My opinion on the VC500 'class' of capture dongles is they should cost not a lot.
They all have a demodulator chip, digitizer chip/bridge chip and optionally an audio capture chip.
They are pretty bare bones and you could just about breadboard something a little better.
The Empia 2800 series of chips started out as a microcontroller for connecting a USB cable to a breadboard of parts, gradually with each new generation they added on more 'features' but generally those are of lesser quality than using an offboard (off chip) specialized chip. Its simply that it was not designed to handle video.. using the video capture on the 2800 series of chips is bare bones.. bottom dollar.
With a clear stable video signal.. you may get good video capture.. I've seen good video capture.. but the 2800 series combination is a bucket of parts that is not very tolerant to flakey or unstable signals.
There is no time base correction, no buffering of the frame in case the next frame is corrupt, no attempt to keep the audio and video capture components in sync.. they are separate streams.. its bare bones.. bare minimum capture with no options.. no insurance to compensate for the slightest defect in the video signal.
Its a great "test bed" of parts for learning how to develop device drivers, or learn how video capture works, or how tweaking a video input signal effects the results.. but
In the end.. its mostly for short clip captures.. from a stable source like a camcorder with a tbc built-in (or) for desperate situations where your budget can't afford anything else (or) where you have very little access or the capture has to be done (now) because you won't get another chance.
Using them for hours long video capture with a VCR is probably overstating what could ever be realistically done with one of these. Its good marketing.. but even if you could tolerate dropping a few frames here and there and (some) audio lip sync drift after 30 minutes or so.. it adds up.. until after 2 hours.. you just can't take it anymore.
Capture cards, and larger dongles with capture boards inside of them, have real ram memory and frame stabilizers, or genlock synchronizers.. or even .. time base correctors on their tiny motherboards. They sold at a premium years ago.. $400 or $1000 and there was a real reason. It wasn't that technology suddenly got cheaper.
Each has its place.. and everyone has a realistic budget.
But if you do this long enough.. you'll move on beyond the VC500 'class' and upgrade sooner or later.
Last edited by jwillis84; 07-07-2020 at 05:38 PM.
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