#JPEG and MPEG
12 messages in this thread
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) =-
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.
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) =-
The CD32 FMV module is an MPEG decoder.
—
Dale L. Larson, Intangible Assets Manufacturing
Mario,
Oops! Gee, I guess that would be helpful information! ;-} The CD32 uses the
MPEG standard.
Regards,
John Chang
Technical Support Manager
Scala, Inc.
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
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.
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
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
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?
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
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.