Rearrange encoding so that the different methods / backends are not all crammed into DCPVideo.

12 files changed, 266 insertions, 174 deletions

diff --git a/src/lib/dcp_video.cc b/src/lib/dcp_video.cc
index 440571b76..161f74c57 100644
--- a/src/lib/dcp_video.cc
+++ b/src/lib/dcp_video.cc
@@ -32,7 +32,6 @@
 #include "config.h"
 #include "exceptions.h"
 #include "encode_server_description.h"
-#include "dcpomatic_socket.h"
 #include "image.h"
 #include "log.h"
 #include "dcpomatic_log.h"
@@ -48,7 +47,6 @@
 DCPOMATIC_DISABLE_WARNINGS
 #include <libxml++/libxml++.h>
 DCPOMATIC_ENABLE_WARNINGS
-#include <boost/asio.hpp>
 #include <boost/thread.hpp>
 #include <stdint.h>
 #include <iomanip>
@@ -117,95 +115,6 @@ DCPVideo::convert_to_xyz (shared_ptr<const PlayerVideo> frame, dcp::NoteHandler
 	return xyz;
 }
 
-/** J2K-encode this frame on the local host.
- *  @return Encoded data.
- */
-Data
-DCPVideo::encode_locally ()
-{
-	string const comment = Config::instance()->dcp_j2k_comment();
-
-	Data enc = dcp::compress_j2k (
-		convert_to_xyz (_frame, boost::bind(&Log::dcp_log, dcpomatic_log.get(), _1, _2)),
-		_j2k_bandwidth,
-		_frames_per_second,
-		_frame->eyes() == EYES_LEFT || _frame->eyes() == EYES_RIGHT,
-		_resolution == RESOLUTION_4K,
-		comment.empty() ? "libdcp" : comment
-		);
-
-	switch (_frame->eyes()) {
-	case EYES_BOTH:
-		LOG_DEBUG_ENCODE (N_("Finished locally-encoded frame %1 for mono"), _index);
-		break;
-	case EYES_LEFT:
-		LOG_DEBUG_ENCODE (N_("Finished locally-encoded frame %1 for L"), _index);
-		break;
-	case EYES_RIGHT:
-		LOG_DEBUG_ENCODE (N_("Finished locally-encoded frame %1 for R"), _index);
-		break;
-	default:
-		break;
-	}
-
-	return enc;
-}
-
-/** Send this frame to a remote server for J2K encoding, then read the result.
- *  @param serv Server to send to.
- *  @param timeout timeout in seconds.
- *  @return Encoded data.
- */
-Data
-DCPVideo::encode_remotely (EncodeServerDescription serv, int timeout)
-{
-	boost::asio::io_service io_service;
-	boost::asio::ip::tcp::resolver resolver (io_service);
-	boost::asio::ip::tcp::resolver::query query (serv.host_name(), raw_convert<string> (ENCODE_FRAME_PORT));
-	boost::asio::ip::tcp::resolver::iterator endpoint_iterator = resolver.resolve (query);
-
-	shared_ptr<Socket> socket (new Socket (timeout));
-
-	socket->connect (*endpoint_iterator);
-
-	/* Collect all XML metadata */
-	xmlpp::Document doc;
-	xmlpp::Element* root = doc.create_root_node ("EncodingRequest");
-	root->add_child("Version")->add_child_text (raw_convert<string> (SERVER_LINK_VERSION));
-	add_metadata (root);
-
-	LOG_DEBUG_ENCODE (N_("Sending frame %1 to remote"), _index);
-
-	{
-		Socket::WriteDigestScope ds (socket);
-
-		/* Send XML metadata */
-		string xml = doc.write_to_string ("UTF-8");
-		socket->write (xml.length() + 1);
-		socket->write ((uint8_t *) xml.c_str(), xml.length() + 1);
-
-		/* Send binary data */
-		LOG_TIMING("start-remote-send thread=%1", thread_id ());
-		_frame->write_to_socket (socket);
-	}
-
-	/* Read the response (JPEG2000-encoded data); this blocks until the data
-	   is ready and sent back.
-	*/
-	Socket::ReadDigestScope ds (socket);
-	LOG_TIMING("start-remote-encode thread=%1", thread_id ());
-	Data e (socket->read_uint32 ());
-	LOG_TIMING("start-remote-receive thread=%1", thread_id ());
-	socket->read (e.data().get(), e.size());
-	LOG_TIMING("finish-remote-receive thread=%1", thread_id ());
-	if (!ds.check()) {
-		throw NetworkError ("Checksums do not match");
-	}
-
-	LOG_DEBUG_ENCODE (N_("Finished remotely-encoded frame %1"), _index);
-
-	return e;
-}
 
 void
 DCPVideo::add_metadata (xmlpp::Element* el) const
@@ -217,11 +126,6 @@ DCPVideo::add_metadata (xmlpp::Element* el) const
 	_frame->add_metadata (el);
 }
 
