Residual up-sampling apparatus for performing transform block up-sampling and residual down-sampling apparatus for performing transform block down-sampling

A residual up-sampling circuit comprising:

• a residual up-sampling transpose buffer, arranged to store an intermediate residual up-sampling result;
• a first-direction residual up-sampling circuit, arranged to preform one of vertical up-sampling and horizontal up-sampling, wherein said one of the vertical up-sampling and the horizontal up-sampling comprises processing an inverse transform output of an inverse transform circuit to generate the intermediate residual up-sampling result to the residual up-sampling transpose buffer;
• and
• a second-direction residual up-sampling circuit, arranged to perform another of the vertical up-sampling and the horizontal up-sampling, wherein said another of the vertical up-sampling and the horizontal up-sampling comprises performing transpose access upon the residual up-sampling transpose buffer to retrieve the intermediate residual up-sampling result, and processing the intermediate residual up-sampling result to generate a final residual up-sampling result, wherein the first-direction residual up-sampling circuit and the second-direction residual up-sampling circuit are two separate circuits;
• wherein one of the first-direction residual up-sampling circuit and the second-direction residual up-sampling circuit starts processing residuals of a transform block before another of the first-direction residual up-sampling circuit and the second-direction residual up-sampling circuit finishes processing residuals of the transform block;
• or
• wherein one of the first-direction residual up-sampling circuit and the second-direction residual up-sampling circuit starts processing residuals of one transform block before another of the first-direction residual up-sampling circuit and the second-direction residual up-sampling circuit finishes processing residuals of another transform block.

A residual down-sampling circuit comprising:

• a residual down-sampling transpose buffer, arranged to store an intermediate residual down-sampling result;
• a first-direction residual down-sampling circuit, arranged to preform one of vertical down-sampling and horizontal down-sampling, wherein said one of the vertical down-sampling and the horizontal down-sampling comprises processing a residual generation output of a residual generation circuit to generate the intermediate residual down-sampling result to the residual down-sampling transpose buffer;
• and
• a second-direction residual down-sampling circuit, arranged to perform another of the vertical down-sampling and the horizontal down-sampling, wherein said another of the vertical down-sampling and the horizontal down-sampling comprises performing transpose access upon the residual down-sampling transpose buffer to retrieve the intermediate residual down-sampling result, and process the intermediate residual down-sampling result to generate a final residual down-sampling result, wherein the first-direction residual down-sampling circuit and the second-direction residual down-sampling circuit are two separate circuits;
• wherein one of the first-direction residual down-sampling circuit and the second-direction residual down-sampling circuit starts processing residuals of a transform block before another of the first-direction residual down-sampling circuit and the second-direction residual down-sampling circuit finishes processing residuals of the transform block;
• or
• wherein one of the first-direction residual down-sampling circuit and the second-direction residual down-sampling circuit starts processing residuals of one transform block before another of the first-direction residual down-sampling circuit and the second-direction residual down-sampling circuit finishes processing residuals of another transform block.