Xref: utzoo comp.graphics:14398 comp.sys.next:9670 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!usc!ucsd!sdcc6!beowulf!velasco From: velasco@beowulf.ucsd.edu (Gabriel Velasco) Newsgroups: comp.graphics,comp.sys.next Subject: Re: Next machine as animation platform Message-ID: Date: 14 Nov 90 15:44:38 GMT References: <85866@tut.cis.ohio-state.edu> Sender: news@sdcc6.ucsd.edu Followup-To: comp.graphics Lines: 81 Nntp-Posting-Host: beowulf.ucsd.edu From: Kim_Orumchian@NeXT.COM >I think what the discussion below hinges on what is meant by >"broadcast quality". Images that are compressed and played back by a >NeXTdimension are not going to look as good as those produced frame by >frame on a dedicated video production system. Why? This is not a flame. I am really wondering where the deficiency is. Is it in the hardware? The software? The compression algorithm? The original poster was talking about producing the sequences frame by frame. >Another issue is that even though the NeXTdimension's JPEG compressed >images may not be as high resolution as what production houses have >today, I am not at all familiar with NeXTdimension's JPEG compressed images. What type of algorithm do they use? Is it delta modulation? Run length encoding? Send only changes from one frame to the next? Selective color mapping? If NeXTdimension is using 32 bit color (mentioned later in the article) then isn't that *better* than what production houses are using? HDTV is only 24 bit color. How are the 32 bits divided into the three colors? >When Pagemaker came out on the Mac, many people scoffed at >the solution because it did not offer them the same kind of quality as >the high end systems. The point is a new audience was found because >the lowered price point/simplified ease of use appealed to a >different, much broader set of people. I think the same is going to be >true in the case of software products that sit on NeXTdimension. Let's not forget its use in multimedia. I don't think that the "production" quality video systems give much thought to compression because they don't have a bandwidth problem. To transmit these frames over something like the ethernet (We're doing it right now over 10Mbps ethernet in "real-time" with UVC compression boards.) you need compression. A real-time 24 (or 32) bit color video channel would take up a good chunk of an FDDI network too. It seems like the NeXT system may make video e-mail possible. >Also, there are coming high-end consumer-grade >single frame VCR's that would let you image frames with full >resolution (640X480, 32 bits per pixel), and then output them one >frame at a time without doing any compression whatsoever. The author is treating the "compression" like a dirty word. Compression need not decrease the quality of the image any. It depends on the type of compression. What is the resolution of the NeXTdimension video? From: jasmerb@ohsu.EDU (Bryce Jasmer) >Remember what >the NeXTDimension is actually doing when it does compression. It is >taking an image and doing 37 times compression on it. This isn't easy >to do, it must remove some things for the picture and do its best to >get a close approximation. The data going into the compression is not >the same as the data coming out of the compression. This is not necessarily true for all forms of compression. Straight run length encoding preserves every bit of detail in the original image. Delta modulation can come pretty close at a high enough sampling rate. Is it the type of compression that they are using that causes them to lose resolution? Are they mapping the colors into a color map or something similar to what is done for gif images? I may be wrong here, but it seems to me that people are producing "broadcast quality" images with Amiga's outfitted with genlock cards. There are some relatively expensive supposedly professional systems available for the Amiga right now. I've seen pictures of stuff created by the the Amiga that had supposedly been done for KTLA tv station and others. -- ________________________________________________ <>___, / / | ... and he called out and said, "Gabriel, give | /___/ __ / _ __ ' _ / | this man an understanding of the vision." | /\__/\(_/\/__)\/ (_/_(/_/|_ |_______________________________________Dan_8:16_|