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Altera_Forum
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14 years ago

flicker in CVO -> CVI -> MIXER -> CVO to output screen

hi, In my VIP chain I'm mixing two video streams (one 800x600 and one 640x480) and then clocking out the mixer output to screen. The two streams going into the mixer are setup such that...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

hi again,

I have some update with regard to the cvo -> cvi issue.

It seem I was using a 40MHz clock for both the cvo and the cvi when clocking the 640x480 format, when infact the pixel clock for the 640x480 @ 60hz should be 25.175Mhz.

So now I'm using 25.175MHz for the cvo. For the cvi I'm using different clocks for the video input (25.175MHz) and the video output(40MHz).

Although the 640x480 overlay flickering is now almost gone, the 800x600 output flickers after a couple of seconds and also there is some distortion at the top of the video output (seems like a couple of the top lines have been shifted to the left).

If someone can help me out here, it would be greatly appreciated