Method for processing a digital file notably of the image, video and/or audio type
View Patent ↗A method for processing a digital file of the images, video and/or audio type which comprises a phase for putting into line per color layer and/or per audio channel, digital data of any audio, image and video file, a compression phase using algorithm in which each compressed value VC n of position N is obtained by subtracting from the value Vn of same position N of the original file, a predetermined number of successive compressed values (VC n-1 , VC n-2 , . . . ) calculated previously, and a restoration phase using an algorithm in which each restored value VDn of position N is obtained by adding to the value VC n , of the same position of the compressed file, a predetermined number of successive compressed values (VC n-1 , VC n-2 , . . . ).
1. A method for processing a digital file notably of the image, video and/or audio type, comprising
a phase for putting into line per color layer and/or per audio channel, digital data of any audio, image and video file, a compression phase in which the values of said file are successively compressed by means of an algorithm in which each compressed value (VC N ) of row N is obtained by subtracting from the value V N of same row N of the original file, a predetermined number of successive compressed values (VC N-1 , VC N-2 , . . . ) calculated previously, and
a restoration phase in which each of the values of the compressed file is brought back to a value close to the corresponding value of the original file by means of an algorithm in which each restored value (VD N ) of row N is obtained by adding to the value VC N , of same row of the compressed file, a predetermined number of successive restored values (VC N-1 , VC N-2 , . . . ).
2. The method according to claim 1 , wherein the compression algorithm is of the form:
VC 1 =rounded to the closest unit[( V 1 −h )× k]
VC 2 =rounded to the closest unit[( V 2 −VC 1 −h )× k]
VC 3 =rounded to the closest unit[( V 3 −VC 2 −VC 1 −h )× k]
. . .
VC N =rounded to the closest unit[( V N −VC N-1 −VC N-2 −h )× k] formula 1
a relationship in which,
VC N is the value of row N of compressed file
VC N-1 is the previously calculated value of row N−1 of the compressed file
VC N-2 is the previously calculated value of row N−2 of the compressed file
V N is the value of row N of the original file
k and h are compression coefficients varying according to the sought compression level.
3. The method according to claim 2 , wherein:
for a level 1 k=−⅓, h=1
for a level 2 k=−⅕, h=3
for a level 3 k=− 1/7, h=10.
4. The method according to claim 1 , wherein the restoration algorithm is of the form:
VD
1
=
1
k
VC
1
+
h
VD
2
=
1
k
VC
2
+
VC
1
+
h
VD
3
=
1
k
VC
3
+
VC
2
+
VC
1
+
h
…
VD
N
=
1
k
VC
N
+
VC
-
1
+
VC
N
-
2
+
h
formula
2
a relationship in which:
VD N is the restored value of row N
VC N-1 is the compressed value of row N−1
VC N-2 is the compressed value of row N−2.
5. The method according to claim 1 for processing a file including at least two sets of values, further comprising:
a preliminary phase for selecting from both sets, the one for which the average deviation separating the digital values of this set is larger than the average deviation which separates the values of the other set,
a phase for compressing the selected set by using a compression algorithm of the type of that described earlier for example of type:
VC N =rounded to the closest unit[( V N −VC N-1 −VC N-2 −h )× k] formula 1
a phase for compressing the second set, by means of a compression algorithm which involves for calculating each of the values
VC′ 1 =rounded to the closest unit[ V′ 1 −h )× k]
VC′ 2 =rounded to the closest unit[ V′ 2 −VC 1 −h )× k]
VC′ 3 =rounded to the closest unit[ V′ 3 −VC 2 −VC 1 −h )× k]
. . .
VC′ N =rounded to the closest unit [ V′ N −VC N-1 −VC N-2 −h )× k] formula 3
a formula in which:
V′ N is the value of row N of the second file
VC N-1 is the compressed value of row N−1 of the first file
VC N-2 is the compressed value of row N−2 of the first file.
6. The method according to claim 5 , wherein the restoration of the values of the aforesaid first set is carried out according to the restoration algorithm:
VD
N
=
1
k
VC
N
+
VC
N
-
1
+
VC
N
-
2
+
h
formula
2
VDN being the restored value of row N of the first file,
and in that the restoration of values of the second file is carried out according to the algorithm:
VD
1
′
=
1
k
VC
1
′
+
h
VD
2
′
=
1
k
VC
2
′
+
VC
1
+
h
VD
3
′
=
1
k
VC
3
′
+
VC
2
+
VC
1
+
h
VD
N
′
=
1
k
VC
N
′
+
VC
N
-
1
+
VC
N
-
2
+
h
formula
4
VD′ N being the restored value of row N of the second file.
7. The method according to claim 1 , further comprising:
a compression phase using an algorithm of the form:
VC
1
=
rounded
to
the
closest
unit
[
i
-
(
V
1
-
i
)
0
,
1
i
]
VC
2
=
rounded
to
the
closest
unit
[
i
-
(
V
2
-
VC
1
-
i
)
0
,
1
i
]
VC
3
=
rounded
to
the
closest
unit
[
i
-
(
V
3
-
VC
2
-
VC
1
-
i
)
0
,
1
i
]
…
VC
N
=
rounded
to
the
closest
unit
[
i
-
(
VN
-
VCN
-
1
-
·
VCN
-
2
-
i
)
0
,
1
i
]
formula
5
i=a coefficient depending on the sought compression level with i>I
and
a restoration phase using an algorithm of the form:
VD 1 =−0,1 iVC j +0,1 i 2 +i =(−0,1 VC 1 +0,1 i+ 1)
VD 2 =i (−0,1 VC 2 +0,1 i+ 1)+ VC 1
VD 3 =i (−0,1 VC 3 +0,1 i+ 1)+ VC 2 +VC 1
. . .
VD N =i (−0,1 VC N +0,1 i+ 1)+ VC N-1 +VC N-2 formula 6.