Devices and methods for sample adaptive offset coding and/or selection of edge offset parameters

1. A method for decoding an encoded block of an encoded video frame, the method comprising:

decoding the encoded block using a sample adaptive offset compensated value generated by applying an offset value to a current pixel value of the encoded block, the sample adaptive offset compensated value limited by an interpolated pixel value generated using vertically deblocked left and right neighboring pixel values of the current pixel value.

2. The method of claim 1 , further comprising:

determining an edge offset type based on a codeword signaled within an encoded bitstream including the encoded video frame;

selecting an edge offset sub-class for the current pixel value, the edge offset sub-class corresponding to the edge offset type; and

determining the offset value based on the edge offset sub-class.

3. The method of claim 2 , wherein the edge offset sub-class is selected based on comparisons between the current pixel value and each of the left and right neighboring pixel values.

4. The method of claim 2 , wherein a different edge offset sub-class is selected for the current pixel value responsive to determining that the current pixel value is different from a weighted combination of the left and right neighboring pixel values.

5. The method of claim 2 , wherein the edge offset type is not signaled within the encoded bitstream when an offset applied for encoding the encoded block is negative.

6. The method of claim 1 , wherein the left and right neighboring pixel values are averaged to generate the interpolated pixel value.

7. An apparatus for decoding an encoded block of an encoded video frame, the apparatus comprising:

a processor configured to execute instructions stored in a non-transitory storage medium to:

decode the encoded block using a sample adaptive offset compensated value generated by applying an offset value to a current pixel value of the encoded block, the sample adaptive offset compensated value limited by an interpolated pixel value generated using vertically deblocked left and right neighboring pixel values of the current pixel value.

8. The apparatus of claim 7 , wherein the instructions include instructions to:

determine an edge offset type based on a codeword signaled within an encoded bitstream including the encoded video frame;

select an edge offset sub-class for the current pixel value, the edge offset sub-class corresponding to the edge offset type; and

determine the offset value based on the edge offset sub-class.

9. The apparatus of claim 8 , wherein the edge offset sub-class is selected based on comparisons between the current pixel value and each of the left and neighboring pixel values.

10. The apparatus of claim 8 , wherein a different edge offset sub-class is selected for the current value pixel responsive to a determination that the current pixel value is different from a weighted combination of the left and right neighboring pixel values.

11. The apparatus of claim 8 , wherein the edge offset type is not signaled within the encoded bitstream when an offset applied for encoding the encoded block is negative.

12. The apparatus of claim 7 , wherein the left and right neighboring pixel values are averaged to generate the interpolated pixel value.

13. A method, comprising:

applying, to a current pixel value, an offset value limited by a weighted combination of vertically deblocked left and right neighboring pixel values of the current pixel value.

14. The method of claim 13 , further comprising:

encoding a block including the current pixel value using a sample adaptive offset compensated value generated responsive to the applying.

15. The method of claim 13 , further comprising:

decoding an encoded block including the current pixel value using a sample adaptive offset compensated value generated responsive to the applying.

16. The method of claim 13 , wherein the offset value is determined based on an edge offset sub-class for the current pixel value.

17. The method of claim 16 , wherein the edge offset sub-class is selected based on a codeword representing an edge offset type within an encoded bitstream including an encoded block, the encoded block including the current pixel value.

18. The method of claim 17 , wherein the encoded bitstream does not include codewords representing edge offset types for blocks encoded using a negative offset.