UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:53.0) Gecko/20100101 Firefox/53.0

Steps to reproduce the problem:
1. deploy the attached test.html
2. open the html file with chrome 58

What is the expected behavior?
play the 960 x 720 (4:3) video correctly.

What went wrong?
play 960 x 720 video with white bar in left side(wrong.png).
This should be correct.png.

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 58.0.3029.81  Channel: n/a
OS Version: OS X 10.12
Flash Version: Shockwave Flash 25.0 r0

It might be clone of this issue.

https://bugs.chromium.org/p/chromium/issues/detail?id=672603

This issue is Mac specific. No ploblem in windows.

Also recording the white bar video using mediaRecorder API results in correct video.

My web camera is here (Japanese).
This camera supports up to 1600x1200px.

http://www2.elecom.co.jp/multimedia/pc-camera/ucam-c0220fb/
 

Deleted: test.html 1.3 KB

test.html 1.3 KB View Download

Deleted: wrong.png 1.1 MB

	wrong.png 1.1 MB View Download

Deleted: correct.png 870 KB

	correct.png 870 KB View Download