1. A method for antenna pattern assignment for a communication device equipped with a multi-sector antenna including multiple sectors, the multi-sector antenna configured to allow the multi-sector antenna to be used with a plurality of antenna pattern assignments, the method comprising:
sending, by the communication device, a broadcast request using an antenna pattern assignment of the plurality of antenna pattern assignments including one or more sectors of the multiple sectors;
receiving, by the communication device, a response to the broadcast request; and
switching, by the communication device, to a new antenna pattern assignment of the plurality of antenna pattern assignments based on the response,
setting, by the communication device, a timeout depending on a date of sending the broadcast request,
wherein the switching comprises switching, by the communication device, to the new antenna pattern assignment if the response received by the communication device within the timeout is positive.
2. The method according to claim 1, wherein the communication device is further equipped with a receiver coupled to the multi-sector antenna, the receiver configured to control the sending, the receiving, and the switching.
3. The method according to claim 1, wherein the broadcast request is sent to a second communication device, and the response is received from the second communication device.
4. The method according to claim 3, wherein receiving the response comprises receiving a response from the second communication device that is based on a signal strength received at the second communication device and on a signal strength received at the communication device.
5. The method according to claim 1, wherein the broadcast request is sent over a wireless network, and the response is received over the wireless network.
6. The method according to claim 1, wherein the broadcast request includes a first value.
7. The method according to claim 6, wherein the first value is determined based on a received signal strength received by the communication device using the antenna pattern assignment.
8. The method according to claim 1, wherein the switching to the new antenna pattern assignment by the communication device is carried out if the response is a positive response, indicating that the antenna pattern assignment should be switched.
9. A method for antenna pattern assignment for a communication device equipped with a multi-sector antenna including multiple sectors, the multi-sector antenna configured to allow the multi-sector antenna to be used with a plurality of antenna pattern assignments, the method comprising:
receiving, by the communication device using an antenna pattern assignment of the plurality of antenna pattern assignments including one or more sectors of the multiple sectors, a broadcast request comprising a first value;
determining, by the communication device, a second value based on a received signal strength received by the communication device using the antenna pattern assignment;
determining, by the communication device, a response to the broadcast request based on a comparison of the first value and the second value; and
sending, by the communication device, the response,
wherein the first value and the second value are representative of an amount of interference at the communication device.
10. The method according to claim 9, wherein determining the response comprises determining a response indicating whether the antenna pattern assignment should be switched.
11. The method according to claim 9, wherein:
receiving the broadcast request comprises receiving the broadcast request from a separate communication device, and
the first value is based on a signal strength received at the separate communication device.
12. The method according to claim 9, wherein the response sent by the communication device is positive if the communication device determines that the first value is less than the second value.
13. The method according to claim 12, wherein:
when the response sent by the communication device is positive, the communication device sets a timeout, and
the communication device is allowed to adjust said antenna pattern assignment after having sent said response and set said timeout, only when one of two events, including an expiration of the timeout and a reception of a broadcast confirmation packet corresponding to the response sent by the communication device, happens.
14. The method according to claim 9, further comprising:
sending, by the communication device, a separate broadcast request using a current antenna pattern assignment of the plurality of antenna pattern assignments;
receiving, by the communication device, a separate response to the separate broadcast request; and
switching, by the communication device, to a new antenna pattern assignment of the plurality of antenna pattern assignments based on the received separate response.
15. A communication device comprising:
a multi-sector antenna including multiple sectors, the multi-sector antenna configured to allow the multi-sector antenna to be used with a plurality of antenna pattern assignments, wherein the communication device is configured to perform at least the following:
sending a broadcast request using an antenna pattern assignment of the plurality of antenna pattern assignments including one or more sectors of the multiple sectors,
receiving a response to the broadcast request, and
switching to a new antenna pattern assignment of the plurality of antenna pattern assignments based on the response, wherein the communication device is further configured to:
set a timeout depending on a date of sending the broadcast request, and
switch to the new antenna pattern assignment if the response received by the communication device within the timeout is positive.
16. The communication device according to claim 15, further comprising a receiver coupled to the multi-sector antenna, the receiver configured to control the sending, the receiving, and the switching.
17. The communication device according to claim 15 wherein:
the communication device is configured to send the broadcast request to a second communication device, and
the communication device is configured to receive the response from the second communication device.
