[kman42]

I have some divx (.avi) movies that play fine in QT, but it takes forever move between parts of the movie when clicking on the slider. I've found that if I convert them to MP4, this problem is solved. The only difficulty is that to get the same quality I have been encoding at a bitrate of 1048, which basically doubles the size of the files. I've just been using the Export feature of QT6. Is there a better way to do this? Is there a way to calculate the appropriate bitrate so that I don't lose resolution, but don't make files twice the size?

thanks,
kman

[el chupacabra]

Your always going to lose quite a bit of quality when converting between the two because of the type encoding that mp4 and divx are. I wouldnt convert it to mp4. divx is superior in size and quality ratio by long shot. Theres no way you will keep the same quality when going from divx to mpeg4.

[mikerwpi]

You're always going to lose quality when encoding from one format to another. Since Divx and QT6 are both variations on MPEG4, the quality loss will be worse then normal. The high bitrate when you're going to QT6 doesn't compress the video as mush, which is why it looks good. Your best bet would be either capture directly to QT6, so you can get good quality at low bitrate, or try to rewrap you Divx as QT6.

As I said before, Divx and QT6 are both based on MPEG4. There might be a way, depending on how the DIVX was originally encoded, to convert it to QT6 without reencoding. Here are some instructions on how to do it on a PC: http://www.divx.net.nz/guides/isomp4/