Image encoder and decoder with area selection

摘要

An image encoder for encoding the image data so as to make the image quality of a selected area better than that of the other areas without increasing the amount of data is disclosed. The encoder comprises an area selecting section (101) for selecting a specific area in an image, an area position and shape encoding section (102) for encoding the position and shape of the selected area, a coding parameter adjusting section (104) for adjusting various parameters used to control the image quality and the amount of data in encoding a dynamic image and performing control so that the image quality of the area is encoded more preferably than the image quality of the other areas, a parameter encoding section (105) for encoding the above parameters, a dynamic image encoding section (106) for encoding input dynamic-image data by using the above various parameters, and an encoded data integrating section (103) for combining encoded data by the area position and shape encoding section (102), the parameter encoding section (105) and the dynamic image encoding section (106) and transmit or store the data. An image decoder applied to the image encoder is also disclosed.