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.
bluelip 
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/
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
Koshchi 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.
Hi
Have a look at these sites
http://www.riccibitti.com/dvm.htm
or
http://www.serasidis.gr/circuits/colour_bar_gen/colour_bar_gen.htm
or
http://www.ondraszek.ds.polsl.gliwice.pl/~looser/avr/index2.php
Ken
Hi
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.
Ken
vok07 Hi,
Try Maxim 4455 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3415 .. with this you can insert greyscale images...
