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Electronically splicing two composite videos inputs together

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Zephyr

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G'day.

By the way, Nigel, if you're reading this, thanks for introducing me to PICs. Currently onto the MikroPascal compiler, and experimenting. I can't say i've been going too far, however.

On to my topic. I've got two cameras, both with a composite video output - but my monitor has one input. What I want to do is to "splice" those two signals together into a video signal with both images side by side, which then can be inputted into the moniter.

If it helps, both cameras are the same model, which means they probably have the same frequency, etc. Basic cameras.

E.g. **broken link removed**

I'm treating this as yet another learning experience.

Thanks.
 
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Treat it as a 'buying experience' instead, you can buy units to do four (or more) cameras in this way, it's not a project that would be buildable at home.
 
Hm. Are you sure?

If you are, because i've seen units that mostly go for above the $500 range, which is quite a bit above my budget.
 
If you have a PC and a multi-input DVR card (google "quad input dvr card"), it could be done significantly cheaper (provided you have an old spare PC lying around, of course)...
 
Perfect, thanks.

I suppose adding a HUD to a composite signal would be horrible as well? As in overlaying some data from a I2C onto a composite video.
 
Perfect, thanks.

I suppose adding a HUD to a composite signal would be horrible as well? As in overlaying some data from a I2C onto a composite video.

You can do it using on-screen display chips used in TV's, VCR's etc.

Main problem is finding datasheets for them (I used an old NEC chip when I did it) - so the easiest solution is to use this ready built one:

The BlackBoxCamera Company Limited - PIC - OSD Project Board
 
Since your composite signals have different frequencies you cannot easily merge them. You'll need to digitize them, store a frame of each in a buffer, do some processing, and emit a video signal with the result. Of course, a PIC cannot do that. There are chips which integrate all the necessary stuff, which are used in video surveillance boxes. It would not be too simple though.

Get a second used monitor for $50.
 
They would ahve different frequencies even when coming from the same brand of camera?

It's not a question of 'frequency', they need to be solidly syncronised as well - and domestic equipment doesn't have such facilities.

As we've told you, it's not easily or cheaply possible - you need to digitise and memorise every single frame, digitally rescale them both, join them together in the format you want, and them output the resulting combined frame - all in real time.
 
It's not a question of 'frequency', they need to be solidly syncronised as well - and domestic equipment doesn't have such facilities.

As we've told you, it's not easily or cheaply possible - you need to digitise and memorise every single frame, digitally rescale them both, join them together in the format you want, and them output the resulting combined frame - all in real time.

So, you're basically saying that an Amiga with Genlock can't exist today - interesting...

The truth is, with a PC, all of the above is easily possible, and fairly cheap (as long as you're not going out and buying a new PC). Get one of those multi-input DVR cards, there's your digitizing hardware; if you get one that is based on the BT878 chipset (as well as a few others), you can drop a copy of Ubuntu on that box, then load up ZoneMinder and have a -very- professional security camera/DVR/monitoring solution like you wouldn't believe. ZoneMinder and Ubuntu are both free, by the way. I've got it set up right now on my workstation, monitoring a WiFi camera that points out the window of my house. When someone walks by (I have custom zones set up in the camera's view to adjust the sensitivity and area of the image I want to monitor), it analyzes the video, time-stamps the images, records a video of the action w/timestamp overlay (5 seconds behind the trigger and 5 after), emails me a picture and a video to my cellphone, and stores everything in a mysql DB, for later recall, playback, etc. I have only one camera, you could have many, many more (it also supports PTZ mounts, external triggers, etc). Oh - everything is done via web interface, too; your cameras don't even have to be on the same continent as the server (latency and such would suffer, though - so keep it on the same subnet in a different part of the city at least).

Seriously - you could take your favorite Linux and ZoneMinder, put them on a 1U server with a small RAID array, and sell it along with a bunch of WiFi cams as a custom, turn-key security solution.

Of course, I will say that I don't know what Zephyr's real application is; it seemed like security monitoring.

Ultimately, though, any "PC" made in the last 15 years could do what you're talking about, and if you went back to 1985 - the Amiga could, too (although, in 1985, getting such a setup would be fairly costly, though certainly much, much cheaper than the commercial video processing offerings at the time). One would think someone from the UK would know that...

Today - find an old PC made in the last 5 years (heck, I've probably got 5 sitting in my shop here at home) - drop a cheap video capture card on it (quad-DVR cards are cheap), and run some software (most of those cards come with something for Windows; you can also find other software offering out there - my preference has been with ZoneMinder on Linux - which is a free and -very powerful- security camera solution).
 
So, you're basically saying that an Amiga with Genlock can't exist today - interesting...

I made no such suggestion, a genlock is an entirely different device to what we're discussing, and has no bearing on this thread.

The Amiga hardware was designed with the capability for genlocking, so there's no massive digital processing required, the Amiga hardware is simply locked to the external sync.
 
I made no such suggestion, a genlock is an entirely different device to what we're discussing, and has no bearing on this thread.

The Amiga hardware was designed with the capability for genlocking, so there's no massive digital processing required, the Amiga hardware is simply locked to the external sync.

You wrote:

they need to be solidly syncronised as well - and domestic equipment doesn't have such facilities.

What does it matter how it happened; the Amiga synced with a signal - and was a piece of "domestic equipment"; I've already provided an explanation of how what is needed to be done can be done with today's "domestic equipment" - and we still don't know for certain whether "solid synchronization" is absolutely needed for the timestamping; the OP didn't state he needed SMTP time-coding, he just wants a simple timestamp (and maybe some other info) overlayed some video, from all appearances; video which is coming from one or a few (apparently) simple video cameras. This can easily be accomplished with "domestic equipment", in the form of a PC; for that matter, you can even do SMTP timecoding on a PC if you wanted (it won't be inexpensive, though).

I'm arguing that it is possible to do what is being asked for using common OTS equipment that is available today; you seem to be arguing the opposite - I am curious why (maybe I am misunderstanding you; maybe I am misunderstanding what the OP wants?)...
 
You wrote:



What does it matter how it happened; the Amiga synced with a signal - and was a piece of "domestic equipment"; I've already provided an explanation of how what is needed to be done can be done with today's "domestic equipment" - and we still don't know for certain whether "solid synchronization" is absolutely needed for the timestamping; the OP didn't state he needed SMTP time-coding, he just wants a simple timestamp (and maybe some other info) overlayed some video, from all appearances; video which is coming from one or a few (apparently) simple video cameras. This can easily be accomplished with "domestic equipment", in the form of a PC; for that matter, you can even do SMTP timecoding on a PC if you wanted (it won't be inexpensive, though).

Perhaps you should try reading the thread? - he wasn't wanting to timestamp a video signal, he was wanting to combine two video signals side by side on a single screen.

He only mentioned the overlay question later on, where we told him how to do it fairly cheaply and easily.

I'm arguing that it is possible to do what is being asked for using common OTS equipment that is available today; you seem to be arguing the opposite - I am curious why (maybe I am misunderstanding you; maybe I am misunderstanding what the OP wants?)...

You are misunderstanding BOTH :p
 
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