JohnMK
14th October 2002, 11:23
Hi there,
I'm trying to encode Carl Sagan's Cosmos DVD's and running into a bit of trouble. It's hybrid material, usually about 60-70% NTSC, 30-40% FILM. Obviously, there are problems with leaving it at 29.97fps, and forcing it to 23.976fps. I think leaving it at 29.97fps is the best solution, but which parameters to use -- that's another one altogether.
I'm familiar with one solution:
Telecide() <aside, should I use guide=1 here?, in a hybrid clip too?>
Decimate(mode=1)
The problem with this is that it spits out a lot of duplicate frames, resulting in jerky panning scenes. Decimate(mode=1) tries to fix that by making it an interpolation of its surrounding frames, so that fluidity of movement is preserved. In practice though it doesn't seem to improve things to a tolerable level, so I'm craving another way to go about things. In doing so I just thought to myself, what if we don't create duplicate frames to begin with? What if we just use FieldDeinterlace() and leave out Telecide() and Decimate()? What are the advantages and disadvantages of this. This is my guess, I may very well be wrong:
1) Movement fluidity is preserved as it was in original source.
2) Image quality reduced, however, because the original 24fps material isn't recovered to independent frames, so we get some blurriness.
Give the choice, I'd rather live with 2) than 1).
Please let me know if I'm right, or wrong, or whatever, or if you might have either a solution for me, or just bad news that.
I'm trying to encode Carl Sagan's Cosmos DVD's and running into a bit of trouble. It's hybrid material, usually about 60-70% NTSC, 30-40% FILM. Obviously, there are problems with leaving it at 29.97fps, and forcing it to 23.976fps. I think leaving it at 29.97fps is the best solution, but which parameters to use -- that's another one altogether.
I'm familiar with one solution:
Telecide() <aside, should I use guide=1 here?, in a hybrid clip too?>
Decimate(mode=1)
The problem with this is that it spits out a lot of duplicate frames, resulting in jerky panning scenes. Decimate(mode=1) tries to fix that by making it an interpolation of its surrounding frames, so that fluidity of movement is preserved. In practice though it doesn't seem to improve things to a tolerable level, so I'm craving another way to go about things. In doing so I just thought to myself, what if we don't create duplicate frames to begin with? What if we just use FieldDeinterlace() and leave out Telecide() and Decimate()? What are the advantages and disadvantages of this. This is my guess, I may very well be wrong:
1) Movement fluidity is preserved as it was in original source.
2) Image quality reduced, however, because the original 24fps material isn't recovered to independent frames, so we get some blurriness.
Give the choice, I'd rather live with 2) than 1).
Please let me know if I'm right, or wrong, or whatever, or if you might have either a solution for me, or just bad news that.