U.S. patent application number 14/058831 was filed with the patent office on 2014-02-06 for system operative to adaptively select an image sensor for decodable indicia reading.
This patent application is currently assigned to Hand Held Products, Inc.. The applicant listed for this patent is Hand Held Products, Inc.. Invention is credited to James Timothy Sauerwein, JR..
Application Number | 20140034734 14/058831 |
Document ID | / |
Family ID | 46576520 |
Filed Date | 2014-02-06 |
United States Patent
Application |
20140034734 |
Kind Code |
A1 |
Sauerwein, JR.; James
Timothy |
February 6, 2014 |
SYSTEM OPERATIVE TO ADAPTIVELY SELECT AN IMAGE SENSOR FOR DECODABLE
INDICIA READING
Abstract
A decodable indicia reading system can be provided for use in
locating and decoding a bar code symbol represented within a frame
of image data. The system can comprise a central processing unit
(CPU), a memory communicatively coupled to the CPU, and two or more
image sensors communicatively coupled to the CPU or to the memory.
The system can be configured to select an image sensor for indicia
reading by cycling through available image sensors to detect an
image sensor suitable for an attempted indicia reading operation by
comparing a measured parameter value to a pre-defined
sensor-specific threshold value. The system can be further
configured to select the first suitable or the best suitable image
sensor for the attempted decodable indicia reading operation based
upon the comparison result. The system can be further configured to
notify the system operator which image sensor has been selected.
The system can be further configured to obtain a decodable indicia
image by the selected image sensor.
Inventors: |
Sauerwein, JR.; James Timothy;
(Charlotte, NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hand Held Products, Inc. |
Fort Mill |
SC |
US |
|
|
Assignee: |
Hand Held Products, Inc.
Fort Mill
SC
|
Family ID: |
46576520 |
Appl. No.: |
14/058831 |
Filed: |
October 21, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13018058 |
Jan 31, 2011 |
8561903 |
|
|
14058831 |
|
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Current U.S.
Class: |
235/455 ;
235/454; 235/469; 235/472.01 |
Current CPC
Class: |
G06K 7/1439 20130101;
G06K 7/10722 20130101; G06K 7/1408 20130101 |
Class at
Publication: |
235/455 ;
235/472.01; 235/469; 235/454 |
International
Class: |
G06K 7/10 20060101
G06K007/10; G06K 7/14 20060101 G06K007/14 |
Claims
1. A decodable indicia reading system comprising: a central
processing unit (CPU); a memory communicatively coupled to said
CPU; two or more image sensors communicatively coupled to one of:
said memory, said CPU; a hand held housing in which the two or more
image sensors are disposed; wherein said system is configured to
select a suitable image sensor for an indicia reading operation by
cycling through said two or more image sensors and comparing a
measured value of a parameter to a pre-defined sensor-specific
threshold value for each of said two or more image sensors; wherein
said system is further configured to notify an operator of said
system about selecting said suitable image sensor; and wherein said
system is further configured to obtain a decodable indicia image by
said suitable image sensor.
2. The system of claim 1, wherein said suitable image sensor is the
best suitable image sensor for said indicia reading operation.
3. The system of claim 1, wherein said parameter is provided by one
of: a decoding time, a required exposure time, an ambient light
intensity, and a signal to noise ratio.
4. The system of claim 1, wherein at least one image sensor of said
two or more image sensors is provided by a color image sensor.
5. The system of claim 1, wherein at least one image sensor of said
two or more image sensors is provided by a monochrome image
sensor.
6. The method of claim 1, wherein at least one image sensor of said
two or more image sensors is provided by a hybrid monochrome and
color image sensor.
7. The system of claim 1, wherein said first image sensor of said
two or more image sensors is configured to provide a first image
resolution, and said second image sensor of said two or more image
sensors is configured to provide a second image resolution; and
wherein said second image resolution is greater than said first
image resolution.
8. The system of claim 1, wherein said first image sensor of the
two or more image sensors is configured to provide a first signal
to noise ratio, and said second image sensor of the two or more
image sensors is configured to provide a second signal to noise
ratio; and wherein said second signal to noise ratio is greater
than said first signal to noise ratio.
