Android: enable/disable WebRTC HW H264 with a flag.

content/renderer/media/gpu/rtc_video_encoder_factory.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/gpu/rtc_video_encoder_factory.h"
 
 #include "base/command_line.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/feature_h264_with_openh264_ffmpeg.h"
 #include "content/renderer/media/gpu/rtc_video_encoder.h"
 #include "media/gpu/ipc/client/gpu_video_encode_accelerator_host.h"
 #include "media/renderers/gpu_video_accelerator_factories.h"
 #include "media/video/video_encode_accelerator.h"
 
 namespace content {
 
 namespace {
+bool IsCodecDisabledByCommanLine(std::string codec_name) {
+  const base::CommandLine* cmd_line = base::CommandLine::ForCurrentProcess();

[DaleCurtis, 2016/09/29 00:31:36]

Pass in?

[braveyao, 2016/09/29 19:26:26]

Done.

+  bool result = true;
+  if (!cmd_line->HasSwitch(switches::kDisableWebRtcHWEncoding) ||

[DaleCurtis, 2016/09/29 00:31:35]

early return. store getswithvalueascii for comparison.

[braveyao, 2016/09/29 19:26:26]

Done.

+      (!cmd_line->GetSwitchValueASCII(switches::kDisableWebRtcHWEncoding)
+            .empty() &&
+       cmd_line->GetSwitchValueASCII(switches::kDisableWebRtcHWEncoding) !=
+           codec_name)) {
+    result = false;
+  }
+  return result;
+}
 
 // Translate from media::VideoEncodeAccelerator::SupportedProfile to
 // one or more instances of cricket::WebRtcVideoEncoderFactory::VideoCodec
 void VEAToWebRTCCodecs(
     std::vector<cricket::WebRtcVideoEncoderFactory::VideoCodec>* codecs,
     const media::VideoEncodeAccelerator::SupportedProfile& profile) {
   const int width = profile.max_resolution.width();
   const int height = profile.max_resolution.height();
   const int fps = profile.max_framerate_numerator;
   DCHECK_EQ(profile.max_framerate_denominator, 1U);
 
   const base::CommandLine* cmd_line = base::CommandLine::ForCurrentProcess();
   if (profile.profile >= media::VP8PROFILE_MIN &&
       profile.profile <= media::VP8PROFILE_MAX) {
-    codecs->push_back(cricket::WebRtcVideoEncoderFactory::VideoCodec(
-        webrtc::kVideoCodecVP8, "VP8", width, height, fps));
+    if (!IsCodecDisabledByCommanLine(switches::kDisableWebRtcHWEncodingVPx)) {

[DaleCurtis, 2016/09/29 00:31:35]

CommandLine.

[braveyao, 2016/09/29 19:26:26]

Done.

+      codecs->push_back(cricket::WebRtcVideoEncoderFactory::VideoCodec(
+          webrtc::kVideoCodecVP8, "VP8", width, height, fps));
+    }
   } else if (profile.profile >= media::H264PROFILE_MIN &&
              profile.profile <= media::H264PROFILE_MAX) {
     // Enable H264 HW encode for WebRTC when SW fallback is available, which is
     // checked by kWebRtcH264WithOpenH264FFmpeg flag. This check should be
     // removed when SW implementation is fully enabled.
     // kEnableWebRtcHWH264Encoding flag is only enabled for extensions, and
     // can be used without SW fallback.
     bool webrtc_h264_sw_enabled = false;
 #if BUILDFLAG(RTC_USE_H264) && !defined(MEDIA_DISABLE_FFMPEG)
     webrtc_h264_sw_enabled =
         base::FeatureList::IsEnabled(kWebRtcH264WithOpenH264FFmpeg);
 #endif  // BUILDFLAG(RTC_USE_H264) && !defined(MEDIA_DISABLE_FFMPEG)
     if (cmd_line->HasSwitch(switches::kEnableWebRtcHWH264Encoding) ||

[DaleCurtis, 2016/09/29 00:31:36]

Can this flag be deleted now?

[braveyao, 2016/09/29 19:26:26]

No. This is for extension on Mac. please see the comments above.

[DaleCurtis, 2016/09/29 19:34:14]

How is that flag passed? Can you remove that flag and specify
--disable-...-=h264 on all platforms except mac?

[braveyao, 2016/09/30 18:22:02]

You are right. I'll discuss with other and follow it up in a separate cl.

-        webrtc_h264_sw_enabled) {
+        webrtc_h264_sw_enabled ||
+        !IsCodecDisabledByCommanLine(switches::kDisableWebRtcHWEncodingH264)) {
       codecs->push_back(cricket::WebRtcVideoEncoderFactory::VideoCodec(
           webrtc::kVideoCodecH264, "H264", width, height, fps));
     }
   }
 }
 
 }  // anonymous namespace
 
 RTCVideoEncoderFactory::RTCVideoEncoderFactory(
     media::GpuVideoAcceleratorFactories* gpu_factories)
@@ skipping 19 matching lines @@
 RTCVideoEncoderFactory::codecs() const {
   return codecs_;
 }
 
 void RTCVideoEncoderFactory::DestroyVideoEncoder(
     webrtc::VideoEncoder* encoder) {
   delete encoder;
 }
 
 }  // namespace content