Refactor encoder-complexity param in VideoCodec w/backward compatibility

Move complexity parameter to the main VideoCodec class to enable
additional video codecs to use the parameter without creating a new
codec-specific structure.

Bug: webrtc:13694
Change-Id: Icb7cf640b178875d799f39ade8b5084e3222bb1c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/251921
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Michael Horowitz <mhoro@google.com>
Cr-Commit-Position: refs/heads/main@{#36040}

api/video_codecs/video_codec.cc

@@ -139,4 +139,23 @@ VideoCodecType PayloadStringToCodecType(const std::string& name) {
   return kVideoCodecGeneric;
 }
 
+VideoCodecComplexity VideoCodec::GetVideoEncoderComplexity() const {
+  if (complexity_.has_value()) {
+    return complexity_.value();
+  }
+  switch (codecType) {
+    case kVideoCodecVP8:
+      return VP8().complexity;
+    case kVideoCodecVP9:
+      return VP9().complexity;
+    default:
+      return VideoCodecComplexity::kComplexityNormal;
+  }
+}
+
+void VideoCodec::SetVideoEncoderComplexity(
+    VideoCodecComplexity complexity_setting) {
+  complexity_ = complexity_setting;
+}
+
 }  // namespace webrtc

api/video_codecs/video_codec.h

@@ -109,6 +109,9 @@ class RTC_EXPORT VideoCodec {
     scalability_mode_ = std::string(scalability_mode);
   }
 
+  VideoCodecComplexity GetVideoEncoderComplexity() const;
+  void SetVideoEncoderComplexity(VideoCodecComplexity complexity_setting);
+
   // Public variables. TODO(hta): Make them private with accessors.
   VideoCodecType codecType;
 
@@ -169,6 +172,9 @@ class RTC_EXPORT VideoCodec {
   // This will allow removing the VideoCodec* types from this file.
   VideoCodecUnion codec_specific_;
   std::string scalability_mode_;
+  // 'complexity_' indicates the CPU capability of the client. It's used to
+  // determine encoder CPU complexity (e.g., cpu_used for VP8, VP9. and AV1).
+  absl::optional<VideoCodecComplexity> complexity_;
 };
 
 }  // namespace webrtc

media/engine/simulcast_encoder_adapter.cc

@@ -791,8 +791,8 @@ webrtc::VideoCodec SimulcastEncoderAdapter::MakeStreamCodec(
       // kComplexityHigher, which maps to cpu_used = -4.
       int pixels_per_frame = codec_params.width * codec_params.height;
       if (pixels_per_frame < 352 * 288) {
-        codec_params.VP8()->complexity =
+        codec_params.SetVideoEncoderComplexity(
-            webrtc::VideoCodecComplexity::kComplexityHigher;
+            webrtc::VideoCodecComplexity::kComplexityHigher);
       }
       // Turn off denoising for all streams but the highest resolution.
       codec_params.VP8()->denoisingOn = false;