9. The system of claim 1 further configured to notify said operator
by at least one of: an audible signal, a visual signal, a tactile
signal.
10. A method for adaptively selecting an image sensor for reading
decodable indicia by a decodable indicia reading system including
two or more image sensors that are disposed within a hand held
housing, said method comprising the steps of: (i) for each image
sensor of said two or more image sensors determining whether said
image sensor is suitable for an attempted indicia reading operation
by comparing a measured value of a parameter to an image
sensor-specific pre-defined value; (ii) performing at least one of:
(a) conditionally branching to step (iii) upon detecting a second
image sensor for which said step of comparing yields a pre-defined
result, and (b) selecting a second image sensor for which said step
of comparing yields the best result among all image sensors of said
two or more image sensors; (iii) obtaining a decodable indicia
image by said second image sensor.
11. The method of claim 10, wherein said step (iii) is preceded by
a step of notifying an operator of said decodable indicia reading
system about said second image sensor having been selected for an
attempted indicia reading operation
12. The method of claim 10, wherein said parameter is provided by
one of: a decoding time, a required exposure time, an ambient light
intensity, and a signal to noise ratio.
13. The method of claim 10, wherein at least one image sensor of
said two or more image sensors is provided by a color image
sensor.
14. The method of claim 10, wherein at least one image sensor of
said two or more image sensors is provided by a monochrome image
sensor.
15. The method of claim 10, wherein at least one image sensor of
said two or more image sensors is provided by a hybrid monochrome
and color image sensor.
16. The method of claim 10, wherein said first image sensor of said
two or more image sensors is configured to provide a first image
resolution, and said second image sensor of said two or more image
sensors is configured to provide a second image resolution; and
wherein said second image resolution is greater than said first
image resolution.
17. The method of claim 10, wherein said first image sensor of the
two or more image sensors is configured to provide a first signal
to noise ratio, and said second image sensor of the two or more
image sensors is configured to provide a second signal to noise
ratio; and wherein said second signal to noise ratio is greater
than said first signal to noise ratio.
18. The method of claim 11, wherein said step of notifying is
performed by at least one of: an audible signal, a visual signal, a
tactile signal.
19. A method for adaptively selecting an image sensor for reading
decodable indicia by a decodable indicia reading system including
two or more image sensors, said method comprising the steps of: (i)
obtaining a decodable indicia image by a first image sensor; (ii)
attempting to locate and decode a decodable indicia within said
decodable indicia image; (iii) conditionally, upon said step (ii)
failure, performing the following steps (iv)-(vii): (iv) measuring
a value of a parameter for said decodable indicia image; (v) for
each image sensor of said two or more image sensors excluding said
first image sensor, determining whether said image sensor is
suitable for an attempted indicia reading operation by comparing
said value to an image sensor-specific pre-defined value; (vi)
performing at least one of: (a) conditionally branching to step
(vii) upon detecting a second image sensor for which said step of
comparing yields a pre-defined result, and (b) selecting a second
image sensor for which said step of comparing yields the best
result among all image sensors of said two or more image sensors;
(vii) obtaining a decodable indicia image by said second image
sensor.
20. The method of claim 19, wherein said step (iv) is preceded by a
step of notifying an operator of said decodable indicia reading
system about said second image sensor having been selected for an
attempted indicia reading operation
21. The method of claim 19, wherein said parameter is provided by
one of: a decoding time, a required exposure time, an ambient light
intensity, and a signal to noise ratio.
22. The method of claim 19, wherein at least one image sensor of
said two or more image sensors is provided by a color image
sensor.
23. The method of claim 19, wherein at least one image sensor of
said two or more image sensors is provided by a monochrome image
sensor.
24. The method of claim 19, wherein at least one image sensor of
said two or more image sensors is provided by a hybrid monochrome
and color image sensor.
25. The method of claim 19, wherein said first image sensor of said
two or more image sensors is configured to provide a first image
resolution, and said second image sensor of said two or more image
sensors is configured to provide a second image resolution; and
wherein said second image resolution is greater than said first
image resolution.
