Hi Georgios, It's going to have the exact same bt8x8 chip that the non-tuner posessing video grabber has. Note, btw, that if you use composite in, the tuner is not used anyway. It's just sat there on the capture board doing nada. One other thing you might not have spotted: the bt8x8 does bus-master. The latency through the capture/dma cycle is going to be pretty negligable as the bt8x8 does not have enough buffer ram on-chip for a full frame. This can lead to other issues of you have a shoddy motherboard pci implementation (latency and corrupted frames). Your expensive frame grabber on the other hand, -might- have oodles of ram, and large on-card latency. It will be hard to have a significantly lower latency than the bt8x8 though. Some other personal opinions: If you're doing something 'critical' with machine vision you want redundancy anyway. Not some hand-waving mtfb calculation (spoken as someone working in the space satellite production field). Tis your project's money though, not mine. You've seen plenty of suggestions on the list for bt8x8 cards without tuners, and other frame grabbers if you really want something that isn't just a brooktree(as was) reference-design clone with varying amounts of supporting circuitry and customization. Mark On Mon, 2002-10-21 at 21:20, Georgios Kapetanakis wrote: > You may be right about economies of scale, but would you trust a WinTV card > for a real-time machine vision application? (and I stress the words 'real > time') > > -- > Georgios Kapetanakis > Department of Computer Science > University of York > > > ----- Original Message ----- > From: "Martin Peach" <martinrp@xxxxxxxxxxxxxxxxx> > To: <video4linux-list@xxxxxxxxxx> > Sent: Monday, October 21, 2002 8:08 PM > Subject: Re: Frame grabbers with bt8x8 chipset > > > > Georgios Kapetanakis wrote: > > > > > > I don't want a TV/Tuner card.. thingy, because I want video only. No > sound, > > > no frills. Just video. Fewer things can go wrong this way ;) Also, frame > > > grabbers typically support bus-mastering, which is good for real-time > > > capturing, i.e. more predictable and more reliable. I might be wrong, > but > > > that's my requirements. > > > > I'm just saying that economies of scale mean that tv cards cost less > > than video-only cards and otherwise work the same. I think a WInTV costs > > aboout 1/10th of a Meteor and I can't tell the difference. The unused > > parts effectively go to sleep if you don't use them. > > > > /\/\/\/*=Martin
