aspect ratio conversion problem

[bmwracer]

Hi everyone,

Got a Japanese NTSC TV-movie from a friend and noticed that the aspect ratio was distorted: the video is sorta squished.

I re-processed the MPEG2 video to 16:9 using TMPGEnc Plus and the aspect ratio looks fine, but now the motion in the video isn't very smooth at all... It has a "streaky" look to it as if the characters are moving really fast. Audio is just fine, though.

Any thoughts on why the aspect ration conversion affected this? And how do I correct this?

Your help would be greatly appreciated.

[guns1inger]

Does this only happen when watching on the PC ? (i.e. have you tried burning to an RW to test it out ?)

Was the source interlaced ?

When you saved it out, could you have saved it out as interlaced ?

Streaks can often appear on the PC when displaying interlaced source. This is normal, and usually wont appear on you TV.

The only other thing I can think of is that something strange happened when interpolating new pixels when you resized the video.

[bmwracer]

Does this only happen when watching on the PC ? (i.e. have you tried burning to an RW to test it out ?)

Was the source interlaced ?

When you saved it out, could you have saved it out as interlaced ?

Streaks can often appear on the PC when displaying interlaced source. This is normal, and usually wont appear on you TV.

The only other thing I can think of is that something strange happened when interpolating new pixels when you resized the video.

Hi... Thanks for your response.

The motion problem occurs when watching it on my PC and on my TV (Yes, I did burn a DVDRW to test... forogt to mention that... Sorry)...

Interestingly, I was just fiddling with the settings and when I changed the output to non-interlaced (input source is interlaced), it seems to have fixed the problem... I'm sorta at a loss on why this apparently corrected the problem, but I can't argue with results.

If anyone has a technical explanation, I'd like to hear it from an educational standpoint...

[guns1inger]

You should not see the interlacing on the TV, unless, perhaps, you have the field order reversed. All TV programs broadcast over the analogue network are interlaced, yet you don't see it.

Depending on the method used to deinterlace the footage, you might have thrown away half your resolution by discarding one of the fields, or blended the two fields together using one of a couple of methdos. Eitherway you have ended up with a progressive movie.

[bmwracer]

You should not see the interlacing on the TV, unless, perhaps, you have the field order reversed. All TV programs broadcast over the analogue network are interlaced, yet you don't see it.

In regards to the field order, I just used whatever default that was selected... I didn't alter that setting in TMPGEnc Plus.

Depending on the method used to deinterlace the footage, you might have thrown away half your resolution by discarding one of the fields, or blended the two fields together using one of a couple of methdos. Eitherway you have ended up with a progressive movie.

Hmm, I'm not sure what deinterlacing method was used in TMPGEnc Plus: the software automatically chose "interlaced" as the video source and the only thing I altered was the source aspect ratio (from 4:3 NTSC to 16:9 NTSC) and changed the output from "interlaced" to "non-interlaced" with an aspect ratio of 16:9...

Is there any way of knowing that I've thrown away half of my resolution quantitatively? I don't readily see any degradation in the picture quality after I burned a new DVDRW for viewing.

Thanks again for all you help.