26. The method of claim 19, wherein said first image sensor of the
two or more image sensors is configured to provide a first signal
to noise ratio, and said second image sensor of the two or more
image sensors is configured to provide a second signal to noise
ratio; and wherein said second signal to noise ratio is greater
than said first signal to noise ratio.
27. The method of claim 20, wherein said step of notifying is
performed by at least one of: an audible signal, a visual signal, a
tactile signal.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to image data processing in
general and specifically to an image data processing system
comprising two or more image sensors.
BACKGROUND OF THE PRIOR ART
[0002] Some of commercially available decodable indicia reading and
decoding systems (portable and stationary data terminals, and other
data collection systems) include a digital color camera and a
dedicated monochrome image sensor intended for bar code reading.
However, such systems lack the image sensor selection functionality
for performing decodable indicia reading.
[0003] Therefore, a need exists to provide a system and method for
selecting an image sensor for decodable indicia reading.
SUMMARY OF THE INVENTION
[0004] In one embodiment, there is provided a decodable indicia
reading system comprising a central processing unit (CPU), a memory
communicatively coupled to the CPU, and two or more image sensors
communicatively coupled to the memory and/or the CPU. The system
can be configured to select an image sensor for indicia reading by
cycling through available image sensors to detect an image sensor
suitable for an attempted indicia reading operation by comparing a
measured parameter value to a pre-defined sensor-specific threshold
value. The system can be further configured to select the first
suitable or the best suitable image sensor for the attempted
decodable indicia reading operation based upon the comparison
result. The system can be further configured to notify the system
operator which image sensor has been selected. The system can be
further configured to obtain a decodable indicia image by the
selected image sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The features described herein can be better understood with
reference to the drawings described below. The drawings are not
necessarily to scale, emphasis instead generally being placed upon
illustrating the principles of the invention. In the drawings, like
numerals are used to indicate like parts throughout the various
views.
[0006] FIG. 1 is a block diagram illustrating exemplary components
of one embodiment of the decodable indicia reading system according
to the invention;
[0007] FIG. 2 is a system block diagram illustrating exemplary
components of one embodiment of the data collection system
according to the invention;
[0008] FIG. 3 illustrates a flowchart of one embodiment of a method
for adaptively selecting an image sensor for reading decodable
indicia by a decodable indicia reading system according to the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0009] In one embodiment, there is provided a decodable indicia
reading system operative to adaptively select an image sensor. A
block diagram illustrating exemplary components of the decodable
indicia reading system according to the invention is shown in FIG.
1. In one embodiment, the decodable indicia reading system 100 can
include a CPU 1060 in communication with a memory 1085 via a system
bus 1500. The memory 1085 can include one or more of a volatile
memory 1080, e.g., RAM, a non-volatile memory 1082 e.g., ROM and a
long-term storage memory 1084, e.g., a hard drive, a CD, a floppy
and/or a flash memory device. Memory 1080, memory 1082, and memory
1084 can be regarded as recording medium.
[0010] In one aspect, the decodable indicia reading system 100 can
include a trigger 1110, a pointer mechanism 1120, a keyboard 1130,
and a display 1140. Each of the devices 1110, 1120, 1130, and 1140
can be communicatively coupled to system bus 1500 for communicating
with the CPU 1060 via respective interfaces 1108, 1118, 1128, and
1138.
[0011] In another aspect, the decodable indicia reading system 100
can include a communication interface 1210 for communicating with
external computers. The communication interface can be provided by
a wire line communication interface (e.g, an Ethernet interface or
a USB interface) or a wireless communication interface (e.g., an
IEEE 802.11-compliant wireless communication interface or a
Bluetooth interface). The system 100 can include more than one or
more communication interfaces 1210.
[0012] In one embodiment, the decodable indicia reading system 100
can be provided by a portable data terminal (e.g., bar code reading
terminal). In another embodiment, the decodable indicia reading
system 100 can be provided by a stationary data terminal (e.g., a
cash register). A skilled artisan would appreciate the fact that
other form factors and applications of the decodable indicia
reading system 100 are within the spirit and the scope of the
invention.
