CompuServe Thread

JPEG and MPEG

2 messages in this thread
#150780From: John Toebes/SYSOPJun 4, 1994 1:08 PM
Actually, you can control how much space an MPEG stream will take up based on the number of I frames, the quality of search for equivalent macro-blocks, and just the general encoding technology. While at Comdex I got a chance to see several demos of quality range from 100KB/sec all the way up to 450KB/sec. Surprisingly, the size is not always the major factor in the quality of the end result.
#150977From: Sam YatesJun 5, 1994 7:55 AM
Gday, >> Actually, you can control how much space an MPEG stream will take up >> based on the number of I frames So you can. 🙂 I thought the discussion was about Video-CD applications. I was under the impression that: a) The MPEG-1 standard set down a 150KB stream. b) The MPEG-1 specification allows you to have any stream size you like, but the resulting stream will not be compatible with all MPEG-1 standard decoders (eg. CD^32+FMV, CD-I etc). >> Surprisingly, the size is not always the major factor in the quality >> of the end result. I have read that good MPEG encoding _REQUIRES_ operator intevention to decide what should happen when the source material changes scenes quickly etc. This makes me suspicious of the real time MPEG encoders that are availible. (ie. They can't be high quality if operator intervention is required.) The quality of the output is directly proportional to the experience/talent of the operator. Sam Yates Montrose, Victoria, Australia. samyates@werple.apana.org.au