Which system do you use? Android, Ubuntu, OOWOW or others?
Android
Which version of system do you use? Khadas official images, self built images, or others?
November Release
Please describe your issue below:
Having issues capturing video from an older legacy device whose only output is 1280x720, the device fails to send video due to EDID values not being present, when capturing the edid values using monitorinfoview
@xiong.zhang when i use an edid emulator you can see the VIM4 now presents with alot more resolutions, AML TV is how it used to be detected and with a EDID emulator its now sees Lindy
Hello, I don’t quite understand what you mean. I checked that there is a resolution of 1280x720p60hz in the code. I want to check whether the edid parameter is inconsistent and causes it not to be displayed. You can connect vim4 to the monitor and use adb to use the following Command to get the EDID of the monitor
This is the node that reads the HDMI EDID number. Your HDMI screen itself does not support 1280X720 resolution. It’s not that our system doesn’t support it.
Hi @goenjoy, I think there is some confusion…there is no HDMI screen in my equation, I have a separate device that outputs a video signal at 1280x720p 60Hz.
The device needs to see the monitor or in my case the VIM4 HDMI Input provide an EDID value that tells it, it supports 1280x720 @ 60Hz for it to output video. Currently the EDID values provided for the HDMI Input are:
I confirmed this by reading the edid value stored in the HDMIRX folder, aswell as plugging a windows pc into the HDMI Input of the VIM4 and reading the edid values from within windows. the HDMI Input of the VIM4 is the monitor in my equation.
If I look at the EDID values of other HDMI usb capture cards like Elgato Cam Link they provide an extensive list where as the VIM4 HDMI Input only provides 4 values.
my windows machine allow you to set the output resolution regardless of the EDID value so I can confirm that 1280x720 is supported by the VIM4 HDMI Input from a video perspective.
Currently to work around this we have a EDID emulator inline which presents a large array of resolution options (see image above)
I don’t have two vim4s at the moment, but perhaps to confirm plug one hdmi output into the input of another. Run the edid command on the one with the hdmi output and check the edid values being presented by the monitor (aka the vim4 hdmi input)
correct, the external device doesn’t output video because it doesn’t get edid value from the VIM4 hdmi input that is required for it to work. (it requires 1280x720)
to confirm the values provided by the VIM4 you can plug one VIM4 into the other, on the VIM4 that has the HDMI output run the following command in adb shell
cat /sys/class/amhdmitx/amhdmitx0/rawedid
this will provide the edid value that looks like
i have then uploaded this to edid.tv which decodes into readable format
@ccsystems We have verified that 720p input can be displayed. What is your specific device and is there a link? Please also provide the kernel log and Android log for reproducing the issue. You can execute it through network ADB. The kernel log needs to be executed after reproducing the problem.
@goenjoy i need to apologise! it would seem that using an edid emulator didn’t actually solve our issue. So we are back to the video source not working on the VIM4 HDMI input, we were able to troubleshoot a bit more and hopefully this can assist in working out why the video isn’t working.
the device is a da vinci xi medical robot
the output according to their manual is DVI-D 720 (1280x720@59.94Hz)
when plugging directly to the VIM4 via DVI-HDMI adapter we get no signal, this image shows the EDID emulator inline, we also tried without to no avail.
weirdly if we take the output of the device and plug into an avermedia game capture hd ii and then plug the passthrough into the VIM4, the signal works
Im not a video expect so im at a loss as to why its not working, it works with other capture devices like elgato CamLink both USB UVC and DirectShow PCI Cards
