Patent ID: 6873736

Claim:
An encoder for encoding an arbitrarily shaped object image on a block base, wherein the arbitrarily shaped object image comprising a shape signal indicating whether a pixel is outside an arbitrarily shaped object (insignificant) or inside the arbitrarily shaped object (significant) and a texture signal indicating a pixel texture value of a pixel inside the arbitrarily shaped object, the encoder comprising: resolving means for resolving the arbitrarily shaped object image into a plurality of blocks, encoding means for encoding the block to produce a compressed data, decoding means for decoding the compressed data into a reproduced block, padding means for padding a pixel texture value of an insignificant pixel within the reproduced block, wherein the reproduced block padded at the padding means is stored in a frame memory, wherein the padding means comprises a boundary block padding means and a first exterior block padding means, the boundary block padding means pads a pixel texture value of an insignificant pixel within the reproduced block, when the reproduced block is a boundary block lying on an arbitrarily shaped object boundary, using a pixel texture value generated from a pixel texture value of a significant pixel on the arbitrarily shaped object boundary; and the first exterior block padding means pads a pixel texture value of an insignificant pixel within the reproduced block, when the reproduced block is a first exterior block including no significant pixel, using a pixel texture value at a block boundary of the boundary block, the first exterior block being immediately adjacent to the boundary block, and the pixel texture values of all insignificant pixels within the boundary block having been padded by the boundary block padding means for padding the pixel texture value of the insignificant pixel within the boundary block.