Step 1: Free download and Install the AVI to Apple TV for Mac.
Step 2: Run the Mac AVI to Apple TV for Mac.
And then you will see the following friendly interface.

Step 3: load AVI files by clicking "Add Files" button.
Step 4: Click the down arrow to select Apple TV format as the output format.
Step 5: Click "Browse" button near the Output Folder to select the destination folder to save.

Step 6: Click "Convert" button to start converting automatically.

If the conversion is over, the above dialog will appear. Click "ok" to finish the whole conversion and then you can directly open the converted files from the folder that you have previously setted.
With the AVI to Apple TV for Mac, enjoying the favorite AVI files with Apple TV is not a difficult thing. Free download and have a try.