analog video signal to vga

Discussion of modular and standalone video generating/processing techniques and associated hardware.

Moderators: Joe., lisa, luketeaford, Kent, daverj

Post Reply
User avatar
neonmercury1
Wiggling with Experience
Posts: 344
Joined: Tue Jan 10, 2017 11:15 pm
Location: Berlin

analog video signal to vga

Post by neonmercury1 » Wed Dec 18, 2019 8:40 am

Hi so im not sure if this or the diy section is the place to ask this but im going to anyway.
So i am looking for a cost effective way to display analog video signals onto displays with vga inputs. i have chosen these displays because they are cheap and readily available whenever an office changes equipment. i am doing an installation part of which is with around 40 or so cctv cameras and monitors. I have seen these video to vga converters on amazon and ebay that look likey they work but are a bit expensive with around 9euro at the cheapest. I am very confident with a soldering iron but cannot design this circuit. i gather from the pinout diagram that i need to slpit the signal into rgb, grounds for each, sync, sync groun, etc. is there an easy way to do this en mass or am i better off going with the cheap Chinese converters that from previous experience can arrive as duds or stop working mid installation sao would have to puchase many back ups. anyone have any ideas

User avatar
joem
Ultra Wiggler
Posts: 932
Joined: Thu Mar 05, 2015 11:07 pm
Location: NYC

Post by joem » Wed Dec 18, 2019 5:56 pm

Those cheap converters are likely using some specialized chip to do the conversion, and without that chip 9 euros is going to be very hard to beat by making one yourself. I think you'd need something like this https://github.com/lzxindustries/docume ... matics.pdf to extract the sync and the video, but you'd also need to do something about the color modulation. I'm not sure exactly how you'd do that, but I think you'd need a PLL at least to lock on to the colorburst sync. Then you'd need to take those ingredients (sync signals, color channel signals) and make sure they're in a format the VGA monitor can handle. I don't think the number of lines for a NTSC or PAL signal are a typical VGA resolution (I might be wrong), so you might need to do some line doubling or something to make sure it fits at a good resolution. Might need to do timing conversion too? There might be a cheap and hacky way to do greyscale video, but it probably won't look very good and color will be much harder/pricier.

The cheap converters may or may not be unreliable, but they're as cheap as you're going to get a composite-to-VGA converter. Any other better, more reliable ones are likely going to be at the 40 euro mark (or higher) at minimum. If you ask in the Video Circuits facebook group, you'll probably get a bunch of good recommendations there, but they won't be as cheap as you want.

Since composite video isn't used much anymore, there isn't a big market to make things that work with it in any way. Otherwise there'd be loads more options. This extends to chips, too. There used to be a lot more chips that did all kinds of neat things with composite video 15+ years ago, but now very few are left. Most that exist now are just big integrated chips for use in HDTVs and such, and they're pretty complicated to work with for DIY stuff.

User avatar
j9k
Common Wiggler
Posts: 212
Joined: Mon Jan 17, 2011 5:00 pm
Location: LA

Re: analog video signal to vga

Post by j9k » Tue Feb 11, 2020 8:16 pm

You can get some hi end switchers for cheap on ebay. Look up ....

Barco or Folsom Presentation pro
barco or folsom screen pro
barco or folsom Image pro
Analog way
Extron
folsom research

Some of them are boat anchors but they do the job if you do your research. What I like about some of them are the extra features for adjusting the image.
http://www.jninek.com/

#muffwiggler irc.mibbit.net

User avatar
DSC
Super Deluxe Wiggler
Posts: 2139
Joined: Thu Apr 11, 2013 11:54 pm
Location: Denver
Contact:

Re: analog video signal to vga

Post by DSC » Sun Feb 16, 2020 11:18 am

j9k wrote:
Tue Feb 11, 2020 8:16 pm
You can get some hi end switchers for cheap on ebay. Look up ....

Barco or Folsom Presentation pro
barco or folsom screen pro
barco or folsom Image pro
Analog way
Extron
folsom research

Some of them are boat anchors but they do the job if you do your research. What I like about some of them are the extra features for adjusting the image.
+1 to this. Extron scalers are great and cheap!

Post Reply

Return to “Video Synthesis”