Support MPEG2 decompression.

1 files changed, 83 insertions, 0 deletions

diff --git a/src/mono_mpeg2_picture_frame.cc b/src/mono_mpeg2_picture_frame.cc
new file mode 100644
index 00000000..3da67212
--- /dev/null
+++ b/src/mono_mpeg2_picture_frame.cc
@@ -0,0 +1,83 @@
+/*
+    Copyright (C) 2023 Carl Hetherington <cth@carlh.net>
+
+    This file is part of libdcp.
+
+    libdcp 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.
+
+    libdcp 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 libdcp.  If not, see <http://www.gnu.org/licenses/>.
+
+    In addition, as a special exception, the copyright holders give
+    permission to link the code of portions of this program with the
+    OpenSSL library under certain conditions as described in each
+    individual source file, and distribute linked combinations
+    including the two.
+
+    You must obey the GNU General Public License in all respects
+    for all of the code used other than OpenSSL.  If you modify
+    file(s) with this exception, you may extend this exception to your
+    version of the file(s), but you are not obligated to do so.  If you
+    do not wish to do so, delete this exception statement from your
+    version.  If you delete this exception statement from all source
+    files in the program, then also delete it here.
+*/
+
+
+#include "compose.hpp"
+#include "mono_mpeg2_picture_frame.h"
+
+
+using std::make_shared;
+using std::shared_ptr;
+using namespace dcp;
+
+
+
+/** Make a picture frame from a 2D (monoscopic) asset.
+ *  @param reader Reader for the asset's MXF file.
+ *  @param n Frame within the asset, not taking EntryPoint into account.
+ *  @param c Context for decryption, or 0.
+ *  @param check_hmac true to check the HMAC and give an error if it is not as expected.
+ */
+MonoMPEG2PictureFrame::MonoMPEG2PictureFrame(ASDCP::MPEG2::MXFReader* reader, int n, shared_ptr<DecryptionContext> context, bool check_hmac)
+{
+	/* XXX: unfortunate guesswork on this buffer size */
+	_buffer = make_shared<ASDCP::MPEG2::FrameBuffer>(4 * Kumu::Megabyte);
+
+	auto const r = reader->ReadFrame(n, *_buffer, context->context(), check_hmac ? context->hmac() : nullptr);
+
+	if (ASDCP_FAILURE(r)) {
+		boost::throw_exception(ReadError(String::compose("could not read video frame %1 (%2)", n, static_cast<int>(r))));
+	}
+}
+
+
+uint8_t const *
+MonoMPEG2PictureFrame::data() const
+{
+	return _buffer->RoData();
+}
+
+
+uint8_t *
+MonoMPEG2PictureFrame::data()
+{
+	return _buffer->Data();
+}
+
+
+int
+MonoMPEG2PictureFrame::size() const
+{
+	return _buffer->Size();
+}
+