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SOLVED USB grabber wrong colours

Discussion in 'Software Support' started by Refthoom, 30 July 2020.

  1. Refthoom

    Refthoom New Member

    Messages:
    5
    Hardware:
    RPi3
    I've been trying to get this working right for a week now, can't seem to find what the issue is. Help is appreciated.

    The issue is that the grabber displays the wrong colours, like below. A black screen shows as purple, a white screen shows a green. It's not an LED issue, those work correctly.
    - I've tried different grabbers but the results are the same. This one https://www.aliexpress.com/item/32827676511.html and this one https://www.aliexpress.com/item/4000917130635.html.
    - I'm running HyperBian with Hyperion NG 2.0.0 alpha 7
    - It's running on a Raspberry Pi 3B without any issues, The Rpi is hardly doing anything as can be seen from the htop screenshot below. I tried Rpi0W and another Rpi3B as well, fresh HyperBian images, issue remains the same.
    - I have fiddled with settings but this has not solved this issue.

    The only thing i have not changed yet is my HDMI splitter, would appreciate it if anyone shared here if they had similar issues and found them to be related to the HDMI splitter.

    Annotation 2020-07-30 110002.png

    Annotation 2020-07-30 110004.png

    Annotation 2020-07-30 110003.png
     

    Attached Files:

  2. TPmodding

    TPmodding Administrator Staff Member Administrator

    Messages:
    1,699
    Hardware:
    RPi1/Zero, RPi2, RPi3, +Arduino, +nodeMCU/ESP8266
    Hi,
    1. alpha7 has some issues, could you test it with alpha6 please
    2.WHICH grabber do you have (console output from-> "lsusb" please)
    3. did you check the signal direct on a tv and not with the grabber, maybe the issue is somewhere else then the grabber
     
  3. Refthoom

    Refthoom New Member

    Messages:
    5
    Hardware:
    RPi3
    Thank you for the quick response.
    1. Hmmm alright I will give that a try, not today, tomorrow :)
    2. lsusb does not give much information (Bus 001 Device 004: ID 534d:2109) see screenshots terminal and web config page.
    3. not sure what you mean? I have the USB grabber and TV both connected with an HDMI splitter (see photo). It could be the splitter but I switched both outputs and the result is the same. I have spares for all the parts you see in the photo and tested with both leading to the same result, using one SD card to make sure I'm testing hardware only.

    Where can I find a log that I can send, maybe that's helpful too?

    Screenshot terminal:
    Annotation 2020-07-30 153836.png

    From the web config page:
    Annotation 2020-07-30 153837.png

    Hardware setup
    IMG_20200730_154242.jpg
     
  4. TPmodding

    TPmodding Administrator Staff Member Administrator

    Messages:
    1,699
    Hardware:
    RPi1/Zero, RPi2, RPi3, +Arduino, +nodeMCU/ESP8266
    The HDMI Cable which goes to the grabber, could you put it in tv to see if the incoming picture is good, to be sure that the problem is at the usb grabber
     
  5. Refthoom

    Refthoom New Member

    Messages:
    5
    Hardware:
    RPi3
    Yes, I just checked that, TV picture is normal.

    It appears that the hardware startup is of importance for the grabber.

    I've been experimenting with my full set of spare parts (Pi, grabber, splitter, cables and a short piece of LEdstrip) on alpha6 and have had different results. With the alpha6 setup and my laptop as HDMI source I got an okay picture grab but the signal to the LEDstrip wasn't good, flickering LED's. Adjusting baudrate didn't help. Later I switched to a dvd player as HDMI source with the same results, i.e. picture good but LEDs not. Then I switched back to the alpha7 setup and the DVD player as HDMI sorce directly. First had this:
    Annotation 2020-07-31 144329.png

    No matter what I did software wise, I couldn't get it right. I tried rebooting the Pi but no improvement. Then I shutdown the Pi, unplugged it, unplugged the grabber (which is powered by the hdmi's 12V). Next I put the grabber in the Pi first, then plugged it into the HDMI splitter and then powered up the pi. Now I have this:
    Annotation 2020-07-31 144320.png
    This is with size decimation 1, just for testing. With resolution at 720x480, 10 frames/sec and size decimation 4 I get almost no delay. And LEDs are working without any flickering. Also now routing all HDMI sources through my A/V receiver as was intended and all works fine.

    My conclusion: No idea exactly what changed and why it works now. I've had the hardware unplugged several times but it seems that the order in which I connected stuff the last time gave the current result.

    I plan on ordering a different grabber with an HDMI loop in it and see how that performs and if it is less 'sensitive' to the order it receives power. Will come back here to report on it.

    Is there anything I can do (to help) to find the root cause of this strange behaviour?
     
    Last edited: 3 August 2020