[FFmpeg-cvslog] r24834 - in trunk: Changelog doc/general.texi libavformat/Makefile libavformat/allformats.c libavformat/applehttp.c
mstorsjo
subversion
Thu Aug 19 16:54:37 CEST 2010
Author: mstorsjo
Date: Thu Aug 19 16:54:37 2010
New Revision: 24834
Log:
Add Apple HTTP Live Streaming demuxer
Added:
trunk/libavformat/applehttp.c
Modified:
trunk/Changelog
trunk/doc/general.texi
trunk/libavformat/Makefile
trunk/libavformat/allformats.c
Modified: trunk/Changelog
==============================================================================
--- trunk/Changelog Thu Aug 19 16:50:40 2010 (r24833)
+++ trunk/Changelog Thu Aug 19 16:54:37 2010 (r24834)
@@ -30,6 +30,7 @@ version <next>:
- RTP depacketization of MP4A-LATM
- RTP packetization and depacketization of VP8
- hflip filter
+- Apple HTTP Live Streaming demuxer
version 0.6:
Modified: trunk/doc/general.texi
==============================================================================
--- trunk/doc/general.texi Thu Aug 19 16:50:40 2010 (r24833)
+++ trunk/doc/general.texi Thu Aug 19 16:54:37 2010 (r24834)
@@ -49,6 +49,7 @@ library:
@item American Laser Games MM @tab @tab X
@tab Multimedia format used in games like Mad Dog McCree.
@item 3GPP AMR @tab X @tab X
+ at item Apple HTTP Live Streaming @tab @tab X
@item ASF @tab X @tab X
@item AVI @tab X @tab X
@item AVISynth @tab @tab X
Modified: trunk/libavformat/Makefile
==============================================================================
--- trunk/libavformat/Makefile Thu Aug 19 16:50:40 2010 (r24833)
+++ trunk/libavformat/Makefile Thu Aug 19 16:54:37 2010 (r24834)
@@ -28,6 +28,7 @@ OBJS-$(CONFIG_AMR_MUXER)
OBJS-$(CONFIG_ANM_DEMUXER) += anm.o
OBJS-$(CONFIG_APC_DEMUXER) += apc.o
OBJS-$(CONFIG_APE_DEMUXER) += ape.o apetag.o
+OBJS-$(CONFIG_APPLEHTTP_DEMUXER) += applehttp.o
OBJS-$(CONFIG_ASF_DEMUXER) += asfdec.o asf.o asfcrypt.o \
riff.o avlanguage.o
OBJS-$(CONFIG_ASF_MUXER) += asfenc.o asf.o riff.o
Modified: trunk/libavformat/allformats.c
==============================================================================
--- trunk/libavformat/allformats.c Thu Aug 19 16:50:40 2010 (r24833)
+++ trunk/libavformat/allformats.c Thu Aug 19 16:54:37 2010 (r24834)
@@ -56,6 +56,7 @@ void av_register_all(void)
REGISTER_DEMUXER (ANM, anm);
REGISTER_DEMUXER (APC, apc);
REGISTER_DEMUXER (APE, ape);
+ REGISTER_DEMUXER (APPLEHTTP, applehttp);
REGISTER_MUXDEMUX (ASF, asf);
REGISTER_MUXDEMUX (ASS, ass);
REGISTER_MUXER (ASF_STREAM, asf_stream);
Added: trunk/libavformat/applehttp.c
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ trunk/libavformat/applehttp.c Thu Aug 19 16:54:37 2010 (r24834)
@@ -0,0 +1,578 @@
+/*
+ * Apple HTTP Live Streaming demuxer
+ * Copyright (c) 2010 Martin Storsjo
+ *
+ * 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
+ * Apple HTTP Live Streaming demuxer
+ * http://tools.ietf.org/html/draft-pantos-http-live-streaming
+ */
+
+#include "libavutil/avstring.h"
+#include "avformat.h"
+#include "internal.h"
+#include <unistd.h>
+
+/*
+ * An apple http stream consists of a playlist with media segment files,
+ * played sequentially. There may be several playlists with the same
+ * video content, in different bandwidth variants, that are played in
+ * parallel (preferrably only one bandwidth variant at a time). In this case,
+ * the user supplied the url to a main playlist that only lists the variant
+ * playlists.
+ *
+ * If the main playlist doesn't point at any variants, we still create
+ * one anonymous toplevel variant for this, to maintain the structure.
