CompuServe Thread

#JPEG and MPEG

12 messages in this thread
#150093From: Mario van GinnekenJun 1, 1994 5:15 PM
Sorry to but in, but is that FMV has got something to do with the MJPEG standard, as it is called? I've seen MJPEG (that's also picture on 'audio' sized CD's isn't it?) and I think for now it's not that great. I saw a player connected to 2 TV-sets: a normal and a wide-screen set. On the wide-screen set you could actually see the non-moving backgrounds. It was as if they were painted in! If the camera moved a bit you could see the stable background move a fraction of a sec later. Looked awful. But it could be that MJPEG-2 should score better! -MaRiO- -= Intel inside! (…my washing machine) =-
#150221From: John ChangJun 2, 1994 10:22 AM
Mario, JPEG and MPEG are two different standards. MPEG (Motion Picture Expert Group) is a high-compression, full-motion video/audio standard, that can function on low-cost playback platforms. JPEG (Joint Picture Expert Group) is high-compression standard for high-resolution 24-bit and 32-bit still pictures. Since JPEG has been around longer, several hardware manufacturers have developed chips that have the ability to compress JPEG images in real-time (30 frames per second/60 fields per second) for recording of motion picture. The most popular peripheral of this type used on the Amiga platform is the DPS Personal Animation Recorder (PAR), suggested retail price $1,995 US. This card has the ability to playback full-motion video with up to D-2 quality. Unfortunately, there is no JPEG standard for audio. That is why the industry has embraced the MPEG standard. BTW, the PAR should be available in Europe, PAL format of course, very soon. Check your domestic computer magazines for more information. Currently, the MPEG standard has a very low resolution playback capability. Depending on the subjective observer, it is considered more or less the quality of standard VHS. Unfortunately, a real-time, high-quality MPEG encoder with audio and video capability costs approximately $10,000 US. Still, the cost is still low enough to be affordable to the high-end desktop video market. The advantage of MPEG is that one-second of audio/video playback takes, more or less, 300KB. This transfer rate can easily be accomplished by the current double-speed CD-ROM drives. MPEG decoder cards can be purchase for as little as $1,000 US, and the price is dropping as more and more manufacturers get into the market. For commerical, industrial, training and local cable broadcasting, the MPEG standard is acceptable. However, for high-end broadcast systems, most agree that it is not good enough. Hence the as of yet accepted MPEG-II standard. This new standard is suppose to provide broadcast-quality audio and video. However, the encoding/decoding and storage costs are prohibitive for desktop video, literally costing hundreds of thousands of dollars. Currently, there are several modified and enhance versions of the MPEG standard which is considered broacast quality. General Instrument has a variation called DigiCipher-II. A company here in the U.S. called PRIMESTAR, is the first to provide an all digital broadcast service using the DigiCipher-II technology. As a matter of fact, PRIMESTAR also use Amigas and our InfoChannel product for use with their broadcast programming services. It's a small world. I hope you find this "article" interesting and helpful. Regards, John Chang Technical Support Manager Scala, Inc.
#150238From: Mario van GinnekenJun 2, 1994 11:32 AM
Thanx very much, John. I'm complete updated now concerning digital video. BTW: with which of these standards is the FMV-module compatible? I wonder when this digital video-standard will allow writing also. That should take a while though. -MaRiO- -= Intel inside! (…my washing machine) =-
#150242From: Dale LarsonJun 2, 1994 11:57 AM
The CD32 FMV module is an MPEG decoder. — Dale L. Larson, Intangible Assets Manufacturing
#150482From: John ChangJun 3, 1994 9:49 AM
Mario, Oops! Gee, I guess that would be helpful information! ;-} The CD32 uses the MPEG standard. Regards, John Chang Technical Support Manager Scala, Inc.
#150560From: Ottmar RoehrigJun 3, 1994 4:11 PM
John wrote: BTW, the PAR should be available in Europe, PAL format of course, very soon. Check your domestic computer magazines for more information. – Just wanted to add that it _is_ available. And it is GREAT! We are selling it. Contact me via email for more info. Ottmar Roehrig from Hamburg, Germany
#150570From: John ChangJun 3, 1994 4:41 PM
Ottmar, Ah, I'm glad that you have them in stock. Have you tried recording some video in conjuction with a SunRize AD1012 or AD516? Quiet impressive, although we have had some problems getting rock solid synchronizing between the two products. Regards, John Chang Technical Support Manager Scala, Inc.
#150678From: john bennettJun 4, 1994 12:47 AM
John, Good explanation of the MPEG stuff. Can you tell us more about the products Scala has devloped that deal with MPEG encoding/playing? Thanks for Everything :^) ….John
#150686From: Sam YatesJun 4, 1994 1:09 AM
Gday, >> The advantage of MPEG is that one-second of audio/video playback >> takes, more or less, 300KB. 1 second of MPEG-1 video+audio will be around 150KB (180?) (1.5Mbits/s) (give or take). MPEG-1 bitstreams are designed to be played from single speed CD's. (I think CD-I only has a single speed drive, and that plays Video CD's) MPEG-II is around 4Mbits/s and designed for cable/sat. transmission. Sam Yates Montrose, Victoria, Australia. samyates@werple.apana.org.au
#150749From: John Toebes/SYSOPJun 4, 1994 11:10 AM
Ok, I will bite. We have been looking at MPeg encoders and so far there seem to be two realms: The <>$1000 range of low-end boards that do either 15 FPS (hi-res) or 30 FPS (mostly lo-res) with what we would call medium quality at best. The next jump seems to be the PictureTel and Optibase encoders which run in the $20K range. Are there some others you might point me at?
#150534From: Richard DanielJun 3, 1994 1:56 PM
I am not exactly sure what the FMV is based on but I think that it is based around something that you have seen. The system uses MPEG not MJPEG as you thought. JPEG is for use with pictures and is a way of compressing them to tate up less space. MPEG is more or less the same but for full audio and visual pictures. I think it could be based on MPEG-2, I can`t really remember. One thing I do know is that the quality is quite alot better than that of VHS. The still pictures you can obtain from them are perfect with no blurring at all. I managed to have a go on a Philips CD-i version, which is exactly the same as the CD32, and it was very impressive, better, as I said, than VHS. It certainly didn`t look like the background was painted on!! —-Richard Daniel
#150569From: John ChangJun 3, 1994 4:41 PM
Richard, It could have been JPEG, but more exactly Motion JPEG. I guess some have started to call it MJPEG. Indeed, MJPEG does not have the same compression capabilities of MPEG, plus you cannot also encode audio into the MJPEG stream. Regards, John Chang Technical Support Manager Scala, Inc.