There seems to exist a Japanese software called ClippingSticker that can export Picture Clipping files (.pictclipping) from MacOS (Mac OS X) to many different bitmap formats, including the JPEG format (.jpg, .jpeg). Often used to get the pictures to a common format that can be opened with every graphics editor.
Convert Picture Clipping data to JPEG bitmap image format.
We found one software available in the database for this conversion.
Apple macOS / Mac OS X software - convert pictclipping to jpg on OS X
A program for exporting clipping images
Convert from pictclipping file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.