View Full Version : Mpeg2 encoding


Brad Simmons
April 23rd, 2003, 12:57 PM
Hello, could somebody give me an advice with one annoying effect I came across...

I've been capture and edit with ULEAD 7 Pro, encode to MPEG2 with TMPGEnc. At the end watching the movie on the PC screen shows unwanted trails when objects move fast, even not that fast at all. It's almost like the shape of the moving object is smeared. When the scene is almost static it has very good quality indeed but when you turn the camera or the object moves everything smears.

The same the effect if I capture from the camcorder with Pinnacle or Premiere. I do not suppose the encoder to have a lot to do with this? On the TV screen there is nothing like this. Maybe the videocard I use – Nvidia MX400, 64MB RAM has something to do with it?

Any suggestions would be welcome.

Rob Lohman
April 25th, 2003, 06:25 AM
Are you saying you are seeing this effect NOT on your TV but
you do on your computer? And this happens with the original
footage as well as the encoded footage?

If so I think you just set your shutter speed to low (below
1/50 or 1/60) when recording the footage. TV's might indeed
be a little bit less in showing this effect than a computer due
to the way the display the signal.

Brad Simmons
April 25th, 2003, 06:35 AM
thanks Rob,

Yes, I am only seeing this effect on my computer monitor, NOT on my TV . However, this happens only with the encoded footage, not the original footage.

I'll try changing the shutter speed though, but I really don't think thats the problem because it looks fine until I encode it.

strange eh? I might try borrowing someone elses video card to see if that changes anything.

Zac Stein
April 25th, 2003, 06:51 AM
This could be a result of watching interlaced footage back on a computer monitor, it would look as if the image is breaking appart and smearing.

When you watch your footage in an NLE most nle's do an on the fly conversion to progressive scan for editing purposes, then when you do your final output it gives an interlaced file back ready to be burnt. On your tv the footage would appear totally normal.

Anyways, that is what i think.

Zac

Rob Lohman
April 25th, 2003, 07:37 AM
Brad,

Did you shoot the footage in interlaced or frame/progessive?
What settings did you use for TMPGEnc? Did you tell it that it
is interlaced or frame/progressive?

What software did you use to playback the MPEG2? I've had
some bad experience with Microsoft's Media Player (especially
with incorrect aspect ratios and such). Try a software DVD player
to see how it looks there.

Alex Dunn
April 25th, 2003, 09:02 AM
I think it's an interlacing issue. I had a similar issue where the interlacing would smear after being encoded. I don't have a fancy de-interlacer, so I started shooting in Frame Mode which is basically a camera based de-interlacer. Then I upgraded to Ulead's latest MPEG2 codec (from MainConcept) and my latest stuff is A++.