+ */
+
+struct segment {
+ int duration;
+ char url[MAX_URL_SIZE];
+};
+
+/*
+ * Each variant has its own demuxer. If it currently is active,
+ * it has an open ByteIOContext too, and potentially an AVPacket
+ * containing the next packet from this stream.
+ */
+struct variant {
+ int bandwidth;
+ char url[MAX_URL_SIZE];
+ ByteIOContext *pb;
+ AVFormatContext *ctx;
+ AVPacket pkt;
+ int stream_offset;
+
+ int start_seq_no;
+ int n_segments;
+ struct segment **segments;
+ int needed;
+};
+
+typedef struct AppleHTTPContext {
+ int target_duration;
+ int finished;
+ int n_variants;
+ struct variant **variants;
+ int cur_seq_no;
+ int64_t last_load_time;
+ int64_t last_packet_dts;
+ int max_start_seq, min_end_seq;
+} AppleHTTPContext;
+
+static int read_chomp_line(ByteIOContext *s, char *buf, int maxlen)
+{
+ int len = ff_get_line(s, buf, maxlen);
+ while (len > 0 && isspace(buf[len - 1]))
+ buf[--len] = '\0';
+ return len;
+}
+
+static void make_absolute_url(char *buf, int size, const char *base,
+ const char *rel)
+{
+ char *sep;
+ if (!base || strstr(rel, "://")) {
+ av_strlcpy(buf, rel, size);
+ return;
+ }
+ if (base != buf)
+ av_strlcpy(buf, base, size);
+ sep = strrchr(buf, '/');
+ if (sep)
+ sep[1] = '\0';
+ while (av_strstart(rel, "../", NULL)) {
+ if (sep) {
+ sep[0] = '\0';
+ sep = strrchr(buf, '/');
+ if (sep)
+ sep[1] = '\0';
+ }
+ rel += 3;
+ }
+ av_strlcat(buf, rel, size);
+}
+
+static void free_segment_list(struct variant *var)
+{
+ int i;
+ for (i = 0; i < var->n_segments; i++)
+ av_free(var->segments[i]);
+ av_freep(&var->segments);
+ var->n_segments = 0;
+}
+
+static void free_variant_list(AppleHTTPContext *c)
+{
+ int i;
+ for (i = 0; i < c->n_variants; i++) {
+ struct variant *var = c->variants[i];
+ free_segment_list(var);
+ av_free_packet(&var->pkt);
+ if (var->pb)
+ url_fclose(var->pb);
+ if (var->ctx) {
+ var->ctx->pb = NULL;
+ av_close_input_file(var->ctx);
+ }
+ av_free(var);
+ }
+ av_freep(&c->variants);
+ c->n_variants = 0;
+}
+
+/*
+ * Used to reset a statically allocated AVPacket to a clean slate,
+ * containing no data.
+ */
+static void reset_packet(AVPacket *pkt)
+{
+ av_init_packet(pkt);
+ pkt->data = NULL;
+}
+
+static struct variant *new_variant(AppleHTTPContext *c, int bandwidth,
+ const char *url, const char *base)
+{
+ struct variant *var = av_mallocz(sizeof(struct variant));
+ if (!var)
+ return NULL;
+ reset_packet(&var->pkt);
+ var->bandwidth = bandwidth;
+ make_absolute_url(var->url, sizeof(var->url), base, url);
+ dynarray_add(&c->variants, &c->n_variants, var);
+ return var;
+}
+
+struct variant_info {
+ char bandwidth[20];
+};
+
+static void handle_variant_args(struct variant_info *info, const char *key,
+ int key_len, char **dest, int *dest_len)
+{
+ if (strncmp(key, "BANDWIDTH", key_len)) {
+ *dest = info->bandwidth;
+ *dest_len = sizeof(info->bandwidth);
+ }
+}
+
+static int parse_playlist(AppleHTTPContext *c, const char *url,
+ struct variant *var, ByteIOContext *in)
+{
+ int ret = 0, duration = 0, is_segment = 0, is_variant = 0, bandwidth = 0;
+ char line[1024];
+ const char *ptr;
+ int close_in = 0;
+
+ if (!in) {
+ close_in = 1;
+ if ((ret = url_fopen(&in, url, URL_RDONLY)) < 0)
+ return ret;
+ }
+
+ read_chomp_line(in, line, sizeof(line));
+ if (strcmp(line, "#EXTM3U")) {
+ ret = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ if (var)
+ free_segment_list(var);
+ c->finished = 0;
+ while (!url_feof(in)) {
+ read_chomp_line(in, line, sizeof(line));
+ if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {
