An image compression apparatus and method capable of performing compression with different image qualities within an image. In a mosaic processing unit (16) of the image compression apparatus, a filtering region divider (130) divides input image data into a plurality of filtering areas and at least some of the filtering areas are subjected to unification processing for each of the filtering areas by a filtering unit (131). On the other hand, a JPEG encoder (17) divides the image data after the mosaic processing into a plurality of rectangular block areas and each of the block areas is subjected to DCT processing and quantization processing. Here, the filtering area consists of adjacent one or more sets of rectangular areas each consisting of two or more pixels obtained by equally dividing the aforementioned block area by 2n (n is a natural number).