-Eyes
-DCPVideo::eyes () const
-{
-	return _frame->eyes ();
-}
 
 /** @return true if this DCPVideo is definitely the same as another;
  *  (apart from the frame index), false if it is probably not.
diff --git a/src/lib/dcp_video.h b/src/lib/dcp_video.h
index 81ddc4470..49a858733 100644
--- a/src/lib/dcp_video.h
+++ b/src/lib/dcp_video.h
@@ -45,23 +45,32 @@ public:
 	DCPVideo (boost::shared_ptr<const PlayerVideo>, int, int, int, Resolution);
 	DCPVideo (boost::shared_ptr<const PlayerVideo>, cxml::ConstNodePtr);
 
-	dcp::Data encode_locally ();
-	dcp::Data encode_remotely (EncodeServerDescription, int timeout = 30);
+	boost::shared_ptr<const PlayerVideo> frame () const {
+		return _frame;
+	}
 
 	int index () const {
 		return _index;
 	}
 
-	Eyes eyes () const;
+	int frames_per_second () const {
+		return _frames_per_second;
+	}
+
+	int j2k_bandwidth () const {
+		return _j2k_bandwidth;
+	}
+
+	Resolution resolution () const {
+		return _resolution;
+	}
 
 	bool same (boost::shared_ptr<const DCPVideo> other) const;
+	void add_metadata (xmlpp::Element *) const;
 
 	static boost::shared_ptr<dcp::OpenJPEGImage> convert_to_xyz (boost::shared_ptr<const PlayerVideo> frame, dcp::NoteHandler note);
 
 private:
-
-	void add_metadata (xmlpp::Element *) const;
-
 	boost::shared_ptr<const PlayerVideo> _frame;
 	int _index;			 ///< frame index within the DCP's intrinsic duration
 	int _frames_per_second;		 ///< Frames per second that we will use for the DCP
diff --git a/src/lib/encode_server.cc b/src/lib/encode_server.cc
index f4224798b..85f3ca7b0 100644
--- a/src/lib/encode_server.cc
+++ b/src/lib/encode_server.cc
@@ -141,11 +141,11 @@ EncodeServer::process (shared_ptr<Socket> socket, struct timeval& after_read, st
 		throw NetworkError ("Checksums do not match");
 	}
 
-	DCPVideo dcp_video_frame (pvf, xml);
+	shared_ptr<DCPVideo> frame(new DCPVideo(pvf, xml));
 
 	gettimeofday (&after_read, 0);
 
-	Data encoded = dcp_video_frame.encode_locally ();
+	Data encoded = *_cpu_encoder.encode (frame);
 
 	gettimeofday (&after_encode, 0);
 
@@ -154,12 +154,12 @@ EncodeServer::process (shared_ptr<Socket> socket, struct timeval& after_read, st
 		socket->write (encoded.size());
 		socket->write (encoded.data().get(), encoded.size());
 	} catch (std::exception& e) {
-		cerr << "Send failed; frame " << dcp_video_frame.index() << "\n";
-		LOG_ERROR ("Send failed; frame %1", dcp_video_frame.index());
+		cerr << "Send failed; frame " << frame->index() << "\n";
+		LOG_ERROR ("Send failed; frame %1", frame->index());
 		throw;
 	}
 
-	return dcp_video_frame.index ();
+	return frame->index ();
 }
 
 void
diff --git a/src/lib/encode_server.h b/src/lib/encode_server.h
index a43cea7ef..af1ead2bb 100644
--- a/src/lib/encode_server.h
+++ b/src/lib/encode_server.h
@@ -27,6 +27,7 @@
 
 #include "server.h"
 #include "exception_store.h"
+#include "j2k_encoder_cpu_backend.h"
 #include <boost/thread.hpp>
 #include <boost/asio.hpp>
 #include <boost/thread/condition.hpp>
@@ -61,6 +62,8 @@ private:
 	bool _verbose;
 	int _num_threads;
 
