Patent attributes
Even in the case of coding the input image by dividing into tiles, a fine image quality adjustment is possible based on the characteristic of each tile. The input image signal is transformed to the coded data through the tile dividing unit 102, the wavelet transforming unit 103, and the entropy coding unit 106, and is stored in the code memory 107. In parallel to this processing, the distortion calculating unit 108 calculates the distortion in each coding pass of each code block, and stores it in the distortion memory 109. On the other hand, the complex tile deciding unit 111 decides whether a particular tile is the complex tile or not. The tile classifying memory 112 stores the decision output. A distortion data outputted from the distortion memory 109 is outputted to the multiplier 110, the multiplier 110 multiplies the distortion data by the weight coefficient selected by the weight coefficient selecting unit 113. The weighted distortion of each coding pass is output to the rate controlling unit 114, the rate controlling unit 114 executes code amount control of coded data.