CompuServe Messages

#VTR Skipping Frames

    30-Aug-93 11:45:12
Fm: MARTIN G FOSTER 70303,456
To: Michele Bousquet 100237,162
Michele, >>1. A Jpeg card would ordinarily come with its own software to compress >>a list of TGAs to an animation file; Yes, this seemed to be the case for the ones I saw at Siggraph. >>2. When you want to view the 24-bit animation you must put it out to >>video, you can't view it onscreen, say on a Targa+ (until further >>technology permits) so a home VCR is ideal for inexpensive previewing; Not exactly, you can view the animation by playing it in real-time out to a monitor from the JPEG card. Similar to how you view a flic, except much higher quality and it is recordable, if you wish. >>is the compressed file file bigger, smaller or similar to the original >>space taken up by the Targa files? considerably smaller. Say from 10 to 30 times smaller. >>2. Would the realtime output to BetaSP sometimes not be as good as >>frame-by-frame because of quality loss from compression? Or could you >>just use a low compression ratio and save the quality? Or if the >>compression ratio is low the Jpeg card cannot keep up with 30fps? The quality will not be as good as BetaSP, although they often call it near-betaSP quality at the highest quality setting. They may be a situation where there is so much moving on the screen that you need to lower the quality to maintain a fixed 30 fps. >>A note: I am in PAL-land so 25fps is the concern, not 30, if this >>makes a difference. The manufacturer would probably have to make a PAL specific card, or one the does both PAL/NTSC. Hope that helps.