SDI Delay System

Hi, we are a TV station looking for a system we can use to delay a feed from SDI. SDI is merely a broadcast standard, it runs off coax cables with BNC heads. We need a way to delay by a certain number of frames or milliseconds. Are there any arduino systems that can do this? Professional systems of this can be very expensive.

Maybe one of the 32-bit faster clock boards. That's a lot of data to deal with, 8K bytes in a 2560 or 16K in a 1284 won't handle it.

save it to tape, then with a second head, play the tape.

Seems SDI has to do with digital video with data rates of several Gbit/s.
Out of reach for an Arduino.
Leo..

Standard definition is loosely 270Mbits/sec, while HD-SDI is approx 1.5Gbps.
10 sec delay = 270 Mbytes or 1.5Gbytes of fast RAM...,

Neither of these is going to blink when they pass the pins of an Arduino or other low-end micro. Pretty sweet when you consider the compressed mush arriving at your cable box is between 1 and 8 Mbps per channel... 15 in rare cases.

The only way a simple micro could help, is to design a large realtime RAM buffer, with separate write and read addressing, but the width of the address buss will probably be more pins than you have on a typical processor!
Multiplexing address & data would drop performance by an order of magnitude.

Some of the old SD frame stores used a 68000 processor to manipulate the clocks - but not actually touch the video data. And these were a single frame!

Another technique involves double buffering, so one store is reading, while the other is writing, but these are just methods- you still need the horsepower to process, store and forward continuous streaming media at full resolution.

Newer systems use FPGA style controllers at very high speeds... and consider the amount of RAM, and the bandwidth you'll need to sustain to pump this through.
Non trivial. Sadly, home DVRs and PVRs usually work on heavily compressed data streams, and on,y the last step (the decoder) has to work on a frame or field at a time- with some temporal awareness for compression efficiency). Long story.

An interesting story, but needs a clear requirement, spec and budget.

dave-in-nj:
save it to tape, then with a second head, play the tape.

You could almost get away with that back in the 70s with analog 2-inch tape, but the later formats made it harder - especially as they moved to enclosed cassettes.

Even using disk based delays, it still demands low latency to sustain the throughput while housekeeping is being managed in the background. Often dedicated custom controllers and disk formats to eliminate data fragmentation, and to optimise track stepping.

So in short, it is simply too much data for an Arduino or other micro board and there is a reason professional units are so expensive. Correct?

jackreynolds:
So in short, it is simply too much data for an Arduino or other micro board and there is a reason professional units are so expensive. Correct?

We have a winner!