Help on digital video project 4

[GonzaloEE]

Hi you all, I'm new here. I'm working in a project where I need to convert an analog video signal (PAL or NTSC) to MPEG and JPEG, to either display it in a graphic screen or store files in a SD flash card.

This might sound much like those digital cameras, though there's no need for CCD/CMOS camera input as many video ICs expect.

I'm not a digital video expert, so I'd really appreciate any guidance on custom ICs or design approaches.

The client is reluctant to using CPUs or hiring programmers, so I'm willing to get a fully hardware solution, with minimal need for firmware.

Thanks in advance,
Gonzalo

 

[IRstuff]

May be something along these lines:

http://www.analog.com/en/subCat/0,2879,765%5F810%5F0%5F%5F0%5F,00.html

TTFN

FAQ731-376

 

[itsmoked]

Half the new video cards take in video PAL or NTSC and spew it out to mpeg files. Heck, I think I have 4 different computers that will do that myself. Then copy over to the SD. If the data rate is low enough you could probably just log to the SD and go onto it directly,(have to think about that).

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[GonzaloEE]

Thank you!

IRstuff: Nice devices. From the block diagram, looks like I need some NTSC/CCIR converter beside the chip. I'm reading further to have a clearer picture of it.

Keith: Agreed I'm closing to something like a PC TV capture board, and the need of lower bitrates in case the client wanted a sort of video logger (a punishment for a flash, anyway).

The client wants a 12V powered box with much of the commerce digital cameras: some push buttons, connectors for external LCD screen and analog video input. Also, he wants a SD memory socket and some GUI menu. Expected production is 100-200 units.

I suggested an ARM processor but he doesn't like paying for firmware, so I'm leaning for something like this:

http://www.zoran.com/COACH-10

Unfortunately, these guys doesn't pick the phone for orders of less than 100,000 pcs

Further guidance is highly appreciated!

Regards,
Gonzalo

 

[itsmoked]

Yes I just went through a hassle with those turkeys. I had a chip-in-hand and they couldn't be bothered to cough up a data sheet.

I knew a medical company that took an off-the-shelf camcorder, gutted it, and made it into an arthroscope unit.

For only a few hundred you might consider a similar scheme. You do have to be careful and if you consider this route there are several gotchas that we should discuss.

Perhaps you can use a small single board PC that you can just sort-of batchfile standard SW with.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[VEBill]

It sounds like the functional and I/O requirements could be met with a small low cost laptop PC (something like the $300 EEE-PC), with a USB video capture dongle.

 

[GonzaloEE]

Thanks Keith. Adapting an existing camera is a option. The SBC sounds very good, just like those old ATM and POS machines. I'm still thinking that a simple program in WindowsCE or Linux could help a lot to the H/W.

VE1BLL: A laptop based it's a very logical approach, as any TV capture or surveillance software has almost all the customer wants: video capture, flash card backup, GUI, etc. In fact, The customer originally wanted a s/w solution, and I pushed for something on board, obviously to get the job.


I'm a PCB designer, so suggesting ready-made solutions puts me off the business. I thought I could handle this by designing a board from scratch, but now I'm re-thinking this.

Thanks for your help!

Regards,
Gonzalo

 

[GonzaloEE]

Hi Keith. About taking an off-the-shelf camera, I guess the main problem is the need to match the signals.
As far as I know, most camera controllers expect a digitized 12 to 14 bit signal from the CCD/CMOS sensor. As the client needs to process NTSC video signals instead of a webcam-like output, I thought we must add some video decoder stage and some analog front-end stages.

This would mean doing some 'surgery' an the camera board. Isn't it too risky?

Regards,
Gonzalo

 

[itsmoked]

Yes that would be risky!

How about those mini boards that stack. I forget the name of them. It's an industry standard. Use one that runs WinCE or Linux and you can plug in a USB video capture unit like V suggests.

You are really limited by your customer's proscription of much coding.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[geekEE]

Keith, I think the stacking boards that you're talking about are PC/104-Plus, which is essentially the PCI bus signals on a board with stackthrough connectors.

 

[itsmoked]

Thanks geekEE! That's exactly what I was trying to remember.

Regards,

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[GonzaloEE]

Thanks guys! PC104 sounds fine (thanks geekEE, I didn't recall the name neither). I'm talking with the customer about this.

I will post here how is it going.

Regards,
Gonzalo

 

[Barmaley]

Recently I was asked to do the same job. But to convert analogue video to digital I have used AXIS 241 network video server. Because it has an open HTTP protocol specification.

The only one problem I've got is a netowork traffic from 12 cameras - it was more than 100 mbits/second so I was need to switch to 1 GBit network.

For such cases I found a really excellent bandwidth estimation software - from

http://www.jvsg.com

So for next projects I calculate traffic at first and then purchase network switches.

 

[Barmaley]

Addition: I have used Motion JPEG instead of MPEG4

 

[GonzaloEE]

The BW estimator looks great, though this project has already been finished.
I agree that over certain speed, it's much better switching to some networked approach. There are also plenty of IP-cameras and networking solutions off-the-shelf.