Support encoding of MPEG2 DCPs.

1 files changed, 80 insertions, 0 deletions

diff --git a/src/lib/mpeg2_encoder.cc b/src/lib/mpeg2_encoder.cc
new file mode 100644
index 000000000..49bff19d4
--- /dev/null
+++ b/src/lib/mpeg2_encoder.cc
@@ -0,0 +1,80 @@
+/*
+    Copyright (C) 2024 Carl Hetherington <cth@carlh.net>
+
+    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.
+
+    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 DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "mpeg2_encoder.h"
+#include "writer.h"
+#include <dcp/ffmpeg_image.h>
+extern "C" {
+#include <libavutil/pixfmt.h>
+}
+
+
+using std::shared_ptr;
+
+
+MPEG2Encoder::MPEG2Encoder(shared_ptr<const Film> film, Writer& writer)
+	: VideoEncoder(film, writer)
+	, _transcoder(film->frame_size(), film->video_frame_rate(), film->video_bit_rate())
+{
+
+}
+
+
+void
+MPEG2Encoder::encode(shared_ptr<PlayerVideo> pv, dcpomatic::DCPTime time)
+{
+	VideoEncoder::encode(pv, time);
+
+	auto image = pv->image(
+		[](AVPixelFormat) { return AV_PIX_FMT_YUV420P; },
+		VideoRange::VIDEO,
+		false
+		);
+
+	dcp::FFmpegImage ffmpeg_image(time.get() * _film->video_frame_rate() / dcpomatic::DCPTime::HZ);
+
+	DCPOMATIC_ASSERT(image->size() == ffmpeg_image.size());
+
+	auto height = image->size().height;
+
+	for (int y = 0; y < height; ++y) {
+		memcpy(ffmpeg_image.y() + ffmpeg_image.y_stride() * y, image->data()[0] + image->stride()[0] * y, ffmpeg_image.y_stride());
+	}
+
+	for (int y = 0; y < height / 2; ++y) {
+		memcpy(ffmpeg_image.u() + ffmpeg_image.u_stride() * y, image->data()[1] + image->stride()[1] * y, ffmpeg_image.u_stride());
+		memcpy(ffmpeg_image.v() + ffmpeg_image.v_stride() * y, image->data()[2] + image->stride()[2] * y, ffmpeg_image.v_stride());
+	}
+
+	if (auto compressed = _transcoder.compress_frame(std::move(ffmpeg_image))) {
+		_writer.write(compressed->first, compressed->second);
+	}
+}
+
+
+void
+MPEG2Encoder::end()
+{
+	if (auto compressed = _transcoder.flush()) {
+		_writer.write(compressed->first, compressed->second);
+	}
+}
+