2 Copyright (C) 2012-2021 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/>.
22 #include "compose.hpp"
24 #include "frame_interval_checker.h"
26 #include "j2k_image_proxy.h"
28 #include "raw_image_proxy.h"
29 #include "video_decoder.h"
36 using std::dynamic_pointer_cast;
37 using std::shared_ptr;
38 using namespace dcpomatic;
41 VideoDecoder::VideoDecoder (Decoder* parent, shared_ptr<const Content> c)
42 : DecoderPart (parent)
44 , _frame_interval_checker (new FrameIntervalChecker())
50 /** Called by decoder classes when they have a video frame ready.
51 * @param frame Frame index within the content; this does not take into account 3D
52 * so for 3D_ALTERNATE this value goes:
60 VideoDecoder::emit (shared_ptr<const Film> film, shared_ptr<const ImageProxy> image, Frame decoder_frame)
66 auto const afr = _content->active_video_frame_rate(film);
67 auto const vft = _content->video->frame_type();
69 auto frame_time = ContentTime::from_frames (decoder_frame, afr);
71 /* Do some heuristics to try and spot the case where the user sets content to 3D
72 * when it is not. We try to tell this by looking at the differences in time between
73 * the first few frames. Real 3D content should have two frames for each timestamp.
75 if (_frame_interval_checker) {
76 _frame_interval_checker->feed (frame_time, afr);
77 if (_frame_interval_checker->guess() == FrameIntervalChecker::PROBABLY_NOT_3D && vft == VideoFrameType::THREE_D) {
78 boost::throw_exception (
81 _("The content file %1 is set as 3D but does not appear to contain 3D images. Please set it to 2D. "
82 "You can still make a 3D DCP from this content by ticking the 3D option in the DCP video tab."),
89 if (_frame_interval_checker->guess() != FrameIntervalChecker::AGAIN) {
90 _frame_interval_checker.reset ();
95 Eyes eyes = Eyes::BOTH;
97 /* This is the first data we have received since initialisation or seek. Set
98 the position based on the frame that was given. After this first time
99 we just cound frames, since (as with audio) it seems that ContentTimes
100 are unreliable from FFmpegDecoder. They are much better than audio times
101 but still we get the occasional one which is duplicated. In this case
102 ffmpeg seems to carry on regardless, processing the video frame as normal.
103 If we drop the frame with the duplicated timestamp we obviously lose sync.
106 if (vft == VideoFrameType::THREE_D_ALTERNATE) {
107 frame = decoder_frame / 2;
108 eyes = (decoder_frame % 1) ? Eyes::RIGHT : Eyes::LEFT;
110 frame = decoder_frame;
111 if (vft == VideoFrameType::THREE_D) {
112 auto j2k = dynamic_pointer_cast<const J2KImageProxy>(image);
113 /* At the moment only DCP decoders producers VideoFrameType::THREE_D, so only the J2KImageProxy
114 * knows which eye it is.
116 if (j2k && j2k->eye()) {
117 eyes = j2k->eye().get() == dcp::Eye::LEFT ? Eyes::LEFT : Eyes::RIGHT;
122 _position = ContentTime::from_frames (frame, afr);
124 if (vft == VideoFrameType::THREE_D) {
125 auto j2k = dynamic_pointer_cast<const J2KImageProxy>(image);
126 if (j2k && j2k->eye()) {
127 if (j2k->eye() == dcp::Eye::LEFT) {
128 frame = _position->frames_round(afr) + 1;
131 frame = _position->frames_round(afr);
135 /* This should not happen; see above */
136 frame = _position->frames_round(afr) + 1;
138 } else if (vft == VideoFrameType::THREE_D_ALTERNATE) {
139 DCPOMATIC_ASSERT (_last_emitted_eyes);
140 if (_last_emitted_eyes.get() == Eyes::RIGHT) {
141 frame = _position->frames_round(afr) + 1;
144 frame = _position->frames_round(afr);
148 frame = _position->frames_round(afr) + 1;
153 case VideoFrameType::TWO_D:
154 case VideoFrameType::THREE_D:
155 Data (ContentVideo (image, frame, eyes, Part::WHOLE));
157 case VideoFrameType::THREE_D_ALTERNATE:
159 Data (ContentVideo (image, frame, eyes, Part::WHOLE));
160 _last_emitted_eyes = eyes;
163 case VideoFrameType::THREE_D_LEFT_RIGHT:
164 Data (ContentVideo (image, frame, Eyes::LEFT, Part::LEFT_HALF));
165 Data (ContentVideo (image, frame, Eyes::RIGHT, Part::RIGHT_HALF));
167 case VideoFrameType::THREE_D_TOP_BOTTOM:
168 Data (ContentVideo (image, frame, Eyes::LEFT, Part::TOP_HALF));
169 Data (ContentVideo (image, frame, Eyes::RIGHT, Part::BOTTOM_HALF));
171 case VideoFrameType::THREE_D_LEFT:
172 Data (ContentVideo (image, frame, Eyes::LEFT, Part::WHOLE));
174 case VideoFrameType::THREE_D_RIGHT:
175 Data (ContentVideo (image, frame, Eyes::RIGHT, Part::WHOLE));
178 DCPOMATIC_ASSERT (false);
181 _position = ContentTime::from_frames (frame, afr);
186 VideoDecoder::seek ()
188 _position = boost::none;
189 _last_emitted_eyes.reset ();
190 _frame_interval_checker.reset (new FrameIntervalChecker());