->interrupt_callback, NULL)) < 0)
return err;
if (!oc->priv_data && oc->oformat->priv_data_size > 0) {
oc->priv_data = av_mallocz(oc->oformat->priv_data_size);
if (!oc->priv_data) {
avio_close(oc->pb);
return AVERROR(ENOMEM);
}
if (oc->oformat->priv_class) {
*(const AVClass**)oc->priv_data = oc->oformat->priv_class;
av_opt_set_defaults(oc->priv_data);
}
}
if ((err = oc->oformat->write_header(oc)) < 0) {
goto fail;
}
return 0;
fail:
av_log(oc, AV_LOG_ERROR, "Failure occurred when starting segment '%s'\n",
oc->filename);
avio_close(oc->pb);
av_freep(&oc->priv_data);
return err;
}
static int segment_end(AVFormatContext *s)
{
SegmentContext *seg = s->priv_data;
AVFormatContext *oc = seg->avf;
int ret = 0;
if (oc->oformat->write_trailer)
ret = oc->oformat->write_trailer(oc);
if (ret < 0)
av_log(s, AV_LOG_ERROR, "Failure occurred when ending segment '%s'\n",
oc->filename);
if (seg->list) {
if (seg->list_size && !(seg->number % seg->list_size)) {
avio_close(seg->list_pb);
if ((ret = avio_open2(&seg->list_pb, seg->list, AVIO_FLAG_WRITE,
&s->interrupt_callback, NULL)) < 0)
goto end;
}
if (seg->list_type == LIST_TYPE_FLAT) {
avio_printf(seg->list_pb, "%s\n", oc->filename);
} else if (seg->list_type == LIST_TYPE_EXT) {
avio_printf(seg->list_pb, "%s,%f,%f\n", oc->filename, seg->start_time, seg->end_time);
}
avio_flush(seg->list_pb);
}
end:
avio_close(oc->pb);
if (oc->oformat->priv_class)
av_opt_free(oc->priv_data);
av_freep(&oc->priv_data);
return ret;
}
static int parse_times(void *log_ctx, int64_t **times, int *nb_times,
const char *times_str)
{
char *p;
int i, ret = 0;
char *times_str1 = av_strdup(times_str);
char *saveptr = NULL;
if (!times_str1)
return AVERROR(ENOMEM);
#define FAIL(err) ret = err; goto end
*nb_times = 1;
for (p = times_str1; *p; p++)
if (*p == ',')
(*nb_times)++;
*times = av_malloc(sizeof(**times) * *nb_times);
if (!*times) {
av_log(log_ctx, AV_LOG_ERROR, "Could not allocate forced times array\n");
FAIL(AVERROR(ENOMEM));
}
p = times_str1;
for (i = 0; i < *nb_times; i++) {
int64_t t;
char *tstr = av_strtok(p, ",", &saveptr);
av_assert0(tstr);
p = NULL;
ret = av_parse_time(&t, tstr, 1);
if (ret < 0) {
av_log(log_ctx, AV_LOG_ERROR,
"Invalid time duration specification in %s\n", p);
FAIL(AVERROR(EINVAL));
}
(*times)[i] = t;
/* check on monotonicity */
if (i && (*times)[i-1] > (*times)[i]) {
av_log(log_ctx, AV_LOG_ERROR,
"Specified time %f is greater than the following time %f\n",
(float)((*times)[i])/1000000, (float)((*times)[i-1])/1000000);
FAIL(AVERROR(EINVAL));
}
}
end:
av_free(times_str1);
return ret;
}
static int seg_write_header(AVFormatContext *s)
{
SegmentContext *seg = s->priv_data;
AVFormatContext *oc;
int ret, i;
seg->number = 0;
if (seg->time_str && seg->times_str) {
av_log(s, AV_LOG_ERROR,
"segment_time and segment_times options are mutually exclusive, select just one of them\n");
return AVERROR(EINVAL);
}
if (seg->times_str) {
if ((ret = parse_times(s, &seg->times, &seg->nb_times, seg->times_str)) < 0)
return ret;
} else {
/* set default value if not specified */
if (!seg->time_str)
seg->time_str = av_strdup("2");
if ((ret = av_parse_time(&seg->time, seg->time_str, 1)) < 0) {
av_log(s, AV_LOG_ERROR,
"Invalid time duration specification '%s' for segment_time option\n",
seg->time_str);
return ret;
}
}
if (seg->time_delta_str) {
if ((ret = av_parse_time(&seg->time_delta, seg->time_delta_str, 1)) < 0) {
av_log(s, AV_LOG_ERROR,
"Invalid time duration specification '%s' for delta option\n",
seg->time_delta_str);
return ret;
}
}
oc = avformat_alloc_context();
if (!oc)
return AVERROR(ENOMEM);
if (seg->list)
if ((ret = avio_open2(&seg->list_pb, seg->list, AVIO_FLAG_WRITE,
&s->interrupt_callback, NULL)) < 0)
goto fail;
for (i = 0; i< s->nb_streams; i++)
seg->has_video +=
(s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO);
if (seg->has_video > 1)
av_log(s, AV_LOG_WARNING,
"More than a single video stream present, "
"expect issues decoding it.\n");
oc->oformat = av_guess_format(seg->format, s->filename, NULL);
if (!oc->oformat) {
ret = AVERROR_MUXER_NOT_FOUND;
goto fail;
}
if (oc->oformat->flags & AVFMT_NOFILE) {
av_log(s, AV_LOG_ERROR, "format %s not supported.\n",
oc->oformat->name);
ret = AVERROR(EINVAL);
goto fail;
}
seg->avf = oc;
oc->streams = s->streams;
oc->nb_streams = s->nb_streams;