+ struct variant_info info = {{0}};
+ is_variant = 1;
+ ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args,
+ &info);
+ bandwidth = atoi(info.bandwidth);
+ } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
+ c->target_duration = atoi(ptr);
+ } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
+ if (!var) {
+ var = new_variant(c, 0, url, NULL);
+ if (!var) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ }
+ var->start_seq_no = atoi(ptr);
+ } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {
+ c->finished = 1;
+ } else if (av_strstart(line, "#EXTINF:", &ptr)) {
+ is_segment = 1;
+ duration = atoi(ptr);
+ } else if (av_strstart(line, "#", NULL)) {
+ continue;
+ } else if (line[0]) {
+ if (is_variant) {
+ if (!new_variant(c, bandwidth, line, url)) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ is_variant = 0;
+ bandwidth = 0;
+ }
+ if (is_segment) {
+ struct segment *seg;
+ if (!var) {
+ var = new_variant(c, 0, url, NULL);
+ if (!var) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ }
+ seg = av_malloc(sizeof(struct segment));
+ if (!seg) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ seg->duration = duration;
+ make_absolute_url(seg->url, sizeof(seg->url), url, line);
+ dynarray_add(&var->segments, &var->n_segments, seg);
+ is_segment = 0;
+ }
+ }
+ }
+ c->last_load_time = av_gettime();
+
+fail:
+ if (close_in)
+ url_fclose(in);
+ return ret;
+}
+
+static int applehttp_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+ AppleHTTPContext *c = s->priv_data;
+ int ret = 0, i, j, stream_offset = 0;
+
+ if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
+ goto fail;
+
+ if (c->n_variants == 0) {
+ av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
+ ret = AVERROR_EOF;
+ goto fail;
+ }
+ /* If the playlist only contained variants, parse each individual
+ * variant playlist. */
+ if (c->n_variants > 1 || c->variants[0]->n_segments == 0) {
+ for (i = 0; i < c->n_variants; i++) {
+ struct variant *v = c->variants[i];
+ if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
+ goto fail;
+ }
+ }
+
+ if (c->variants[0]->n_segments == 0) {
+ av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
+ ret = AVERROR_EOF;
+ goto fail;
+ }
+
+ /* If this isn't a live stream, calculate the total duration of the
+ * stream. */
+ if (c->finished) {
+ int duration = 0;
+ for (i = 0; i < c->variants[0]->n_segments; i++)
+ duration += c->variants[0]->segments[i]->duration;
+ s->duration = duration * AV_TIME_BASE;
+ }
+
+ c->min_end_seq = INT_MAX;
+ /* Open the demuxer for each variant */
+ for (i = 0; i < c->n_variants; i++) {
+ struct variant *v = c->variants[i];
+ if (v->n_segments == 0)
+ continue;
+ c->max_start_seq = FFMAX(c->max_start_seq, v->start_seq_no);
+ c->min_end_seq = FFMIN(c->min_end_seq, v->start_seq_no +
+ v->n_segments);
+ ret = av_open_input_file(&v->ctx, v->segments[0]->url, NULL, 0, NULL);
+ if (ret < 0)
+ goto fail;
+ url_fclose(v->ctx->pb);
+ v->ctx->pb = NULL;
+ v->stream_offset = stream_offset;
+ /* Create new AVStreams for each stream in this variant */
+ for (j = 0; j < v->ctx->nb_streams; j++) {
+ AVStream *st = av_new_stream(s, i);
+ if (!st) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ avcodec_copy_context(st->codec, v->ctx->streams[j]->codec);
+ }
+ stream_offset += v->ctx->nb_streams;
+ }
+ c->last_packet_dts = AV_NOPTS_VALUE;
+
+ c->cur_seq_no = c->max_start_seq;
+ /* If this is a live stream with more than 3 segments, start at the
+ * third last segment. */
+ if (!c->finished && c->min_end_seq - c->max_start_seq > 3)
