Danara
Posts: 13
Joined: Mon Dec 31, 2012 8:12 pm
Location: Ottawa Canada

Video_splitter component

Sat Apr 20, 2013 10:52 pm

I am quite intrigued by the video_splitter OMX component. Has anybody been able to make this work? I have been unable to locate much of anything in the way of example code for any platform, let alone the RPi. Anybody used this component yet?

dickon
Posts: 482
Joined: Sun Dec 09, 2012 3:54 pm
Location: Home, just outside Reading

Re: Video_splitter component

Sun Apr 21, 2013 8:04 am

Yeah. omxtx can use it when in 'monitor' mode (which basically dumps the output of the decoder into the splitter, and one of its outputs into the renderer). Did it as a bit of fun over christmas.

Danara
Posts: 13
Joined: Mon Dec 31, 2012 8:12 pm
Location: Ottawa Canada

Re: Video_splitter component

Sun Apr 21, 2013 3:05 pm

It would be nice if we could "fill-out" examples for all the omx components, like the existing ones under Hello_pi. It is much easier to learn how to use them when you have a working example to start with.
Video splitter is one, but there are others I would like to see as well.

dickon
Posts: 482
Joined: Sun Dec 09, 2012 3:54 pm
Location: Home, just outside Reading

Re: Video_splitter component

Sun Apr 21, 2013 3:54 pm

TBH, they're all pretty similar: obtain handle, set ports to Disabled, allocate buffers / sort out tunnels, set ports to Enabled, transition to Executing, feed data / collect data as appropriate.

Really, you just need to read and understand the OpenMAX specification, and the hello_pi/* examples and the likes of the omxplayer source code should help with that. omxtx's monitor mode took me about two hours to implement, once I decided to look into how to do it; I think the resizer was similar (there's only one extra component to worry about with that rather than two), and the deinterlacer similar (because I restructured the tunnelling setup to make it easier to bolt components in and out).

Danara
Posts: 13
Joined: Mon Dec 31, 2012 8:12 pm
Location: Ottawa Canada

Re: Video_splitter component

Sun Apr 21, 2013 4:20 pm

I've done a lot of that too, but the learning curve for people not familiar with it is pretty steep. The hello_pi examples are very useful for people learning to program on this platform -- I just think it would be helpful if there were more working simple examples covering some of the other components, like the splitter.

dickon
Posts: 482
Joined: Sun Dec 09, 2012 3:54 pm
Location: Home, just outside Reading

Re: Video_splitter component

Sun Apr 21, 2013 6:40 pm

Personally, I think that by the time you're ready to use the splitter -- fairly advanced usage, by any stretch -- you should be fairly clear about what you need to do to drive it.

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