Remove alpha channel in an image

Question

I have an app icon for iOS but Apple doesn\'t allow alpha to be in the image. How to remove this alpha channel? I only have the png image with me I don\'t have the source fi

Answer 1

Just got the the following error when trying to upload my app to the iTunes app store:

iTunes Store Operations Failed

ERROR ITMS-90717: "Invalid App Store Icon. The App Store icon in the asset catalog in 'MyApp.app' can't be transparent nor contain an alpha channel."

I confirmed that my app store icons did include the alpha channel by locating the asset in Finder and looking up its info (⌘+i). Underneath More info, it showed:

Alpha channel: Yes

Found the solution above to use Preview to remove the alpha channel by exporting it with the Alpha checkbox unchecked, but figured a way to batch export them since I had 18 assets I needed to strip the alpha channel from.

The way I got batch exporting to work was to select all my app icon assets in finder > right click > open (or open with preview)

All of the assets will now appear in the same window. Select all (⌘+a), and then select File > Export Selected Images… > Expand Options > uncheck the Alpha checkbox > Choose (your destination folder)

Done! All your images are now exported with the alpha channel stripped off.