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norlight
02-16-2007, 04:42 AM
Anybody else have this problem?

Its quit reproducable as it happens 100% of the time...

No, its not my final output format as I usually then render to png-seq.

However, Ive missed the convenience of rendering qt-previews either for myself or client review located at internet distance. Yes, there are other codecs which will have to do in the meantime, but H264 is the future!

The moment I hit OK after having specified H264 LW BAM!... - Crashes:devil:

This happens only to LW.

I.e. Combustion, same machine, heck its even the same user account!, renders beatifully to H264.

So I conclude this is a LW thing. :thumbsdow

Any thoughts/similar experiences?

Lightwolf
02-16-2007, 04:51 AM
It could be that the codec tries to access frames other than the currently rendered one from LW.
While this is easy to retrieve in a compositing app, in LW it would mean a re-render of the required frame.
Just a hunch though...

Cheers,
Mike

norlight
02-16-2007, 05:08 AM
Thanks for very swift reply lightwolf!

Over time Ive seen your posts are always valid, and you might very well be on target here also, but to me what youre saying here is plain Greek!

Well Im not from that part of Europe, nice for vacation though...

Are we at an EXTREEEEEEMELY deep computer-science level here in which case perhaps chilton should be called for, or is there something I actually can do to fix this?:help:

Lightwolf
02-16-2007, 05:45 AM
Over time Ive seen your posts are always valid, and you might very well be on target here also, but to me what youre saying here is plain Greek!

Panikos would be the guy to ask for a greek answer, or Greg ;)

Allright, here is what I'm thinking:
H264 needs to know about the frames around the current one to encode decently. I.e. if encoding frame x, it needs to look at x-1 as well as x+1 (the previous and the next frame).
So it asks the app (LW): please give me the previous and the next frame.
LW can't do that, because those don't exist anymore (LW works with one frame at a time) or not yet (because the next frame hasn't been rendered).

*boom*

For a compositing app, designed to work with sequences of final frames, this might be easier to do.

(Again, I'm just guessing, I might be completely off base here. Also, animation saving in LW works a bit different from the above explanation).


... or is there something I actually can do to fix this?:help:
Hm, get QT pro, render to a single frame file format (TGA, PNG), convert them using QT Pro.

Cheers,
Mike

norlight
02-16-2007, 06:26 AM
Ok lightwolf, I know see what youre thinking.

Only thing is, other apps (ie Combustion) fixes the possible lack of a starting I-frame just fine. What C does, I dont know for sure but Im guessing it just simply makes the first frame an I-frame and then make the mpg stream from there.

The workflow to go via img seq is what I use for finals, but for quick previews etc it wouldve been so handy to render directly to intended format.

Granted, there are bigger problems in life, but its listed as an option so it should work!

norlight
02-16-2007, 06:28 AM
By the way lightwolf,

can you make a test-render to H264 and see how your system responds?

Lightwolf
02-16-2007, 06:46 AM
By the way lightwolf,

can you make a test-render to H264 and see how your system responds?
Sure I just did (9.0 only).
If I unset the keyframes in the QT options (i.e. no keyframes) it works, if I set the number of keyframes it crashes.
Windows 32, latest QT.

This was only a short 60 frame test.

Cheers,
Mike

Lightwolf
02-16-2007, 06:47 AM
Ok lightwolf, I know see what youre thinking.

You do?

You know more than I do then ;)

cheers,
Mike

John the Geek
02-16-2007, 07:21 AM
I'm with Lightwolf. I'd go ahead and buy QuickTime Pro for the $30 it costs and save a lot of trouble. Render out frame sequence in PNG, then open them in QuickTime as a movie (File > Open Image Sequence...), then Export your h264 there.

I agree though, it should get fixed in LW too...