2 Copyright (C) 2012 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.
29 using boost::shared_ptr;
31 Matcher::Matcher (Log* log, int sample_rate, float frames_per_second)
33 , _sample_rate (sample_rate)
34 , _frames_per_second (frames_per_second)
42 Matcher::process_video (boost::shared_ptr<Image> image, bool same, boost::shared_ptr<Subtitle> sub, double t)
44 _pixel_format = image->pixel_format ();
45 _size = image->size ();
47 _log->log(String::compose("Matcher video @ %1 (same=%2)", t, same));
53 if (_audio_frames == 0 && _pending_audio.empty ()) {
54 /* No audio yet; we must postpone this frame until we have some */
55 _pending_video.push_back (VideoRecord (image, same, sub, t));
56 } else if (!_pending_audio.empty() && _pending_video.empty ()) {
57 /* First video since we got audio */
58 _pending_video.push_back (VideoRecord (image, same, sub, t));
63 /* Difference between where this video is and where it should be */
64 double const delta = t - _first_input.get() - _video_frames / _frames_per_second;
65 double const one_frame = 1 / _frames_per_second;
67 if (delta > one_frame) {
68 /* Insert frames to make up the difference */
69 int const extra = rint (delta / one_frame);
70 for (int i = 0; i < extra; ++i) {
72 _log->log (String::compose ("Extra video frame inserted at %1s", _video_frames / _frames_per_second));
76 if (delta > -one_frame) {
77 Video (image, same, sub);
80 /* We are omitting a frame to keep things right */
81 _log->log (String::compose ("Frame removed at %1s", t));
90 Matcher::process_audio (boost::shared_ptr<AudioBuffers> b, double t)
92 _channels = b->channels ();
98 if (_video_frames == 0 && _pending_video.empty ()) {
99 /* No video yet; we must postpone these data until we have some */
100 _pending_audio.push_back (AudioRecord (b, t));
101 } else if (!_pending_video.empty() && _pending_audio.empty ()) {
102 /* First audio since we got video */
103 _pending_audio.push_back (AudioRecord (b, t));
106 /* Normal running. We assume audio time stamps are consecutive */
108 _audio_frames += b->frames ();
113 Matcher::process_end ()
115 if (_audio_frames == 0 || !_pixel_format || !_size || !_channels) {
116 /* We won't do anything */
120 _log->log (String::compose ("Matcher has seen %1 video frames (which equals %2 audio frames) and %3 audio frames",
121 _video_frames, video_frames_to_audio_frames (_video_frames, _sample_rate, _frames_per_second), _audio_frames));
123 match ((double (_audio_frames) / _sample_rate) - (double (_video_frames) / _frames_per_second));
127 Matcher::fix_start ()
129 assert (!_pending_video.empty ());
130 assert (!_pending_audio.empty ());
132 _log->log (String::compose ("Fixing start; video at %1, audio at %2", _pending_video.front().time, _pending_audio.front().time));
134 match (_pending_video.front().time - _pending_audio.front().time);
136 for (list<VideoRecord>::iterator i = _pending_video.begin(); i != _pending_video.end(); ++i) {
137 process_video (i->image, i->same, i->subtitle, i->time);
140 for (list<AudioRecord>::iterator i = _pending_audio.begin(); i != _pending_audio.end(); ++i) {
141 process_audio (i->audio, i->time);
144 _pending_video.clear ();
145 _pending_audio.clear ();
149 Matcher::match (double extra_video_needed)
151 if (extra_video_needed > 0) {
153 /* Emit black video frames */
155 int const black_video_frames = ceil (extra_video_needed * _frames_per_second);
157 _log->log (String::compose (N_("Emitting %1 frames of black video"), black_video_frames));
159 shared_ptr<Image> black (new SimpleImage (_pixel_format.get(), _size.get(), true));
160 black->make_black ();
161 for (int i = 0; i < black_video_frames; ++i) {
162 Video (black, i != 0, shared_ptr<Subtitle>());
166 extra_video_needed -= black_video_frames / _frames_per_second;
169 if (extra_video_needed < 0) {
173 int64_t to_do = -extra_video_needed * _sample_rate;
174 _log->log (String::compose (N_("Emitted %1 frames of silence"), to_do));
176 /* Do things in half second blocks as I think there may be limits
177 to what FFmpeg (and in particular the resampler) can cope with.
179 int64_t const block = _sample_rate / 2;
180 shared_ptr<AudioBuffers> b (new AudioBuffers (_channels.get(), block));
184 int64_t const this_time = min (to_do, block);
185 b->set_frames (this_time);
187 _audio_frames += b->frames ();
194 Matcher::repeat_last_video ()
197 _last_image.reset (new SimpleImage (_pixel_format.get(), _size.get(), true));
198 _last_image->make_black ();
201 Video (_last_image, true, _last_subtitle);