mollyim/webrtc
1
0
Fork 0
mirror of https://github.com/mollyim/webrtc.git synced 2025-05-12 21:30:45 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

Allow empty video layer allocation extension

Browse source 
This patch adds support for sending zero video layer allocations
header extensions. This can be used to signal that a stream is
turned off.

Bug: webrtc:12000
Change-Id: Id18fbbff2216ca23179c58ef7bbe2ebea5e242af
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/212743
Commit-Queue: Jonas Oreland <jonaso@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33541}
This commit is contained in:
Jonas Oreland 2021-03-23 11:11:56 +01:00 committed by Commit Bot
parent fa4db49532
commit 93ee168671
3 changed files with 41 additions and 9 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
docs/native-code/rtp-hdrext/video-layers-allocation00/README.md
View file

@ -80,3 +80,5 @@ extension size. Encoded (width - 1), 16-bit, (height - 1), 16-bit, max frame
rate 8-bit per spatial layer per RTP stream. Values are stored in (RTP stream
id, spatial id) ascending order.
An empty layer allocation (i.e nothing sent on ssrc) is encoded as
special case with a single 0 byte.

24
modules/rtp_rtcp/source/rtp_video_layers_allocation_extension.cc
View file

@ -201,17 +201,21 @@ SpatialLayersBitmasks SpatialLayersBitmasksPerRtpStream(
// Encoded (width - 1), 16-bit, (height - 1), 16-bit, max frame rate 8-bit
// per spatial layer per RTP stream.
// Values are stored in (RTP stream id, spatial id) ascending order.
//
// An empty layer allocation (i.e nothing sent on ssrc) is encoded as
// special case with a single 0 byte.
bool RtpVideoLayersAllocationExtension::Write(
rtc::ArrayView<uint8_t> data,
const VideoLayersAllocation& allocation) {
if (allocation.active_spatial_layers.empty()) {
return false;
}
RTC_DCHECK(AllocationIsValid(allocation));
RTC_DCHECK_GE(data.size(), ValueSize(allocation));
if (allocation.active_spatial_layers.empty()) {
data[0] = 0;
return true;
}
SpatialLayersBitmasks slb = SpatialLayersBitmasksPerRtpStream(allocation);
uint8_t* write_at = data.data();
// First half of the header byte.
@ -276,10 +280,18 @@ bool RtpVideoLayersAllocationExtension::Parse(
if (data.empty() || allocation == nullptr) {
return false;
}
allocation->active_spatial_layers.clear();
const uint8_t* read_at = data.data();
const uint8_t* const end = data.data() + data.size();
allocation->active_spatial_layers.clear();
if (data.size() == 1 && *read_at == 0) {
allocation->rtp_stream_index = 0;
allocation->resolution_and_frame_rate_is_valid = true;
return true;
}
// Header byte.
allocation->rtp_stream_index = *read_at >> 6;
int num_rtp_streams = 1 + ((*read_at >> 4) & 0b11);
@ -374,7 +386,7 @@ bool RtpVideoLayersAllocationExtension::Parse(
size_t RtpVideoLayersAllocationExtension::ValueSize(
const VideoLayersAllocation& allocation) {
if (allocation.active_spatial_layers.empty()) {
return 0;
return 1;
}
size_t result = 1; // header
SpatialLayersBitmasks slb = SpatialLayersBitmasksPerRtpStream(allocation);

24
modules/rtp_rtcp/source/rtp_video_layers_allocation_extension_unittest.cc
View file

@ -19,15 +19,33 @@
namespace webrtc {
namespace {
TEST(RtpVideoLayersAllocationExtension,
WriteEmptyLayersAllocationReturnsFalse) {
TEST(RtpVideoLayersAllocationExtension, WriteEmptyLayersAllocationReturnsTrue) {
VideoLayersAllocation written_allocation;
rtc::Buffer buffer(
RtpVideoLayersAllocationExtension::ValueSize(written_allocation));
EXPECT_FALSE(
EXPECT_TRUE(
RtpVideoLayersAllocationExtension::Write(buffer, written_allocation));
}
TEST(RtpVideoLayersAllocationExtension,
CanWriteAndParseLayersAllocationWithZeroSpatialLayers) {
// We require the resolution_and_frame_rate_is_valid to be set to true in
// order to send an "empty" allocation.
VideoLayersAllocation written_allocation;
written_allocation.resolution_and_frame_rate_is_valid = true;
written_allocation.rtp_stream_index = 0;
rtc::Buffer buffer(
RtpVideoLayersAllocationExtension::ValueSize(written_allocation));
EXPECT_TRUE(
RtpVideoLayersAllocationExtension::Write(buffer, written_allocation));
VideoLayersAllocation parsed_allocation;
EXPECT_TRUE(
RtpVideoLayersAllocationExtension::Parse(buffer, &parsed_allocation));
EXPECT_EQ(written_allocation, parsed_allocation);
}
TEST(RtpVideoLayersAllocationExtension,
CanWriteAndParse2SpatialWith2TemporalLayers) {
VideoLayersAllocation written_allocation;