System and method for video coding
An encoder includes circuitry and memory coupled to the circuitry. The circuitry, in operation, generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component, generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component, and clips the second coefficient value. The circuitry generates a third coefficient value by adding the first coefficient value to the clipped second coefficient value, and clips the third coefficient value. The circuitry encodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.
1. An encoder, comprising:
circuitry; and
memory coupled to the circuitry;
wherein the circuitry, in operation:
generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
clips the first coefficient value to be within a range of −2 7 to 2 7 −1;
sets the clipped first coefficient value to zero in response to the first coefficient value being less than 64;
generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clips the second coefficient value;
generates a third coefficient value by adding the clipped first coefficient value to the clipped second coefficient value;
clips the third coefficient value; and
encodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.
2. The encoder of claim 1 , wherein, the first reconstructed image sample is located adjacent to the second reconstructed image sample.
3. A decoder, comprising:
circuitry; and
memory coupled to the circuitry;
wherein the circuitry, in operation:
generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
clips the first coefficient value to be within a range of −2 7 to 2 7 −1;
sets the clipped first coefficient value to zero in response to the first coefficient value being less than 64;
generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clips the second coefficient value;
generates a third coefficient value by adding the clipped first coefficient value to the clipped second coefficient value;
clips the third coefficient value; and
decodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.
4. The decoder of claim 3 , wherein, the first reconstructed image sample is located adjacent to the second reconstructed image sample.
5. A decoding method, comprising:
generating a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
clipping the first coefficient value to be within a range of −2 7 to 2 7 −1;
setting the clipped first coefficient value to zero in response to the first coefficient value being less than 64;
generating a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clipping the second coefficient value;
generating a third coefficient value by adding the clipped first coefficient value to the clipped second coefficient value;
clipping the third coefficient value; and
decoding a third reconstructed image sample of the chroma component using the clipped third coefficient value.
6. An encoder, comprising:
circuitry; and
memory coupled to the circuitry;
wherein the circuitry, in operation:
generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
sets the first coefficient value to zero in a case where the first coefficient less than 64;
generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clips the second coefficient value;
generates a third coefficient value by adding the first coefficient value to the clipped second coefficient value;
clips the third coefficient value; and
encodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.
7. A decoder, comprising:
circuitry; and
memory coupled to the circuitry;
wherein the circuitry, in operation:
generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
sets the first coefficient value to zero in a case where the first coefficient less than 64;
generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clips the second coefficient value;
generates a third coefficient value by adding the first coefficient value to the clipped second coefficient value;
clips the third coefficient value; and
decodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.
8. An encoding method, comprising:
generating a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
setting the first coefficient value to zero in a case where the first coefficient less than 64;
generating a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clipping the second coefficient value;
generating a third coefficient value by adding the first coefficient value to the clipped second coefficient value;
clipping the third coefficient value; and
encoding a third reconstructed image sample of the chroma component using the clipped third coefficient value.
9. A decoding method, comprising:
generating a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
setting the first coefficient value to zero in a case where the first coefficient less than 64;
generating a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clipping the second coefficient value;
generating a third coefficient value by adding the first coefficient value to the clipped second coefficient value;
clipping the third coefficient value; and
decoding a third reconstructed image sample of the chroma component using the clipped third coefficient value.
10. The encoder of claim 1 , wherein
the second coefficient clipped to be within another range, and
the another range is indicated by a clip parameter that includes a first clip value that is a lower value of the another range, and a second clip value that is an upper value of the another range.
11. The encoder of claim 1 , wherein
the second coefficient clipped to be within another range,
the another range is indicated by a clip parameter that includes a clip value,
a negative value of the clip a lower value of the another range, and
a positive value of the clip an upper value of the another range.
12. An encoder, comprising:
circuitry; and
memory coupled to the circuitry;
wherein the circuitry, in operation:
generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
clips the first coefficient value to be within a first range of −2 7 to 2 7 −1;
generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clips the second coefficient value to be within a second range, the second range being indicated by a clip parameter that includes a first clip value that is a lower value of the second range, and a second clip value that is an upper value of the second range;
generates a third coefficient value by adding the clipped first coefficient value to the clipped second coefficient value;
clips the third coefficient value; and
encodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.
13. An encoder, comprising:
circuitry; and
memory coupled to the circuitry;
wherein the circuitry, in operation:
generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component;
clips the first coefficient value to be within a first range of −2 7 to 2 7 −1;
generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component;
clips the second coefficient value to be within a second range, the second range being indicated by a clip parameter that includes a clip value, a negative value of the clip value being a lower value of the second range, a positive value of the clip value being an upper value of the second range;
generates a third coefficient value by adding the clipped first coefficient value to the clipped second coefficient value;
clips the third coefficient value; and
encodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.