Encoding/decoding method and apparatus for coding unit partitioning

An image encoding method performed by an image encoding apparatus (20) comprising a prediction unit (200), the image encoding method comprising:

• generating, by the prediction unit (200), a prediction pixel of a current block of a first color space, the prediction pixel of the current block being generated by using a plurality of reference pixels belonging to a corresponding block of a second color space;
• deriving, by the prediction unit (200), correlation information between the current block of the first color space and the corresponding block of the second color space, using a first neighboring region adjacent to the current block of the first color space and a second neighboring region adjacent to the corresponding block of the second color space;
• correcting, by the prediction unit (200), the prediction pixel of the current block based on the correlation information;
• generating, by the image encoding apparatus (20), a residual pixel for the current block based on the corrected prediction pixel;
• and
• encoding, by the image encoding apparatus (20), the current block of the first color space based on the residual pixel,
• wherein generating the prediction pixel of the current block of the first color space comprises performing a filtering on the reference pixels belonging to the corresponding block of the second color space,
• wherein the reference pixels include at least one of a filtering target pixel or a neighboring pixel of the filtering target pixel,
• wherein the neighboring pixel of the filtering target pixel includes at least one of a top pixel, a left pixel, a right pixel, a top-left pixel, a top-right pixel, a bottom pixel, a bottom-left pixel or a bottom-right pixel adjacent to the filtering target pixel, and
• wherein a flag for determining a number of the reference pixels to be used to generate the prediction pixel of the current block of the first color space is encoded.

A method of transmitting a bitstream performed by an image encoding apparatus (20) comprising a prediction unit (200), the method comprising:

• generating, by the prediction unit (200), a prediction pixel of a current block of a first color space, the prediction pixel of the current block being generated by using a plurality of reference pixels belonging to a corresponding block of a second color space;
• deriving, by the prediction unit (200), correlation information between the current block of the first color space and the corresponding block of the second color space, using a first neighboring region adjacent to the current block of the first color space and a second neighboring region adjacent to the corresponding block of the second color space;
• correcting, by the prediction unit (200), the prediction pixel of the current block based on the correlation information;
• generating, by the image encoding apparatus (20), a residual pixel for the current block based on the corrected prediction pixel;
• encoding, by the image encoding apparatus (20), the current block of the first color space based on the residual pixel to generate the bitstream;
• and
• transmitting, by the image encoding apparatus (20), the generated bitstream to an image decoding apparatus,
• wherein generating the prediction pixel of the current block of the first color space comprises performing a filtering on the reference pixels belonging to the corresponding block of the second color space,
• wherein the reference pixels include at least one of a filtering target pixel or a neighboring pixel of the filtering target pixel,
• wherein the neighboring pixel of the filtering target pixel includes at least one of a top pixel, a left pixel, a right pixel, a top-left pixel, a top-right pixel, a bottom pixel, a bottom-left pixel or a bottom-right pixel adjacent to the filtering target pixel, and
• wherein a flag for determining a number of the reference pixels to be used to generate the prediction pixel of the current block of the first color space is encoded.

A method of transmitting a bitstream generated by an image encoding method, wherein the image encoding method comprising:

• generating, by a prediction unit (200), a prediction pixel of a current block of a first color space, the prediction pixel of the current block being generated by using a plurality of reference pixels belonging to a corresponding block of a second color space;
• deriving, by the prediction unit (200), correlation information between the current block of the first color space and the corresponding block of the second color space, using a first neighboring region adjacent to the current block of the first color space and a second neighboring region adjacent to the corresponding block of the second color space;
• correcting, by the prediction unit (200), the prediction pixel of the current block based on the correlation information;
• generating, by an image encoding apparatus (20), a residual pixel for the current block based on the corrected prediction pixel;
• encoding, by the image encoding apparatus (20), the current block of the first color space based on the residual pixel to generate the bitstream;
• and
• transmitting, by the image encoding apparatus (20), the generated bitstream to an image decoding apparatus,
• wherein generating the prediction pixel of the current block of the first color space comprises performing a filtering on the reference pixels belonging to the corresponding block of the second color space,
• wherein the reference pixels include at least one of a filtering target pixel or a neighboring pixel of the filtering target pixel,
• wherein the neighboring pixel of the filtering target pixel includes at least one of a top pixel, a left pixel, a right pixel, a top-left pixel, a top-right pixel, a bottom pixel, a bottom-left pixel or a bottom-right pixel adjacent to the filtering target pixel, and
• wherein a flag for determining a number of the reference pixels to be used to generate the prediction pixel of the current block of the first color space is encoded.

A non-transitory computer-readable storage medium storing a bitstream that is generated by a method of encoding an image, the method of encoding the image comprising:

• generating, by a prediction unit (200), a prediction pixel of a current block of a first color space, the prediction pixel of the current block being generated by using a plurality of reference pixels belonging to a corresponding block of a second color space;
• deriving, by the prediction unit (200), correlation information between the current block of the first color space and the corresponding block of the second color space, using a first neighboring region adjacent to the current block of the first color space and a second neighboring region adjacent to the corresponding block of the second color space;
• correcting, by the prediction unit (200), the prediction pixel of the current block based on the correlation information;
• generating, by an image encoding apparatus (20), a residual pixel for the current block based on the corrected prediction pixel;
• and
• encoding, by the image encoding apparatus (20), the current block of the first color space based on the residual pixel,
• wherein generating the prediction pixel of the current block of the first color space comprises performing a filtering on the reference pixels belonging to the corresponding block of the second color space,
• wherein the reference pixels include at least one of a filtering target pixel or a neighboring pixel of the filtering target pixel,
• wherein the neighboring pixel of the filtering target pixel includes at least one of a top pixel, a left pixel, a right pixel, a top-left pixel, a top-right pixel, a bottom pixel, a bottom-left pixel or a bottom-right pixel adjacent to the filtering target pixel, and
• wherein a flag for determining a number of the reference pixels to be used to generate the prediction pixel of the current block of the first color space is encoded.