Information processing apparatus and information processing method for coding
An information processing apparatus includes a processor. the processor determines a sign of a first value on a basis of a result of an operation of a sum of products of a plurality of color-difference residuals and a plurality of luminance residuals, and calculates the first value on a basis of a first product of a sum of luminance residuals that are negative values among the plurality of luminance residuals and a constant when the sign of the first value is determined to be positive, and calculates the first value on a basis of a second product of a sum of luminance residuals that are positive values among the plurality of luminance residuals and the constant when the sign of the first value is determined to be negative.
1. An information processing apparatus comprising:
a processor configured to
determine a sign of a product sum obtained from a result of an operation of a sum of products of a plurality of color-difference residuals, which are differences between a color difference of each pixel of an image and a color difference of a corresponding pixel of a predicted image, and a plurality of luminance residuals, which are differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image, each pixel of the image corresponding to the corresponding pixel of the predicted image,
divide a first addition value by a sum of squares of each of the plurality of luminance residuals so as to calculate a first value when the sign of the product sum is determined to be positive, the first addition value being obtained by adding to the product sum a first product of a sum of first luminance residuals and a first coefficient value, the first luminance residuals being negative values among differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image,
divide a second addition value by a sum of squares of each of the plurality of luminance residuals so as to calculate the first value when the sign of the product sum is determined to be negative, the second addition value being obtained by adding to the product sum a second product of a sum of second luminance residuals and the first coefficient value, the second luminance residuals being positive values among differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image,
quantize the first value so as to calculate a second value, and
subtract a value from the plurality of color-difference residuals so as to calculate a cross component residual, the value being obtained by multiplying the second value and a second coefficient value by the plurality of luminance residuals and performing arithmetic right shift on the result thereof.
2. The information processing apparatus according to claim 1 , wherein
the processor
calculates the first value as zero when the product sum is zero.
3. The information processing apparatus according to claim 1 , wherein
the first value is a value that results in a minimum sum of squares of the cross component residual.
4. An information processing method executed by an information processing apparatus, the information processing method comprising:
determining, by a processor, a sign of a product sum obtained from a basis of a result of an operation of a sum of products of a plurality of color-difference residuals, which are differences between a color difference of each pixel of an image and a color difference of a corresponding pixel of a predicted image, and a plurality of luminance residuals, which are differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image, each pixel of the image corresponding to the corresponding pixel of the predicted image;
dividing, by the processor, a first addition value by a sum of squares of each of the plurality of luminance residuals so as to calculate a first value when the sign of the product sum is determined to be positive, the first addition value being obtained by adding to the product sum a first product of a sum of first luminance residuals and a first coefficient value, the first luminance residuals being negative values among differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image;
dividing, by the processor, a second addition value by a sum of squares of each of the plurality of luminance residuals so as to calculate the first value when the sign of the product sum is determined to be negative, the second addition value being obtained by adding to the product sum a second product of a sum of second luminance residuals and the first coefficient value, the second luminance residuals being positive values among differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image;
quantizing, by the processor, the first value so as to calculate a second value; and
subtracting, by the processor, a value from the plurality of color-difference residuals so as to calculate a cross component residual, the value being obtained by multiplying the second value and a second coefficient value by the plurality of luminance residuals and performing arithmetic right shift on the result thereof.
5. The information processing method according to claim 4 , further comprising:
calculating, by the processor, the first value as zero when the product sum is zero.
6. The information processing method according to claim 4 , wherein
the first value is a value that results in a minimum sum of squares of the cross component residual.
7. A non-transitory storage medium having stored therein a program that cases a computer to execute a process, the process comprising:
determining a sign of a product sum obtained from a result of an operation of a sum of products of a plurality of color-difference residuals, which are differences between a color difference of each pixel of an image and a color difference of a corresponding pixel of a predicted image, and a plurality of luminance residuals, which are differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image, each pixel of the image corresponding to the corresponding pixel of the predicted image;
dividing a first addition value by a sum of squares of each of the plurality of luminance residuals so as to calculate a first value when the sign of the product sum is determined to be positive, the first addition value being obtained by adding to the product sum a first product of a sum of first luminance residuals and a first coefficient value, the first luminance residuals being negative values among differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image;
dividing a second addition value by a sum of squares of each of the plurality of luminance residuals so as to calculate the first value when the sign of the product sum is determined to be negative, the second addition value being obtained by adding to the product sum a second product of a sum of second luminance residuals and the first coefficient value, the second luminance residuals being positive values among differences between luminance of each pixel of the image and luminance of the corresponding pixel of the predicted image;
quantizing the first value so as to calculate a second value; and
subtracting a value from the plurality of color-difference residuals so as to calculate a cross component residual, the value being obtained by multiplying the second value and a second coefficient value by the plurality of luminance residuals and performing arithmetic right shift on the result thereof.
8. The non-transitory storage medium according to claim 7 , wherein
the process further comprises:
calculating the first value as zero when the product sum is zero.
9. The non-transitory storage medium according to claim 7 , wherein
the first value is a value that results in a minimum sum of squares of the cross component residual.