Reducing ant crawl on still image pan & zoom

eightyeightkeys wrote on 12/22/2009, 7:19 AM
I've had this issue for quite some time, but, after viewing last night's rendering, I have got to get this sorted out.

Details :
Video shot in HD on an HV30
Still Images shot in high resolution on a Canon 3.1MP digital camera
Captured in VMS
Edited in VMS

Rendered in VMS :
720 X 480 SD in "Best Quality"
Frame Rate -29.97
Field Order - Upper Field First
Video Format - NTSC
Interleave Every Second - Checked
Interleave Every Frame - Checked
Audio rendered as PCM 48kHz, 16bit

DVD Authoring in DVD-Architect :
Reduce Interlace Flicker - ON
DVD A still requires compression of Video after VMS render !

I'm puzzled that DVDArchit. still requires further compression of the video, but, even so, the pan and zoom of still images has a considerable amount of ant crawl. It's quite distracting on my HD TV (showing in proper 4:3 STD Def)

What am I missing ? There must be a setting or three that I have wrong that is contributing to a very low quality pan and zoom result.

Comments

MSmart wrote on 12/22/2009, 11:01 AM
what did you render to in VMS, mpeg or dv-avi? How long is your video?
eightyeightkeys wrote on 12/22/2009, 11:34 AM
The videos vary in length from 3min up to 7 or 8 minutes. Does this have an effect ?

I rendered as "Video for windows-avi"
NTSC-DV
MSmart wrote on 12/22/2009, 2:42 PM
I tried to read up on the HV30 and see it's a MiniDV cam so the captured video is AVI, correct? If so, to clarify, when rendering are you using the NTSC DV, not NTSC DV Widescreen? Why convert 16:9 video to 4:3? Use the widescreen format.

DVDAS has to encode the video to mpeg format for DVD.
eightyeightkeys wrote on 12/22/2009, 3:02 PM
The HV30 shots are fine. No prob's there at all.

I'm going to 4:3 because my in-laws still have a regular TV and we're showing some vacation videos over Christmas. So, with VMS and DVDArch we can render to any "necessary" format.

But, anyway, curiously, it's the still images that have the crawl, and, only on pan and zoom. If there is grass, or, any finer texture, the playback is just not good at all.
Tim L wrote on 12/22/2009, 3:26 PM
On each still image, right-click on the photo on the timeline and select "Switches >> Reduce Interlace Flicker" (or rather, make sure that option is ticked). This will add some line-to-line filtering to the photo and will help get rid of the kinds of sparkles and line twitter you see when zooming or panning a high resolution photo.

Also, it will slow down your rendering quite a bit but make sure you set your render properties to "Best" (I see you already have done this). This uses a more sophisticated (but much slower) algorithm when anything is being resized and resampled.

In addition sometimes you get best results visually by resampling high-res photos down to a lower resolution *before* bringing them into Vegas. For a std def project, resize to something like 1200x800 or so, depending on how much you are going to zoom on them. (Maintain the pixel ratio your photos already have, but get the vertical resolution somewhere in the 800-1000 pixel range).

I think the "reduce interlace flicker" you have mentioned in DVD Arch Studio might only apply to the menus created in DVD Arch -- probably not to the video (but that I don't know for sure).

Tim L
MSmart wrote on 12/22/2009, 5:49 PM
got it. pics only, then Tim L's suggestion should be what you need.
eightyeightkeys wrote on 12/26/2009, 3:00 PM
Tim, that is an excellent tip !
Many thanks.
Dave

Oh, Tim....can this be applied to an entire track ? There are "Switches" but, not the "Reduced Interlace Flicker" option at the track level.
musicvid10 wrote on 12/26/2009, 4:34 PM
You should be able to copy one event, select the other events on the track, and "Paste Event Attributes."
eightyeightkeys wrote on 12/26/2009, 5:22 PM
Hello again musicvid !

Yes, I did do that, but, if the entire project could benefit from the "Reduce Interlace Flicker" switch, I wonder if there is a Global Switch/Function for this ?
Tim L wrote on 12/26/2009, 9:02 PM
You don't want to apply the "Reduce Interlace Flicker" (RIF) to video that is already interlaced and will be displayed as interlaced. The RIF somewhat blends or filters the adjacent scanlines of the image to reduce fine details (I'm not sure exactly what) so if you do this to interlaced video it ends up softening the details in the video and also kind of merging the odd and even video fields together.

I've done this by accident (applied RIF to video) and you end up with a kind of blurred video with very unnatural motion. Hard to describe, but it definitely looked "wrong". You effectively are taking two images that were exposed 1/60th of a second apart and blending those images together somewhat. Try it and see.

Tim L

PS: But it would be really nice if there was a preference somewhere to automatically apply RIF to all still images by default.