if (av_get_frame_filename(oc->filename, sizeof(oc->filename),
s->filename, seg->number++) < 0) {
ret = AVERROR(EINVAL);
goto fail;
}
if ((ret = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,
&s->interrupt_callback, NULL)) < 0)
goto fail;
if ((ret = avformat_write_header(oc, NULL)) < 0) {
avio_close(oc->pb);
goto fail;
}
fail:
if (ret) {
if (oc) {
oc->streams = NULL;
oc->nb_streams = 0;
avformat_free_context(oc);
}
if (seg->list)
avio_close(seg->list_pb);
}
return ret;
}
static int seg_write_packet(AVFormatContext *s, AVPacket *pkt)
{
SegmentContext *seg = s->priv_data;
AVFormatContext *oc = seg->avf;
AVStream *st = oc->streams[pkt->stream_index];
int64_t end_pts;
int ret;
if (seg->times) {
end_pts = seg->number <= seg->nb_times ? seg->times[seg->number-1] : INT64_MAX;
} else {
end_pts = seg->time * seg->number;
}
/* if the segment has video, start a new segment *only* with a key video frame */
if ((st->codec->codec_type == AVMEDIA_TYPE_VIDEO || !seg->has_video) &&
av_compare_ts(pkt->pts, st->time_base,
end_pts-seg->time_delta, AV_TIME_BASE_Q) >= 0 &&
pkt->flags & AV_PKT_FLAG_KEY) {
av_log(s, AV_LOG_DEBUG, "Next segment starts with packet stream:%d pts:%"PRId64" pts_time:%f\n",
pkt->stream_index, pkt->pts, pkt->pts * av_q2d(st->time_base));
if ((ret = segment_end(s)) < 0 || (ret = segment_start(s)) < 0)
goto fail;
seg->start_time = (double)pkt->pts * av_q2d(st->time_base);
} else if (pkt->pts != AV_NOPTS_VALUE) {
seg->end_time = FFMAX(seg->end_time,
(double)(pkt->pts + pkt->duration) * av_q2d(st->time_base));
}
ret = oc->oformat->write_packet(oc, pkt);
fail:
if (ret < 0) {
oc->streams = NULL;
oc->nb_streams = 0;
if (seg->list)
avio_close(seg->list_pb);
avformat_free_context(oc);
}
return ret;
}
static int seg_write_trailer(struct AVFormatContext *s)
{
SegmentContext *seg = s->priv_data;
AVFormatContext *oc = seg->avf;
int ret = segment_end(s);
if (seg->list)
avio_close(seg->list_pb);
av_opt_free(seg);
av_freep(&seg->times);
oc->streams = NULL;
oc->nb_streams = 0;
avformat_free_context(oc);
return ret;
}
#define OFFSET(x) offsetof(SegmentContext, x)
#define E AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "segment_format", "set container format used for the segments", OFFSET(format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E },
{ "segment_list", "set the segment list filename", OFFSET(list), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E },
{ "segment_list_size", "set the maximum number of playlist entries", OFFSET(list_size), AV_OPT_TYPE_INT, {.dbl = 5}, 0, INT_MAX, E },
{ "segment_list_type", "set the segment list type", OFFSET(list_type), AV_OPT_TYPE_INT, {.dbl = LIST_TYPE_FLAT}, 0, LIST_TYPE_NB-1, E, "list_type" },
{ "flat", "flat format", 0, AV_OPT_TYPE_CONST, {.dbl=LIST_TYPE_FLAT }, INT_MIN, INT_MAX, 0, "list_type" },
{ "ext", "extended format", 0, AV_OPT_TYPE_CONST, {.dbl=LIST_TYPE_EXT }, INT_MIN, INT_MAX, 0, "list_type" },
{ "segment_time", "set segment duration", OFFSET(time_str),AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E },
{ "segment_time_delta","set approximation value used for the segment times", OFFSET(time_delta_str), AV_OPT_TYPE_STRING, {.str = "0"}, 0, 0, E },
{ "segment_times", "set segment split time points", OFFSET(times_str),AV_OPT_TYPE_STRING,{.str = NULL}, 0, 0, E },
{ "segment_wrap", "set number after which the index wraps", OFFSET(wrap), AV_OPT_TYPE_INT, {.dbl = 0}, 0, INT_MAX, E },
{ NULL },
};
static const AVClass seg_class = {
.class_name = "segment muxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_segment_muxer = {
.name = "segment",
.long_name = NULL_IF_CONFIG_SMALL("segment"),
.priv_data_size = sizeof(SegmentContext),
.flags = AVFMT_GLOBALHEADER | AVFMT_NOFILE,
.write_header = seg_write_header,
.write_packet = seg_write_packet,
.write_trailer = seg_write_trailer,
.priv_class = &seg_class,
};
static const AVClass sseg_class = {
.class_name = "stream_segment muxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_stream_segment_muxer = {
.name = "stream_segment,ssegment",
.long_name = NULL_IF_CONFIG_SMALL("streaming segment muxer"),
.priv_data_size = sizeof(SegmentContext),
.flags = AVFMT_NOFILE,
.write_header = seg_write_header,
.write_packet = seg_write_packet,
.write_trailer = seg_write_trailer,
.priv_class = &sseg_class,
};