Record iFrame at 720p

Well it would appear that turning this on makes your videos record at a much higher datarate, and I assume iframe only.

What this means is when recording video within iMovie you will have video about 3x larger then it normally shoots.

I'm getting around 36.20 Mbits/s

Better quailty, but takes much more space.

A bit more playing came up with some interesting notes.

You have to record in the iMovie app to acheive the new iFrame high datarate feature.

If you export the recorded video / timeline to your camera roll it compresses it back to the standard lower datarate video.

But if you want to get a hold of the high datarate video then export project to iTunes.

Change the extension to .zip

Uncompress, and there you have the high datarate video, i Frame, ready to edit.

It should be much better quailty and easier to edit, as it has either more or only i Frames.

http://en.wikipedia.org/wiki/Video_compression_picture_types

As I was playing with the same question in another thread 🙂...

You can also export to iTunes, and open in tht file directly in iMovie, but only (I'm guessing) if you have the latest version of iMovie. If you've got a recent computer, it would have come on it. Otherwise, it's a $14.99 purchase form the App Store.

Except that the native 1080p that the 4s and 5 have is better quality. This setting is used to make smaller files that can be edited faster on mobile devices. But I could be wrong.

It actually makes LARGER files. :) You are correct, though, in that it makes the files easier to handle as every frame is a stand-alone i-frame. This means less computation required for playback and you can edit the captured video without waiting for a lengthy transcode process.

This article from Apple says that the file sizes are smaller. Hmmm.

http://support.apple.com/kb/HT3905

From that page:

"Setting a camera or camcorder to record in the iFrame format will result in optimized performance in iMovie ’09, iMovie ’11, and Final Cut Pro 7 or later. With iFrame, content is kept in its native recorded format, so importing and editing video is fast, and file sizes are small."

The file sizes ARE small compared to uncompressed, but, in my tests, capturing in 1080p NON-iFrame gives smaller files than iFrame.