Image change detecting apparatus and image change detecting method, image encoding apparatus and information recording medium having image change detecting program recorded in computer readable manner

An image encoding apparatus including an image change detecting apparatus for detecting generation of a fade change in image information containing a plurality of field images,

• the image change detecting apparatus comprising:
• a dispersion value detecting device for detecting each of intra-field dispersion value in each field image;
• an average direct current level detecting device for detecting each of intra-field average direct current levels in each field image;
• and
• a detecting device for detecting whether or not the fade change occurs based on a change of the detected intra-field dispersion value and a change of the detected intra-field average direct current level,
• the image encoding apparatus further comprising:
• an encoding device for changing an encoding parameter in encoding of the detected subsequent image information, thereby encoding the image, when it is detected that the fade change occurs.

An image change detecting method for detecting an occurrence of a fade change in image information containing a plurality of field images, the image change detecting method comprising the processes of:

• detecting each of the intra-field dispersion values in the each field image;
• detecting each of the intra-field average direct current level in each field image;
• and
• detecting an occurrence of the fade change based on a change of the detected intra-field dispersion value and a change of the detected intra-field average direct current level.

An information recording medium in which an image change detecting program is readably recorded by a computer included in a image change detecting apparatus for detecting generation of a fade change in image information containing a plurality of field images, the image change detecting program causing the computer to function as:

• a dispersion value detecting device for detecting each of the intra-field dispersion values in each field image;
• an average direct current level detecting device for detecting each of the infra-field average direct current levels in each field image;
• and
• a detecting device for detecting an occurrence of the fade change based on a change of the detected intra-field dispersion value and a change of the detected intra-field average direct current level.