Method for detecting pattern of over-sampling image and an optical information processing apparatus and method using the same
View Patent ↗Provided are a method for detecting a pattern of an over-sampling image and an optical information processing apparatus and method using the same. A method for detecting a pattern from an image of an over-sampled datapage includes: over-sampling the datapage to detect a detection image of the datapage; comparing the detection image and a reference image of over-sampling for the pattern by a covariance; and calculating a pixel of the pattern over-sampled by values of the reference image and the detection image compared by the covariance. Accordingly, data with a specific pattern such as a mark can be detected from an image of an over-sampled datapage, thereby making it possible to increase the data reproduction accuracy, thus making it possible to greatly increase the reliability of reproduced optical data.
1. A method for detecting a pattern from an image of an over-sampled datapage, comprising:
detecting a detection image of the datapage by over-sampling the datapage;
comparing the detection image with a reference image by a covariance, the reference image is an image of over-sampling for the pattern by a covariance; and,
calculating a pixel of the pattern over-sampled by values of the reference image and the detection image compared by the covariance.
2. The method of claim 1 , wherein a step of comparing the detection image with the reference image performs the covariance on the basis of a center pixel of the detection image detected with respect to the over-sampling reference image for the pattern.
3. The method of claim 1 , wherein the value of the reference image and the detection image compared by the covariance is calculated by the following equation;
C
=
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of y i , and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.
4. The method of claim 1 , wherein the value of the reference image and the detection image compared by the covariance is calculated by the following equation;
C
=
k
1
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
k
2
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of y i , k 1 and k 2 are real numbers greater than 0 to amplify the calculation values of the reference image and the detection image, and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.
5. An optical information processing method for detecting an image of a datapage by over-sampling the datapage, comprising:
detecting a detection image of the datapage by over-sampling the datapage,
detecting a mark of the detection image from the detection image by using a covariance;
demodulating the detection image on the basis of the detected mark; and
generating output data by decoding the demodulated detection image.
6. The optical information processing method of claim 5 , wherein the step of detecting the mark comprises:
comparing the detection image with a reference image by a covariance, wherein the reference image is an image of over-sampling for the pattern by a covariance; and
calculating a pixel of the mark over-sampled by values of the reference image and the detection image compared by the covariance.
7. The optical information processing method of claim 6 , wherein the step of comparing the detection image with the reference image performs the covariance on the basis of a center pixel of the detection image detected with respect to the over-sampling reference image for the mark.
8. The optical information processing method of claim 6 , wherein the value of the reference image and the detection image compared by the covariance is calculated by the following equation:
C
=
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of y i , and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.
9. The optical information processing method of claim 6 , wherein the value of the reference image and the detection image compared by the covariance is calculated by the following equation:
C
=
k
1
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
k
2
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of y i , k 1 and k 2 are real numbers greater than 0 to amplify the calculation values of the reference image and the detection image, and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.
10. An optical information processing apparatus comprising:
a light source;
a beam splitter for splitting a beam emitted from the light source into a reference beam and a signal beam;
a spatial light modulator for loading data into the signal beam;
an input data processing unit for encoding the data, modulating the encoded data by modulation code conversion to generate a datapage carrying a mark, and providing the generated datapage to the spatial light modulator;
a detector for over-sampling and detecting the datapage from a reproducing beam reproduced in a recording medium by the reference beam; and
an output data processing unit for comparing and calculating a mark of the datapage image detected by the detector, and the reference image for the mark, by a covariance, and generating output data by demodulating and decoding the detection image using the mark as a reference position.
11. The optical information processing apparatus of claim 10 , wherein the output data processing unit performs the covariance on the basis of a center pixel of the mark in the detection image over-sampled and detected by the detector with respect to the reference image.
12. The optical information processing apparatus of claim 10 , wherein the output data processing unit calculates the covariance for the respective pixels of the detection image and the reference image by the following equation:
C
=
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of y i , and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.
13. The optical information processing apparatus of claim 10 , wherein the output data processing unit calculates the covariance of the detection image and the reference image by the following equation:
C
=
k
1
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
k
2
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of y i , k 1 and k 2 are real numbers greater than 0 to amplify the calculation values of the reference image and the detection image, and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.
14. An optical information processing apparatus comprising:
a light source for emitting a beam for reproduction of a datapage;
a detector for over-sampling and detecting the datapage from a reproducing beam reproduced in a recording medium by the beam; and
an output data processing unit for comparing and calculating a mark of the datapage image detected by the detector and the reference image for the mark by a covariance, and generating output data by demodulating and decoding the detection image using the mark as a reference position.
15. The optical information processing apparatus of claim 14 , wherein the output data processing unit performs the covariance on the basis of a center pixel of the mark in the detection image over-sampled and detected by the detector with respect to the reference image.
16. The optical information processing apparatus of claim 14 , wherein the output data processing unit calculates the covariance for the respective pixels of the detection image and the reference image by the following equation:
C
=
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of Y i , and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.
17. The optical information processing apparatus of claim 14 , wherein the output data processing unit calculates the covariance of the detection image and the reference image by the following equation:
C
=
k
1
∑
i
(
x
i
-
m
x
)
(
y
i
-
m
y
)
+
k
2
∑
i
=
z
(
x
i
-
m
x
)
(
y
i
-
m
y
)
where x i denotes a pixel value of the detection image, m x denotes a mean value of x i , y i denotes a pixel value of the reference image, m y denotes a mean value of y i , k 1 and k 2 are real numbers greater than 0 to amplify the calculation values of the reference image and the detection image, and i=z denotes a center pixel of the image of the datapage among the over-sampled pixels of the detection image.