FILTERS FOR MOTION COMPENSATION INTERPOLATION WITH REFERENCE DOWN-SAMPLING
The present disclosure provides systems and methods for processing video content using motion compensation interpolation. The methods include: in response to a target picture and a reference picture having different resolutions, applying a band-pass filter to the reference picture, to perform a motion compensated interpolation with reference down-sampling to generate a reference block; and encoding or decoding a block of the target picture using the reference block.
1 . A video decoding method, comprising:
decoding a bitstream to reconstruct a reference picture; and
applying one or more filters to the reference picture,
wherein the applying of the one or more filters generates a chroma sample at a fractional sample position, and
wherein the one or more filters comprise a 4-tap filter that has one or more sets of coefficients, wherein each set of coefficients is associated with a fractional sample position, and the one or more sets of coefficients comprise a first set of coefficients {17, 30, 17, 0}.
2 . The method according to claim 1 , wherein the one or more sets of coefficients comprise a second set of coefficients {17, 30, 18, −1}.
3 . The method according to claim 1 , wherein the one or more sets of coefficients comprise a third set of coefficients {16, 30, 18, 0}.
4 . The method according to claim 1 , wherein the one or more sets of coefficients comprise a fourth set of coefficients {15, 30, 18, 1}.
5 . The method according to claim 1 , wherein the one or more sets of coefficients comprise a fifth set of coefficients {14, 30, 18, 2}.
6 . The method according to claim 1 , wherein the one or more sets of coefficients comprise a sixth set of coefficients {13, 29, 19, 3}.
7 . The method according to claim 1 , wherein the one or more sets of coefficients comprise a seventh set of coefficients {12, 29, 20, 3}.
8 . The method according to claim 1 , further comprising:
decoding the plurality of coefficients from at least one of a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), an Adaptation Parameter Set (APS), or a slice header.
9 . The method according to claim 1 , wherein applying the one or more filters comprises:
selecting the one or more filter, based on a sampling ratio of the reference picture.
10 . A video encoding method, comprising:
encoding a target picture by applying one or more filters to a reference picture,
wherein the applying of the one or more filters generates a chroma sample at a fractional sample position, and
wherein the one or more filters comprise a 4-tap filter that has one or more sets of coefficients, wherein each set of coefficients is associated with a fractional sample position, and the one or more sets of coefficients comprise a first set of coefficients {17, 30, 17, 0}.
11 . The method according to claim 10 , wherein the one or more sets of coefficients comprise a second set of coefficients {17, 30, 18, −1}.
12 . The method according to claim 10 , wherein the one or more sets of coefficients comprise a third set of coefficients {16, 30, 18, 0}.
13 . The method according to claim 10 , wherein the one or more sets of coefficients comprise a fourth set of coefficients {15, 30, 18, 1}.
14 . The method according to claim 10 , wherein the one or more sets of coefficients comprise a fifth set of coefficients {14, 30, 18, 2}.
15 . The method according to claim 10 , wherein the one or more sets of coefficients comprise a sixth set of coefficients {13, 29, 19, 3}.
16 . The method according to claim 10 , wherein the one or more sets of coefficients comprise a seventh set of coefficients {12, 29, 20, 3}.
17 . The method according to claim 10 , further comprising:
encoding the plurality of coefficients into at least one of a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), an Adaptation Parameter Set (APS), or a slice header.
18 . The method according to claim 10 , wherein applying the one or more filters comprises:
selecting the one or more filter, based on a sampling ratio of the reference picture.
19 . A method of storing a bitstream of a video, the method comprising:
generating the bitstream by applying one or more filters to a reference picture; and
storing the bitstream in a non-transitory computer-readable medium,
wherein the applying of the one or more filters generates a chroma sample at a fractional sample position, and
wherein the one or more filters comprise a 4-tap filter that has one or more sets of coefficients, wherein each set of coefficients is associated with a fractional sample position, and the one or more sets of coefficients comprise a first set of coefficients {17, 30, 17, 0}.
20 . The method according to claim 19 , wherein the one or more sets of coefficients comprise a second set of coefficients {17, 30, 18, −1}.