1. Launch Adobe Premiere on your computer. To launch the program from the "Start" menu, go to "All Programs," click the "Adobe" folder and then click "Adobe Premiere."

2. Add the AVI file that you want to crop to Adobe Premiere. Go to "File>Import>File" and find the file in the window that comes up.

3. Drag the AVI file to the video track of the Adobe Premiere timeline.

4. Go to the "Effects" tab to open the "Effects" pane. If "Effects" is not showing in Premiere, go to the "Windows" menu and click "Effects" to open the window.

5. Click the "Transform" folder in the "Effects" menu to show the transformation tools. Click on "Crop" and drag it onto the AVI clip in the timeline.

6. Crop the video by entering numbers into the "Left," "Right," "Top" and "Bottom" boxes. This is the percentage of each part of the video that is cut away. Try different numbers until only the part of the image that you want to keep shows.

7. Check the "Zoom" or "Resize" box to zoom in so that the cropped part of the video expands to fill the entire screen.

8. Export the cropped video by going to "File>Export>Movie." Enter a name for the cropped video and choose the location on your computer where you want the video to save. Click "Export," and the video exports to the selected folder as AVI.

1. Open iMovie by clicking the icon on the floating icon bar or by going to the Finder and "Applications."

2. Click "File" and "Import" to pull in the AVI file. Find the file in the window that comes up, and double-click the file.

3. Drag the clips of the AVI file into the timeline. The file automatically splits into clips when imported, but you can select all of the clips at one time by right-clicking on any clip from the file and choosing "Select Entire Clip." Then, the clip can be moved to the timeline at once.

4. Click on one clip at a time in the timeline to select it. When the clip appears in the preview window, click on one of the triangles at the bottom of the clip and move it upward and inward to make a box around the portion of the clip you want to crop. Click the "Edit" menu, and choose "Crop" to crop the clip to size.

5. Export the movie by going to "Share" and "Export as QuickTime." The movie saves to your computer in QuickTime movie, or MOV, format.

I know a step by step guide on how to crop avi files at http://www.bigasoft.com/articles/how-to-crop-video-files.html

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