The present disclosure relates to imaging for determination of crustacean physical attributes. An infrared spectrum image of a shell of a live crustacean is captured and processed to determine a physical attribute of the shell of the live crustacean. A characteristic of a pattern on the shell that is indicative of moult stage of the live crustacean is detected, from the captured image. Multiple images may be used in some embodiments, including not only infrared spectrum images, but also images of different types such as visible spectrum images and/or ultraviolet spectrum images.
