I'll start out by listing my hardware: -Athlon 500 Mhz processor -128 Mb SDRAM -ATI AIW 128, 32Mb AGP capture card -Sound Blaster Live! Sound

Software listing: -ATI Television to capture -ATI Video Editor to recompress with a different codec -Adobe Premiere 5.0 to edit and render to AVI -Adobe After Effects for animated clips -MPEG1 Encoder

Here's my problem... I've created many operable VCD's in the past, always attaining a better quality with each new project. My most recent VCD was created from a captured AVI using the ATI VCR 2.0 codec, then recompressed using the Cinepac codec(this was done to make it compatible with Adobe Premiere 5.0). I then edited the video with Premiere and rendered it using the same Cinepac codec with VCD video parameters. The last step was to encode to MPEG1 using the Panasonic MPEG1 Encoder. I was VERY PLEASED with the quality, except for one thing.... there is a distortion 'pulse' on the video about every second or two. If not for this 'pulse', my VCD would be VERY near VHS quality. This pulse is put in the video when rendering to AVI from Premiere and After Effects.

If there's anyone out there that can explain this to me, I'd GREATLY appreciate it.

Thanks in advance for your time.

-- Robert Snider (rsnider1@san.rr.com), September 27, 2000

Answers

Hi Robert, Distortion pulse? What is your source material? I am not familiar with ATI, but is it copy protected? I have encountered a macro vision protected tape that do just that. It was my friend's graduation video that was made by professional video service on the spot, and they sell the tape right after the ceremony:) Yet it has copy protection in it. It must be easy to make such tape, huh? He asked me to convert it to VCD, and when I capture it to AVI, the result is similar to what you have.

If it is macro vision, you would know it by just dubbing the tape to another tape. If this "pulse" exists in the copied tape, then it is copy protection.

Not sure if ATI let you capture macro vision tape witout warning. My Broadway didn't warn me. My Matrox Marvel refused to capture it (until you apply the hack, of course).

-- Rusman E. Priyana (priyana@eudoramail.com), September 27, 2000.

Thanks for the info, but as I stated earlier....the distortion 'pulse' came into my video when I rendered the AVI in Premiere and After Effects. My source video was from a camcorder, composite connection. The distortion pulse isn't severe and is barely visible when the video is played on a PC at 352X240. It's magnified though when stretched on the TV screen with a VCD. Thanks for your time though. I'm hoping someone else out there has had the same experience or at least knows the solution to my problem.

-- Robert Snider (rsnider1@san.rr.com), September 28, 2000.

I think I know what U mean. This "pulsing" really is barely noticeable and can be forgiven, except when 1) watching on a big screen TV (>25") and 2) viewing scenes that have very little or no motion in them. Most video have a fair amount of motion in them and the good quality Panasonic produces conceals this "pulsing" (visible on large expanses of still single color, where blocks/patches ever so slightly seem to "throb" or "gyrate" (!)). I haven't really tweaked Panasonic to reduce this because it doesn't bother me with the type of videos I commit to VCD but in TMPGenc, there is a part where some of this effect can be alleviated (something like "soften macroblocks...fine moving details will disappear, etc...") I was told once it may have to do with the way MPEG is: the picture quivers a little (?) everytime an I-frame comes, which by default in most encoders is at least twice a second (GOP=15, NTSC), and the "pulsing" we note is the beat between that and the actual framerate. TMPGenc has an option to "close" GOPs (which may or may not help) but this is with a view to editing the created MPEG stream (usually for those who will want an all-I-frame MPEG-2 stream).

-- M Tekdemir (turk690@yahoo.com), September 28, 2000.