Enable multithreaded OpenH264 encoding behind field trial

This uses the field trial introduced is crbug.com/1406331 and
extends the usage to OpenH264. This simplifies experimentation
whether this change improves performance without requiring
multi-slice encoding.

BUG=webrtc:14368

Change-Id: I0031e59059f7113dd5453234869c957d46f311bb
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/294340
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Philipp Hancke <phancke@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#39371}
This commit is contained in:
Philipp Hancke 2023-02-20 15:41:23 +01:00 committed by WebRTC LUCI CQ
parent b3c5bdb85a
commit b660b7a89c
3 changed files with 30 additions and 16 deletions

View file

@ -330,8 +330,8 @@ class RTC_EXPORT VideoEncoder {
Capabilities capabilities; Capabilities capabilities;
int number_of_cores; int number_of_cores;
size_t max_payload_size; size_t max_payload_size;
// Experimental API - currently only supported by LibvpxVp8Encoder. // Experimental API - currently only supported by LibvpxVp8Encoder and
// If set, limits the number of encoder threads. // the OpenH264 encoder. If set, limits the number of encoder threads.
absl::optional<int> encoder_thread_limit; absl::optional<int> encoder_thread_limit;
}; };

View file

@ -56,19 +56,30 @@ enum H264EncoderImplEvent {
kH264EncoderEventMax = 16, kH264EncoderEventMax = 16,
}; };
int NumberOfThreads(int width, int height, int number_of_cores) { int NumberOfThreads(absl::optional<int> encoder_thread_limit,
int width,
int height,
int number_of_cores) {
// TODO(hbos): In Chromium, multiple threads do not work with sandbox on Mac, // TODO(hbos): In Chromium, multiple threads do not work with sandbox on Mac,
// see crbug.com/583348. Until further investigated, only use one thread. // see crbug.com/583348. Until further investigated, only use one thread.
// if (width * height >= 1920 * 1080 && number_of_cores > 8) { // While this limitation is gone, this changes the bitstream format (see
// return 8; // 8 threads for 1080p on high perf machines. // bugs.webrtc.org/14368) so still guarded by field trial to allow for
// } else if (width * height > 1280 * 960 && number_of_cores >= 6) { // experimentation using th experimental
// return 3; // 3 threads for 1080p. // WebRTC-VideoEncoderSettings/encoder_thread_limit trial.
// } else if (width * height > 640 * 480 && number_of_cores >= 3) { if (encoder_thread_limit.has_value()) {
// return 2; // 2 threads for qHD/HD. int limit = encoder_thread_limit.value();
// } else { RTC_DCHECK_GE(limit, 1);
// return 1; // 1 thread for VGA or less. if (width * height >= 1920 * 1080 && number_of_cores > 8) {
// } return std::min(limit, 8); // 8 threads for 1080p on high perf machines.
// TODO(sprang): Also check sSliceArgument.uiSliceNum om GetEncoderPrams(), } else if (width * height > 1280 * 960 && number_of_cores >= 6) {
return std::min(limit, 3); // 3 threads for 1080p.
} else if (width * height > 640 * 480 && number_of_cores >= 3) {
return std::min(limit, 2); // 2 threads for qHD/HD.
} else {
return 1; // 1 thread for VGA or less.
}
}
// TODO(sprang): Also check sSliceArgument.uiSliceNum on GetEncoderParams(),
// before enabling multithreading here. // before enabling multithreading here.
return 1; return 1;
} }
@ -223,8 +234,9 @@ int32_t H264EncoderImpl::InitEncode(const VideoCodec* inst,
configurations_.resize(number_of_streams); configurations_.resize(number_of_streams);
tl0sync_limit_.resize(number_of_streams); tl0sync_limit_.resize(number_of_streams);
number_of_cores_ = settings.number_of_cores;
max_payload_size_ = settings.max_payload_size; max_payload_size_ = settings.max_payload_size;
number_of_cores_ = settings.number_of_cores;
encoder_thread_limit_ = settings.encoder_thread_limit;
codec_ = *inst; codec_ = *inst;
// Code expects simulcastStream resolutions to be correct, make sure they are // Code expects simulcastStream resolutions to be correct, make sure they are
@ -626,8 +638,9 @@ SEncParamExt H264EncoderImpl::CreateEncoderParams(size_t i) const {
// 0: auto (dynamic imp. internal encoder) // 0: auto (dynamic imp. internal encoder)
// 1: single thread (default value) // 1: single thread (default value)
// >1: number of threads // >1: number of threads
encoder_params.iMultipleThreadIdc = NumberOfThreads( encoder_params.iMultipleThreadIdc =
encoder_params.iPicWidth, encoder_params.iPicHeight, number_of_cores_); NumberOfThreads(encoder_thread_limit_, encoder_params.iPicWidth,
encoder_params.iPicHeight, number_of_cores_);
// The base spatial layer 0 is the only one we use. // The base spatial layer 0 is the only one we use.
encoder_params.sSpatialLayers[0].iVideoWidth = encoder_params.iPicWidth; encoder_params.sSpatialLayers[0].iVideoWidth = encoder_params.iPicWidth;
encoder_params.sSpatialLayers[0].iVideoHeight = encoder_params.iPicHeight; encoder_params.sSpatialLayers[0].iVideoHeight = encoder_params.iPicHeight;

View file

@ -110,6 +110,7 @@ class H264EncoderImpl : public H264Encoder {
H264PacketizationMode packetization_mode_; H264PacketizationMode packetization_mode_;
size_t max_payload_size_; size_t max_payload_size_;
int32_t number_of_cores_; int32_t number_of_cores_;
absl::optional<int> encoder_thread_limit_;
EncodedImageCallback* encoded_image_callback_; EncodedImageCallback* encoded_image_callback_;
bool has_reported_init_; bool has_reported_init_;