[beagleboard] ITU-R BT 656 compatible camera interface

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1

Dear all,

I would like to interface a ITU-R BT 656 compatible camera to the beagleboard XM camera interface. I did a check of the TRM and I get the impression that it is very well possible to make this interface work. The Camera image signal Processor is supporting this.
And I found a different omap3 board which uses a television encoder chip on this interface http://labs.igep.es/index.php/How_to_setup_tvp5151_video_decoder.

From this webpage I understand that there is an omap3-isp kernel driver which should support this already and is available for a couple of kernels (http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/29082).

And I understand that I will need a program media-ctl to control this interface to setup the processing pipeline.

Has someone experience with this interface?
I could not find much documentation, is there some wiki / blog with some explanations how this works and should be activated on the beagleboard. Has someone a pointer on how to use this?
And does this work (easily) with Angstrom?

(I have seen some discussions between Laurent Pinchart and Thomas Gary on this subject on the linux-media list. Maybe I should just ask there as well.)

Greetings,

Han

2

Hi,

The BT656 interface is already supported and working on top of OMAP3ISP via video decoder chip TVP5146.
If you are using upstream kernel then I would recommend you to refer to the patch-series submitted recently on linux-media -

http://www.mail-archive.com/linux-media@vger.kernel.org/msg36679.html

You only need changes done if ISP code for supporting BT656 interface, and respective board hook up changes in board file along with sensor driver.

As far as usage is concerned, yes, you need media-ctl (or any application) to setup the link before starting streaming.

Thanks,
Vaibhav

3

Hi,

The BT656 interface is already supported and working on top of OMAP3ISP via video decoder chip TVP5146.
If you are using upstream kernel then I would recommend you to refer to the patch-series submitted recently on linux-media -

http://www.mail-archive.com/linux-media@vger.kernel.org/msg36679.html

Which kernel do you advice to use in combination with this patch set?
Angstrom is normally using 2.6.32 for the beagleboard.
But I assume that I can better try my luck with a 3.0.x or 3.1.0 mainline kernel. I assume that all of the specific beagleboard XM (ver B) items are already in.

You only need changes done if ISP code for supporting BT656 interface, and respective board hook up changes in board file along with sensor driver.

Thanks for the advice.

As far as usage is concerned, yes, you need media-ctl (or any application) to setup the link before starting streaming.

Which repository do you advice me to use for media-ctl?
It works very close with the API defined in the kernel so I assume that I cannot pull in “any” version from Angstrom or where ever.
I assume that I can best use this: http://git.ideasonboard.org/?p=media-ctl.git;a=summary

Thanks,
Vaibhav

Thanks,
Han

4

Hi there,

I just would like to share my experience on enabling BT.656 support in BBxM where Kernel 3.7.13 (stable-kernel) is in use. The changes made were inside of omap3isp and board-omap3beagle. Basically bridge and bt656 parameters were missing. The parallel bridge needs to be disable to collect YCbCr8 input data. In order to do these configuration in ccdc_config_sync_if() and ccdc_configure() functions, you can check out the latest version of “ispccdc.c” in TI Kernel distribution.

Regards,
Ozkan.