2 Copyright (C) 2012-2020 Carl Hetherington <cth@carlh.net>
4 This file is part of DCP-o-matic.
6 DCP-o-matic is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 DCP-o-matic is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
21 #include "video_decoder.h"
23 #include "raw_image_proxy.h"
26 #include "frame_interval_checker.h"
27 #include "compose.hpp"
28 #include <boost/foreach.hpp>
36 using std::back_inserter;
37 using boost::shared_ptr;
38 using boost::optional;
39 using namespace dcpomatic;
41 VideoDecoder::VideoDecoder (Decoder* parent, shared_ptr<const Content> c)
42 : DecoderPart (parent)
44 , _frame_interval_checker (new FrameIntervalChecker())
49 /** Called by decoder classes when they have a video frame ready.
50 * @param frame Frame index within the content; this does not take into account 3D
51 * so for 3D_ALTERNATE this value goes:
59 VideoDecoder::emit (shared_ptr<const Film> film, shared_ptr<const ImageProxy> image, Frame decoder_frame)
65 double const afr = _content->active_video_frame_rate(film);
66 VideoFrameType const vft = _content->video->frame_type();
68 ContentTime frame_time = ContentTime::from_frames (decoder_frame, afr);
70 /* Do some heuristics to try and spot the case where the user sets content to 3D
71 * when it is not. We try to tell this by looking at the differences in time between
72 * the first few frames. Real 3D content should have two frames for each timestamp.
74 if (_frame_interval_checker) {
75 _frame_interval_checker->feed (frame_time, afr);
76 if (_frame_interval_checker->guess() == FrameIntervalChecker::PROBABLY_NOT_3D && vft == VIDEO_FRAME_TYPE_3D) {
77 boost::throw_exception (
80 _("The content file %1 is set as 3D but does not appear to contain 3D images. Please set it to 2D. "
81 "You can still make a 3D DCP from this content by ticking the 3D option in the DCP video tab."),
88 if (_frame_interval_checker->guess() != FrameIntervalChecker::AGAIN) {
89 _frame_interval_checker.reset ();
94 Eyes eyes = EYES_BOTH;
96 /* This is the first data we have received since initialisation or seek. Set
97 the position based on the frame that was given. After this first time
98 we just cound frames, since (as with audio) it seems that ContentTimes
99 are unreliable from FFmpegDecoder. They are much better than audio times
100 but still we get the occasional one which is duplicated. In this case
101 ffmpeg seems to carry on regardless, processing the video frame as normal.
102 If we drop the frame with the duplicated timestamp we obviously lose sync.
104 _position = ContentTime::from_frames (decoder_frame, afr);
105 if (vft == VIDEO_FRAME_TYPE_3D_ALTERNATE) {
106 frame = decoder_frame / 2;
107 _last_emitted_eyes = EYES_RIGHT;
109 frame = decoder_frame;
112 if (vft == VIDEO_FRAME_TYPE_3D || vft == VIDEO_FRAME_TYPE_3D_ALTERNATE) {
113 DCPOMATIC_ASSERT (_last_emitted_eyes);
114 if (_last_emitted_eyes.get() == EYES_RIGHT) {
115 frame = _position->frames_round(afr) + 1;
118 frame = _position->frames_round(afr);
122 frame = _position->frames_round(afr) + 1;
127 case VIDEO_FRAME_TYPE_2D:
128 Data (ContentVideo (image, frame, EYES_BOTH, PART_WHOLE));
130 case VIDEO_FRAME_TYPE_3D:
132 Data (ContentVideo (image, frame, eyes, PART_WHOLE));
133 _last_emitted_frame = frame;
134 _last_emitted_eyes = eyes;
137 case VIDEO_FRAME_TYPE_3D_ALTERNATE:
139 Data (ContentVideo (image, frame, eyes, PART_WHOLE));
140 _last_emitted_eyes = eyes;
143 case VIDEO_FRAME_TYPE_3D_LEFT_RIGHT:
144 Data (ContentVideo (image, frame, EYES_LEFT, PART_LEFT_HALF));
145 Data (ContentVideo (image, frame, EYES_RIGHT, PART_RIGHT_HALF));
147 case VIDEO_FRAME_TYPE_3D_TOP_BOTTOM:
148 Data (ContentVideo (image, frame, EYES_LEFT, PART_TOP_HALF));
149 Data (ContentVideo (image, frame, EYES_RIGHT, PART_BOTTOM_HALF));
151 case VIDEO_FRAME_TYPE_3D_LEFT:
152 Data (ContentVideo (image, frame, EYES_LEFT, PART_WHOLE));
154 case VIDEO_FRAME_TYPE_3D_RIGHT:
155 Data (ContentVideo (image, frame, EYES_RIGHT, PART_WHOLE));
158 DCPOMATIC_ASSERT (false);
161 _position = ContentTime::from_frames (frame, afr);
165 VideoDecoder::seek ()
167 _position = boost::none;
168 _last_emitted_frame.reset ();
169 _last_emitted_eyes.reset ();
170 _frame_interval_checker.reset (new FrameIntervalChecker());