+	J2KEncoderCPUBackend _cpu_encoder;
+
 	struct Broadcast {
 
 		Broadcast ()
diff --git a/src/lib/j2k_encoder.cc b/src/lib/j2k_encoder.cc
index 64cd38147..ef38aaa55 100644
--- a/src/lib/j2k_encoder.cc
+++ b/src/lib/j2k_encoder.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2019 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2020 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -23,6 +23,9 @@
  */
 
 #include "j2k_encoder.h"
+#include "j2k_encoder_backend.h"
+#include "j2k_encoder_cpu_backend.h"
+#include "j2k_encoder_remote_backend.h"
 #include "util.h"
 #include "film.h"
 #include "log.h"
@@ -57,6 +60,7 @@ using namespace dcpomatic;
 J2KEncoder::J2KEncoder (shared_ptr<const Film> film, shared_ptr<Writer> writer)
 	: _film (film)
 	, _history (200)
+	, _cpu_backend (new J2KEncoderCPUBackend())
 	, _writer (writer)
 {
 	servers_list_changed ();
@@ -123,13 +127,13 @@ J2KEncoder::end ()
 	     So just mop up anything left in the queue here.
 	*/
 
-	for (list<shared_ptr<DCPVideo> >::iterator i = _queue.begin(); i != _queue.end(); ++i) {
-		LOG_GENERAL (N_("Encode left-over frame %1"), (*i)->index ());
+	BOOST_FOREACH (shared_ptr<DCPVideo> i, _queue) {
+		LOG_GENERAL (N_("Encode left-over frame %1"), i->index());
 		try {
 			_writer->write (
-				(*i)->encode_locally(),
-				(*i)->index(),
-				(*i)->eyes()
+				*_cpu_backend->encode(i),
+				i->index(),
+				i->frame()->eyes()
 				);
 			frame_done ();
 		} catch (std::exception& e) {
@@ -258,20 +262,10 @@ J2KEncoder::terminate_threads ()
 }
 
 void
-J2KEncoder::encoder_thread (optional<EncodeServerDescription> server)
+J2KEncoder::encoder_thread (shared_ptr<J2KEncoderBackend> backend)
 try
 {
-	if (server) {
-		LOG_TIMING ("start-encoder-thread thread=%1 server=%2", thread_id (), server->host_name ());
-	} else {
-		LOG_TIMING ("start-encoder-thread thread=%1 server=localhost", thread_id ());
-	}
-
-	/* Number of seconds that we currently wait between attempts
-	   to connect to the server; not relevant for localhost
-	   encodings.
-	*/
-	int remote_backoff = 0;
+	LOG_TIMING ("start-encoder-thread thread=%1", thread_id());
 
 	while (true) {
 
@@ -291,50 +285,15 @@ try
 		{
 			boost::this_thread::disable_interruption dis;
 
-			LOG_TIMING ("encoder-pop thread=%1 frame=%2 eyes=%3", thread_id(), vf->index(), (int) vf->eyes ());
+			LOG_TIMING ("encoder-pop thread=%1 frame=%2 eyes=%3", thread_id(), vf->index(), (int) vf->frame()->eyes());
 			_queue.pop_front ();
 
 			lock.unlock ();
 
-			optional<Data> encoded;
-
-			/* We need to encode this input */
-			if (server) {
-				try {
-					encoded = vf->encode_remotely (server.get ());
-
-					if (remote_backoff > 0) {
-						LOG_GENERAL ("%1 was lost, but now she is found; removing backoff", server->host_name ());
-					}
-
-					/* This job succeeded, so remove any backoff */
-					remote_backoff = 0;
-
-				} catch (std::exception& e) {
-					if (remote_backoff < 60) {
-						/* back off more */
-						remote_backoff += 10;
-					}
-					LOG_ERROR (
-						N_("Remote encode of %1 on %2 failed (%3); thread sleeping for %4s"),
-						vf->index(), server->host_name(), e.what(), remote_backoff
-						);
-				}
-
-			} else {
-				try {
-					LOG_TIMING ("start-local-encode thread=%1 frame=%2", thread_id(), vf->index());
-					encoded = vf->encode_locally ();
-					LOG_TIMING ("finish-local-encode thread=%1 frame=%2", thread_id(), vf->index());
-				} catch (std::exception& e) {
-					/* This is very bad, so don't cope with it, just pass it on */
-					LOG_ERROR (N_("Local encode failed (%1)"), e.what ());
-					throw;
-				}
-			}
+			optional<Data> encoded = backend->encode (vf);
 
 			if (encoded) {
-				_writer->write (encoded.get(), vf->index (), vf->eyes ());
+				_writer->write (encoded.get(), vf->index (), vf->frame()->eyes());
 				frame_done ();
 			} else {
 				lock.lock ();
@@ -344,10 +303,6 @@ try
 			}
 		}
 
