diff --git a/modules/rtp_rtcp/source/rtp_video_layers_allocation_extension.cc b/modules/rtp_rtcp/source/rtp_video_layers_allocation_extension.cc index 5172ed4ce7..d44cb56205 100644 --- a/modules/rtp_rtcp/source/rtp_video_layers_allocation_extension.cc +++ b/modules/rtp_rtcp/source/rtp_video_layers_allocation_extension.cc @@ -184,16 +184,12 @@ bool RtpVideoLayersAllocationExtension::Write( } ++write_at; - { // Number of temporal layers. + { // Number of temporal layers per spatial layer (at most kMaxSpatialIds). + static_assert(VideoLayersAllocation::kMaxSpatialIds == 4); int bit_offset = 8; *write_at = 0; for (const auto& layer : allocation.active_spatial_layers) { - if (bit_offset == 0) { - bit_offset = 6; - *++write_at = 0; - } else { - bit_offset -= 2; - } + bit_offset -= 2; *write_at |= ((layer.target_bitrate_per_temporal_layer.size() - 1) << bit_offset); } @@ -269,8 +265,9 @@ bool RtpVideoLayersAllocationExtension::Parse( return false; } - // Read number of temporal layers, - // Create `allocation->active_spatial_layers` while iterating though it. + // Read number of temporal layers per spatial layer (at most kMaxSpatialIds), + // create `allocation->active_spatial_layers` while iterating though it. + static_assert(VideoLayersAllocation::kMaxSpatialIds == 4); int bit_offset = 8; for (int stream_idx = 0; stream_idx < num_rtp_streams; ++stream_idx) { for (int sid = 0; sid < VideoLayersAllocation::kMaxSpatialIds; ++sid) { @@ -278,14 +275,7 @@ bool RtpVideoLayersAllocationExtension::Parse( continue; } - if (bit_offset == 0) { - bit_offset = 6; - if (++read_at == end) { - return false; - } - } else { - bit_offset -= 2; - } + bit_offset -= 2; int num_temporal_layers = 1 + ((*read_at >> bit_offset) & 0b11); allocation->active_spatial_layers.emplace_back(); auto& layer = allocation->active_spatial_layers.back();