HD YUV422 8 bit 2 way pixel multiplexed stream mode for video capture

Jenson Chin

Prodigy 60 points

Dear supporter,

My DVR system has a customized application for HDVPSS of DM8168. that is

The video stream is sourced from a FPGA logic.

I want to transmit 2 ch 1920*1080i 30fps on a single 8 bit video port with BT656 format.

The clock for each ch is 74.25 Mhz such that the multiplexed stream has a clock rate of 148.5 Mhz.

The mode of multiplexed stream is YUV422 8 bit 2x pixel multiplexed with BT.656 embedded sync.

I tried some VPSS code modification but it doesn't work. VPSS can not get anything and I don't see any error message.

Besides, to verify the other environment is 'good', I did a test:

I change the capture mode to 8 bit single channel embedded sync mode to receive 1080p 30fps (148.5Mhz). Of course ,the FPGA logic is also changed.

VPSS can get correct video data!

So, it seems everything is OK except the multiplex video stream format is used or not.

Does anyone can give me help?

Thanks!

over 13 years ago

0 Badri Narayanan over 13 years ago

TI__Guru 59700 points

I dont think this is possible. Below is information from HDVPSS user guide:

VIP Input Data Features
• 8 bit input ports
    • A single non-multiplexed CIF/480i/480p/720p/1080i Y/C data
    • Up to 2-stream multiplexed ED (480p) Y/C data
    • Up to 4-stream multiplexed SD (480i) Y/C data
    • Up to 16-stream multiplexed CIF Y/C data (TBD – 16)
• 16/24 bit input ports
    • A single non-multiplexed CIF/480i/480p/720p/1080i/1080p Y/C data
    • A single 24-bit YCbCr component or raw RGB data
    • Up to 2-stream multiplexed HD (720p/1080i) Y/C data

So for capturing 2ch 1920*1080i you will have to use 16/24 bit video port.

0 Jenson Chin over 13 years ago in reply to Badri Narayanan

Prodigy 60 points

Dear Badri,

Nice to see you reply so quickly and thanks for your patient to understand my question.

I can not understand why DM8168 has this restriction?

I mean that the clock speed of my 2 ch multiplexed video stream doesn't over the limitation of DM8168 VIP which is 165Mhz.

I really have no idea why DM8168 is not able to receive this kind of video stream?

I guess maybe there are some kind of special reasons in hardware, maybe not.

If it's possible and It would be nice if you can tell me a bit detail about it.

Thank you very much and Looking forward to your reply.

0 Chris Lee2 over 13 years ago in reply to Jenson Chin

Prodigy 40 points

I am interested in this, too.

I agree that the limitation should only apply to the max clock rate of 165M.

And I hope there will be an update to break the picture size restriction.

0 Brijesh Jadav over 13 years ago in reply to Chris Lee2

TI__Guru**** 482145 points

Hi,

Which mux mode you are using for 2ch 1080i? Is it the line mux mode or pixel mux mode?

Thanks,

Brijesh Jadav

0 Chris Lee2 over 13 years ago in reply to Brijesh Jadav

Prodigy 40 points

as shown in the thread's title and the first initial post, it's 8-bit 2 way pixel multiplexed stream.

0 Brijesh Jadav over 13 years ago in reply to Chris Lee2

TI__Guru**** 482145 points

Hi,

In pixel mux mode, channel id could be at one of the two places i.e. either embedded in four protection bits inside SAV/EAV or in the horizontal blanking pixel data. Could you check this and configure port accoridngly?

Regards,

Brijesh Jadav

0 Chris Lee2 over 13 years ago in reply to Brijesh Jadav

Prodigy 40 points

thanks for the information.

I didn't insert channel id, I will try it out.

0 Brijesh Jadav over 13 years ago in reply to Chris Lee2

TI__Guru**** 482145 points

Hi,

Without channel id, port will not put content in the correct channel and we will be waiting for the content on the correct channel.

Regards,

Brijesh Jadav

0 Chris Lee2 over 13 years ago in reply to Brijesh Jadav

Prodigy 40 points

I am glad to see this discussion has came out a good result.

Thanks for the prompt help.

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HD YUV422 8 bit 2 way pixel multiplexed stream mode for video capture