+ c->cur_seq_no = c->min_end_seq - 2;
+
+ return 0;
+fail:
+ free_variant_list(c);
+ return ret;
+}
+
+static int open_variant(AppleHTTPContext *c, struct variant *var, int skip)
+{
+ int ret;
+
+ if (c->cur_seq_no < var->start_seq_no) {
+ av_log(NULL, AV_LOG_WARNING,
+ "seq %d not available in variant %s, skipping\n",
+ var->start_seq_no, var->url);
+ return 0;
+ }
+ if (c->cur_seq_no - var->start_seq_no >= var->n_segments)
+ return c->finished ? AVERROR_EOF : 0;
+ ret = url_fopen(&var->pb,
+ var->segments[c->cur_seq_no - var->start_seq_no]->url,
+ URL_RDONLY);
+ if (ret < 0)
+ return ret;
+ var->ctx->pb = var->pb;
+ /* If this is a new segment in parallel with another one already opened,
+ * skip ahead so they're all at the same dts. */
+ if (skip && c->last_packet_dts != AV_NOPTS_VALUE) {
+ while (1) {
+ ret = av_read_frame(var->ctx, &var->pkt);
+ if (ret < 0) {
+ if (ret == AVERROR_EOF) {
+ reset_packet(&var->pkt);
+ return 0;
+ }
+ return ret;
+ }
+ if (var->pkt.dts >= c->last_packet_dts)
+ break;
+ av_free_packet(&var->pkt);
+ }
+ }
+ return 0;
+}
+
+static int applehttp_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ AppleHTTPContext *c = s->priv_data;
+ int ret, i, minvariant = -1, first = 1, needed = 0, changed = 0,
+ variants = 0;
+
+ /* Recheck the discard flags - which streams are desired at the moment */
+ for (i = 0; i < c->n_variants; i++)
+ c->variants[i]->needed = 0;
+ for (i = 0; i < s->nb_streams; i++) {
+ AVStream *st = s->streams[i];
+ struct variant *var = c->variants[s->streams[i]->id];
+ if (st->discard < AVDISCARD_ALL) {
+ var->needed = 1;
+ needed++;
+ }
+ /* Copy the discard flag to the chained demuxer, to indicate which
+ * streams are desired. */
+ var->ctx->streams[i - var->stream_offset]->discard = st->discard;
+ }
+ if (!needed)
+ return AVERROR_EOF;
+start:
+ for (i = 0; i < c->n_variants; i++) {
+ struct variant *var = c->variants[i];
+ /* Close unneeded streams, open newly requested streams */
+ if (var->pb && !var->needed) {
+ av_log(s, AV_LOG_DEBUG,
+ "Closing variant stream %d, no longer needed\n", i);
+ av_free_packet(&var->pkt);
+ reset_packet(&var->pkt);
+ url_fclose(var->pb);
+ var->pb = NULL;
+ changed = 1;
+ } else if (!var->pb && var->needed) {
+ if (first)
+ av_log(s, AV_LOG_DEBUG, "Opening variant stream %d\n", i);
+ if (first && !c->finished)
+ if ((ret = parse_playlist(c, var->url, var, NULL)) < 0)
+ return ret;
+ ret = open_variant(c, var, first);
+ if (ret < 0)
+ return ret;
+ changed = 1;
+ }
+ /* Count the number of open variants */
+ if (var->pb)
+ variants++;
+ /* Make sure we've got one buffered packet from each open variant
+ * stream */
+ if (var->pb && !var->pkt.data) {
+ ret = av_read_frame(var->ctx, &var->pkt);
+ if (ret < 0) {
+ if (!url_feof(var->pb))
+ return ret;
+ reset_packet(&var->pkt);
+ }
+ }
+ /* Check if this stream has the packet with the lowest dts */
+ if (var->pkt.data) {
+ if (minvariant < 0 ||
+ var->pkt.dts < c->variants[minvariant]->pkt.dts)
+ minvariant = i;
+ }
+ }
+ if (first && changed)
+ av_log(s, AV_LOG_INFO, "Receiving %d variant streams\n", variants);
+ /* If we got a packet, return it */
+ if (minvariant >= 0) {
+ *pkt = c->variants[minvariant]->pkt;
+ pkt->stream_index += c->variants[minvariant]->stream_offset;
+ reset_packet(&c->variants[minvariant]->pkt);
+ c->last_packet_dts = pkt->dts;
+ return 0;
+ }
+ /* No more packets - eof reached in all variant streams, close the
+ * current segments. */
+ for (i = 0; i < c->n_variants; i++) {
