Problem in V4L2 Capture on DM-816x

ramakrishna deshpande

Other Parts Discussed in Thread: TVP7002, SYSBIOS

Hi,

I have doubt on DM-816x(Netra) V4L2 capture device.

What will be the out put of TVP 7002 decoder(capture format) is it YUV422(YCbYCr 8-bit)..?

We are using dm816x_hdvpss_v4l2.xem3 and inserting ti81xxvin.ko and ti81xxvo.ko,

I want to set YUV422(YCbYCr 8-bit), please tell me how to configure this(Any settings if require in drivers or HDVPSS xem3)

Where can I get the more details on the same.

With Regards,

Ramakrishna Deshpande.

over 12 years ago

0 Renjith Thomas over 12 years ago

Guru 31670 points

This link might help you out.

http://processors.wiki.ti.com/index.php/DM81xx_AM38xx_Adding_External_Decoders_to_V4L2_Capture_Driver

0 HardikShah over 12 years ago in reply to Renjith Thomas

TI__Mastermind 20245 points

Hi,

It is possible to configure the capture hardware based on how your decoder is connected to capture. TVP7002 is giving out BT1120, that is 16-bit. you need to re-configure the capture driver to take 8-bit using the above app note. People have brought up 8-bit capture using above app note.

0 Sudeep Hegde over 12 years ago in reply to HardikShah

Intellectual 660 points

Hi Hardik,

Thanks for the inputs, do let me know if i can do omx calls for V4l2 capture?..

Regards,

Sudeep

0 HardikShah over 12 years ago in reply to Sudeep Hegde

TI__Mastermind 20245 points

No,

You cant do omx calls for V4L2 capture. OMX calls VPSS-M3 captured driver instead of Linux V4L2 capture driver.

0 Sudeep Hegde over 12 years ago in reply to HardikShah

Intellectual 660 points

Hi Hardik,

Thanks indeed for quick reply, I want one more clarification.

Is it possible to develop OMX interfaces for V4L2 drivers from VFCC side, are there any dependencies on it.

Regards,

Sudeep

0 David Hill100919 over 12 years ago in reply to Sudeep Hegde

Intellectual 310 points

Hi, Sudeep,

I have the same problem as you.

Regards,

Jiaxin Peng.

0 HardikShah over 12 years ago in reply to David Hill100919

TI__Mastermind 20245 points

Hi,

OMX is just a framework and it can be developed on any drivers level framework. So technically this should be feasible.

0 Krunal Patil over 12 years ago in reply to HardikShah

Genius 3120 points

Hi Guys,

Sorry for jumping into the discussion but I found it interesting.

As Hardik said, technically one can have OMX wrapper on top of V4L2.

@Sudeep, Can you please describe what is the purpose behind doing so?

Regards,

Krunal

0 Sudeep Hegde over 12 years ago in reply to Krunal Patil

Intellectual 660 points

@Hardik: Thanks for the valuable inputs.

Hello Krunal,

The V4l2 drivers have the ioctl interfaces, means it should run on A8 side.

But A8 is typically used for running applications, so that the load can be offloaded to VFCC component which captures the data through V4l2 drivers.

I have one doubt here, as to whether V4L2 drives can be interfaced with sysbios on VFCC M3..?

Regards,

Sudeep

0 Krunal Patil over 12 years ago in reply to Sudeep Hegde

Genius 3120 points

Hi Sudeep,

I am less hopeful of having V4L2 driver in sysbios. Never heard of having this support in sysbios.

TI experts?

Regards,

Krunal

0 HardikShah over 12 years ago in reply to Krunal Patil

TI__Mastermind 20245 points

Sysbios has its own framework for capturing Video that is VFCC and FVID2 drivers. Why you want V4L2 there. If you want to offload it to M3 than please use VFCC instead of porting V4L2 on sysbios. You cant get all interfaces on all processors.

0 Sudeep Hegde over 12 years ago in reply to HardikShah

Intellectual 660 points

Hi Hardik/Krunal,

Sorry for the confusion, Here i mean to say that the captured frame should be available through VFCC component (FVID2).

Other initialization should happen on the A8 side for V4L2.

regards,

Sudeep

0 HardikShah over 12 years ago in reply to Sudeep Hegde

TI__Mastermind 20245 points

V4L2 is implemented that way only, its a wrapper for V4L2 interfaces, finally everything is done on VPSS-M3 only.

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Problem in V4L2 Capture on DM-816x