980266 - [META] Improve the performance of B2G::WebRTC video encoding path

Status: RESOLVED WONTFIX

(Core :: WebRTC: Audio/Video, defect)

Description

[u459114]

This is a follow up bug of Bug 970183.

With the change in bug 970183, we always rotate source images, came from camera, at MediaEngineWebRTCVideoSource::OnNewPreviewFrame.

It introduces two side effects
1. Since we changed graphic buffer into normal YCrCB image, we need to image uploading at compositor side. Before the change, upload texture is not needed since we use direct texture.
2. We introduce one more image copy in MediaEngineWebRTCVideoSource

To recover this performance downgrade, instead of rotating image at the upstream of media pipeline, we do the rotation in later stage:
1. (Preview path) Rotate image in layer. The performance impact in compositor side of image rotation is pretty minor.
2. (Encode path) Rotate image at
http://dxr.mozilla.org/mozilla-central/source/media/webrtc/trunk/webrtc/common_video/i420_video_frame.cc#61

Comment 1

[Peter Chang[:pchang]]

Unassigned because this is meta bug

Comment 2

[Sylvestre Ledru [:Sylvestre]]

Mass closing as we are no longer working on b2g/firefox os.

Comment 3

[Sylvestre Ledru [:Sylvestre]]

Mass closing as we are no longer working on b2g/firefox os.