Frame marking RTP header extension (PART 1: implement extension)
Bug: webrtc:7765
Change-Id: I23896d121afd6be4bce5ff4deaf736149efebcdb
Reviewed-on: https://webrtc-review.googlesource.com/85200
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24695}diff --git a/modules/rtp_rtcp/source/rtp_header_extensions.cc b/modules/rtp_rtcp/source/rtp_header_extensions.cc
index 2dba4d7..e9e4d50 100644
--- a/modules/rtp_rtcp/source/rtp_header_extensions.cc
+++ b/modules/rtp_rtcp/source/rtp_header_extensions.cc
@@ -350,6 +350,86 @@
return true;
}
+// Frame Marking.
+//
+// Meta-information about an RTP stream outside the encrypted media payload,
+// useful for an RTP switch to do codec-agnostic selective forwarding
+// without decrypting the payload.
+//
+// For non-scalable streams:
+// 0 1
+// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+// | ID | L = 0 |S|E|I|D|0 0 0 0|
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//
+// For scalable streams:
+// 0 1 2 3
+// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+// | ID | L = 2 |S|E|I|D|B| TID | LID | TL0PICIDX |
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+constexpr RTPExtensionType FrameMarkingExtension::kId;
+constexpr const char FrameMarkingExtension::kUri[];
+
+bool FrameMarkingExtension::IsScalable(uint8_t temporal_id, uint8_t layer_id) {
+ return temporal_id != kNoTemporalIdx || layer_id != kNoSpatialIdx;
+}
+
+bool FrameMarkingExtension::Parse(rtc::ArrayView<const uint8_t> data,
+ FrameMarking* frame_marking) {
+ RTC_DCHECK(frame_marking);
+
+ if (data.size() != 1 && data.size() != 3)
+ return false;
+
+ frame_marking->start_of_frame = (data[0] & 0x80) != 0;
+ frame_marking->end_of_frame = (data[0] & 0x40) != 0;
+ frame_marking->independent_frame = (data[0] & 0x20) != 0;
+ frame_marking->discardable_frame = (data[0] & 0x10) != 0;
+
+ if (data.size() == 3) {
+ frame_marking->base_layer_sync = (data[0] & 0x08) != 0;
+ frame_marking->temporal_id = data[0] & 0x7;
+ frame_marking->layer_id = data[1];
+ frame_marking->tl0_pic_idx = data[2];
+ } else {
+ // non-scalable
+ frame_marking->base_layer_sync = false;
+ frame_marking->temporal_id = kNoTemporalIdx;
+ frame_marking->layer_id = kNoSpatialIdx;
+ frame_marking->tl0_pic_idx = 0;
+ }
+ return true;
+}
+
+size_t FrameMarkingExtension::ValueSize(const FrameMarking& frame_marking) {
+ if (IsScalable(frame_marking.temporal_id, frame_marking.layer_id))
+ return 3;
+ else
+ return 1;
+}
+
+bool FrameMarkingExtension::Write(rtc::ArrayView<uint8_t> data,
+ const FrameMarking& frame_marking) {
+ RTC_DCHECK_GE(data.size(), 1);
+ RTC_CHECK_LE(frame_marking.temporal_id, 0x07);
+ data[0] = frame_marking.start_of_frame ? 0x80 : 0x00;
+ data[0] |= frame_marking.end_of_frame ? 0x40 : 0x00;
+ data[0] |= frame_marking.independent_frame ? 0x20 : 0x00;
+ data[0] |= frame_marking.discardable_frame ? 0x10 : 0x00;
+
+ if (IsScalable(frame_marking.temporal_id, frame_marking.layer_id)) {
+ RTC_DCHECK_EQ(data.size(), 3);
+ data[0] |= frame_marking.base_layer_sync ? 0x08 : 0x00;
+ data[0] |= frame_marking.temporal_id & 0x07;
+ data[1] = frame_marking.layer_id;
+ data[2] = frame_marking.tl0_pic_idx;
+ }
+ return true;
+}
+
bool BaseRtpStringExtension::Parse(rtc::ArrayView<const uint8_t> data,
StringRtpHeaderExtension* str) {
if (data.empty() || data[0] == 0) // Valid string extension can't be empty.