Sorry. IVTC stands for Inverse Telecine. When film is transferred to video it is Telecined which is a process where duplicate frames are added. Film is 24 frames per second and NTSC TV is 29.97 frames per second. Frames have to be added to the film for them to play smoothly on an NTSC TV. IVTC takes those duplicate frames out and changes the framerate back to that of film. The advantage of this is that the picture will look good on both a TV and PC monitor.

Okay. IVTC has a couple of other advantages. It is easier to resize a file that has been IVTC'ed. This is especially important if you are converting a 4:3 source to 16:9. If you don't do an IVTC, you'll probably end up with a messy video with combing artifacts. The other big advantage is that you can allocate more bitrate to your video quality. Bitrate is applied per second instead of per frame. So, you can have more bitrate if you have 23.97 fps instead of 29.97. I say 23.97 because that is what it really is. Some just round the number up to 24 fps.

I hope this makes sense. It get more complicated if you are talking about mixed sources that have Telecined and Interlaced parts. IVTC should only be performed on Telecined sources and not Interlaced sources. That is why I didn't do IVTC on the Star Wars extras DVD I made. I also didn't resize it to 16:9 because the interviews themselves were full frame, so I didn't have any black bars to crop.

Sorry to get off on a tagent, but I hope this basic explanation helps.

Patrick