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The Shadow Nitpicking Team requests your assistance.



Well, I finally managed to watch "In the Beginning" last night. Have to admit that the story was interesting and the quality good. It complements "The Gathering" rather nicely.

But, but, but...

If anyone of you has too much time, could you check how one detail looks on your system. I am wondering whether this is an inherent weakness in MPEG2 compression, or simply a flaw in my video subsystem.

The scene in question is at 55 minutes and 10 seconds into the movie. You will reach it via "scene selections" by going to chapter 19 ("To live is to risk").

The camera pans across Delenn's room onboard the Minbari warcruiser, to show Delenn and Lenonn discussing possibilities for ending the war.

During the pan, I saw a most annoying flicker when the movement crossed the light-emitting panels on the wall. Their rectangular pattern seems to periodically increase and decrease intensity, creating an effect slightly annoying at least in my eyes.

Is it truly so that encoding highly regular moving patterns with a high light intensity makes MPEG 2 stumble and fall, producing this annoying flicker? Or is the culprit my computer.

Parameters of my system:

Refresh rate: 100 Hz.
Resolution: 800 by 600 pixels.
Video card: Geforce 2 MX400.
Main processor: Athlon 1000 MHz.
Software decoder: PowerDVD 4.0

I will soon test it with other decoders, but comparison data would be of assistance. Pardon my curiosity in this matter, but this is a tradition of the Shadow Nitpicking Team.
Hmmm... of course, this could be just because my not-so-good eyesight but I didn't detect anything annoying in that scene.

There was an ever so slight flicker when the camera moved so that the 'rope' (or whatever it is that connected the lamp/candle-holder to the ceiling) appeared to move past the panels but other than that, I failed to see anything.

And if I hadn't been looking for it, I doubt I'd have noticed any flickering at all.

Then again, the picture on my TV screen is not crystal clear, probably because it's a PAL set, so that might absorb the lesser flaws.

I didn't bother to check on my computer because when I first tried to watch the DVD in the DVD-ROM, the picture was far from clear and generally a lot worse than on the TV screen.

"Isn't the universe an amazing place? I wouldn't live anywhere else." - G'Kar, B5: Rangers
Kribu's Lounge | kribu@ranger.b5lr.com

I *must* test it with other decoders.

"We are the universe, trying to figure itself out.
Unfortunately we as software lack any coherent documentation."
-- Delenn
As the camera was panning and the flash occurred when the camera was pointed directly at the light source, I would think that the occurance is due to the optics of the situation, not the encoding or playback, and that when you watch it a frame at a time, it is much more noticable than when running at normal speed. In one of the ST series, ST:TNG, I think, there is a similar situation with a wall panel with several vertical light bars, that is on the bridge. It produced all sorts of strange effects, by accident of course. These included the one you mention, plus 'ringing', and strange blurs, and interference patterns, in many eps.

You're speaking treason! Olivia De Havilland as Maid Marian
Fluently! Errol Flynn as Robin Hood
You're talking treason! Olivia De Havilland as Arabella Bishop
I trust I'm not obscure. Errol Flynn as Dr. Peter Blood

Pallindromes of the month: Snug was I, ere I saw guns.
Doom an evil deed, liven a mood.
After testing it with another decoder (WinDVD) I can only conclude that it is either:

1. Something caused by a bad combination of refresh rate (100 Hz, non-interlace) and frame rate (30 Hz, probably interlace).

2. Something inherent to the optics of the situation and the MPEG-2 codec. Something which the flickering light from candles, a high background intensity and a regular pattern greatly augment.

Your idea of looking at it frame-by-frame sounds most promising. I will test it as soon as I can (have to finish one download first, before I can switch back to Windows).

"We are the universe, trying to figure itself out.
Unfortunately we as software lack any coherent documentation."
-- Delenn

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