DV Lower Field First - can be rendered as progressive scan ?

[tarrickb]

Hello all.

I have interlaced DV footage that has "lower field first" order. I want to render these videos (after editing) to DV to use with On2's flash encoder. I have been playing with FLV encoding settings and noticed that there is a HUGE difference in quality when I tell On2 to de-interlace vs. keep source interlaced (quality is much better when kept interlaced, but interlaced lines are apparent as video is being viewed on the web).

I realize that if I don't want On2 to do the de-interlacing I should do it myself, and was looking around Sony Vegas 8.0's DV render screen and noticed that I could set the field order to none (progressive scan). The resulting file looks to be progressive when displayed in VLC (without de-interlacing playback filters) and giving it to my On2's FLV encoder as progressive FLV looks better and is without the interlacing lines.

I just wanted to check if this is the best method for transforming my interlaced DV into a progressive video (I don't know what rendering without a field order really does!). Would I be better rendering the DV video with the same settings as my source and de-interlacing via a VirtualDub filter after?

Attached is a photo with the Sony Vegas 8.0 DV render settings I mentioned.

Thanks.

[Soopafresh]

Setting it to progressive must throw away 1 of the 2 fields which comprise the picture. That's how most "dumb" deinterlacing works. It's a crude, but effective way to get rid of the interlaced lines. Probably the fastest method there is. Smart Deinterlacers will be somewhat slower, but the output will be higher quality. That'll take a bit more work, however, as you'll have to use an app like AVIdemux, Avisynth, or VirtualDub with the appropriate deinterlacing plugin.

Hard to cover it in one post, I'm afraid. It's a largely debated issue as far as which method is "best" or highest quality.

[tarrickb]

Thank you for the reply. I think for my purposes, using Vegas to output a progressive file using the crude de-interlacing method may suffice as the flash video is being reduced to 480x360 and at this size it is hard to notice any differences between Sony de-interlacing and a Smart de-interlacing filter run in VirtualDub.

So my understanding is that rendering progressive scan simply throws away one field (and effectively reduces my framerate by half)?

Thanks,
TB.