Cross-component adaptive loop filter for chroma
AssigneeCanon Kabushiki Kaisha
InventorsJonathan TAQUET, Christophe GISQUET, Guillaume LAROCHE, Patrice ONNO
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Abstract
A method of filtering an image is disclosed, the method comprising: receiving filter coefficients and first component sample values corresponding to samples surrounding a reference sample, and inputting said filter coefficients and first component sample values into a cross component filter to produce a cross component filter output; wherein said cross-component filter uses a restricted number of bits to represent said filter coefficients and/or first component sample values to produce said filter output.
Claims15
A method of filtering an image portion using Cross-Component Adaptive Loop Filter, the method comprising:
- acquiring filter coefficients and first component sample values corresponding to samples surrounding a reference sample;
- and
- using said filter coefficients and first component sample values for the Cross-Component Adaptive Loop Filter to produce an output of the Cross-Component Adaptive Loop Filter for a second component,
- wherein the method comprises restricting a possible value of each filter coefficient,
- wherein the possible value of each filter coefficient is restricted to any one of zero and values of powers of two represented by a restricted number of bits, wherein said restricted number of bits is lower than a number of bits defined by bit depth, and
- the method further comprising combining the output of the Cross-Component Adaptive Loop Filter with an output of a filter corresponding to a different component.
A device for filtering an image portion using Cross-Component Adaptive Loop Filter, comprising:
- means for acquiring filter coefficients and first component sample values corresponding to samples surrounding a reference sample;
- and
- means for using said filter coefficients and first component sample values for the Cross-Component Adaptive Loop Filter to produce an output of the Cross-Component Adaptive Loop Filter for a second component,
- wherein the device is configured to restrict a possible value of each filter coefficient,
- wherein the possible value of each filter coefficient is restricted to one of zero and values of powers of two represented by a restricted number of bits, wherein said restricted number of bits is lower than a number of bits defined by bit depth, and
- the device being further configured to combine the output of the Cross-Component Adaptive Loop Filter with an output of a filter corresponding to a different component.
A non-transitory computer readable storage medium storing a program for causing a computer to execute method of filtering an image portion using Cross-Component Adaptive Loop Filter, the method comprising:
- acquiring filter coefficients and first component sample values corresponding to samples surrounding a reference sample;
- and
- using said filter coefficients and first component sample values for the Cross-Component Adaptive Loop Filter to produce an output of the Cross-Component Adaptive Loop Filter for a second component,
- wherein the method comprises restricting a possible value of each filter coefficient,
- wherein the possible value of each filter coefficient is restricted to any one of zero and values of powers of two represented by a restricted number of bits, wherein said restricted number of bits is lower than a number of bits defined by bit depth, and
- the method further comprising combining the output of the Cross-Component Adaptive Loop Filter with an output of a filter corresponding to a different component.
Dependencies are inferred from the claim text.