Zybo z7-20 hdmi demo problems

[ojava2018@agruni.edu.ge]

I have problems with HDMI demo on ZYBO Z7-20, The demo runs well but the resolutions are not correct its kind of crops the stream, the other problem is that on photos and videos red lines appear on edges of the objects and gradients, this happens on videos and photos and not on text, for example if I watch a youtube most of corners of objects get this red lines and other texts for example video description looks normal

[JColvin]

Hi @ojava2018@agruni.edu.ge,

I'm not sure what you mean by cropping the stream; you mean that if you select a matching resolution output to what the Zybo Z7 detects your monitor to be that it does not properly fill the display?

I don't recall seeing red lines appear on the edges of different supplied images; the demo is not configured to have any sort of algorithm that detects the different types of supplied video data. What version of Vivado are you testing the HDMI demo on so I can see if I can replicate this?

Thanks,
JColvin

[ojava2018@agruni.edu.ge]

@JColvin Thanks for replay, I'm using vivado 2018.2,  i set my display resolution to 1280x720 on my laptop and duplicated the screen then set the same resolution on zybo and image is cropped, on function 8  it grubs full frame, strange red lines which appear on videos and photos seemed to be caused by axi stream subset converter where colors are swapped, i removed them and its now correct, i dont know why this color swapping is necessary there, other problem i have is that when i duplicate my screen it works but if i extend my screen then it cant detect hdmi anymore. 

 

Edited June 25, 2021 by ojava2018@agruni.edu.ge

[JColvin]

Hi @ojava2018@agruni.edu.ge,

I pulled up an already built 2018.2 Zybo Z7-20 HDMI demo that I had labeled as a release project from Github and can confirm that there are some red lines on static images; I can also see them on dynamic images as well. I've reached out to another engineer who usually updates and maintains the HDMI projects about this and your detail about the color swapping.

I wasn't quite able to replicate the error where HDMI is not detected anymore though. When I switch between duplicating and extending the displays, there is a few seconds where the Zybo Z7 (as per the Tera term output) reports that the HDMI is unplugged, but it then successfully refreshes and displays the desktop again.

Thanks,
JColvin

[ojava2018@agruni.edu.ge]

@JColvin yes this red lines appeared on static images too, the detection problem is not consistent, I'm not really sure when it happens sometimes it works sometimes it does not.

[JColvin]

Hi @ojava2018@agruni.edu.ge,

I'm not sure what the problem is necessarily and neither did the other engineer I spoke to, but they found that on the 2020.1 release, https://github.com/Digilent/Zybo-Z7/releases/tag/20/HDMI/2020.1-1, that the red line issue seems to be gone and I was able to confirm this on my system as well.

Of note with the 2020.1 release, you will have to do a couple of extra steps in Vitis before being able to successfully build and then deploy the project, thanks to an import bug in the 2020.1 version of Vitis; these steps are explained here: https://reference.digilentinc.com/programmable-logic/guides/using-github-releases#baremetal_release_workaround_before_programming.

Ideally I'd like to be able to simply inform you how to fix the red lines in the 2018.2 version, but I'm not certain what the issue is and it would be quite some time before we hunted down this error in an older version of the Xilinx software.

Thanks,
JColvin

[ojava2018@agruni.edu.ge]

@JColvin thanks for help, i will move to 2020 seems more stable. i was able to remove that red lines by removing axi stream subset converters which did color rearrangement