18. The communication device according to claim 17, wherein receiving the response comprises receiving a response from the second communication device that is based on a signal strength received at the second communication device and on a signal strength received at the communication device.
19. The communication device according to claim 15 wherein:
the communication device is configured to send the broadcast request over a wireless network, and
the communication device is configured to receive the response over the wireless network.
20. The communication device according to claim 15 wherein the communication device is configured to include a first value in the broadcast request.
21. The communication device according to claim 20, wherein the communication device is further configured to determine the first value based on a received signal strength received by the communication device using the antenna pattern assignment.
22. The communication device according to claim 15, wherein the communication device is configured to switch to the new antenna pattern assignment if the response is a positive response, indicating that the antenna pattern assignment should be switched.
23. A communication device comprising:
a multi-sector antenna including multiple sectors, the multi-sector antenna configured to allow the multi-sector antenna to be used with a plurality of antenna pattern assignments, wherein the communication device is configured to perform at least the following:
receiving a broadcast request using an antenna pattern assignment of the plurality of antenna pattern assignments including one or more sectors of the multiple sectors, the broadcast request comprising a first value;
determining a second value based on a received signal strength received by the communication device using the antenna pattern assignment;
determining a response to the broadcast request based on a comparison of the first value and the second value; and
sending the response,
wherein the first value and the second value are representative of an amount of interference at the communication device.
24. The communication device according to claim 23, wherein determining the response comprises determining a response indicating whether the antenna pattern assignment should be switched.
25. The communication device according to claim 23, wherein:
receiving the broadcast request comprises receiving the broadcast request from a separate communication device, and
the first value is based on a signal strength received at the separate communication device.
26. The communication device according to claim 23, wherein the response sent by the communication device is positive if the communication device determines that the first value is less than the second value.
27. The communication device according to claim 26, wherein the communication device is further configured to set a timeout when the response sent by the communication device is positive, and to be allowed to adjust said antenna pattern assignment after having sent said response and set said timeout, only when one of two events, including an expiration of the timeout and a reception of a broadcast confirmation packet corresponding to the response sent by the communication device, happens.
28. The communication device according to claim 23, wherein the communication device is further configured to perform at least the following:
sending, by the communication device, a separate broadcast request using a current antenna pattern assignment of the plurality of antenna pattern assignments;
receiving, by the communication device, a separate response to the separate broadcast request; and
switching, by the communication device, to a new antenna pattern assignment of the plurality of antenna pattern assignments based on the received separate response.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. An apparatus enhancing a contrast, the apparatus comprising:
a first operation part calculating an average and a standard deviation of an input image;
a second operation part calculating an average and a standard deviation of a target image based o n the average and the standard deviation of the input image; and
a mapping part converting a pixel value of the input image by a mapping function generated by receiving the averages and the standard deviations of the input image and the target image from the first operation part and the second operation part, respectively, and outputting a pixel value of an output image.
2. The apparatus as claimed in claim 1, further comprising:
a mapping range designation part providing a mapping part with a lowest upper bound and a highest lower bound with respect to the pixel value of the input image,
wherein the mapping part converts the pixel value of the input image, which exists between the lowest upper bound and the highest lower bound, using the mapping function.
3. The apparatus as claimed in claim 2, wherein the mapping part converts the pixel value of the input image using the mapping function selected from a plurality of mapping functions of respective lower regions formed by dividing a mapping region between the lowest upper bound and the highest lower bound based on the average of the input image.
4. The apparatus as claimed in claim 3, wherein the mapping part selects the mapping function used in converting the pixel value of the input image from the plurality of mapping functions using a following equation:
10
F
(
x
)
=
{
max
(
line
1
,
line
2
)
,
if
,
x
p
a
min
(
line
2
,
line
3
)
,
if
,
x
>
p
a
where, line 1a(xthreshold_low)threshold_low
11
line
2
=
(
b
a
(
x
–
p
a
)
+
p
b
)
,
and
line 3b(xthreshold_high)threshold_high.
5. The apparatus as claimed in claim 2, wherein the mapping function is expressed by a following equation:
12
y
=
(
b
a
)
(
x
–
p
a
)
+
p
b
where, x is the pixel value of the input image, y is the pixel value of the output image, a is the standard deviation of the input image, b is the standard deviation of the target image, a is the average of the input image, and b is the average of the target image.
