Rename SafeStringStream -> locked_stringstream. Bump deps for removal of stringstream.

[dcpomatic.git] / src / lib / audio_decoder_stream.cc

diff --git a/src/lib/audio_decoder_stream.cc b/src/lib/audio_decoder_stream.cc
index cd2e3a38811d8fe9794564aa17ed7b72c7c45dbe..150e7c2429f0f329e33ee3819dc6bbbff726fa16 100644 (file)
--- a/src/lib/audio_decoder_stream.cc
+++ b/src/lib/audio_decoder_stream.cc
@@ -1,19 +1,20 @@
 /*
     Copyright (C) 2012-2016 Carl Hetherington <cth@carlh.net>
 
-    This program is free software; you can redistribute it and/or modify
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic 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,
+    DCP-o-matic 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.
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 
@@ -39,14 +40,18 @@ using std::max;
 using boost::optional;
 using boost::shared_ptr;
 
-AudioDecoderStream::AudioDecoderStream (shared_ptr<const AudioContent> content, AudioStreamPtr stream, AudioDecoder* decoder, shared_ptr<Log> log)
+AudioDecoderStream::AudioDecoderStream (shared_ptr<const AudioContent> content, AudioStreamPtr stream, Decoder* decoder, shared_ptr<Log> log)
        : _content (content)
        , _stream (stream)
        , _decoder (decoder)
        , _log (log)
+         /* We effectively start having done a seek to zero; this allows silence-padding of the first
+            data that comes out of our decoder.
+         */
+       , _seek_reference (ContentTime ())
 {
        if (content->resampled_frame_rate() != _stream->frame_rate() && _stream->channels() > 0) {
-               _resampler.reset (new Resampler (_stream->frame_rate(), content->resampled_frame_rate(), _stream->channels (), decoder->fast ()));
+               _resampler.reset (new Resampler (_stream->frame_rate(), content->resampled_frame_rate(), _stream->channels ()));
        }
 
        reset_decoded ();
@@ -67,9 +72,15 @@ AudioDecoderStream::get (Frame frame, Frame length, bool accurate)
 
        Frame const end = frame + length - 1;
 
-       if (frame < _decoded.frame || end > (_decoded.frame + length * 4)) {
-               /* Either we have no decoded data, or what we do have is a long way from what we want: seek */
-               seek (ContentTime::from_frames (frame, _content->resampled_frame_rate()), accurate);
+       /* If we are less than (about) 5 seconds behind the data that we want we'll
+          run through it rather than seeking.
+       */
+       Frame const slack = 5 * 48000;
+
+       if (frame < _decoded.frame || end > (_decoded.frame + _decoded.audio->frames() + slack)) {
+               /* Either we have no decoded data, all our data is after the time that we
+                  want, or what we do have is a long way from what we want: seek */
+               _decoder->seek (ContentTime::from_frames (frame, _content->resampled_frame_rate()), accurate);
        }
 
        /* Offset of the data that we want from the start of _decoded.audio
@@ -161,20 +172,6 @@ AudioDecoderStream::audio (shared_ptr<const AudioBuffers> data, ContentTime time
                        padded->copy_from (data.get(), data->frames(), 0, delta_frames);
                        data = padded;
                        time -= delta;
-               } else if (delta_frames < 0) {
-                       /* This data comes before the seek time.  Throw some data away */
-                       Frame const to_discard = min (-delta_frames, static_cast<Frame> (data->frames()));
-                       Frame const to_keep = data->frames() - to_discard;
-                       if (to_keep == 0) {
-                               /* We have to throw all this data away, so keep _seek_reference and
-                                  try again next time some data arrives.
-                               */
-                               return;
-                       }
-                       shared_ptr<AudioBuffers> trimmed (new AudioBuffers (data->channels(), to_keep));
-                       trimmed->copy_from (data.get(), to_keep, to_discard, 0);
-                       data = trimmed;
-                       time += ContentTime::from_frames (to_discard, frame_rate);
                }
                _seek_reference = optional<ContentTime> ();
        }
@@ -248,3 +245,11 @@ AudioDecoderStream::seek (ContentTime t, bool accurate)
                _seek_reference = t;
        }
 }
+
+void
+AudioDecoderStream::set_fast ()
+{
+       if (_resampler) {
+               _resampler->set_fast ();
+       }
+}