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ADV7619 color space filtering issues

Category: Software
Product Number: ADV7619
Software Version: N/A

A customer asked this:

I’m working with the HDMI receiver ADV7619 with the output bus always configured as a 20-bit YCbCr interface. I’m relying on the ADV7619 to do the color space conversion by using automatic CSC mode, but I noticed that it seems to be doing additional filtering on the data when going from 4:4:4 RGB to 4:2:2 YC. It’s pretty obvious putting a color bars pattern through and looking at the resulting output on a vector scope.

 I tried enabling DS_WITHOUT_FILTER and see a difference, but it’s still not correct. It shouldn’t need filtering anyway since it’s going through the CSC to get from 4:4:4 to 4:2:2, right? Is there a way to disable all filtering on the data, and only do the CSC? I don’t see anything that stands out in the datasheet and user guides.

Can you address this?

Thanks.

  • Hi,

       Please ensure with below settings and let us know,

         -->  Set DPP_BYPASS_EN to 1 to use the CP CSC
         -->  Set UP_CONVERSION_MODE to 0
         -->  Set DS_WITHOUT_FILTER to 0
         -->  Configure the pixel output formatter to output a 4:2:2 stream (refer to the Pixel Port Output Modes section) .

    Note: Data Preprocessor and Component Processor are designed to run at speeds of up to 170 MHz. Therefore HDMI video with pixel clock frequencies above 170 MHz must be routed directly to Video Output Formatter bypassing Data Preprocessor (DPP) and Component Preprocessor (CP).

    Thanks,

    Poornima