+/*
+ Copyright (C) 2012 Carl Hetherington <cth@carlh.net>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "audio_analysis.h"
+#include "analyse_audio_job.h"
+#include "compose.hpp"
+#include "film.h"
+#include "options.h"
+#include "decoder_factory.h"
+#include "audio_decoder.h"
+
+using std::string;
+using std::max;
+using boost::shared_ptr;
+
+int const AnalyseAudioJob::_num_points = 1024;
+
+AnalyseAudioJob::AnalyseAudioJob (shared_ptr<Film> f)
+ : Job (f)
+ , _done_for_this_point (0)
+ , _done (0)
+ , _samples_per_point (1)
+{
+
+}
+
+string
+AnalyseAudioJob::name () const
+{
+ return String::compose ("Analyse audio of %1", _film->name());
+}
+
+void
+AnalyseAudioJob::run ()
+{
+ if (!_film->audio_stream () || !_film->length()) {
+ set_progress (1);
+ set_state (FINISHED_ERROR);
+ return;
+ }
+
+ DecodeOptions options;
+ options.decode_video = false;
+
+ Decoders decoders = decoder_factory (_film, options);
+ assert (decoders.audio);
+
+ decoders.audio->set_audio_stream (_film->audio_stream ());
+ decoders.audio->Audio.connect (bind (&AnalyseAudioJob::audio, this, _1));
+
+ int64_t total_audio_frames = video_frames_to_audio_frames (_film->length().get(), _film->audio_stream()->sample_rate(), _film->frames_per_second());
+ _samples_per_point = total_audio_frames / _num_points;
+
+ _current.resize (_film->audio_stream()->channels ());
+ _analysis.reset (new AudioAnalysis (_film->audio_stream()->channels()));
+
+ while (!decoders.audio->pass()) {
+ set_progress (float (_done) / total_audio_frames);
+ }
+
+ _analysis->write (_film->audio_analysis_path ());
+
+ set_progress (1);
+ set_state (FINISHED_OK);
+}
+
+void
+AnalyseAudioJob::audio (shared_ptr<AudioBuffers> b)
+{
+ for (int i = 0; i < b->frames(); ++i) {
+ for (int j = 0; j < b->channels(); ++j) {
+ float const s = b->data(j)[i];
+ _current[j][AudioPoint::RMS] += pow (s, 2);
+ _current[j][AudioPoint::PEAK] = max (_current[j][AudioPoint::PEAK], fabsf (s));
+
+ if (_done_for_this_point == _samples_per_point) {
+ _current[j][AudioPoint::RMS] = 20 * log10 (sqrt (_current[j][AudioPoint::RMS] / _samples_per_point));
+ _current[j][AudioPoint::PEAK] = 20 * log10 (_current[j][AudioPoint::PEAK]);
+
+ _analysis->add_point (j, _current[j]);
+
+ _done_for_this_point = 0;
+ _current[j] = AudioPoint ();
+ }
+ }
+
+ ++_done_for_this_point;
+ }
+
+ _done += b->frames ();
+}
+