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Hi,
I did a search on the forum but I couldn't find what I was looking for. I'm trying to build a circuit with an AVR which can add text over a video signal. I know there are some chips out there that can do this under microcontroller commands. Anyone has any experience with this or can point me in the right direction?

The video signal comes from a digital camera and I want to be able to add text to it before it gets to the video recording system.

hachey
... to boldly go where no AVR has gone before...

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Have you seen Cornell's EE476 final projects page? They've done quite a bit of work w/ atmega32's.

http://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/

Mike Coles http://blips.net
'bluelip' http://diyaday.com

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I believe that Maxim has a chip that is designed to do exactly this. I used to use some very nice ones from NEC but they went obsolete. There are some at Mitsubishi or its successor (whatever the name is) but they were quite limited (number of characters per line, number of lines on the screen) and they really didn't work that well in the demo. I used to do a lot in this area.

I can do some searching if you need more info.

Jim

 

Until Black Lives Matter, we do not have "All Lives Matter"!

 

 

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You could theoretically do it with just an AVR. You would need to detect the sync signals to get the timing right. After that, the text itself wouldn't be hard. You may even be able to get color to a limited extent, but it would be hard to lock on well enough to keep it consistent.

Regards,
Steve A.

The Board helps those that help themselves.

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Hi

Quote:
The video signal comes from a digital camera and I want to be able to add text to it before it gets to the video recording system.

Just exactly is the video recording device ?
Is it a PC video frame grabber or VCR unit?
If using the PC, then why not get a video program to add the text in for you. Nothing to build.
For VCR then you will need build something to interface it.

Ken

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Hi,

Try Maxim 4455 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3415 .. with this you can insert greyscale images...