Horizontal lines when converting from DV to DVD

[pacman99]

Hi,

I've been trying to convert some content from my digital8 camcorder to DVD through firewire. I had no problems capturing it into DV format but when I go to convert the DV file to MPEG2 using either TMPGENC or Procoder, I encounter horizontal lines in the picture. I tried to play the resulting mpeg2 file on my DVD player. I thought the lines woudl go away but they don't. I keep seeing horizontal lines in the picture.
De-interlacing filters don't work either.

I recorded the source in 16:9 mode on my Sony D8 camcorder and i transferred it over to my computer using a firewire connection and DV capture software included in Sony Vegas 5. The DV file itself is also MUCH more brighter than the resulting MPEG2 file. I've been trying to encode the file at 7MB VBR.
I've tried to convert the DV file to MPEG2 by setting the source as both 4:3 and 16:9, trying to convert it down to 23.97fps, 24fps, (using inverse 3:2 pulldown), tried noise reduction filters, deinterlacing filters in all three modes, tried changing the field order from BOTTOM TO TOP to TOP TO BOTTOM. I've had no luck
Another thing, i've tried to encode the mpeg2 file as both interlaced and progressive.

Is there something i'm doing wrong?

Thanks~

[Guest]

Usually this is a result of doing vertical resizing before deinterlacing. You must deinterlace first.

If that is not your problem, please post a screen grab so we can see what the lines look like.

[pacman99]

I haven't been resizing the video at all. The captured DV is in 720x480 and the output MPEG2 is 720x480 as well. I'm attaching an image of what the "horizontal" lines look like. This is pretty much how it looks on my standalone dvd player as well.

[scharfis_brain]

uhm. this looks like a heavily zoomed image.

how did you made that image?

please use either
the screenshot funtion of your Software-DVD-Player
or
load the mpeg to virtualdubmod, scroll to the desired frame, press STRG+1
then open M$-Paint to paste and save it.

[jggimi]

You may also want to take a screenshot of the same frame from the DV .avi file, so that we can compare pre-encoded and encoded frames.

[pacman99]

yes you're right. I did zoom it in so the horizontal lines would be more apparent.
Okay, posting unedited images of both the DV source and the resulting MPEG2. The reason why I didn't post the DV source in the first place was that it's interlaced so it doesn't look that great on the PC anyways ^_^;;
Both taken using VirtualDubMod.

DV Source:


Resulting MPEG2:

[bb]

First of all: is it just me? I can see many vertical lines - not horizontal ones...

This is really weird. Which codec do you use? Did you use digital zoom (probably not)?

Could be a colourspace problem

bb

[Guest]

I see vertical lines, but they are there in your source material.

These broadcasts of Indian films, etc., are usually very poor quality.

Please clarify the symptom you are describing. Have you confused horizontal with vertical?

[jggimi]

I've run the original image through SeparateFields(), and then zoomed in. I can see the vertical lines in the individual fields.

[pacman99]

maybe i'm not using the right terminology. Sorry about that. First of all, this isn't an indian broadcast. It's actually material I took with my Sony D8 camcorder It was my cousin's wedding.

The only modification that I made was that I recorded the content under the 16:9 aspect ratio on my D8 camcorder. That's it. No other modifications.

I'm an idiot. Yes, I meant VERTICAL lines. Up and down They don't go away even on my standalone DVD Player.

Didn't use digital zoom, no. I might have in some scenes but i'm 99% sure it wasn't used in this scene. [Digital Zoom from the camera itself]

Anyways, so how would I get rid of these vertical lines? I used to think my TV would handle it on its own. It's a HDTV widescreen TV. If i try viewing the video in 4x3 mode on the TV, the vertical lines aren't that apparent, but still there. I am encoding as source = 16x9 and output dvd = 16x9 aspect ratio as well. The input, as I already mentioned, was 16x9 as taken by my camcorder.

[Guest]

OK, it's an illusion. They only occur when you zoom and they are just simple zoom aliasing.

Look again at the source DV frame. There is nothing wrong with it.

[pacman99]

I don't mind how it looks on my computer. It's just when I watch it on my TV, I see the same lines. (I'm talking about the MPEG2 encoded DVD) My TV IS stretching the image to Panoramic view but that shouldn't matter since the DVD is encoded in 16x9 mode anyways.

[scharfis_brain]

please connect your D8-Camcorder directly to your TV using the S-Video (black Hosiden Plug) or Composite (yellow Chinch) Cable.

then report whether the steppyness is gone or not.

[Mug Funky]

hmm. unfortunately it seems a large number of camcorders take frames at half-horizontal res, and resize it back to 720 for recording onto DV.

if you're up for using avisynth, you can mitigate this effect by:

horizontalreduceby2().lanczosresize(720,last.height)

this will also make the source look a tad blurry, but bear in mind that no detail is actually being lost (not counting small losses from the upsizing), and the source really is that blurry under the aliasing. the plus is you'll get better quality mpeg-2 for the same bitrate as there's less apparent detail to compress.

you're probably noticing this effect more because of the bright lighting and very bright colours. i first noticed it after shooting a guy in a very bad superhero outfit under 500 watts of tungsten, because before that the contrast just wasn't high enough to see it.

i am however surprised that you see this on your TV... it must be a very good one to show that much detail (usually the artefacts are blurred away).

[pacman99]

thx i'll try it I'm surprised my tv shows it too...It's actually a bad thing in this case heh.

[pacman99]

okay. Thanks to Mug Funky, I don't see the vertical lines anymore! But...now that caused a NEW problem It's hard to show it in a snapshot because you need to see it on the TV. If you look at the screenshot right now, in the chest area of the woman (where she's wearing the jewellery), there's a weird jittering effect I guess where the colour alternates. (sort of like the picture on an old vhs tape that's been sitting for a while).

How can i fix this? Does this have to do w/ the 4:2:2 colourspace problem w/ NTSC DV sources or can I just fix this by trying some other settings?

Thanks~