xine opengl video output and high cpu load

pinguin74 · 04-01-08, 03:41 AM

Hello!

I am using Xine (latest version 1.1.11.1) with the OpenGL video output. I have a GForce 6200 and use the 169.12 driver. OpenGL is properly installed.

When I play a video I get a relatively high CPU load, around 50% - 60% in average. I thought, that the driver would let the graphics card do much of the job? I just expected a much lower CPU load, cause I thought when you use the nVidia driver the card would do much of the math when playing a video... Is this assumption not true?

Thanx

**Thunderbird** · 04-01-08, 04:21 AM

Most likely the xine output plugin isn't very efficient. Sure opengl can do the scaling and things for 'free' but you need to get the data on the GPU. When you use traditional opengl calls texture uploads are being done synchronously. This can lead to high cpu usage because the cpu needs to wait before each upload is complete. If they would take advantage of asynchronous calls (using pixel buffer objects) the doesn't have to wait.

In other words OpenGL doesn't mean it is fast, it can be faster if the program is written in a good way.

pinguin74 · 04-02-08, 07:02 AM

Thanx for explaining. So, just using nVidia's drivers is not enough, it still depends on the application.

**Thunderbird** · 04-02-08, 11:29 AM

Correct. I think XVideo can be used asynchronously. In case of video when there is e.g. a cpu bottleneck it isn't bad when so now and then a frame is skipped if the movie continues playing. Most synchronous apps try to show each and every frame which is typically not what you want (if there is some resource limit).

04-01-08, 03:41 AM	#1
pinguin74 Registered User Join Date: Aug 2007 Posts: 36	xine opengl video output and high cpu load Hello! I am using Xine (latest version 1.1.11.1) with the OpenGL video output. I have a GForce 6200 and use the 169.12 driver. OpenGL is properly installed. When I play a video I get a relatively high CPU load, around 50% - 60% in average. I thought, that the driver would let the graphics card do much of the job? I just expected a much lower CPU load, cause I thought when you use the nVidia driver the card would do much of the math when playing a video... Is this assumption not true? Thanx

04-01-08, 04:21 AM	#2
Thunderbird Join Date: Jul 2002 Location: Netherlands, Europe Posts: 2,105	Re: xine opengl video output and high cpu load Most likely the xine output plugin isn't very efficient. Sure opengl can do the scaling and things for 'free' but you need to get the data on the GPU. When you use traditional opengl calls texture uploads are being done synchronously. This can lead to high cpu usage because the cpu needs to wait before each upload is complete. If they would take advantage of asynchronous calls (using pixel buffer objects) the doesn't have to wait. In other words OpenGL doesn't mean it is fast, it can be faster if the program is written in a good way.

04-02-08, 07:02 AM	#3
pinguin74 Registered User Join Date: Aug 2007 Posts: 36	Re: xine opengl video output and high cpu load Thanx for explaining. So, just using nVidia's drivers is not enough, it still depends on the application.

04-02-08, 11:29 AM	#4
Thunderbird Join Date: Jul 2002 Location: Netherlands, Europe Posts: 2,105	Re: xine opengl video output and high cpu load Correct. I think XVideo can be used asynchronously. In case of video when there is e.g. a cpu bottleneck it isn't bad when so now and then a frame is skipped if the movie continues playing. Most synchronous apps try to show each and every frame which is typically not what you want (if there is some resource limit).