Interlaced vs. Non-Interlaced?
 

Just a quick question:

When encoding to MPEG2 (SVCD), which should be used? Interlaced or Non-Interlaced? What are the differences in the resulting MPEG? Any difference in size?

Thanks..

-gonzo

If your target is SVCD, you don't need to de-interlace. That's an advantage of SVCD over standard VCD. So if your source is interlaced, you just encode without any de-interlacing. If your source is progressive FILM, then you encode at 23.976fps with 3:2 pulldown enabled. This way you keep the original frame rate, and your SVCD will look better than if you encode at 29.97fps.

-kwag

I usually do an IVTC if it's Telecined before I encode it, thus encoding at a steady 23.976. My question is the differences between doing a Progressive encode (Non-Interlaced) vs. Interlaced encode for the actual target MPEG..

If, for example, my source is FILM (23.976), I should then encode at 23.976 with 3:2 pulldown enabled (thus making it 29.97)? Why not just encode at 23.976 Interlaced..?

Because for SVCD you must encode 23.976 and use 3:2 pulldown. SVCD doesn't support encoding directly at 23.976 without pulldown. VCD does.

-kwag

Well technically SVCD doesn't support any resolutions other than 480x480 either :) I've encoded many an SVCD directly at 23.976 with no problems with encoding or playback.

What we're creating here are X(S)VCD's, which are non-standard..

So what would be the technical drawbacks to encoding to Interlaced vs. Progressive, or vice-versa, or encoding to 23.976 w/ or w/out pulldown.. that's my question.. :?:

I've done a few tests, and the only differences I've found so far is a smaller size with Interlaced (though it looks like garbage), and a much larger file when doing 3:2 pulldown.

Interlaced material will be at 29.97fps, which is 20% more than progressive NTSC film. The only time I would say stick with interlaced is if you're encoding from a non-telecined source such as a TV cap.

A DVD player should be able to do the telecine internally if the correct flag is set in the SVCD header. At least, that's my understanding from other posts. I don't make SVCDs since my standalone won't play them :).

Ahh yes, this makes perfect sense. I didn't even think of that :roll:

Thanks!

-gonzo