Moho Forum

I read this thread in trying to answer if it was necessary to save png format photos as interlace, for animation and then later export as avi for for editing into a dvd for TV (PAL). The answer seems to be "don't use interlace images intially, the video edit software will do that when required" - BUT THEN I GOT TO THINKING.

If I produce a 25 fps AnimeStudio animation (i.e. a match for PAL later on), will my video edit software produce optimum interlace images for fast moving action - i.e. will each field be time shifted and different or will they be identical and so not give smooth movement. Seems to me that to be different the editing software would have to do some sort of calculation based on the 25 fps whole frame input OR does it mean that the AS animation should be done at 50 fps so that each of the fields for the interlace output are at different times OR does Anime Studio already do this sort of calculation and "render" when exporting to avi. I know (?) the "i" in avi is for interlaced but am thinking that this a reference to the way the audio is integrated with the image and not to the actual image part - though in my video camera (and I think most) the image is interlaced.

As a matter of interest I've just spent a long time to work out that my video editing/processing procedure was swapping the fields around (still don't know where exactly) and making the output very jerky where the image moves fast - instead of looking at the four fields in two frames as 1,2,3,4 the result was 1,3,2,4 and very nasty. For the record I use Pinnacle Studio, but I am guessing that most consumer video edit software will use the same approach.

Any helpful insight into this issue would be appreciated. I'd rather not have to take the time to do yet another test !!

Hey Trevor, just to check, you might try exporting the animation to Quicktime. Since this is the internal AS player, it should help eliminate the codec as a culprit of this 'jerkiness'.

Thanks synthsin75 for the advice, pretty obvious I gues but not so much to me as it was outside my square...but in case of confusion....my last para about a "jerky image" as an aside largely outside more to do with video procecessing and I assume you are commenting as a quick test for my the "what is optimum" first part of my post.

Trevor

I'm not sure what would be optimum, but interlacing shouldn't effect motion smoothness. That's why I thought of the codec. I would think that you'd only want to interlace the final output from your video editor. AVI uncompressed deinterlaced, I think is how you'd want to output from AS.

But don't quote me on that.

My thinking is that if interlaced avi is 25 frames per second in 50 fields per second (is that correct thinking), then if the input is 25 images per second rather than continuous (as in real life) then you will get 25 pairs of images as output and therefore a subtely jerky image (unless half the fields are synthetically generated), rather than 50 unique images and a smoother apparent output.

The critical thing to remember in any image that has been divided, is that it needs to be reassembled again. Due to the inherent problems of electronics, errors will always take place, creating artifacts. The current advice from the HD mentors is go with progressive where ever possible as this will give the best quality. The broadcast aim is to get to 1080p60 eventually, when the delivery systems permit. The guys at NHK actually want to get to UHDTV 60, that is 7680 * 4320 progressive 60 fps (with 22 channels of audio ) - they reckon it might be 10 years before they have the system operational, though it has been screened live in Japan already.

Unfortunately, although AS can render a frame this big (I have already tried), the colour depth is insufficient - it will require 24 bit t prevent the graduated areas banding.

The other advantage of 24p is that it is a perfect multiple for 3:2 pull-down (the frame doubling technique used to get 24 fps to 60). This produces a better/smoother standards conversion.

If people really need to have interlace, animate and render at 60 frames per second (to png stills), then import into a program like debabaliser, Combustion etc, and re-interlace the frames into fields. It does provide a very good result. It also provides the option to render odd or even interlaced video - depending on if you are rendering to DV or to another video format.

Rhoel