First lines coming from OV5640 are all 0xAE

[bitslip]

Hello,

I'm working with the Zybo Pcam 5C (18.2) reference design.

While using the default resolution of 1920 * 1080 - I observe the AXI Stream but exiting from the GAMA CORRECTION IP (this is last core in the video chain before the VDMA).

A strange thing I noticed is that the first 4 lines at the beginning of each frame are a constant 0xAE for all pixels. ( all the red , green and blue pixels have the same value which is 0xAE ).

After the first 1920 * 4 pixels non - constant data starts to arrive.

Why is this ? Is this the way the sensor outputs data ?

[JColvin]

Hi @bitslip,

I suspect this is a gray line that is an artifact of the border interpolation algorithm that was used, detailed a little bit more here: https://reference.digilentinc.com/learn/programmable-logic/tutorials/zybo-z7-pcam-5c-demo/start#visible_border_line, since the color code AEAEAE matches the gray that is mentioned there. I'm not familiar with any further details beyond that, but can find out some more information if you would like.

Thanks,
JColvin