[SOLVED] VLC - vdpau-video - intermittant behavior

bt · 2010-07-20 13:27:18

Per the instructions with the upgrade to vlc, I installed vdpau-video. There are two boxes in vlc preferences:
1. in the Video section - Accelerated video output(Overlay), and
2. In Input & Codecs section - Use GPU Acceleration (experimental)

Checking the box in Input & Codecs section freezes the output.
Checking the box in the Video Section has two results - either it works or it doesn't. When it works the cpu usage is about 15 percent. When it doesn't work cpu usage hovers around 60 percent.
Checking both boxes does not change the above behavior.

I do have a dual-core cpu so the problem is not critical, but I it seems that the video output is a little smoother when the accelerated video is working.

As a check I opened mplayer (after putting channels.conf in ~/.mplayer) with the following command -- and it works perfectly:

mplayer -really-quiet -vo vdpau -ao alsa:device=spdif -ac hwac3 dvb://WCBS-HD

Any suggestions on why vlc is experiencing intermittant behavior?

EDIT: The partial solution came by going to lines 93-94 in ~/.config/vlcrc and removing the comment from the line after Hardware decoding so that it reads: ffmpeg-hw=0.
Next in the Video section of the preferences box under Tools check the box that reads "hardware acceleration(Overlay).
Next in the Input & Codecs section make sure that you uncheck GPU hardware acceleration.

I have no idea why this works, but it does on most of the hdtv stations that I receive -- but not all of them.

Last edited by bt (2010-07-21 18:42:39)

wonder · 2010-07-20 13:36:20

your way of using vdpau with mplayer is faulty. you need to pass -vc to actually work

but i've seen that vlc has cpu usage even the GPU Acceleration is used. i think is because vdpau-video is limited and buggy

bt · 2010-07-20 13:47:17

Thanks for the information. I will try with -vc -- but -- it works perfectly as written.

EDIT - upon running: mplayer -vo help I find that vdpau is listed as one of the video output drivers

Last edited by bt (2010-07-20 13:50:01)

wonder · 2010-07-20 15:05:33

mplayer -vo vdpau -vc ffh264vdpau,ffmpeg12vdpau,ffvc1vdpau,ffwmv3vdpau, file

Gusar · 2010-07-20 17:20:33

wonder wrote:

but i've seen that vlc has cpu usage even the GPU Acceleration is used. i think is because vdpau-video is limited and buggy

It's because VLC always copies the decoded frames back into system memory, while mplayer displays them directly. The advantage of copying frames back is that you can manipulate them using software filters, the disadvantage is copying takes CPU resources.

bt · 2010-07-20 19:45:40

Wonder --

Many thanks for the clarification.

Arch Linux

#1 2010-07-20 13:27:18

[SOLVED] VLC - vdpau-video - intermittant behavior

#2 2010-07-20 13:36:20

Re: [SOLVED] VLC - vdpau-video - intermittant behavior

#3 2010-07-20 13:47:17

Re: [SOLVED] VLC - vdpau-video - intermittant behavior

#4 2010-07-20 15:05:33

Re: [SOLVED] VLC - vdpau-video - intermittant behavior

#5 2010-07-20 17:20:33

Re: [SOLVED] VLC - vdpau-video - intermittant behavior

#6 2010-07-20 19:45:40

Re: [SOLVED] VLC - vdpau-video - intermittant behavior

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