| /* |
| * Copyright (c) 2015, Vignesh Venkatasubramanian |
| * |
| * 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 WebM Chunk Muxer |
| * The chunk muxer enables writing WebM Live chunks where there is a header |
| * chunk, followed by data chunks where each Cluster is written out as a Chunk. |
| */ |
| |
| #include "avformat.h" |
| #include "avio.h" |
| #include "avio_internal.h" |
| #include "internal.h" |
| |
| #include "libavutil/log.h" |
| #include "libavutil/opt.h" |
| #include "libavutil/mathematics.h" |
| |
| #define MAX_FILENAME_SIZE 1024 |
| |
| typedef struct WebMChunkContext { |
| const AVClass *class; |
| char *header_filename; |
| int chunk_duration; |
| int chunk_index; |
| char *http_method; |
| uint64_t duration_written; |
| int64_t prev_pts; |
| AVFormatContext *avf; |
| int header_written; |
| } WebMChunkContext; |
| |
| static int webm_chunk_init(AVFormatContext *s) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| ff_const59 AVOutputFormat *oformat; |
| AVFormatContext *oc; |
| AVStream *st, *ost = s->streams[0]; |
| AVDictionary *dict = NULL; |
| int ret; |
| |
| // DASH Streams can only have one track per file. |
| if (s->nb_streams != 1) |
| return AVERROR(EINVAL); |
| |
| if (!wc->header_filename) { |
| av_log(s, AV_LOG_ERROR, "No header filename provided\n"); |
| return AVERROR(EINVAL); |
| } |
| |
| wc->prev_pts = AV_NOPTS_VALUE; |
| |
| oformat = av_guess_format("webm", s->url, "video/webm"); |
| if (!oformat) |
| return AVERROR_MUXER_NOT_FOUND; |
| |
| ret = avformat_alloc_output_context2(&wc->avf, oformat, NULL, NULL); |
| if (ret < 0) |
| return ret; |
| oc = wc->avf; |
| |
| ff_format_set_url(oc, wc->header_filename); |
| wc->header_filename = NULL; |
| |
| oc->interrupt_callback = s->interrupt_callback; |
| oc->max_delay = s->max_delay; |
| oc->flags = s->flags & ~AVFMT_FLAG_FLUSH_PACKETS; |
| oc->strict_std_compliance = s->strict_std_compliance; |
| oc->avoid_negative_ts = s->avoid_negative_ts; |
| |
| oc->flush_packets = 0; |
| |
| if ((ret = av_dict_copy(&oc->metadata, s->metadata, 0)) < 0) |
| return ret; |
| |
| if (!(st = avformat_new_stream(oc, NULL))) |
| return AVERROR(ENOMEM); |
| |
| if ((ret = avcodec_parameters_copy(st->codecpar, ost->codecpar)) < 0 || |
| (ret = av_dict_copy(&st->metadata, ost->metadata, 0)) < 0) |
| return ret; |
| |
| st->sample_aspect_ratio = ost->sample_aspect_ratio; |
| st->disposition = ost->disposition; |
| avpriv_set_pts_info(st, ost->pts_wrap_bits, ost->time_base.num, |
| ost->time_base.den); |
| |
| if (wc->http_method) |
| if ((ret = av_dict_set(&dict, "method", wc->http_method, 0)) < 0) |
| return ret; |
| ret = s->io_open(s, &oc->pb, oc->url, AVIO_FLAG_WRITE, &dict); |
| av_dict_free(&dict); |
| if (ret < 0) |
| return ret; |
| oc->pb->seekable = 0; |
| |
| if ((ret = av_dict_set_int(&dict, "dash", 1, 0)) < 0 || |
| (ret = av_dict_set_int(&dict, "cluster_time_limit", |
| wc->chunk_duration, 0)) < 0 || |
| (ret = av_dict_set_int(&dict, "live", 1, 0)) < 0) |
| goto fail; |
| |
| ret = avformat_init_output(oc, &dict); |
| fail: |
| av_dict_free(&dict); |
| if (ret < 0) |
| return ret; |
| |
| // Copy the timing info back to the original stream |
| // so that the timestamps of the packets are directly usable |
| avpriv_set_pts_info(ost, st->pts_wrap_bits, st->time_base.num, |
| st->time_base.den); |
| |
| // This ensures that the timestamps will already be properly shifted |
| // when the packets arrive here, so we don't need to shift again. |
| s->avoid_negative_ts = oc->avoid_negative_ts; |
| s->internal->avoid_negative_ts_use_pts = |
| oc->internal->avoid_negative_ts_use_pts; |
| oc->avoid_negative_ts = 0; |
| |
| return 0; |
| } |
| |
| static int get_chunk_filename(AVFormatContext *s, char filename[MAX_FILENAME_SIZE]) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| if (!filename) { |
| return AVERROR(EINVAL); |
| } |
| if (av_get_frame_filename(filename, MAX_FILENAME_SIZE, |
| s->url, wc->chunk_index - 1) < 0) { |
| av_log(s, AV_LOG_ERROR, "Invalid chunk filename template '%s'\n", s->url); |
| return AVERROR(EINVAL); |
| } |
| return 0; |
| } |
| |
| static int webm_chunk_write_header(AVFormatContext *s) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| AVFormatContext *oc = wc->avf; |
| int ret; |
| |
| ret = avformat_write_header(oc, NULL); |
| ff_format_io_close(s, &oc->pb); |
| wc->header_written = 1; |
| if (ret < 0) |
| return ret; |
| return 0; |
| } |
| |
