An Alpha channel defines the transparency in a video clip or picture. Transparency is assigned to the pixel. In After Results, in case you create a composition that you just intend for one thing to be seen beneath, or seen by the “empty” space if you find yourself utilizing it in postproduction, that you must export your clip with alpha.
While you add your composition to the render queue, click on on the output module settings. Within the video output part, you’ll see a drop-down by the phrase Channels. That is the place you choose RGB, Alpha, or RGB+Alpha. RGB+Alpha ought to be chosen, and it will export your video with the alpha channel.
Nonetheless, not all video codecs/codecs assist alpha. In After Results, the Animation codec does, in addition to Apple ProRes 4444, Apple ProRes 4444 XQ, and some others. It’s essential to choose considered one of these codecs to have the RGB+Alpha choice develop into out there.
If you happen to export your composition utilizing Adobe Media Encoder, as soon as you choose a correct format that helps alpha (akin to QuickTime), you will note an inventory beneath the presets drop-down. Media Encoder lets you realize which choices embrace alpha.
Watch this quick video for a visible demonstration of exporting with alpha channel:
