When you import AVI to iMovie, you may come across lots of problems, such as nothing shows up on the screen, or there is only image or you only get sound in iMovie. Well, according to Apple, iMovie (iMovie 11) only accepts MP4, M4V, MOV files. Since AVI is not supported by iMovie, in order to edit AVI videos in iMovie, you need to convert AVI videos to iMovie compatible format on Mac first before transferring the files to iMovie.
To fulfill your task, you can just get Video Converter for Mac, which can help you convert AVI video to iMovie supported videos with optimized settings while keeping the video quality. In addition, it can convert all other popular video formats like MP4, MOV, WMV, MKV, FLV, ASF, M2TS, VOB, etc. to iMovie compatible video formats and extract audio from videos to any popular audio formats like MP3, M4V, AAC, etc. Now get the tool and add AVI video files to iMovie effortlessly. If you want to convert AVI on iMovie on Windows, please turn to Video Converter Ultimate.
Free Download AVI to iMovie Converter
Click "Add Files" to load AVI files or directly drag them from your Mac into the Mac Video Converter. You can preview the videos in the right pane and take snapshots of the movies scenes you like.

You can select "iMovie" from the drop-down list of "Apple Software" and choose a destination folder for saving output files.

Finally, click Convert button to start converting your AVI files to iMovie on Mac. After the conversion, you can import the converted video files to iMovie for editing with ease.
Tips: iMovie is works with the following video formats: DV, DV Widescreen, HDV 1080i (25 and 30 fps), HDV 720p (25 and 30 fps), MPEG 4 Simple Profile, iSight. If you want to convert DVD and video to iMovie, all-in-one Mac DVD Video Converter is definitely specially designed for you.