Data transform processing apparatus and method
AssigneeCanon Kabushiki Kaisha
InventorTadayoshi Nakayama
Life of this patent
Estimating the term…
Abstract
A data transform processing apparatus comprising a first lossless transform circuit to perform two step ladder operation processings of receiving unweighted normalized data then outputting weighted nonnormalized rotation-transformed data, and a second lossless transform circuit to perform two step ladder operation processings of receiving the weighted nonnormalized rotation-transformed data from the first lossless transform circuit then performing inverse weighting and outputting unweighted normalized rotation-transformed data, wherein the outputs from the first lossless transform circuit are interchanged and supplied to the second lossless transform circuit.
Claims4
A data transform apparatus for converting four items of input data X0, X1, X2 and X3 into four items of data in a frequency space, wherein the input data X0, X1, X2 and X3 are integers, the apparatus comprising:
- a first multiplier configured to multiply the input data X1 by a first coefficient;
- a second multiplier configured to multiply the input data X2 by a second coefficient;
- a first rounding processor configured to perform rounding processing on an output of said first multiplier;
- a second rounding processor configured to perform rounding processing on an output of said second multiplier;
- a first calculator configured to add an output of said first rounding processor to the input data X0;
- a second calculator configured to add an output of said second rounding processor to the input data X3;
- a third rounding processor configured to obtain difference data between an output of said first calculator and an output of said second calculator, to multiply the difference data by a third coefficient and to perform rounding processing on the result of multiplication of the difference data by the third coefficient;
- a third calculator configured to add an output of said third rounding processor to the input data X1;
- a fourth calculator configured to add an output of said third rounding processor to the input data X2;
- a fourth multiplier configured to multiply an output of said third calculator by the second coefficient;
- a fifth multiplier configured to multiply an output of said fourth calculator by the first coefficient;
- a fourth rounding processor configured to perform rounding processing on an output of said fourth multiplier;
- a fifth rounding processor configured to perform rounding processing on an output of said fifth multiplier;
- a fifth calculator configured to add an output of said fourth rounding processor to an output of said second calculator;
- and
- a sixth calculator configured to add an output of said fifth rounding processor to an output of said first calculator,
- wherein the outputs of said third, fourth, fifth and sixth calculators are output as the four items of data in the frequency space.
A data transform method of converting four items of input data X0, X1, X2 and X3 into four items of data in a frequency space, wherein the input data X0, X1, X2 and X3 are integers, the method comprising:
- a first multiplying step of multiplying the input data X1 by a first coefficient;
- a second multiplying step of multiplying the input data X2 by a second coefficient;
- a first rounding step of performing rounding processing on an output obtained in said first multiplying step;
- a second rounding step of performing rounding processing on an output obtained in said second multiplying step;
- a first calculating step of adding an output obtained in said first rounding step to the input data X0;
- a second calculating step of adding an output obtained in said second rounding step to the input data X3;
- a third rounding step of obtaining difference data between an output obtained in said first calculating step and an output obtained in said second calculating step, multiplying the difference data by a third coefficient and performing rounding processing on the result of multiplication of the difference data by the third coefficient;
- a third calculating step of adding an output obtained in said third rounding step to the input data X1;
- a fourth calculating step of adding an output obtained in said third rounding step to the input data X2;
- a fourth multiplying step of multiplying an output obtained in said third calculating step by the second coefficient;
- a fifth multiplying step of multiplying an output obtained in said fourth calculating step by the first coefficient;
- a fourth rounding step of performing rounding processing on an output obtained in said fourth multiplying step;
- a fifth rounding step of performing rounding processing on an output obtained in said fifth multiplying step;
- a fifth calculating step of adding an output obtained in said fourth rounding step to an output obtained in said second calculating step;
- and
- a sixth calculating step of adding an output obtained in said fifth rounding step to an output obtained in said first calculating step,
- wherein the outputs obtained in said third, fourth, fifth and sixth calculating steps are output as the four items of data in the frequency space.
A data transform apparatus for converting four items of input data X0, X1, X2 and X3 into four items of data in a frequency space, wherein the input data X0, X1, X2 and X3 are integers, the apparatus comprising:
- a first calculator configured to add the input data X3 to the input data X2;
- a second calculator configured to subtract the input data X1 from the input data X0;
- a rounding processor configured to obtain difference data between an output of said first calculator and an output of said second calculator, to multiply the difference data by a coefficient and to perform rounding processing on the result of multiplication of the difference data by the coefficient;
- a third calculator configured to add the input data X1 to an output of said rounding processor;
- a fourth calculator configured to add the input data X2 to the output of said rounding processor;
- a fifth calculator configured to subtract an output of said fourth calculator from an output of said second calculator;
- and
- a sixth calculator configured to add an output of said first calculator to an output of said third calculator,
- wherein the outputs of said third, fourth, fifth and sixth calculators are output as the four items of data in a frequency space.
Dependencies are inferred from the claim text.