Cineform NeoScene Settings Inquiry

IAM4UK wrote on 7/10/2010, 8:48 AM
I use CineForm NeoScene to transform AVCHD (from Canon Vixia HF S100) and MOV (from Canon EOS 7d) to intermediate AVI for editing in Vegas Pro 9.0e-64.

The manual in .PDF for NeoScene appears to be outdated, and the CineForm website yielded no answers, so I'm inquiring here:

Within the "Preferences" dialog box for converting files, under the subsection "CineForm Encoder Options," what is the purpose and effect of the option "I-frames only?" It appears to have replaced the manual-referenced item: "Enable Smart Rendering: This feature is for Sony Vegas users who want faster exports at the expense of larger file sizes. Select this option only if it fits your needs." I have the I-frames only box checked, and my results do seem fine, but I'd like to understand it.

Comments

IAM4UK wrote on 7/10/2010, 11:05 AM
Thanks for the info on I P and B frames, musicvid.

In the context of NeoScene's preferences, then, I assume selecting "I-frames only" does not result in any frames being skipped; rather, it limits the recompression to using no P-frames nor B-frames. Right?
musicvid10 wrote on 7/10/2010, 2:32 PM
" I-frames Only " means every frame is coded in and of itself; no lookahead or lookbehind.
jabloomf1230 wrote on 7/12/2010, 4:55 PM
The official Cineform message board is here:

http://www.dvinfo.net/forum/cineform-software-showcase/

That might help you, in the future.
kkolbo wrote on 7/12/2010, 5:34 PM

Thankfully David from Cineform stops by here occasionally. Not everyone can get on DVInfo.net . I for one was denied membership and to this day I have no idea why. Inquiries have never been answered.

David Newman wrote on 7/13/2010, 7:22 PM
We switched the terminology from "Smart Render" to the more technically correct "I-frame only" after more than just Vegas users needed the feature. Originally CineForm employed a weird (and cool) 3D pyramid like wavelet that compressed two frames at once for 20+% more compression without a quality loss. But not all video tools work that way. The most widely compatible format is each frame is stored on it own, an I-frame or Intra-frame compression. That is what this option selects.