| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image coding device with reduced power consumption, capable of effectively narrowing down the number of prediction modes and reducing the operation amount at coding and realizes coding of high coding efficiency. <P>SOLUTION: The device comprises a coding means 112 for selecting one prediction mode from a plurality of prediction modes and performing intra prediction coding; a prediction error detecting means 113 for detecting a prediction error; an operation setting means 132 for setting up a standard operation method and a high-definition operation method; and a mode setting means 111 for setting up first candidate modes and second candidate modes. In the standard operation, an intra-control portion 13a controls the coding means 112 so as to select a first candidate mode among the first candidate modes as the prediction mode, when a prediction error in the selected first candidate mode is lower than the threshold, and select the prediction mode from all prediction modes, when there is no prediction mode below the threshold. In the high-definition operation, upon detection of a prediction error for the first candidate modes, the intra control portion 13a controls the coding means 112 so as to select the prediction mode of a prediction error lower than a big expanded threshold or select the prediction mode with a minimum prediction error among the second candidate modes. <P>COPYRIGHT: (C)2008,JPO&INPIT |