6. The apparatus as claimed in claim 2, wherein the second operation part calculates the standard deviation of the target image using a following equation:
bm(1k)ka kg(a128)
where, a is the standard deviation of the input image, a is the average of the input image, m is a predetermined variable of a standard deviation, k is a parameter between 0 and 1, and g( ) is a function to determine the parameter k,
wherein the parameter k converges to 0 as the average of the input image approaches 128, which is an average of a Gausian distribution, and the parameter k converges to 1 as the average of the input image is distant from the average of the Gausian distribution.
7. The apparatus as claimed in claim 1, wherein the mapping function is expressed using a following equation:
13
y
=
(
b
a
)
(
x
–
p
a
)
+
p
b
where, x is the pixel value of the input image, y is the pixel value of the output image, a is the standard deviation of the input image, b is the standard deviation of the target image, a is the average of the input image, and b is the average of the target image.
8. The apparatus as claimed in claim 1, wherein the second operation part calculates the standard deviation of the target image using a following equation:
bm(1k)ka
kg(a128)
where, a is the standard deviation of the input image, a is the average of the input image, m is a predetermined variable of a standard deviation, k is a parameter between 0 and 1, and g( ) is a function to determine the parameter k,
wherein the parameter k converges to 0 as the average of the input image approaches 128, which is an average of a Gaussian distribution, and the parameter k converges to 1 as the average of the input image is distant from the average of the Gaussian distribution.
9. A method to enhance a contrast, the method comprising:
calculating an average and a standard deviation of an input image;
calculating an average and a standard deviation of a target image based on the average and the standard deviation of the input image;
generating a mapping function based on the average and the standard deviation of the input image and the average and the standard deviation of the target image; and
converting a pixel value of the input image using the generated mapping function and outputting a pixel value of an output image.
10. The method as claimed in claim 9, prior to converting the pixel value of the input image, the method further comprising:
designating a lowest upper bound and a highest lower bound with respect to the pixel value of the input image,
wherein the generation of the mapping function converts the pixel value of the input image, which exists between the lowest upper bound and the highest lower bound, using the mapping function.
11. The method as claimed in claim 10, wherein the pixel value of the input image is converted by the mapping function selected from a plurality of mapping functions of respective lower regions formed by dividing a mapping region between the lowest upper bound and the highest lower bound based on the average of the input image.
12. The method as claimed in claim 11, wherein the mapping function used in converting the pixel value of the input image from the plurality of mapping functions is selected using a following equation:
14
F
(
x
)
=
{
max
(
line1
,
line2
)
,
if
,
x
p
a
min
(
line2
,
line3
)
,
if
,
x
>
p
a
where, line 1a(xthreshold_low)threshold_low
15
line
2
=
(
b
a
(
x
–
p
a
)
+
p
b
)
,
and
line 3b(xthreshold_high)threshold_high.
13. The method as claimed in claim 10, wherein the mapping function is expressed by a following equation:
16
y
=
(
b
a
)
(
x
–
p
a
)
+
p
b
where, x is the pixel value of the input image, y is the pixel value of the output image, a is the standard deviation of the input image, b is the standard deviation of the target image, a is the average of the input image, and b is the average of the target image.
14. The method as claimed in claim 10, wherein the standard deviation of the target image is calculated using a following equation:
bm(1k)ka kg(a128)
where, a is the standard deviation of the input image, a is the average of the input image, m is a predetermined variable of a standard deviation, k is a parameter between 0 and 1, and g( ) is a function to determine the parameter k,
wherein the parameter k converges to 0 as the average of the input image approaches 128, which is an average of a Gaussian distribution, and the parameter k converges to 1 as the average of the input image is distant from the average of the Gaussian distribution.
15. The method as claimed in claim 9, wherein the mapping function is expressed using a following equation:
17
y
=
(
b
a
)
(
x
–
p
a
)
+
p
b
where, x is the pixel value of the input image, y is the pixel value of the output image, a is the standard deviation of the input image, b is the standard deviation of the target image, a is the average of the input image, and b is the average of the target image.
16. The method as claimed in claim 9, wherein the standard deviation of the target image is calculated using a following equation:
bm(1k)ka kg(a128)
where, a is the standard deviation of the input image, a is the average of the input image, m is a predetermined variable of a standard deviation, k is a parameter between 0 and 1, and g( ) is a function to determine the parameter k,
wherein the parameter k converges to 0 as the average of the input image approaches 128, which is an average of a Gausian distribution, and the parameter k converges to 1 as the average of the input image is distant from the average of the Gausian distribution.