1132994 - Playback of H.264 on Mac drops many frames on slower system

Status: RESOLVED WORKSFORME

(Core :: Audio/Video, defect)

Description

[Marijn de Jong]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:35.0) Gecko/20100101 Firefox/35.0
Build ID: 20150122214805

Steps to reproduce:


One clear example can be seen at https://bundles.bittorrent.com/bundles/hitspwyw which calls an .mp4 file.


Actual results:

The video plays fine in Safari, in Firefox the audio is fine yet the video is a slide show.


Expected results:

With my underpowered CPU (Core2Duo) I suspect Firefox is not using any hardware accelleration while Safari is. 

System summary: Mac mini (2009), Core2Duo 2,53GHz, 4GB, SSD, OSX 10.10 Yosemite.

Comment 1

[Jean-Yves Avenard [:jya]]

Can you try with beta 36 if you see any improvement?
Can you please try setting the preference media.apple.forcevda to true?

With or without the pref.

After changing the preference, you must restart Firefox for it take effect.

VDA on those Mac mini only allows up to 4 videos to be hardware accelerated at a time, and if you're running OS X 10.7 or 10.6, be prepare for the kernel to crash with some videos. should be running 10.8

Comment 2

[Marijn de Jong]

(In reply to Jean-Yves Avenard [:jya] from comment #1)
> Can you try with beta 36 if you see any improvement?
> Can you please try setting the preference media.apple.forcevda to true?
> 
> With or without the pref.
> 
> After changing the preference, you must restart Firefox for it take effect.
> 
> VDA on those Mac mini only allows up to 4 videos to be hardware accelerated
> at a time, and if you're running OS X 10.7 or 10.6, be prepare for the
> kernel to crash with some videos. should be running 10.8

Plays fine in Firefox 36 beta. I can't find the preference in about:config though, I only have media.apple.mp3 and media.apple.mp4.

Good to know this seems to be fixed in FF36!

Comment 3

[Jean-Yves Avenard [:jya]]

You need to create the preference for VDA