New issue
Advanced search Search tips

Issue 672728 link

Starred by 2 users

Issue metadata

Status: WontFix
Owner:
Closed: Jan 2017
Cc:
Components:
EstimatedDays: ----
NextAction: ----
OS: ----
Pri: 2
Type: Bug



Sign in to add a comment

WebRTC screen sharing artefacts

Reported by serejkas...@gmail.com, Dec 9 2016

Issue description

<b>Chrome Version       : <Copy from: 'about:version'></b>
URLs (if applicable) : 
Other browsers tested:
  Add OK or FAIL, along with the version, after other browsers where you
have tested this issue:
     Safari: Doesn't support WebRTC
    Firefox: Reproducible
         IE: Doesn't support WebRTC

What steps will reproduce the problem?
(1) Install app https://chrome.google.com/webstore/detail/desktop-capture-sample/mhkidniocjdaiddjckopkigjmjbadfji
(2) Share application (Windows Explorer, Skype)
(3) Move other applications over one which shared.

What is the expected result?
Shared application should display correctly.

What happens instead?
There are artifacts on shared application.

Please provide any additional information below. Attach a screenshot if
possible.

Prerequisite: Windows 7 with Basic theme.

 
2016-12-08_16-41-29.png
266 KB View Download
Components: Blink>WebRTC
Cc: braveyao@chromium.org
Owner: qiangchen@chromium.org
qiangchen@ can you triage?

Comment 3 by mcasas@chromium.org, Dec 12 2016

Components: -Blink>WebRTC Blink>GetUserMedia>Desktop
Labels: -Pri-3 Pri-2
Status: Started (was: Unconfirmed)
I just reproduced the issue. 
The window share works fine with Aero Themes, but not with Basic Themes.

It looks a little weird, as the original window does not render correctly.
I think it is a bug of windows API PrintWindow [1].

We have two ways to do window capture:
1. PrintWindow
2. BitBlt

The difference is that 
BitBlt is faster, but on Basic theme, it would capture other windows that are covering the sharing target. (On Aero theme, it works fine.)

PrintWindow is slower, and on Basic theme, it would cause this bug, if you drag other windows over the sharing target.

Probably we do not have a way to fix it.

[1]https://cs.chromium.org/chromium/src/third_party/webrtc/modules/desktop_capture/window_capturer_win.cc?q=windowcapturerw&sq=package:chromium&l=233


Status: WontFix (was: Started)
As this is a bug of windows.

Sign in to add a comment