Quicktime occasional problem

bdg wrote on 5/13/2013, 1:44 PM

Just had another of what are only occasional V12b563 crashes.
These only happen when encoding in Quicktime (7.6.2) so I can use Handbrake to produce the final output for the web.
The crashes only occur at the 10% encoding spot in the video.
A warm boot always fixes things.

Now the interesting part :-)
This morning I noticed that the 10% encoding place was the point at which the preview window starts showing 0% of the video.
It's a bit odd but the QT codec does something none of the other codecs (that I use) do: Compress 0 to 100% of the preview in to between 10 and approx 75% of the whole encoding process. Prior to 10% and after approx 75% the preview shows only black.

Has anyone got any suggestions and/or are Sony actually doing anything about this crash? I keep sending the crash report to them.

Comments

musicvid10 wrote on 5/13/2013, 2:41 PM

Quicktime encoder uses the first 10% to prescan the output, the next 65% to encode, and the final 25% to write. There are a number of things QTFW doesn't always like -- anamorphic pixels and non-4 macroblocks, to name a couple.

Post the complete rendering details, and we may be able to help you figure out why the scan is failing. Are you writing to DNxHD or another codec?

robwood wrote on 5/13/2013, 4:25 PM

These only happen when encoding in Quicktime (7.6.2) so I can use Handbrake... -bdg

you could try encoding to AVI instead of MOV, if prepping for HandBrake.
i use lossless AVI, then encode in HB, then delete the AVI.

JHendrix2 wrote on 5/13/2013, 4:57 PM

thanks for the heads up, i just replicated this while considering moving to 12. for me it was with qt 7.73. back to 11...bugs bugs bugs

bdg wrote on 5/13/2013, 4:58 PM

Yes, DNxD. Everything as suggested in the "How to get the best encoding for..." Whatever.
It doesn't happen often which is why I haven't said anything before.

Oh boy, 2 scary big words: anamorphic, macroblocks.
I kinduv know what you're talking about with macroblocks because Handbrake does that. But how to find out what V12 does - or perhaps I have unknowing control over these two things in Vegas?

Alls I know about anamorphic is it's something to do with aspect ratio and what I like is the very wide screen look of Cinemascope so I am getting that look without having a clue as to what would be the best way to do it - in other words, by trial and error I have found these setting in V12 that give me an apparent Cinemascope aspect ratio:
I start with HD 1080-24p and then modify that with a PAR of 1.333 and end up with something that looks good to me both on BD and on the web.
Haveing done this I may well find myself face to face with an alternative copy of Red Dwarf, hopefully not the one with the really nasty, and really good versions of Rimmer, Lister, and the Cat. But I digress.

musicvid10 wrote on 5/13/2013, 8:06 PM

Post a screenshot of your render settings and the DNxHD template used, please. That's all I really need.

bdg wrote on 5/13/2013, 9:13 PM

Here it is:
http://dl.dropboxusercontent.com/u/167714824/QuicktimeSettings.jpg

musicvid10 wrote on 5/13/2013, 9:36 PM

Nothing wrong with your settings.

bdg wrote on 5/13/2013, 10:03 PM

Thanks.
I'm just testing uncompressed avi as an intermediary as suggested by Robwood.
One thing I like about it is I can set the audio to 24bits. (It's a good practice to carry all the bits you've got as far as possible down the line).
The mp4 produced by Handbrake from the avi certainly looks good and has slightly higher bit rates for both audio and video.
I guess I will do that in future as long as I have the disk space.

musicvid10 wrote on 5/13/2013, 10:06 PM

Well, AVI will work with later versions of libav in Handbrake, but keep your levels at RGB, and expect monstrous file sizes.