Method and apparatus for encoding and decoding image using image separation based on bit location

A method of decoding an image, the method comprising:

• decoding a bitstream of n-m bit planes based on n-m most significant bits of n-bit pixel values, by using bit plane-based image decoding, to generate the n-m bit planes;
• decoding, by using an apparatus, a bitstream of an image based on m least significant bits of the n-bit pixel values, by using block-based image decoding to generate the image based on m least significant bits;
• and
• generating an output image comprising the n-bit pixel values, from the n-m bit planes and the image based on the m least significant bits,
• wherein n and m are positive integers satisfying 0<m<n.

An apparatus for encoding an image, the apparatus comprising:

• an image divider which generates from an input image comprising n-bit pixel values, n-m bit planes based on n-m most significant bits of the n-bit pixel values and an image based on m least significant bits of the n-bit pixel values;
• a first encoder which encodes each of the n-m bit planes by using bit plane-based image encoding;
• a second encoder which encodes the image based on the m least significant bits of the n-bit pixel values by using block-based image encoding;
• and
• a multiplexer which multiplexes the encoded n-m bit planes and the encoded image based on the m least significant bits generated by the first and second encoders,
• wherein n and m are positive integers satisfying 0<m<n.

An apparatus for decoding an image, the apparatus comprising:

• an demultiplexer which demultiplexes data of an output image comprising n-bit pixel values into data of n-m bit planes based on n-m most significant bits of the n-bit pixel values and data of an image based on m least significant bits of the n-bit pixel values;
• a first decoder which decodes the data of the n-m bit planes based on the n-m most significant bits of the n-bit pixel values, by using bit plane-based image decoding;
• a second decoder which decodes the image based on the m least significant bits of the n-bit pixel values, by using block-based image decoding;
• and
• an image restorer which generates the output image comprising the n-bit pixel values, from the n-m bit planes and the image based on the m least significant bits,
• wherein n and m are positive integers satisfying 0<m<n.

A non-transitory computer readable recording medium having recorded thereon a program for executing a method for encoding an image, the method comprising:

• generating, from an input image comprising n-bit pixel values, n-m bit planes based on n-m most significant bits of the n-bit pixel values and an image based on m least significant bits of the n-bit pixel values;
• encoding each of the n-m bit planes by using bit plane-based image encoding;
• and
• encoding the image based on the m least significant bits of the n-bit pixel values by using block-based image encoding,
• wherein n and m are positive integers satisfying 0<m<n.

A non-transitory computer readable recording medium having recorded thereon a program for executing a method of decoding an image, the method comprising:

• decoding a bitstream of n-m bit planes based on n-m most significant bits of n-bit pixel values, by using bit plane-based image decoding, to generate the n-m bit planes;
• decoding a bitstream of an image based on m least significant bits of the n-bit pixel values, by using block-based image decoding to generate the image based on m least significant bits;
• and
• generating an output image comprising the n-bit pixel values, from the n-m bit planes and the image based on the m least significant bits,
• wherein n and m are positive integers satisfying 0<m<n.