ENCODING METHOD, DECODING METHOD FOR IMAGE, ENCODER, DECODER FOR IMAGE AND STORAGE MEDIUM IN WHICH IMAGE ENCODING PROGRAM, IMAGE DECODING PROGRAM ARE RECORDED

摘要

PROBLEM TO BE SOLVED: To enhance encoding efficiency of an image with clear line arts like animation video, etc. SOLUTION: The line arts are detected from an original image 1 and an line art image 3 is generated by line art image generating part 2. The line art image 3 is encoded and outputted to a multiplexing part 8 as an encoded line art image 6 at line art image encoding part 4. The original image 1 is encoded and outputted to the multiplexing part 8 as an encoded original image 7 at an original image encoding part 5. The encoded line art image 6 and the encoded original image 7 are multiplexed and outputted as a multiplexed and encoded image 9 at the multiplexing part 8. The multiplexed and encoded image 9 is inputted in a separating part 21 and is separated into an encoded line art image 22 and an encoded original image 23 at the decoder side. The encoded line art image 22 and the encoded original image 13 are decoded and outputted to a synthesizing part 28 as a decoded line art image 16 and a decoded original image 17 respectively by line art image decoding part 24 and an original image decoding part 25. A decoded line art image 26 and a decoded original image 27 are synthesized and outputted as an outputted image 29 by the synthesizing part 28.