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Is VLC multithreaded?

Posted: 12 Mar 2007 04:48
by Snowrunner
Out of curiosity after doing some benchmarking on my dual G5, is VLC multithreaded? It seems to me it's not?

Posted: 12 Mar 2007 10:02
by Jean-Baptiste Kempf
This question does not mean anything...

VLC is multithreaded but many codecs are not...

Posted: 12 Mar 2007 10:14
by Snowrunner
This question does not mean anything...

VLC is multithreaded but many codecs are not...
Okay,

let me be more precise ;)

I am trying to play back x.264 encoded content in a Matroska container and it seems to me it is not multi-threaded?

I am asking this because I have severe frame dropping on my Dual PowerMac G5 2.4GHz. Looking at the System Monitor it seems to me that the process is taking up to 90% CPU and still dropping frame, so I am assuming the codec is not multithreaded?

Posted: 12 Mar 2007 11:02
by Jean-Baptiste Kempf
Exactly. FFMPEG H.264 decoder is NOT multi-threaded and with HD-TV, this makes many frames drops... Sorry you can not do anything about it...

Posted: 12 Mar 2007 16:44
by Snowrunner
Exactly. FFMPEG H.264 decoder is NOT multi-threaded and with HD-TV, this makes many frames drops... Sorry you can not do anything about it...
Damn :(

So next question, I was thinking about getting a "TV Dedicated" Mac Mini, would it have enough horsepower to play back 720p content on one core with VLC?

Posted: 12 Mar 2007 22:28
by The DJ
My iMac Core2Duo 2Ghz can playback H264 1080p with VLC. That's all i can say about it.

Posted: 12 Mar 2007 22:33
by Snowrunner
My iMac Core2Duo 2Ghz can playback H264 1080p with VLC. That's all i can say about it.

Okay thanks.

I guess I just grab the latest VLC build and try it out at the store and see how it performs.

Any recommendation on Memory for the Mac? Does more memory help with playback or is the DVD drive / HDD fast enough and memory caching is not an issue?

*Update*

I bit the bullet and bought a MacMini yesterday and it will in all likeyhood go back to the store on the weekend. The problem I am running into is that 720p content works fine and looks great, but 1080p, x264 content is jerky / doesn't work as hoped for.

Bummer really, I like the little box already, I guess I have to wait until FFMPEG either goes Multithreaded or Apple throws out a faster CPU in the Mini (2GHz looks like the "sweet" spot).

Thanks for all the feedback guys.

Posted: 19 Mar 2007 11:58
by Playermaniac
This subjet exist too in French! Look at this --> viewtopic.php?t=26633

Posted: 19 Mar 2007 17:12
by bnz
Yes, i am experiencing the same with my macbook. I cannot play 1080i h264 content without stutter. I really hope the ffmpeg guys will optimize the h264 decoder soon. The CoreAVC guys are working on a Macintosh version, but i doubt that this will somehow work with VLC or mplayer and i need a splitter for .ts files.

Posted: 20 Mar 2007 18:41
by Snowrunner
Yes, i am experiencing the same with my macbook. I cannot play 1080i h264 content without stutter. I really hope the ffmpeg guys will optimize the h264 decoder soon. The CoreAVC guys are working on a Macintosh version, but i doubt that this will somehow work with VLC or mplayer and i need a splitter for .ts files.
Actually here is a funny observation. When I was playing back content I saw the CPU go up to 120%, which seems to indicated that on the MacTel it IS multithreaded.

Still, doesn't work as hoped for, so the MacMini now is back and I'll try again when the next version is out.

Posted: 25 May 2007 17:58
by pjwhite
Snowrunner, you have to note that the 120% is total usage. So you must be sure that VLC itself may not go over 100% and if it is, it's likely that the display or demuxing part of it are operating on different threads (as people mentioned here). The problem is when you have 1080p being decoded in one thread.

Posted: 25 May 2007 18:10
by Snowrunner
Snowrunner, you have to note that the 120% is total usage. So you must be sure that VLC itself may not go over 100% and if it is, it's likely that the display or demuxing part of it are operating on different threads (as people mentioned here). The problem is when you have 1080p being decoded in one thread.
The 120% showed for the process, not overall CPU usage, obviously there were some other things running.

Doesn't matter that much anymore really, as with the latest XBOX update my playback options have vastly improved, my bigger problem right now is that I have to re-encode the video to play back on the XBOX and that takes ~5 hours for every hour of video. I really think I need an upgrade :)

Posted: 25 May 2007 18:19
by Jean-Baptiste Kempf
Some people are trying to improve multi-threading in FFMPEG h264 decoder.

Posted: 25 May 2007 18:20
by Snowrunner
Some people are trying to improve multi-threading in FFMPEG h264 decoder.
I am still hoping :) Sometimes I wish I could be a programmer :)

Posted: 27 May 2007 15:01
by Ryoken
God I hope so.. Not being able to play 1080p x264 MKV files on my Intel iMac Core Duo 2Ghz is what made me just start building a new HTPC .. It doesn't need to be much better.. I only need another ~15% of CPU power to one of my cores and all would be fine, or good multithreading to spead it evenly..

Though with it all being based on FFMPEG, why does FFDShows x264 seem better on dual core CPU's ? Shoudn't we be on par ?