-		if (remote_backoff > 0) {
-			boost::this_thread::sleep (boost::posix_time::seconds (remote_backoff));
-		}
-
 		/* The queue might not be full any more, so notify anything that is waiting on that */
 		lock.lock ();
 		_full_condition.notify_all ();
@@ -375,10 +330,10 @@ J2KEncoder::servers_list_changed ()
 	if (!Config::instance()->only_servers_encode ()) {
 		for (int i = 0; i < Config::instance()->master_encoding_threads (); ++i) {
 #ifdef DCPOMATIC_LINUX
-			boost::thread* t = _threads->create_thread(boost::bind(&J2KEncoder::encoder_thread, this, optional<EncodeServerDescription>()));
+			boost::thread* t = _threads->create_thread(boost::bind(&J2KEncoder::encoder_thread, this, _cpu_backend));
 			pthread_setname_np (t->native_handle(), "encode-worker");
 #else
-			_threads->create_thread(boost::bind(&J2KEncoder::encoder_thread, this, optional<EncodeServerDescription>()));
+			_threads->create_thread(boost::bind(&J2KEncoder::encoder_thread, this, _cpu_backend));
 #endif
 		}
 	}
@@ -389,8 +344,9 @@ J2KEncoder::servers_list_changed ()
 		}
 
 		LOG_GENERAL (N_("Adding %1 worker threads for remote %2"), i.threads(), i.host_name ());
+		shared_ptr<J2KEncoderRemoteBackend> backend (new J2KEncoderRemoteBackend(i));
 		for (int j = 0; j < i.threads(); ++j) {
-			_threads->create_thread(boost::bind(&J2KEncoder::encoder_thread, this, i));
+			_threads->create_thread(boost::bind(&J2KEncoder::encoder_thread, this, backend));
 		}
 	}
 
diff --git a/src/lib/j2k_encoder.h b/src/lib/j2k_encoder.h
index d56fc1aec..df23a5bae 100644
--- a/src/lib/j2k_encoder.h
+++ b/src/lib/j2k_encoder.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2016 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2020 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -45,6 +45,10 @@ class DCPVideo;
 class Writer;
 class Job;
 class PlayerVideo;
+class J2KEncoderBackend;
+class J2KEncoderCPUBackend;
+class J2KEncoderRemoteBackend;
+
 
 /** @class J2KEncoder
  *  @brief Class to manage encoding to J2K.
@@ -79,16 +83,17 @@ private:
 
 	void frame_done ();
 
-	void encoder_thread (boost::optional<EncodeServerDescription>);
+	void encoder_thread (boost::shared_ptr<J2KEncoderBackend> backend);
 	void terminate_threads ();
 
-	/** Film that we are encoding */
 	boost::shared_ptr<const Film> _film;
 
 	EventHistory _history;
 
 	boost::shared_ptr<boost::thread_group> _threads;
 
