I believe it is in the driver and not in different multiplexers. The windows driver for my card does it. I will conceed that there may be some trickery (odd/even fields, etc.) going on, but it certainly appears faster than what we're seeing under linux. Also, part of the reason for having to drop so many frames is the image color (contrast,etc) fluxuates and takes a bit to settle down. Ryan > -----Original Message----- > From: video4linux-list-admin@xxxxxxxxxx > [mailto:video4linux-list-admin@xxxxxxxxxx]On Behalf Of Arne Caspari > Sent: Tuesday, July 22, 2003 11:17 AM > To: video4linux-list@xxxxxxxxxx > Subject: Re: multiple open()'s on the same device > > > Reply to the mail from Gleicon Moraes (gleicon@xxxxxxxxxxxx): > > > Hi. > > > > That page stats what we all already know: they are selling a > > surveillance system that can be expanded, and claim that you can get 30 > > fps from each board. > > It`s hard to tell you if it is made in Brazil or outside, but > seems like > > a very common bt878 designs. > > I saw some Win32 based software give, or at least do a good mimic, high > > framerates. Usually they dont peak at 30 fps, but the visual effect is > > very convincing. I dont know if they work with a kind of interpolation, > > spliting the ood and even fields and building distinct images... > > Personally, I can understand the input sync problem and why we > can`t get > > more frames per second while capturing and changing inputs. > > But it sure does bother me. I`ve never put my hands in the source code > > for a driver or application under Win32, because usually its closed > > source or need the proper N.D.A. signed. > > > > To get high frame rates from multiple inputs on a single Bt878, the > sources have to be synchronized ( ie. all cameras start to > capture a frame > at the same time ) to reduce settling time. Also the card would > need a faster > multiplexer than the Bt878 provides. > > There are some cards with external multiplexers which act faster > and allow fast > switching of the inputs. > > If you are interested in a Bt878 driver for windows, look here: > btwincap.sourceforge.net > This driver is GPLed. > > -Arne > > > > -- > video4linux-list mailing list > Unsubscribe mailto:video4linux-list-request@xxxxxxxxxx?subject=unsubscribe > https://www.redhat.com/mailman/listinfo/video4linux-list >
