CompuServe Thread

#Pulling Hair Out! Help!!

2 messages in this thread
#4412From: Linda EdelenApr 5, 1995 8:21 AM
I am making a Macintosh QuickTime movie that will have both digitized video and pict images. The finished movie will be 320 x 240 at 15 FPS. Because of the digitized video I am forced to use Cinepac compression (otherwise I would use animation compression for the picts). I have run about thirty test and have found a problem that I can't resolve. I have created 2 images in Photoshop 3.0. both images are 100 % cyan bold type on a solid grey background. The images were both saved as indexed color (8 bit/system palette/diffusion). My intentions was to import the images into premeire 4.0 and make sure that the cinepac compression wasn't going to make them look too bad. I think I have found that the cinepac compression gives me the quality I want but the keyframes setting is making my images look horrible. The first test I ran I imported a single Pict image (from now on referred to as 1A) into the premiere video track A, gave it a duration of 1 sec and made a QuickTime movie set to 15 fps/keyfrm every 15 frms/ Limit data rate to 150k per sec. The quality of my first test was acceptable to me. The problem is when a do everything as I have stated for the first test but add another 1 sec pict image (2B) next the first image (1A) in the premiere video track A. The second image's quality deteriorates terribly. I tried changing everything that was a variable but could never get the second image in the movie to look acceptable. I then tried switching the two images the second image is always the one that looks bad no matter if it happens to be 1A or 2B. What gives? Personally I think it the Keyframes setting. Because I can't change the quality level (because this movie will eventually run from a CD-ROM) I must find a way to make Premiere set a new keyframe at the beginning of each new pict. I thought to accomplish this all I would have to do is make sure that each additional pict starts at an the beginning of a new second , frame 1 (in other words no images starting in the middle frames of the 15 fps – tryin to make each pict start on the whole second marker). This did not work either!! I tried lengthening the first image to two second and the second image to 2 seconds. As before the first image looked fine but the second image looked bad. I need help. If there is anyway you can help me resovle this problem please do. P.S. – I also tried using differnt video tracks in permiere changing bit depth of images, not indexing them,etc….
#4440From: Jeff SauerApr 6, 1995 8:24 AM
Willliam: This is an interesting problem and I'd like to be able to follow your progress. I'm not sure I have much of an answer, but I tend to agree that the problem sounds like a keyframe issue. Naturally, if a new graphic starts before a keyframe, there will be lingering images from the past graphic. What is really needed is a way to force keyframes. Your attempt at just that was a noble one, but it seems to me to be a strong possibility that the technology is not supporting it. I don't know that for a fact. It's just me guess. Have you tried keyframes much more often (forgetting data rate for the moment)? If the second image looks better you'd be sure it was missing the keyframe. The only other thing I can think of is to put a matte between the two graphics that would get through at least one keyframe. Let me know what you find. Jeff