+	boost::shared_ptr<J2KEncoderCPUBackend> _cpu_backend;
+
 	mutable boost::mutex _queue_mutex;
 	std::list<boost::shared_ptr<DCPVideo> > _queue;
 	/** condition to manage thread wakeups when we have nothing to do */
diff --git a/src/lib/j2k_encoder_backend.h b/src/lib/j2k_encoder_backend.h
new file mode 100644
index 000000000..7688e5f15
--- /dev/null
+++ b/src/lib/j2k_encoder_backend.h
@@ -0,0 +1,19 @@
+#ifndef DCPOMATIC_J2K_ENCODER_BACKEND_H
+#define DCPOMATIC_J2K_ENCODER_BACKEND_H
+
+#include <dcp/data.h>
+#include <boost/noncopyable.hpp>
+#include <boost/optional.hpp>
+#include <boost/shared_ptr.hpp>
+
+
+class DCPVideo;
+
+
+class J2KEncoderBackend : public boost::noncopyable
+{
+public:
+	virtual boost::optional<dcp::Data> encode (boost::shared_ptr<DCPVideo> video) = 0;
+};
+
+#endif
diff --git a/src/lib/j2k_encoder_cpu_backend.cc b/src/lib/j2k_encoder_cpu_backend.cc
new file mode 100644
index 000000000..732913c06
--- /dev/null
+++ b/src/lib/j2k_encoder_cpu_backend.cc
@@ -0,0 +1,56 @@
+#include "config.h"
+#include "cross.h"
+#include "dcp_video.h"
+#include "dcpomatic_log.h"
+#include "j2k_encoder_cpu_backend.h"
+#include "player_video.h"
+#include <dcp/j2k.h>
+
+#include "i18n.h"
+
+
+using std::string;
+using boost::optional;
+using boost::shared_ptr;
+using dcp::Data;
+
+
+optional<Data>
+J2KEncoderCPUBackend::encode (shared_ptr<DCPVideo> video)
+{
+	try {
+		LOG_TIMING ("start-local-encode thread=%1 frame=%2", thread_id(), video->index());
+		string const comment = Config::instance()->dcp_j2k_comment();
+
+		Data enc = dcp::compress_j2k (
+			DCPVideo::convert_to_xyz (video->frame(), boost::bind(&Log::dcp_log, dcpomatic_log.get(), _1, _2)),
+			video->j2k_bandwidth(),
+			video->frames_per_second(),
+			video->frame()->eyes() == EYES_LEFT || video->frame()->eyes() == EYES_RIGHT,
+			video->resolution() == RESOLUTION_4K,
+			comment.empty() ? "libdcp" : comment
+			);
+
+		switch (video->frame()->eyes()) {
+		case EYES_BOTH:
+			LOG_DEBUG_ENCODE (N_("Finished locally-encoded frame %1 for mono"), video->index());
+			break;
+		case EYES_LEFT:
+			LOG_DEBUG_ENCODE (N_("Finished locally-encoded frame %1 for L"), video->index());
+			break;
+		case EYES_RIGHT:
+			LOG_DEBUG_ENCODE (N_("Finished locally-encoded frame %1 for R"), video->index());
+			break;
+		default:
+			break;
+		}
+
+		LOG_TIMING ("finish-local-encode thread=%1 frame=%2", thread_id(), video->index());
+		return enc;
+	} catch (std::exception& e) {
+		/* This is very bad, so don't cope with it, just pass it on */
+		LOG_ERROR (N_("Local encode failed (%1)"), e.what());
+		throw;
+	}
+}
+
diff --git a/src/lib/j2k_encoder_cpu_backend.h b/src/lib/j2k_encoder_cpu_backend.h
new file mode 100644
index 000000000..75d7c97a7
--- /dev/null
+++ b/src/lib/j2k_encoder_cpu_backend.h
@@ -0,0 +1,14 @@
+#ifndef DCPOMATIC_J2K_ENCODER_CPU_BACKEND_H
+#define DCPOMATIC_J2K_ENCODER_CPU_BACKEND_H
+
+
+#include "j2k_encoder_backend.h"
+
+
+class J2KEncoderCPUBackend : public J2KEncoderBackend
+{
+public:
+	boost::optional<dcp::Data> encode (boost::shared_ptr<DCPVideo> video);
+};
+
+#endif
diff --git a/src/lib/j2k_encoder_remote_backend.cc b/src/lib/j2k_encoder_remote_backend.cc
new file mode 100644
index 000000000..831134718
--- /dev/null
+++ b/src/lib/j2k_encoder_remote_backend.cc
@@ -0,0 +1,108 @@
+#include "config.h"
+#include "cross.h"
+#include "dcp_video.h"
+#include "dcpomatic_log.h"
+#include "dcpomatic_socket.h"
+#include "encode_server_description.h"
+#include "j2k_encoder_remote_backend.h"
+#include "player_video.h"
+#include "warnings.h"
+#include <dcp/raw_convert.h>
+DCPOMATIC_DISABLE_WARNINGS
+#include <libxml++/libxml++.h>
+DCPOMATIC_ENABLE_WARNINGS
+#include <boost/asio.hpp>
