1 files changed, 106 insertions, 0 deletions
diff --git a/Swiften/ScreenSharing/ReferencePictureSelection.cpp b/Swiften/ScreenSharing/ReferencePictureSelection.cpp
new file mode 100644
index 0000000..dc2a81e
--- /dev/null
+++ b/Swiften/ScreenSharing/ReferencePictureSelection.cpp
@@ -0,0 +1,106 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <Swiften/ScreenSharing/ReferencePictureSelection.h>
+#include <Swiften/Base/Log.h>
+
+#include "vpx/vpx_encoder.h"
+#include "vpx/vp8cx.h"
+
+namespace Swift {
+
+ReferencePictureSelection::ReferencePictureSelection()
+	: update_golden_next_(true),
+	  established_golden_(false),
+	  received_ack_(false),
+	  last_sent_ref_picture_id_(0),
+	  established_ref_picture_id_(0),
+	  send_refresh(false) {
+}
+
+void ReferencePictureSelection::ReceivedRPSI(int rpsi_picture_id) {
+	// Assume RPSI is signaled with 7 bits.
+	SWIFT_LOG(debug) << "ReceivedRPSI: " << rpsi_picture_id  << ", " << last_sent_ref_picture_id_ << std::endl;
+	if ((rpsi_picture_id & 127) == (last_sent_ref_picture_id_ & 127)) {
+		// Remote peer has received our last reference frame, switch frame type.
+		received_ack_ = true;
+		established_golden_ = update_golden_next_;
+		update_golden_next_ = !update_golden_next_;
+		established_ref_picture_id_ = last_sent_ref_picture_id_;
+		SWIFT_LOG(debug) << "Ref established: " << established_ref_picture_id_ << std::endl;
+	}
+}
+
+void ReferencePictureSelection::ReceivedSLI() {
+	send_refresh = true;
+}
+
+int ReferencePictureSelection::EncodeFlags(int picture_id) {
+	int flags = 0;
+	// We can't refresh the decoder until we have established the key frame.
+	if (send_refresh/* && received_ack_*/) {
+		flags = VPX_EFLAG_FORCE_KF;
+//		flags |= VPX_EFLAG_FORCE_KF;
+		/*
+		flags |= VP8_EFLAG_NO_REF_LAST;  // Don't reference the last frame
+
+		if (established_golden_)
+			flags |= VP8_EFLAG_NO_REF_ARF;  // Don't reference the alt-ref frame.
+		else
+			flags |= VP8_EFLAG_NO_REF_GF;  // Don't reference the golden frame
+			*/
+
+
+
+		/*SWIFT_LOG(debug) << "Send refresh" << std::endl;
+		if (established_golden_) {
+			flags |= VP8_EFLAG_FORCE_ARF;
+			flags |= VP8_EFLAG_NO_UPD_GF;
+			flags |= VP8_EFLAG_NO_REF_ARF;
+		} else {
+			flags |= VP8_EFLAG_FORCE_GF;
+			flags |= VP8_EFLAG_NO_UPD_ARF;
+			flags |= VP8_EFLAG_NO_REF_GF;
+		}*/
+	}
+	send_refresh = false;
+
+	// Don't send reference frame updates until we have an established reference.
+	if (received_ack_ && picture_id % 8 == 0 && false) {
+		flags |= VP8_EFLAG_NO_REF_LAST;  // Don't reference the last frame.
+		SWIFT_LOG(debug) << "Send reference : " << std::boolalpha << update_golden_next_ << std::endl;
+		if (update_golden_next_) {
+			flags |= VP8_EFLAG_FORCE_GF;  // Update the golden reference.
+			flags |= VP8_EFLAG_NO_UPD_ARF;  // Don't update alt-ref.
+			flags |= VP8_EFLAG_NO_REF_GF;  // Don't reference the golden frame.
+		} else {
+			flags |= VP8_EFLAG_FORCE_ARF;  // Update the alt-ref reference.
+			flags |= VP8_EFLAG_NO_UPD_GF;  // Don't update the golden frame.
+			flags |= VP8_EFLAG_NO_REF_ARF;  // Don't reference the alt-ref frame.
+		}
+	} else {
+		// No update of golden or alt-ref. We can therefore freely reference the
+		// established reference frame and the last frame.
+		if (established_golden_)
+			flags |= VP8_EFLAG_NO_REF_ARF;  // Don't reference the alt-ref frame.
+		else
+			flags |= VP8_EFLAG_NO_REF_GF;   // Don't reference the golden frame.
+		flags |= VP8_EFLAG_NO_UPD_GF;  // Don't update the golden frame.
+		flags |= VP8_EFLAG_NO_UPD_ARF;  // Don't update the alt-ref frame.
+	}
+	return flags;
+}
+
+void ReferencePictureSelection::refFrameSent(int picture_id) {
+	last_sent_ref_picture_id_ = picture_id;
+	received_ack_ = false;
+}
+
+}