Rewrapping means taking the encoded contents out of one container file-type and putting it in another, with no decode/re-encode happening. For example, given a [.mov] file, one might rewrap it to a [.avi] file. These file-types are each merely containers, designed to contain various encode formats (e.g. DV, Lagarith, Cineform, DivX) without having to “understand” them.
Rewrapping may for example be required for some Windows-based applications, that either don’t handle [.mov], either at all or (as I have encountered) not fully. Similarly, some applications (Windows or Mac based) will only work (or work properly) with [.mov] files. For instance I have found the Windows variant of Boris RED (versions 4 and 5) to work properly with HD 50 fps progressive only via [.mov] container, as reported at http://forums.creativecow.net/thread/15/859544 while someone else has found Avid Media Composer 5 to prefer [.mov], reported at http://community.avid.com/forums/p/84923/487414.aspx.
One tool for doing this: HDLink, a utility bundled with the Windows version of Go-Pro-Cineform “visually lossless” wavelet-based codec (that I have used for a number of years). HDLink can convert Cineform files from [.mov] to [.avi] and vice-versa. Incidentally, for the Mac version of Cineform, there is a broadly equivalent utility called ReMaster, but that can only convert in one direction, from [.avi] to [.mov].
To re-wrap:
- (Just now, I merely did [Convert] tab, select file and [Start], ans all worked fine, but maybe full work instruction should be as follows?)
- Use HDLink’s [Convert] tab.
- Select/Ensure the required destination file-type:
- Click [Prefs] button (at bottom of dialog)
- In [Prefs], ensure [Destination File Format for … Conversion] is set as you require.
- And (I guess?) enable [Force re-wrap CF MOV->AVI], to ensure it doesn’t sneakily do a transcode?
- Select the Input file and go.
- The rewrapped version will appear in the same folder.
The process is of course much faster than transcoding, involving simple computation, hence the overall speed will tend to be limited by the storage (e.g. hard disk and/or its transfer bus, especially if it’s a slow old thing like USB2) rather than the CPU (which may consequently show an extremely low % usage).
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