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Altera_Forum
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16 years ago

VIP Control is Mutilating my Image!!!

Hello All, I have an interesting problem. I've managed to put together a video processing path: cvi->scaler->frame buf->cvo Which works reasonably well scaling SXGA to SVGA for displa...
Altera_Forum's avatar
Altera_Forum
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16 years ago

Hi Gareth,

Thanks for the help. I'll take a closer look at the hs width consistency both externally and with the SignalTap experiment that you've suggested first thing Monday.

I've seen a few industrial video cards that were design for CRT use that also act 'differently' during either the HS and VS blanking periods. One we saw a few weeks ago had a horizontal line frequency that varied greatly even on the active period of the frame. The monitor it was designed for had a very loose PLL that could track it, but when you try to put an LCD monitor in there a circle looks like an egg!

I think that these changes are not a great idea; a damn lot of PC video cards don't adhere to VESA standards and a lot of old industrial systems were made in pre-cambrian times and are all over the place. There is a lot of work in replacing obsolete monitors and video systems and I hope that I can use the VIP in these jobs to come.

Can I ask what benefits were Altera chasing in these CVI changes?