The operation of decoding an image file in a supported format into a PixelMap for image display or processing. Currently, the following image formats are supported: JPEG, PNG, GIF, RAW, WebP, BMP, and HEIC (since API version 12).
The operation of encoding a PixelMap into an image in different formats for subsequent processing, such as storage and transmission. Currently, images in the following formats can be encoded: JPEG, WebP, PNG, HEIC (available since API version 12), and GIF (available since API version 18, which requires PackToDataFromPixelmapSequence or PackToFileFromPixelmapSequence for encoding).
Reference
Using ImageSource to Decode Images