tin wrote:Aha, I had seen this, thought maybe there were more images somewhere showing more detail.
One thing that interests me with this page is that it says that sneak prevue had it's own satellite feed as well as the laserdiscs. Do we have any information about that? I will go and watch the videos again to see if I can see the switching between the two
I believe some versions of the Prevue Guide software had the capability to switch between satellite and LaserDisc, but I don't believe that Sneak Prevue could ever do this, simply because I don't think they ever had a satellite feed dedicated to it.
But wait - according to the Big Book of Amiga Hardware, the Sneak Prevue used the same Zephyrus model 101 data demodulator as the regular Prevue machines. In fact, as Steven suggested, the Sneak Prevue must have used the same satellite data feed as the regular Prevue Channel, simply for the channel numbers and start times. It is also likely that the LaserDisc timecodes were sent over satellite as well. This is really fantastic news for us, since I believe I might be able to get the Sneak Prevue source code in a little bit, which could help us finish up documenting the protocol (and maybe we could figure out the Amiga mode K!).
tin wrote:Yeah that's a bit of a shame. I read some comments on the video at
http://www.youtube.com/watch?v=NlkLDFOgJe4 and am interested about the "flip out" comment. I wonder if it flipped out if the local operator did not change the disc on time? After the videos Bolt96 posted, it looks like the Amiga would seek the disc to exact times for video/static backgrounds and audio. So if the Amiga was seeking to times meant for a different disc, I am sure that would look like some flipping out! Or maybe they were a bit cleverer than that, and the flipping out was just standard bugginess. To be fair, prevue guide is clearly quite buggy so I doubt sneak was much better.
<edit> having a think about it all, they should have made the system have 2 videodisc players. It could have queued up one while the other was playing, or used one for continuous background music while various branded promos were playing. I find the audio stopping for 1sec over and over again jarring. Maybe that would be too expensive...
I would guess, like you are saying, that the Amiga would at some point send updated LaserDisc information and timecodes, at which point things might go awry until the LaserDisc is replaced. Maybe Prevue Networks instructed cable companies to put the LaserDiscs in at a certain time (i.e. exactly 8 AM on Monday or whatever). I do know that Sneak Prevue started out as a completely new project, and was not based off of the Prevue Guide, although I heard at some point that there was some code sharing between the projects (likely the satellite data parser and the LaserDisc controller).
Of course, 2 LaserDisc players would have been better, but that would definitely have been more expensive. The thing is, although the stopping at the end of music or a promo is a little bit jarring, it really isn't an issue at all during the previews themselves, because the LaserDisc always pauses on the title card of the program.
I do notice, however, that the seek time in the video you linked to seems to be worse than the earlier videos I saw. Maybe that LD player was having some issues?
nwgatwcfan wrote:tin, to answer the first question. On the back of the LD-V8000, there were three inputs on the back for the video. I'm thinking that on the UVCOM board, these were loopbacks to the Laserdisc player. The LD player had the ability for text to be overlayed over the video playing. I'm wondering if it was for this reason the UV card that the multiple outputs. Might also explain a previous post when they were trying to run the Prevue Guide software that there was no sound, etc. Their system may have been setup for Sneak Prevue only. You may want to investigate this further.
I don't really think that's the case. The Amigas definitely overlaid all text themselves and did not make use of the built-in character generator.
If it helps anyone, here are all of the pictures of the UVCOM4 that I know of (came from BBoAH and swest77):
http://cl.ly/0t171c2L3S3q2d252H1p
I really wish I could read that label above the card on the one picture of the back of a Sneak Prevue machine, but sadly it's too blurry. It looks like it says something and then "card". So I'm still a bit confused about those ports. Maybe higher-end setups supported multiple LaserDisc players like tin suggested?
