2 Copyright (C) 2013 Carl Hetherington <cth@carlh.net>
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #include <libavcodec/avcodec.h>
22 #include <libavformat/avformat.h>
23 #include <libswscale/swscale.h>
26 #include "ffmpeg_content.h"
27 #include "exceptions.h"
34 using std::stringstream;
35 using boost::shared_ptr;
36 using boost::lexical_cast;
38 /* This should not really be a pointer, but I find that __cxa_finalize tries
39 * to destroy the mutex while a call to ~FFmpeg is in progress; this crashes
40 * with a failure of assert (!posix::pthread_mutex_destroy(&m));
42 * The hacky work-around is never to destroy the mutex...
44 boost::mutex* FFmpeg::_mutex;
46 FFmpeg::FFmpeg (boost::shared_ptr<const FFmpegContent> c)
49 , _avio_buffer_size (4096)
56 _mutex = new boost::mutex ();
66 boost::mutex::scoped_lock lm (*_mutex);
68 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
69 AVCodecContext* context = _format_context->streams[i]->codec;
70 if (context->codec_type == AVMEDIA_TYPE_VIDEO || context->codec_type == AVMEDIA_TYPE_AUDIO) {
71 avcodec_close (context);
75 av_frame_free (&_frame);
77 avformat_close_input (&_format_context);
81 avio_read_wrapper (void* data, uint8_t* buffer, int amount)
83 return reinterpret_cast<FFmpeg*>(data)->avio_read (buffer, amount);
87 avio_seek_wrapper (void* data, int64_t offset, int whence)
89 return reinterpret_cast<FFmpeg*>(data)->avio_seek (offset, whence);
93 FFmpeg::setup_general ()
97 _file_group.set_paths (_ffmpeg_content->paths ());
98 _avio_buffer = static_cast<uint8_t*> (wrapped_av_malloc (_avio_buffer_size));
99 _avio_context = avio_alloc_context (_avio_buffer, _avio_buffer_size, 0, this, avio_read_wrapper, 0, avio_seek_wrapper);
100 _format_context = avformat_alloc_context ();
101 _format_context->pb = _avio_context;
103 AVDictionary* options = 0;
104 /* These durations are in microseconds, and represent how far into the content file
105 we will look for streams.
107 av_dict_set (&options, "analyzeduration", lexical_cast<string> (5 * 60 * 1e6).c_str(), 0);
108 av_dict_set (&options, "probesize", lexical_cast<string> (5 * 60 * 1e6).c_str(), 0);
110 if (avformat_open_input (&_format_context, 0, 0, &options) < 0) {
111 throw OpenFileError (_ffmpeg_content->path(0).string ());
114 if (avformat_find_stream_info (_format_context, 0) < 0) {
115 throw DecodeError (_("could not find stream information"));
118 /* Find video stream */
120 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
121 AVStream* s = _format_context->streams[i];
122 if (s->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
127 if (_video_stream < 0) {
128 throw DecodeError (N_("could not find video stream"));
131 /* Hack: if the AVStreams have zero IDs, put some in. We
132 use the IDs so that we can cope with VOBs, in which streams
133 move about in index but remain with the same ID in different
134 VOBs. However, some files have all-zero IDs, hence this hack.
138 while (i < _format_context->nb_streams && _format_context->streams[i]->id == 0) {
142 if (i == _format_context->nb_streams) {
143 /* Put in our own IDs */
144 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
145 _format_context->streams[i]->id = i;
149 _frame = av_frame_alloc ();
151 throw DecodeError (N_("could not allocate frame"));
156 FFmpeg::setup_video ()
158 boost::mutex::scoped_lock lm (*_mutex);
160 assert (_video_stream >= 0);
161 AVCodecContext* context = _format_context->streams[_video_stream]->codec;
162 AVCodec* codec = avcodec_find_decoder (context->codec_id);
165 throw DecodeError (_("could not find video decoder"));
168 if (avcodec_open2 (context, codec, 0) < 0) {
169 throw DecodeError (N_("could not open video decoder"));
174 FFmpeg::setup_audio ()
176 boost::mutex::scoped_lock lm (*_mutex);
178 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
179 AVCodecContext* context = _format_context->streams[i]->codec;
180 if (context->codec_type != AVMEDIA_TYPE_AUDIO) {
184 AVCodec* codec = avcodec_find_decoder (context->codec_id);
186 throw DecodeError (_("could not find audio decoder"));
189 if (avcodec_open2 (context, codec, 0) < 0) {
190 throw DecodeError (N_("could not open audio decoder"));
197 FFmpeg::video_codec_context () const
199 return _format_context->streams[_video_stream]->codec;
203 FFmpeg::audio_codec_context () const
205 if (!_ffmpeg_content->audio_stream ()) {
209 return _ffmpeg_content->audio_stream()->stream(_format_context)->codec;
213 FFmpeg::avio_read (uint8_t* buffer, int const amount)
215 return _file_group.read (buffer, amount);
219 FFmpeg::avio_seek (int64_t const pos, int whence)
221 if (whence == AVSEEK_SIZE) {
222 return _file_group.length ();
225 return _file_group.seek (pos, whence);