Problem: Doubled/overwritten frames in composition

[Steve Roberts]

Check the project timebase in the project settings. Does it match your comp frame rate?

[Greenlighted]

Err, do you mean the project’s timecode base (for Display Style) or are we missing something here? In any case, here’s how it looks:

Project – Timecode Base: 25 fps
Composition – Frame Rate: 25
Source – Frame Rate: Use frame rate from file (25,000 fps)

[Steve Roberts]

Hmph. That looks right. (sorry, I meant timecode base) It seems as if you’ve tested properly, by creating the comp from the footage.

Have you tried interpreting the footage with no field separation?
What is the codec of the footage?
Have you tried trashing your preferences?

[Greenlighted]

[Steve Roberts] “Hmph. That looks right. (sorry, I meant timecode base)

No worries. Sorry for asking a nitpicky question, but this problem is really beginning to get to us so we were actually hoping that there was some kind of setting we didn’t know about…

It seems as if you’ve tested properly, by creating the comp from the footage.

Something we’ve noticed is that the doubled/overwritten frames’ positions (as well as the amount of them) change depending on where in the source the clip starts. That’s probably a clue to what’s going on, but we’ve been unable to make something out of it.

Have you tried interpreting the footage with no field separation?

Yeah, same behaviour. (But, of course, with the “interlace lines” visible.)

What is the codec of the footage?

DV AVI. (Think it’s type 2, if that can make any difference.)

Have you tried trashing your preferences?

Probably not. I’m not even sure what you mean by this. (We have however created a completely new project and just done this test, but still with the same results.)

Thanks for trying to help out. Really appreciate it.

[Steve Roberts]

Here’s some pref info from Mark Harvey:

The preference file is in a hidden folder on a PC, you have to activate hidden folder view (tools-folder options-view-show hidden folder)
The preferences are located in C-documents and settings-your username-application data-Adobe-After Effects(will be accompanied by a version number)
Delete the After Effects folder. Once you have a good set of preferences, simply copy the After Effects folder that I described above to another location on your PC…..that way when After Effects starts to act a little crazy, you can just bring that folder back in to replace the corrupted one, without losing templates etc.

You wrote “where in the source the clip starts”, yes? Do you mean “where in the comp”? If not, could you please clarify? It does sound like a clue.
And the source clip really is 25 fps?
Is it telecine’ed film?
And is it source from a camera, or from somewhere else?

[Greenlighted]

“Here’s some pref info from Mark Harvey:
[Pref info deleted]

Interesting. Tried it, no difference.

You wrote “where in the source the clip starts”, yes? Do you mean “where in the comp”? If not, could you please clarify? It does sound like a clue.

Where the in point in the source clip is affects where the frame problem occurs. While verifying/testing the problem the clip was placed at the beginning of the comp. When we moved the in point, and relocated the clip to start at the beginning of the comp, the affected source frame(s) changed. (Also, see more updated test results below.)

And the source clip really is 25 fps? Is it telecine’ed film? And is it source from a camera, or from somewhere else?

Should be 25 fps: taken from a PAL camera (Canon XM-2, DV), recorded directly to hard drive.

More testing, more clues:

New project, imported footage, interpreted footage, created comp from footage, RAM previewed: 3 doubled frames in a 5 second workspace.

Without altering anything in comp, did Edit->Purge->All and RAM previewed: 2 doubled frames in different positions!

(An additional full render through the render queue resulted in yet another variation in doubled frames.)

Almost seems like it ignores rendering certain frames and instead uses the previously rendered one. Does that make any sense? Futhermore, it uses OpenGL (NVIDIA GeForce FX 5200) where it can, could that perhaps affect anything?

Sigh. Just guessing wildly here (due to desperation)…

Again, thanks for helping.

[Steve Roberts]

Did you try switching off OpenGL in AE altogether?

Hail Mary attempt: try the Secret Prefs (hold down shift when accessing edit>preferences>general, and don’t release it until you see the big dialog box) and set it to purge every 5 frames (or less for now).

[Greenlighted]

Tried both, no (positive) effect. In fact, it kinda felt like the problem increased (more doubled frames) when the frame purge was set.

[Steve Roberts]

Now for the hard solution: have you tried pulling out RAM chips?

[Roman Flute]

How did you record it straight to hard disk?

Have you tried to open the footage in another package – maybe an editing package?

I think your cam is the GL2 (NTSC version) – which I have – so I usually come in firewire off of tape. But was wondering about the aquisition…

I have experienced exactly what you are describing with MPEG2 files. Mainly – because true MPEG2 streams are not individual frames- but averages. I have found that AE sometimes flakes out on those. It gets worse if you start mid stream – more errors. So I just want to make sure you actually got a DV stream rather than an MPEG2 stream.

For instance – one work around – my Final Cut box does not have the issue with those files. So I run it through there and then move it over to my PC for use in AE. Haven’t ever tried Premiere ( if this is your issue… ) – but you might look there – and see if another app has the issue. If not – re-render out from that app and test… It might solve your problem for the time being even if it is a DV file.

Hope you find the solution…

RF