Sampled data digital filtering system
View Patent ↗A digital filtering system for filtering sample data includes a delay network for delaying input sample data to provide multiple delayed sample data outputs. The filtering system also includes a filter network represented by a decomposed coefficient weighting matrix for processing the delayed sample data outputs. A processor produces a filtered output by computing a weighted product summation of the delayed sample data outputs and the coefficient weighting matrix. The decomposed coefficient weighting matrix is derived by factoring a first coefficient weighting matrix with a common row factor and/or sparse matrix or by factoring based on matrix row or column symmetry.
1. A digital filter for filtering sample data, comprising:
a delay network for delaying input sample data to provide a plurality of delayed sample data outputs;
a filter network representable by a decomposed coefficient weighting matrix for processing said delayed sample data outputs; and
a processor for producing a filtered output by computing a weighted product summation of said delayed sample data outputs and said coefficient weighting matrix, said processor being responsive to a sample spatial position index signal in producing said filtered output.
2. A digital filter according to claim 1 , wherein
said decomposed coefficient weighting matrix comprises a structurally factored matrix.
3. A digital filter according to claim 2 , wherein
said structurally factored matrix employs a factor derived based on a property including at least one of, (a) coefficient matrix row symmetry, and (b) coefficient matrix column symmetry.
4. A digital filter according to claim 1 , wherein
said decomposed coefficient weighting matrix is derived by at least one of (a) factoring a first coefficient weighting matrix with a common row factor, and (b) factoring a first coefficient weighting matrix based on at least one of, (i) coefficient matrix row symmetry, and (ii) coefficient matrix column symmetry.
5. A digital filter according to claim 1 , wherein
said decomposed coefficient weighting matrix is derived by factoring a first coefficient weighting matrix using a sparse matrix.
6. A digital filter according to claim 1 , wherein
said decomposed coefficient weighting matrix represents a multiple input, multiple output, filter network.
7. A digital filter according to claim 1 , including
an interpolation network for interpolating sample data to provide said input sample data.
8. A digital filter according to claim 1 , wherein
said processor includes a factor combiner for deriving a weighted sum of factors representing a linear transform process.
9. A digital filter according to claim 1 , wherein
said decomposed coefficient weighting matrix exhibits the form
[
0
0
3
0
-
1
4
-
2
-
1
1
-
1
-
1
1
]
3
.
10. A digital filter according to claim 1 , wherein
said digital filter provides the function
H
(
z
)
=
[
1
μ
μ
2
]
·
[
0
0
3
0
-
1
4
-
2
-
1
1
-
1
-
1
1
]
3
·
[
1
z
-
1
z
-
2
z
-
3
]
where u is a sample spatial position representative signal and z represents an input sample.
11. A digital filter according to claim 1 , wherein
said decomposed coefficient weighting matrix exhibits the form
[
6
58
58
6
23
59
-
59
-
23
31
-
31
-
31
31
16
-
48
48
-
16
]
128
.
12. A digital filter according to claim 1 , wherein
said digital filter provides the following function, where u is a sample spatial position representative signal and z presents an input sample
H
(
z
)
=
[
1
μ
μ
2
μ
3
]
[
1
2
0
3
64
0
0
1
0
23
128
0
0
31
128
0
0
0
0
1
8
]
·
[
0
1
1
0
0
1
-
1
0
1
-
1
-
1
1
1
-
3
3
-
1
]
·
[
1
z
-
1
z
-
2
z
-
3
]
13. A method for filtering sample data, comprising the steps of:
delaying input sample data to provide a plurality of delayed sample data outputs;
processing said delayed sample data outputs using a filter network represented by a structurally factored coefficient weighting matrix, said structurally factored matrix comprising a coefficient weighting matrix employing factors derived based on a property including at least one of, (a) coefficient matrix row symmetry, and (b) coefficient matrix column symmetry; and
producing a filtered output by computing a weighted product summation of said delayed sample data outputs and said coefficient weighting matrix.
14. A method for filtering sample data, comprising the steps of:
delaying input sample data to provide a plurality of delayed sample data outputs;
processing said delayed sample data outputs using a filter network represented by a structurally factored coefficient weighting matrix, said structurally factored matrix being derived by at least one of (a) factoring a first coefficient weighting matrix with a common row factor, and (b) factoring a first coefficient weighting matrix based on a property including at least one of, (i) coefficient matrix row symmetry, and (ii) coefficient matrix column symmetry; and
producing a filtered output by computing a weighted product summation of said delayed sample data outputs and said coefficient weighting matrix.
15. A method for filtering sample data, comprising the steps of:
delaying input sample data to provide a plurality of delayed sample data outputs;
processing said delayed sample data outputs using a filter network represented by a structurally factored coefficient weighting matrix, said structurally factored matrix comprising a decomposed coefficient weighting matrix derived by factoring a first coefficient weighting matrix using a sparse matrix; and
producing a filtered output by computing a weighted product summation of said delayed sample data outputs and said coefficient weighting matrix.
16. A method for filtering sample data, comprising the steps of:
delaying input sample data to provide a plurality of delayed sample data outputs;
processing said delayed sample data outputs using a filter network using a coefficient weighting matrix comprising,
[
0
0
3
0
-
1
4
-
2
-
1
1
-
1
-
1
1
]
3
;
and
producing a filtered output by computing a weighted product summation of said delayed sample data outputs and said coefficient weighting matrix.
17. A method for filtering sample data, comprising the steps of:
delaying input sample data to provide a plurality of delayed sample data outputs;
processing said delayed sample data outputs using a filter network using a coefficient weighting matrix comprising,
[
6
58
58
6
23
59
-
59
-
23
31
-
31
-
31
31
16
-
48
48
-
16
]
128
;
and
producing a filtered output by computing a weighted product summation of said delayed sample data outputs and said coefficient weighting matrix.