ACDSee Image

ACDSee is photo viewing, editing, and management software developed by ACD Systems^[1]. Early versions of the Photo Editor software could save a image with all editing intact using the APD extension^[2]. Later versions of Photo Editor and Ultimate software would save images and layers^[3] with the ACDC extension^[4].

Format Identification

APD & ACDC image formats are in fact TIFF images extended with additional features.

References

1. ↑ https://en.wikipedia.org/wiki/ACDSee
2. ↑ https://support.acdsee.com/en/support/solutions/articles/60000474856-why-does-acdsee-launch-when-i-double-click-on-my-photo-editor-file-
3. ↑ https://help.acdsystems.com/en/acdsee-ultimate-8/Content/1Topics/5_Process_mode/Editing/Layered%20Editor/IDDH_LAYERED_EDITOR.htm
4. ↑ https://www.acdsee.com/en/support/file-formats