To provide a slow motion image detection device that has simple arithmetic processings and configuration required for detecting a slow motion image from a moving image coded by a coding algorithm, including an inter- frame predictive coding algorithm.

A variable length decoder 110 of the slow motion image detecting device 100 receives data coded by a coding algorithm, in compliance with the MPEG standards. A variable length decoder 110 applies variable length decoding to the received coded data and provides an output of a picture coding type(PCT), a macroblock address increment(MBAI) and a motion vector(MVC) to a discrimination processing section 111. The discrimination processing section 111 estimates the motion of a series of images configuring a moving image based on the information items above and detects it to be a slow motion image, when static images are periodically consecutive.