H.264 video codec support using OpenH264/FFmpeg

webrtc/video/screenshare_loopback.cc

Index: webrtc/video/screenshare_loopback.cc
diff --git a/webrtc/video/screenshare_loopback.cc b/webrtc/video/screenshare_loopback.cc
index a221e9c52f14e44797b853ac2fa5b655b9a8f25a..6b1d6d421335bcda29e334a673ebbb1a735d1f5e 100644
--- a/webrtc/video/screenshare_loopback.cc
+++ b/webrtc/video/screenshare_loopback.cc
@@ -163,6 +163,9 @@ class ScreenshareLoopback : public test::Loopback {
     CHECK_LT(config.tl_discard_threshold, config.num_temporal_layers);
     CHECK_LT(config.sl_discard_threshold, config.num_spatial_layers);
 
+    h264_settings_ = VideoEncoder::GetDefaultH264Settings();
+    h264_settings_.frameDroppingOn = false;
+
     vp8_settings_ = VideoEncoder::GetDefaultVp8Settings();
     vp8_settings_.denoisingOn = false;
     vp8_settings_.frameDroppingOn = false;
@@ -186,7 +189,10 @@ class ScreenshareLoopback : public test::Loopback {
     encoder_config.content_type = VideoEncoderConfig::ContentType::kScreen;
     encoder_config.min_transmit_bitrate_bps = flags::MinTransmitBitrate();
     int num_temporal_layers;
-    if (config_.codec == "VP8") {
+    if (config_.codec == "H264") {
+      encoder_config.encoder_specific_settings = &h264_settings_;
+      num_temporal_layers = 1;
+    } else if (config_.codec == "VP8") {
       encoder_config.encoder_specific_settings = &vp8_settings_;
       num_temporal_layers = vp8_settings_.numberOfTemporalLayers;
     } else if (config_.codec == "VP9") {
@@ -234,6 +240,7 @@ class ScreenshareLoopback : public test::Loopback {
     return capturer;
   }
 
+  VideoCodecH264 h264_settings_;
   VideoCodecVP8 vp8_settings_;
   VideoCodecVP9 vp9_settings_;
 };