+#include <boost/thread.hpp>
+
+#include "i18n.h"
+
+
+using std::string;
+using boost::optional;
+using boost::shared_ptr;
+using dcp::Data;
+using dcp::raw_convert;
+
+
+J2KEncoderRemoteBackend::J2KEncoderRemoteBackend (EncodeServerDescription server)
+	: _server (server)
+	, _backoff (0)
+{
+
+}
+
+
+optional<Data>
+J2KEncoderRemoteBackend::encode (shared_ptr<DCPVideo> video)
+{
+	int const timeout = 30;
+
+	try {
+		boost::asio::io_service io_service;
+		boost::asio::ip::tcp::resolver resolver (io_service);
+		boost::asio::ip::tcp::resolver::query query (_server.host_name(), raw_convert<string>(ENCODE_FRAME_PORT));
+		boost::asio::ip::tcp::resolver::iterator endpoint_iterator = resolver.resolve (query);
+
+		shared_ptr<Socket> socket (new Socket(timeout));
+
+		socket->connect (*endpoint_iterator);
+
+		/* Collect all XML metadata */
+		xmlpp::Document doc;
+		xmlpp::Element* root = doc.create_root_node ("EncodingRequest");
+		root->add_child("Version")->add_child_text(raw_convert<string> (SERVER_LINK_VERSION));
+		video->add_metadata (root);
+
+		LOG_DEBUG_ENCODE (N_("Sending frame %1 to remote"), video->index());
+
+		{
+			Socket::WriteDigestScope ds (socket);
+
+			/* Send XML metadata */
+			string xml = doc.write_to_string ("UTF-8");
+			socket->write (xml.length() + 1);
+			socket->write ((uint8_t *) xml.c_str(), xml.length() + 1);
+
+			/* Send binary data */
+			LOG_TIMING("start-remote-send thread=%1", thread_id());
+			video->frame()->write_to_socket(socket);
+		}
+
+		/* Read the response (JPEG2000-encoded data); this blocks until the data
+		   is ready and sent back.
+		*/
+		Socket::ReadDigestScope ds (socket);
+		LOG_TIMING("start-remote-encode thread=%1", thread_id());
+		Data e (socket->read_uint32 ());
+		LOG_TIMING("start-remote-receive thread=%1", thread_id());
+		socket->read (e.data().get(), e.size());
+		LOG_TIMING("finish-remote-receive thread=%1", thread_id());
+		if (!ds.check()) {
+			throw NetworkError ("Checksums do not match");
+		}
+
+		LOG_DEBUG_ENCODE (N_("Finished remotely-encoded frame %1"), video->index());
+
+		if (_backoff > 0) {
+			LOG_GENERAL ("%1 was lost, but now she is found; removing backoff", _server.host_name());
+		}
+
+		/* This job succeeded, so remove any backoff */
+		_backoff = 0;
+
+		return e;
+
+	} catch (std::exception& e) {
+		if (_backoff < 60) {
+			_backoff += 10;
+		}
+		LOG_ERROR (
+			N_("Remote encode of %1 on %2 failed (%3); thread sleeping for %4s"),
+			video->index(), _server.host_name(), e.what(), _backoff
+			);
+
+		boost::this_thread::sleep (boost::posix_time::seconds(_backoff));
+		return optional<Data>();
+	}
+}
+
diff --git a/src/lib/j2k_encoder_remote_backend.h b/src/lib/j2k_encoder_remote_backend.h
new file mode 100644
index 000000000..5e62cd9a9
--- /dev/null
+++ b/src/lib/j2k_encoder_remote_backend.h
@@ -0,0 +1,16 @@
+#include "encode_server_description.h"
+#include "j2k_encoder_backend.h"
+
+
+class J2KEncoderRemoteBackend : public J2KEncoderBackend
+{
+public:
+	J2KEncoderRemoteBackend (EncodeServerDescription server);
+	boost::optional<dcp::Data> encode (boost::shared_ptr<DCPVideo> video);
+
+private:
+	EncodeServerDescription _server;
+	int _backoff;
+};
+
+
diff --git a/src/lib/wscript b/src/lib/wscript
index 3b14f8738..59cc145a2 100644
--- a/src/lib/wscript
+++ b/src/lib/wscript
@@ -125,9 +125,11 @@ sources = """
           image_proxy.cc
           isdcf_metadata.cc
           j2k_image_proxy.cc
+          j2k_encoder.cc
+          j2k_encoder_cpu_backend.cc
+          j2k_encoder_remote_backend.cc
           job.cc
           job_manager.cc
-          j2k_encoder.cc
           json_server.cc
           kdm_with_metadata.cc
           kdm_recipient.cc