I know I replied to your post in the other thread, but just to be complete... The ".cpi" file does not contain any actual video or audio data, but it does have information *about* the video and audio contained in the MTS files
http://www.fileinfo.com/extension/cpi
The .cpi file contains only indexed text information that the camcorder uses for playback or if the camcorder's built-in effects are used for playback from the camcorder.
If the video (and .cpi) files are still in the camcorder, then connect the camcorder and Mac, and do the import/capture as you previously (successfully) had done. If the MTS files have been copied from the camcorder to the Mac (along with the .cpi file), then the MTS files will need to be converted to a file format iMovie can deal with (MOV or MP4 are most common). To do this conversion - transcoding - a utility applications is required.
Download and install MPEG StreamClip
http://www.apple.com/downloads/macosx/video/mpegstreamclip.html
Transcode the MTS files. Launch iMovie, drag the converted files to iMovie's sequence area... In this transcoding case, the .cpi files are useless.
There are other transcoders - I happen to like MPEG StreamClip. HandBrake http://handbrake.fr/ is another very useful video editing tool... Audacity http://audacity.sourceforge.net/ is a very useful and powerful audio editor.
I'm thinking it might be a Sony vs Mac thing to be honest. We've just got the Sony HXR-MC50 HD camera which is a real beauty, but I just can't seem to get the files onto my macbook for editing. I got it right the first time, just opened iMovie and imported from camera archive and all was well in the land. Until I tried to offline the next lot but the file type (CPI) is not supported nor recognised and everything is greyed out. I've tried a few file converter downloads, but nothing seems to be working at all. Really frustrating considering the Sony chap said it wouldn't be a problem with mac...
If you've found a solution, I'd really appreciate your advice and direction. I've just learnt to spell mac so I'm a real baby when it comes to all the jargon. I might ask you to draw me a picture... (", I don't know what to tell you as far as my system info goes, other than I have a macbook and something about Mac OS Extended and Macintosh HD...

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