DM816x Input capture for custom High Res

Thank you for your answer Brijesh,

Well it's too bad we can't allocate higher resolution... It's really important for me to maximize input resolution (even if color space is a bit degraded like 4:2:2).

Do you see any other hardware solution for me ? Perhaps another high frequency DSP component with other input capability ?

Many thanks again

What is the max resolution that you are targetting?

Regards,

Brijesh

Well,

Ideal input resolution would be 3000x3000, but we can handle other near-square ratio or a bit less in resolution.

Thanks again Brijesh

Few people have tried bigger resolution, see if it helps. you could get more information in below links.

http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/717/p/329652/1155831.aspx#1155831

http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/717/t/268906.aspx

Regards,

Brijesh

Many thanks Brijesh,

So it's possible based on : 165M/2 = 83Mpix/s max, isn't it ?

With a free ratio based on that maximum pix/s ?

If it's possible, it's not that bad... I understand too that a SN65LVDS324 can probably handle that video stream ?

What bit depth format could be possible for that custom input video stream ? Will YCbCr 4:2:2 and/or 4:2:0 be possible ? I didn't understood the scope of the limitations discussed in your second forum thread link...

Best regards

Hi,

If your input interface is something like bt1120, 165M pixels/sec. But you have BT656, then it is 165/2M Pixels/sec. If you are not using any of the vip pipeline internal modules like scalar/csc/chr_ds, it might be possible to get 4kx2k resolution. But this is not really validated fully. This is why i have said supported resolution is upto 1920x1080.

Rgds,

Brijesh

Hi Brijesh,

When you say "  If you are not using any of the vip pipeline internal modules..." :

Do you mean any of this function : p.262 : "Additional features include: programmable color space conversion, scaler and chroma downsampler, ancillary VANC and VBI data capture (decoded by software), noise reduction."

So we can't use the chroma downsampler, and data will be directly written in DDR as this, or is it limited to scaler ?

About the max 4k x 2k :

- How do you compute that max 8MPix value please ?

- Is it possible to set a free ratio based on that 8MPix limit ?

Thanks a lot for your patience !

Hi,

Yes, i meant we cannot use chroma down sample, scalar and CSC modules if resolution is more than 1920x1080 pixels.

So Maximum resolution is 4kx2k and maximum pixel clock supported is 165MHz, This is what maximum supported by video port.

I could not get the second question.

Rgds,

Brijesh

Hi Brijesh,

Is there any application note about that custom video port configuration ?

My second question was more an ask for confirmation : @30fps : 4Kx2K = 2828x2828 = 8 MPix.

So, in theory, a 2828x2828 resolution is possible too, isn't it ?

Thanks again

Hi,

Here 4Kx2K mean 4096x2048. This is stil active video resolution. You will need to include horizontal and vertical blanking into it, then you consider 165MHz pixel clock, you could get the fps.

Rgds,

Brijesh

Hi Brijesh,

Many thanks again. As you understood, we are studying feasibility at this point.

As soon as we will know what minimum Hsync and Vsync time are recommended for DM816x, we'll get the answer for feasibility.

I'm looking for this values in many different datasheets and application notes. I understood there is a minimum number of lines to determine minimum Vsync, but I can't find the good values (same for Hsync).

I hope I will find it !

Best regards

Hi,

It should be documented in hdvpss TRM.

Regards,

Brijesh