Artist/performer
Cover (back)
Band/artist logotype
Band/orchestra
Composer
Conductor
During performance
During recording
A fish as funny as the ID3v2 spec
Cover (front)
Illustration
Lead artist/lead performer/soloist
Leaflet page
Lyricist/text writer
Medium (e.g. label side of CD)
No image type. Can be used to tell functions such as gst_tag_image_data_to_image_sample() that no image type should be set.
Publisher/studio logotype
Recording location
Undefined/other image type
Movie/video screen capture
Type of image contained in an image tag (specified as "image-type" field in the info structure in the image's #GstSample)