What is AVIF
A new technology that is exciting to us is the AV1 image file format (.avif). It is a super-compressed image format. Netflix has considered the .avif format superior to JPEG, PNG, and even the newer WebP image formats in image quality to compressed file size ratio. It was developed by the Alliance for Open Media in collaboration with Google, Cisco, and Xiph.org (which worked with Mozilla, the company that created the Firefox browser). The format was designed to be an open-source, royalty-free image format. The format has several advantages, including supporting any image codec, being lossless or lossy, having an alpha channel (transparency for UI and design elements), and even storing a series of animated frames (think lightweight, high-quality animated GIFs). Also, it is one of the first formats to support HDR color, allowing for increased brightness, color bit depth, and wide color gamuts.
What is Skype
Skype is a proprietary telecommunications application designed to provide VoIP-based video telephony, videoconferencing, and voice calls. Among other features, it offers instant messaging, file transfer, debit-based calls to landline and mobile telephones (over traditional telephone networks), and others. The Skype client is available on a wide variety of platforms, including desktop, mobile, and video game consoles, and is operated by Skype Technologies, a Microsoft division. It is estimated that 100 million people use Skype each month and 40 million people use it daily as of March 2020.
To this date, a forum post exists that suggests adding support for AVIF. The post did not get much traction. Skype downloads but does not display AVIF files. It is uncertain whether Skype will add support in the future.