Image decoding device, image decoding method, and storage medium and integrated circuit thereof

An integrated circuit device comprising an image decoding circuit which decodes encoded animation data and outputs pictures in the order of displaying each picture according to the encoded animation data, comprising:

• a frame rate information extracting means which extracts frame rate information corresponding to each picture contained in a stream from an input stream;
• a storing means which temporarily stores the frame rate information extracted by the frame rate information extracting means;
• a dot clock output means which outputs a dot clock in order to display images;
• and
• a control means which switches the frequency of the dot clock output by the dot clock output means when the output frame rate information stored in the storing means is read in the order of displaying each picture and when the dot clock of the arrayed frame rate information changes.

An image decoding method comprising an image decoding system which decodes encoded animation data and outputs pictures in the order of displaying each picture according to the encoded animation data, comprising the steps of:

• a frame rate information extracting step which extracts frame rate information corresponding to each picture contained in a stream from an input stream;
• a storing step which temporarily stores the frame rate information extracted by the frame rate information extracting step;
• a dot clock output step which outputs a dot clock in order to display images;
• and
• a control step which switches the frequency of the dot clock output by the dot clock output step when the output frame rate information stored in the storing step is read in the order of displaying each picture and when the dot clock of the arrayed frame rate information changes.

A storage medium which is readable by a computer, storing an image decoding program for making a computer execute a decoding operation on encoded animation data and an outputting operation on pictures in the order of displaying each picture according to the encoded animation data, the image decoding program comprising the steps of:

• a frame rate information extracting step which extracts frame rate information corresponding to each picture contained in a stream from an input stream;
• a storing step which temporarily stores the frame rate information extracted by the frame rate information extracting step;
• a dot clock output step which outputs a dot clock in order to display images;
• and
• a control step which switches the frequency of the dot clock output by the dot clock output step when the output frame rate information stored in the storing step is read in the order of displaying each picture and when the dot clock of the arrayed frame rate information changes.