| static int chunk_start(AVFormatContext *s) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| AVFormatContext *oc = wc->avf; |
| int ret; |
| |
| ret = avio_open_dyn_buf(&oc->pb); |
| if (ret < 0) |
| return ret; |
| wc->chunk_index++; |
| return 0; |
| } |
| |
| static int chunk_end(AVFormatContext *s, int flush) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| AVFormatContext *oc = wc->avf; |
| int ret; |
| int buffer_size; |
| uint8_t *buffer; |
| AVIOContext *pb; |
| char filename[MAX_FILENAME_SIZE]; |
| AVDictionary *options = NULL; |
| |
| if (!oc->pb) |
| return 0; |
| |
| if (flush) |
| // Flush the cluster in WebM muxer. |
| av_write_frame(oc, NULL); |
| buffer_size = avio_close_dyn_buf(oc->pb, &buffer); |
| oc->pb = NULL; |
| ret = get_chunk_filename(s, filename); |
| if (ret < 0) |
| goto fail; |
| if (wc->http_method) |
| if ((ret = av_dict_set(&options, "method", wc->http_method, 0)) < 0) |
| goto fail; |
| ret = s->io_open(s, &pb, filename, AVIO_FLAG_WRITE, &options); |
| av_dict_free(&options); |
| if (ret < 0) |
| goto fail; |
| avio_write(pb, buffer, buffer_size); |
| ff_format_io_close(s, &pb); |
| fail: |
| av_free(buffer); |
| return (ret < 0) ? ret : 0; |
| } |
| |
| static int webm_chunk_write_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| AVFormatContext *oc = wc->avf; |
| AVStream *st = s->streams[pkt->stream_index]; |
| int ret; |
| |
| if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) { |
| if (wc->prev_pts != AV_NOPTS_VALUE) |
| wc->duration_written += av_rescale_q(pkt->pts - wc->prev_pts, |
| st->time_base, |
| (AVRational) {1, 1000}); |
| wc->prev_pts = pkt->pts; |
| } |
| |
| // For video, a new chunk is started only on key frames. For audio, a new |
| // chunk is started based on chunk_duration. Also, a new chunk is started |
| // unconditionally if there is no currently open chunk. |
| if (!oc->pb || (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && |
| (pkt->flags & AV_PKT_FLAG_KEY)) || |
| (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && |
| wc->duration_written >= wc->chunk_duration)) { |
| wc->duration_written = 0; |
| if ((ret = chunk_end(s, 1)) < 0 || (ret = chunk_start(s)) < 0) { |
| return ret; |
| } |
| } |
| |
| // We only have one stream, so use the non-interleaving av_write_frame. |
| return av_write_frame(oc, pkt); |
| } |
| |
| static int webm_chunk_write_trailer(AVFormatContext *s) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| AVFormatContext *oc = wc->avf; |
| int ret; |
| |
| if (!oc->pb) { |
| ret = chunk_start(s); |
| if (ret < 0) |
| return ret; |
| } |
| ret = av_write_trailer(oc); |
| if (ret < 0) |
| return ret; |
| return chunk_end(s, 0); |
| } |
| |
| static void webm_chunk_deinit(AVFormatContext *s) |
| { |
| WebMChunkContext *wc = s->priv_data; |
| |
| if (!wc->avf) |
| return; |
| |
| if (wc->header_written) |
| ffio_free_dyn_buf(&wc->avf->pb); |
| else |
| ff_format_io_close(s, &wc->avf->pb); |
| avformat_free_context(wc->avf); |
| wc->avf = NULL; |
| } |
| |
| #define OFFSET(x) offsetof(WebMChunkContext, x) |
| static const AVOption options[] = { |
| { "chunk_start_index", "start index of the chunk", OFFSET(chunk_index), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM }, |
| { "header", "filename of the header where the initialization data will be written", OFFSET(header_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM }, |
| { "audio_chunk_duration", "duration of each chunk in milliseconds", OFFSET(chunk_duration), AV_OPT_TYPE_INT, {.i64 = 5000}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM }, |
| { "method", "set the HTTP method", OFFSET(http_method), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM }, |
| { NULL }, |
| }; |
| |
| static const AVClass webm_chunk_class = { |
| .class_name = "WebM Chunk Muxer", |
| .item_name = av_default_item_name, |
| .option = options, |
| .version = LIBAVUTIL_VERSION_INT, |
| }; |
| |
| AVOutputFormat ff_webm_chunk_muxer = { |
| .name = "webm_chunk", |
| .long_name = NULL_IF_CONFIG_SMALL("WebM Chunk Muxer"), |
| .mime_type = "video/webm", |
| .extensions = "chk", |
| .flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER | AVFMT_NEEDNUMBER | |
| AVFMT_TS_NONSTRICT, |
| .priv_data_size = sizeof(WebMChunkContext), |
| .init = webm_chunk_init, |
| .write_header = webm_chunk_write_header, |
| .write_packet = webm_chunk_write_packet, |
| .write_trailer = webm_chunk_write_trailer, |
| .deinit = webm_chunk_deinit, |
| .priv_class = &webm_chunk_class, |
| }; |