A variable-length encoder that feeds a Coded Block Pattern (CBP) as an input symbol to variable-length code output part. Coded symbol memory supplies CBPs in neighboring blocks as coding map table reference information to coding map table provider. Coding map table provider determines a coding map table used in coding of the CBP, based on these CBPs in the neighboring blocks, and provides a coding map table H4 to variable-length code output part. Variable-length coding table provider feeds a variable-length coding table to variable-length code output part. Then the coding target CBP is subjected to variable-length coding, and the resultant is outputted as coded data. This allows information source coding of coding symbols to be performed efficiently according to the coding condition and the property of image.