media/engine/simulcast_encoder_adapter_unittest.cc

@@ -502,7 +502,8 @@ class TestSimulcastEncoderAdapterFake : public ::testing::Test,
     EXPECT_EQ(ref.maxBitrate, target.maxBitrate);
     EXPECT_EQ(ref.minBitrate, target.minBitrate);
     EXPECT_EQ(ref.maxFramerate, target.maxFramerate);
-    EXPECT_EQ(ref.VP8().complexity, target.VP8().complexity);
+    EXPECT_EQ(ref.GetVideoEncoderComplexity(),
+              target.GetVideoEncoderComplexity());
     EXPECT_EQ(ref.VP8().numberOfTemporalLayers,
               target.VP8().numberOfTemporalLayers);
     EXPECT_EQ(ref.VP8().denoisingOn, target.VP8().denoisingOn);
@@ -538,8 +539,8 @@ class TestSimulcastEncoderAdapterFake : public ::testing::Test,
     // stream 0, the lowest resolution stream.
     InitRefCodec(0, &ref_codec);
     ref_codec.qpMax = 45;
-    ref_codec.VP8()->complexity =
+    ref_codec.SetVideoEncoderComplexity(
-        webrtc::VideoCodecComplexity::kComplexityHigher;
+        webrtc::VideoCodecComplexity::kComplexityHigher);
     ref_codec.VP8()->denoisingOn = false;
     ref_codec.startBitrate = 100;  // Should equal to the target bitrate.
     VerifyCodec(ref_codec, 0);
@@ -1134,7 +1135,8 @@ TEST_F(TestSimulcastEncoderAdapterFake, DoesNotAlterMaxQpForScreenshare) {
   VideoCodec ref_codec;
   InitRefCodec(0, &ref_codec);
   ref_codec.qpMax = kHighMaxQp;
-  ref_codec.VP8()->complexity = webrtc::VideoCodecComplexity::kComplexityHigher;
+  ref_codec.SetVideoEncoderComplexity(
+      webrtc::VideoCodecComplexity::kComplexityHigher);
   ref_codec.VP8()->denoisingOn = false;
   ref_codec.startBitrate = 100;  // Should equal to the target bitrate.
   VerifyCodec(ref_codec, 0);
@@ -1167,7 +1169,8 @@ TEST_F(TestSimulcastEncoderAdapterFake,
   VideoCodec ref_codec;
   InitRefCodec(2, &ref_codec, true /* reverse_layer_order */);
   ref_codec.qpMax = kHighMaxQp;
-  ref_codec.VP8()->complexity = webrtc::VideoCodecComplexity::kComplexityHigher;
+  ref_codec.SetVideoEncoderComplexity(
+      webrtc::VideoCodecComplexity::kComplexityHigher);
   ref_codec.VP8()->denoisingOn = false;
   ref_codec.startBitrate = 100;  // Should equal to the target bitrate.
   VerifyCodec(ref_codec, 2);

modules/video_coding/codecs/test/videocodec_test_fixture_impl.cc

@@ -104,7 +104,6 @@ std::string CodecSpecificToString(const VideoCodec& codec) {
   rtc::SimpleStringBuilder ss(buf);
   switch (codec.codecType) {
     case kVideoCodecVP8:
-      ss << "complexity: " << static_cast<int>(codec.VP8().complexity);
       ss << "\nnum_temporal_layers: "
          << static_cast<int>(codec.VP8().numberOfTemporalLayers);
       ss << "\ndenoising: " << codec.VP8().denoisingOn;
@@ -113,7 +112,6 @@ std::string CodecSpecificToString(const VideoCodec& codec) {
       ss << "\nkey_frame_interval: " << codec.VP8().keyFrameInterval;
       break;
     case kVideoCodecVP9:
-      ss << "complexity: " << static_cast<int>(codec.VP9().complexity);
       ss << "\nnum_temporal_layers: "
          << static_cast<int>(codec.VP9().numberOfTemporalLayers);
       ss << "\nnum_spatial_layers: "
@@ -302,6 +300,8 @@ std::string VideoCodecTestFixtureImpl::Config::ToString() const {
   ss << "\nnum_simulcast_streams: "
      << static_cast<int>(codec_settings.numberOfSimulcastStreams);
   ss << "\n\n--> codec_settings." << codec_type;
+  ss << "complexity: "
+     << static_cast<int>(codec_settings.GetVideoEncoderComplexity());
   ss << "\n" << CodecSpecificToString(codec_settings);
   if (codec_settings.numberOfSimulcastStreams > 1) {
     for (int i = 0; i < codec_settings.numberOfSimulcastStreams; ++i) {

modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc

@@ -591,7 +591,7 @@ int LibvpxVp8Encoder::InitEncode(const VideoCodec* inst,
   }
 
   // Allow the user to set the complexity for the base stream.
-  switch (inst->VP8().complexity) {
+  switch (inst->GetVideoEncoderComplexity()) {
     case VideoCodecComplexity::kComplexityHigh:
       cpu_speed_[0] = -5;
       break;

modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc

@@ -76,7 +76,8 @@ class TestVp8Impl : public VideoCodecUnitTest {
     webrtc::test::CodecSettings(kVideoCodecVP8, codec_settings);
     codec_settings->width = kWidth;
     codec_settings->height = kHeight;
-    codec_settings->VP8()->complexity = VideoCodecComplexity::kComplexityNormal;
+    codec_settings->SetVideoEncoderComplexity(
+        VideoCodecComplexity::kComplexityNormal);
   }
 
   void EncodeAndWaitForFrame(const VideoFrame& input_frame,