Pass around JPEG2000 data as a shared_ptr and hence avoid a copy

of 4MB of data for every JPEG2000 frame we decode.

1 files changed, 19 insertions, 28 deletions

diff --git a/src/lib/j2k_image_proxy.cc b/src/lib/j2k_image_proxy.cc
index 08ebc343c..064bbec7b 100644
--- a/src/lib/j2k_image_proxy.cc
+++ b/src/lib/j2k_image_proxy.cc
@@ -46,12 +46,12 @@ using std::make_pair;
 using boost::shared_ptr;
 using boost::optional;
 using boost::dynamic_pointer_cast;
-using dcp::Data;
+using dcp::ArrayData;
 using dcp::raw_convert;
 
 /** Construct a J2KImageProxy from a JPEG2000 file */
 J2KImageProxy::J2KImageProxy (boost::filesystem::path path, dcp::Size size, AVPixelFormat pixel_format)
-	: _data (path)
+	: _data (new dcp::ArrayData(path))
 	, _size (size)
 	, _pixel_format (pixel_format)
 	, _error (false)
@@ -60,13 +60,14 @@ J2KImageProxy::J2KImageProxy (boost::filesystem::path path, dcp::Size size, AVPi
 	DCPOMATIC_ASSERT (_pixel_format == AV_PIX_FMT_RGB48 || _pixel_format == AV_PIX_FMT_XYZ12LE);
 }
 
+
 J2KImageProxy::J2KImageProxy (
 	shared_ptr<const dcp::MonoPictureFrame> frame,
 	dcp::Size size,
 	AVPixelFormat pixel_format,
 	optional<int> forced_reduction
 	)
-	: _data (frame->j2k_size ())
+	: _data (frame)
 	, _size (size)
 	, _pixel_format (pixel_format)
 	, _forced_reduction (forced_reduction)
@@ -74,9 +75,9 @@ J2KImageProxy::J2KImageProxy (
 {
 	/* ::image assumes 16bpp */
 	DCPOMATIC_ASSERT (_pixel_format == AV_PIX_FMT_RGB48 || _pixel_format == AV_PIX_FMT_XYZ12LE);
-	memcpy (_data.data().get(), frame->j2k_data(), _data.size ());
 }
 
+
 J2KImageProxy::J2KImageProxy (
 	shared_ptr<const dcp::StereoPictureFrame> frame,
 	dcp::Size size,
@@ -84,7 +85,8 @@ J2KImageProxy::J2KImageProxy (
 	AVPixelFormat pixel_format,
 	optional<int> forced_reduction
 	)
-	: _size (size)
+	: _data (eye ? frame->left() : frame->right())
+	, _size (size)
 	, _eye (eye)
 	, _pixel_format (pixel_format)
 	, _forced_reduction (forced_reduction)
@@ -92,18 +94,9 @@ J2KImageProxy::J2KImageProxy (
 {
 	/* ::image assumes 16bpp */
 	DCPOMATIC_ASSERT (_pixel_format == AV_PIX_FMT_RGB48 || _pixel_format == AV_PIX_FMT_XYZ12LE);
-	switch (eye) {
-	case dcp::EYE_LEFT:
-		_data = Data (frame->left_j2k_size ());
-		memcpy (_data.data().get(), frame->left_j2k_data(), _data.size ());
-		break;
-	case dcp::EYE_RIGHT:
-		_data = Data (frame->right_j2k_size ());
-		memcpy (_data.data().get(), frame->right_j2k_data(), _data.size ());
-		break;
-	}
 }
 
+
 J2KImageProxy::J2KImageProxy (shared_ptr<cxml::Node> xml, shared_ptr<Socket> socket)
 	: _error (false)
 {
@@ -111,13 +104,14 @@ J2KImageProxy::J2KImageProxy (shared_ptr<cxml::Node> xml, shared_ptr<Socket> soc
 	if (xml->optional_number_child<int> ("Eye")) {
 		_eye = static_cast<dcp::Eye> (xml->number_child<int> ("Eye"));
 	}
-	_data = Data (xml->number_child<int> ("Size"));
+	shared_ptr<ArrayData> data(new ArrayData(xml->number_child<int>("Size")));
 	/* This only matters when we are using J2KImageProxy for the preview, which
 	   will never use this constructor (which is only used for passing data to
 	   encode servers).  So we can put anything in here.  It's a bit of a hack.
 	*/
 	_pixel_format = AV_PIX_FMT_XYZ12LE;
-	socket->read (_data.data().get (), _data.size ());
+	socket->read (data->data(), data->size());
+	_data = data;
 }
 
 int
@@ -144,7 +138,8 @@ J2KImageProxy::prepare (optional<dcp::Size> target_size) const
 	}
 
 	try {
-		shared_ptr<dcp::OpenJPEGImage> decompressed = dcp::decompress_j2k (const_cast<uint8_t*> (_data.data().get()), _data.size (), reduce);
+		/* XXX: should check that potentially trashing _data here doesn't matter */
+		shared_ptr<dcp::OpenJPEGImage> decompressed = dcp::decompress_j2k (const_cast<uint8_t*>(_data->data()), _data->size(), reduce);
 		_image.reset (new Image (_pixel_format, decompressed->size(), true));
 
 		int const shift = 16 - decompressed->precision (0);
@@ -202,13 +197,13 @@ J2KImageProxy::add_metadata (xmlpp::Node* node) const
 	if (_eye) {
 		node->add_child("Eye")->add_child_text (raw_convert<string> (static_cast<int> (_eye.get ())));
 	}
-	node->add_child("Size")->add_child_text (raw_convert<string> (_data.size ()));
+	node->add_child("Size")->add_child_text (raw_convert<string>(_data->size()));
 }
 
 void
 J2KImageProxy::write_to_socket (shared_ptr<Socket> socket) const
 {
-	socket->write (_data.data().get(), _data.size());
+	socket->write (_data->data(), _data->size());
 }
 
 bool
@@ -219,15 +214,11 @@ J2KImageProxy::same (shared_ptr<const ImageProxy> other) const
 		return false;
 	}
 
-	if (_data.size() != jp->_data.size()) {
-		return false;
-	}
-
-	return memcmp (_data.data().get(), jp->_data.data().get(), _data.size()) == 0;
+	return *_data == *jp->_data;
 }
 
-J2KImageProxy::J2KImageProxy (Data data, dcp::Size size, AVPixelFormat pixel_format)
-	: _data (data)
+J2KImageProxy::J2KImageProxy (ArrayData data, dcp::Size size, AVPixelFormat pixel_format)
+	: _data (new ArrayData(data))
 	, _size (size)
 	, _pixel_format (pixel_format)
 {
@@ -238,7 +229,7 @@ J2KImageProxy::J2KImageProxy (Data data, dcp::Size size, AVPixelFormat pixel_for
 size_t
 J2KImageProxy::memory_used () const
 {
-	size_t m = _data.size();
+	size_t m = _data->size();
 	if (_image) {
 		/* 3 components, 16-bits per pixel */
 		m += 3 * 2 * _image->size().width * _image->size().height;