+ struct variant *var = c->variants[i];
+ if (var->pb) {
+ url_fclose(var->pb);
+ var->pb = NULL;
+ }
+ }
+ /* Indicate that we're opening the next segment, not opening a new
+ * variant stream in parallel, so we shouldn't try to skip ahead. */
+ first = 0;
+ c->cur_seq_no++;
+reload:
+ if (!c->finished) {
+ /* If this is a live stream and target_duration has elapsed since
+ * the last playlist reload, reload the variant playlists now. */
+ int64_t now = av_gettime();
+ if (now - c->last_load_time >= c->target_duration*1000000) {
+ c->max_start_seq = 0;
+ c->min_end_seq = INT_MAX;
+ for (i = 0; i < c->n_variants; i++) {
+ struct variant *var = c->variants[i];
+ if (var->needed) {
+ if ((ret = parse_playlist(c, var->url, var, NULL)) < 0)
+ return ret;
+ c->max_start_seq = FFMAX(c->max_start_seq,
+ var->start_seq_no);
+ c->min_end_seq = FFMIN(c->min_end_seq,
+ var->start_seq_no + var->n_segments);
+ }
+ }
+ }
+ }
+ if (c->cur_seq_no < c->max_start_seq) {
+ av_log(NULL, AV_LOG_WARNING,
+ "skipping %d segments ahead, expired from playlists\n",
+ c->max_start_seq - c->cur_seq_no);
+ c->cur_seq_no = c->max_start_seq;
+ }
+ /* If more segments exit, open the next one */
+ if (c->cur_seq_no < c->min_end_seq)
+ goto start;
+ /* We've reached the end of the playlists - return eof if this is a
+ * non-live stream, wait until the next playlist reload if it is live. */
+ if (c->finished)
+ return AVERROR_EOF;
+ while (av_gettime() - c->last_load_time < c->target_duration*1000000) {
+ if (url_interrupt_cb())
+ return AVERROR(EINTR);
+ usleep(100*1000);
+ }
+ /* Enough time has elapsed since the last reload */
+ goto reload;
+}
+
+static int applehttp_close(AVFormatContext *s)
+{
+ AppleHTTPContext *c = s->priv_data;
+
+ free_variant_list(c);
+ return 0;
+}
+
+static int applehttp_read_seek(AVFormatContext *s, int stream_index,
+ int64_t timestamp, int flags)
+{
+ AppleHTTPContext *c = s->priv_data;
+ int pos = 0, i;
+ struct variant *var = c->variants[0];
+
+ if ((flags & AVSEEK_FLAG_BYTE) || !c->finished)
+ return AVERROR(ENOSYS);
+
+ /* Reset the variants */
+ c->last_packet_dts = AV_NOPTS_VALUE;
+ for (i = 0; i < c->n_variants; i++) {
+ struct variant *var = c->variants[i];
+ if (var->pb) {
+ url_fclose(var->pb);
+ var->pb = NULL;
+ }
+ av_free_packet(&var->pkt);
+ reset_packet(&var->pkt);
+ }
+
+ timestamp = av_rescale_rnd(timestamp, 1, stream_index >= 0 ?
+ s->streams[stream_index]->time_base.den :
+ AV_TIME_BASE, flags & AVSEEK_FLAG_BACKWARD ?
+ AV_ROUND_DOWN : AV_ROUND_UP);
+ /* Locate the segment that contains the target timestamp */
+ for (i = 0; i < var->n_segments; i++) {
+ if (timestamp >= pos && timestamp < pos + var->segments[i]->duration) {
+ c->cur_seq_no = var->start_seq_no + i;
+ return 0;
+ }
+ pos += var->segments[i]->duration;
+ }
+ return AVERROR(EIO);
+}
+
+static int applehttp_probe(AVProbeData *p)
+{
+ /* Require #EXTM3U at the start, and either one of the ones below
+ * somewhere for a proper match. */
+ if (strncmp(p->buf, "#EXTM3U", 7))
+ return 0;
+ if (strstr(p->buf, "#EXT-X-STREAM-INF:") ||
+ strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
+ strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
+ return AVPROBE_SCORE_MAX;
+ return 0;
+}
+
+AVInputFormat applehttp_demuxer = {
+ "applehttp",
+ NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming format"),
+ sizeof(AppleHTTPContext),
+ applehttp_probe,
+ applehttp_read_header,
+ applehttp_read_packet,
+ applehttp_close,
+ applehttp_read_seek,
+};
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