Shotwell supports JPEG, PNG, TIFF, BMP, GIF, WebP and RAW photo files.
Shotwell's RAW format support is currently limited. When you view a RAW photo, you are actually viewing a JPEG derived from the RAW photo, not the RAW image itself. Additionally, the RAW editing pipeline is not fully 16-bit - you can only export edited photos as 8-bit files. Most supported formats can be used for export (JPEG, PNG, TIFF, BMP).
For more information about RAW-format photos in Shotwell, please see the RAW section.
Shotwell also supports video files in any format supported by the GStreamer media library on the system where Shotwell is running. This typically includes the following formats among others:
Container formats: Ogg, QuickTime, MP4, AVI.
Codecs: Theora, Quicktime, MPEG-4, Motion JPEG. Note that some operating systems may not include all codecs listed here due to legal or licensing restrictions.
Shotwell supports both photos and videos, but for simplicity, this documentation uses just the term "photos" in most places. Many operations in Shotwell apply to both photos and videos, however. In particular, events, flagging, rating, tagging, and publishing work both for photos and for videos.