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payton
04-03-2006, 10:22 AM
hi,
im using time remapping with hold keyframes for some already animated layers.
but there is one problem. the counting of the images starts everytime with "1" , not "0". these names are used everywhere in the production pipeline.

but when im using time remapping in AE the frame counter starts with "0" (sometimes it starts with 1, but i dont know why). thats a problem because i have to manually write down the already written dopesheet into AE.

so my question is: how can i force time remapping to start counting with 1.

thanks in advance...

payton

Mylenium
04-03-2006, 04:42 PM
hi,
im using time remapping with hold keyframes for some already animated layers.
but there is one problem. the counting of the images starts everytime with "1" , not "0". these names are used everywhere in the production pipeline.

but when im using time remapping in AE the frame counter starts with "0" (sometimes it starts with 1, but i dont know why). thats a problem because i have to manually write down the already written dopesheet into AE.

so my question is: how can i force time remapping to start counting with 1.

thanks in advance...

payton

Time Remapping uses rounded frame numbers - since there cannot be "half" frames (remember, all of AEs calculations are based on time, not framecount), it either rounds them up or down to comply to full frames, resulting in the odd 0/1 behavior. There isn't really anything you can do about it, even pre-composing won't help you since it suffers from the same phenomenon. Depending on the type of stuff you are working on you might try to increase the composition framerate to get a more predictable behavior, but it may not be practical for what you are doing.

Mylenium

scrimski
04-03-2006, 04:56 PM
remember, all of AEs calculations are based on time, not framecount

You mean like an absolute timer and then the animations and so on are calculated back analogue to the framerate? Could you describe it a bit further(so, dass es ein 4-jähriger versteht)?

Mylenium
04-03-2006, 05:57 PM
You mean like an absolute timer and then the animations and so on are calculated back analogue to the framerate? Could you describe it a bit further(so, dass es ein 4-jähriger versteht)?

Basically yes. AE will sample data corresponding to the current time that is used in the composition. If it wasn't, things from basic footage interpretation to interlaced footage to nested compositions with different frame rates and last but not least time remapping weren't possible. So in technical terms, a 25 fps clip in a 25 fps comp just happens to have each frame coincide with a timeslice, but it's not the given. Conversely it can mean that a time remapped sequence can have two frames within the same timeslice, forcing AE to mix both - a procedure known as frameblending. Ultimately that's what it always boils down to: AE will dynamically divide a second by the frame rate and look at the state of the buffers within the timeslice. It does not care if the effects, footage or whatever have their own temporal relations.

Mylenium

payton
04-03-2006, 06:19 PM
thankx mylenium. seems you know really everything about AE. amazing!

i understand what you said, but what i dont understand is that AE sometimes starts with 0 and sometime with 1. in both cases the comp is 24fps and the footage is interpreted as 24fps. maybe i will know exactly what AE is doing und the hood after finishing this project ;)

Mylenium
04-03-2006, 06:35 PM
thankx mylenium. seems you know really everything about AE. amazing!

Well, thanks for the compliment, but I don't think so. There's enough to learn still. Maybe because I have been in contact with some developers and also have an active interest in some of the underlying math/ code I sometimes incidentally know a few things, but that's all.


i understand what you said, but what i dont understand is that AE sometimes starts with 0 and sometime with 1. in both cases the comp is 24fps and the footage is interpreted as 24fps. maybe i will know exactly what AE is doing und the hood after finishing this project ;)



Well, if you time-remap them it's quite possible one of your keyframes is in a non-ideal position, forcing the others to conform to this one key and making them snap to seemingly wrong frame counts (for instance Bèzier interpolation could do this). So in a 24 fps comp if your first key is pulled beyond a time of 0.41667, it will be frame 1, if it's below this value it will be frame 0.

I agree that all this is very therotical and does not seem logical at all, but you will get used to it eventually ;).

Mylenium

payton
04-03-2006, 08:35 PM
well, i understood the math, but not AE.
im working with hold keyframes (no interpolation) and AE does with same comps and footage interpretation different things. ok, i know there has to be a difference that causes this. but its not to obvious.

maybe it has something to do with the fact what im doing first. i think it works only when i interpret the footage first and then drag it to my comp. had some similar problems with creating proxys for footage that i reinterpreted after dragging into the comp. i will check that tomorrow...

thx,
payton

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