I recently got a new mini DV camcorder and when i upload the uncompressed video to my computer (using an ieee 1394 card and premiere) it looks perfect. But then as soon as i try to compress it to mpg or any other format for that matter eg. Divx, Xvid, horizontal distortion appeare all over the footage. Now i've compressed and decompressed footage countless time using premiere, virtual dub, TMPEGc, etc. I have even worked with uncompressed footage from anolog sources but this is the first time i acctually work with the DV standard. Could anybody explain what is going on with the horizontal distortion and what i can do to solve this issue?
Thanx.
Life is the art of making movies without editing
Life is the art of making movies without editing
Sounds like interlacing artifacts. Deinterlace the video before you compress it to mpeg and it should look fine.
quote:
Originally posted by MarkG
Sounds like interlacing artifacts. Deinterlace the video before you compress it to mpeg and it should look fine.
Hi MarkG,
what is the interlacing method? When I nust to use it?
Thank you so much,
rafano
Basically both NTSC and PAL split the picture into two fields, which are recorded and displayed on alternate lines of the screen. The second field is recorded 1/60 of a second later than the first on NTSC and 1/50 later on PAL, so if there's movement in the frame you'll see that alternate lines are displaced from each other, and on a computer monitor that will look like there are lines across your frame.
Deinterlacing basically removes one field and guesses what should really have been on those lines if the entire frame had been shot in one instant rather than two instants a fraction of a second apart. Simplistic deinterlacing just averages the pixels on the line above and below, while more complex software will try to figure out which parts of the frame are stationary and only remove motion artifacts, to give a better picture.