[0013] In another aspect, the decodable indicia reading system 100
can be part of a data collection system, e.g., a data collection
system 10000 shown in FIG. 2. At a local facility 1000 there can be
disposed a plurality of imaging reading terminals configured in
accordance with system 100. In one example, local facility 1000 can
be provided by a retail store. In another example, local facility
1000 can be provided by a warehouse. In another example, local
facility 1000 can be provided by a health care facility. In one
example, local facility 1000 can be provided by a personal
residence. At local facility 1000 there can be included server 200
external to data terminal 100. In a further aspect, terminals 100
and server 200 can be in communication with a remote server 400 via
network 300 which can be e.g., a TCP/IP network. Server 400 can be
disposed at a facility 4000 remote from facility 1000. In a further
aspect, one or more client computers 500 can also be included in
the data collection system 10000. Client computer 500 in one
embodiment can be provided by e.g., a desktop personal computer and
laptop personal computer a smart phone e.g., IPHONE by Apple
Computers, Inc., BLACKBERRY STORM by Research in Motion
Limited.
[0014] By virtue of their including at least a central processing
unit (CPU) 1060 in combination with a memory 1085, each of the data
terminal 100, server 200, and client computer 500 of the data
collection system 10000 can be regarded as a "computer." Each
computer of the data collection system 10000 can be configured in
accordance with the TCP/IP protocol so that each computer of the
data collection system 10000 can be in IP network communication
with each other computer of the data collection system 10000. While
the data collection system 10000 in one embodiment is described as
having the elements 100, 200, 300, 400, 500, the data collection
system 10000 can be implemented in such manner as to have less than
all of the noted elements, e.g., only one of the noted
elements.
[0015] In another aspect, the decodable indicia reading system 100
can include two or more imaging assemblies. In one embodiment, the
system 100 can include first and second imaging assemblies 1630 and
1730. In a further aspect, the imaging assembly 1630 can be
provided by a monochrome imaging assembly and the imaging assembly
1730 can be provided by a color imaging assembly. A skilled artisan
would appreciate the fact that decodable indicia reading systems
comprising three or more imaging assemblies are within the spirit
and the scope of the invention.
[0016] In a further aspect, the imaging assembly 1630 can include
an image sensor pixel array 1612, a monochrome image sensor 1610
and an imaging lens assembly 1620 for focusing light onto image
sensor pixel array 1612. Imaging assembly 1630 can have an imaging
axis 16. The image sensor 1610 can include a monochrome image
sensor pixel array 1612 having a plurality of monochrome pixels
disposed in a 2D array comprising a plurality of rows and columns
In a further aspect, the image sensor pixel array 1612 can be
devoid of color filters so that pixels of array 1612 are sensitive
to light in substantially all wavelengths in the visible
spectrum.
[0017] In a further aspect, the image sensor 1610 can be provided
in an image sensor integrated circuit having output processing
circuitry for amplifying and digitizing image signals output by
image sensor pixel array 1612. For capture of a frame of image
data, image signals representing light incident on pixels of array
1612 can be read out of image sensor pixel array 1612, digitized
and stored into system volatile memory 1080. Prior to performing
the read out operation, pixels of array 1612 can be exposed during
an exposure period. Signals for control of image sensor 1610, e.g.,
readout and exposure signals can be input by interface 1608 which
can be communicatively coupled to system bus 1500 for providing
communication with CPU 1060. In one embodiment, the interface 1608
can be provided by a Media Control Processor (MCP) interface.
[0018] Imaging terminal 100 can be operative so that terminal 100
captures a frame of image data responsively to trigger 1110 being
actuated. A frame captured into memory 1080 prior to further
processing by CPU 1060 can be regarded as a raw frame of image
data.
[0019] In a further aspect, the imaging assembly 1730 can include
an image sensor pixel array 1712, a color image sensor 1710 and an
imaging lens assembly 1720 for focusing light axis. Imaging
assembly 1730 can have an imaging axis 17. Image sensor 1710 can
have color image sensor pixel array 1712 having a plurality of
color pixels disposed in a 2D array having a plurality of rows and
columns In one embodiment, terminal 100 can be configured with
suitable optics so that imaging axis 16 can be coincident with
imaging axis 17. However, in another embodiment, terminal 100 can
be configured so that imaging axis 16 and imaging axis 17 are
spaced apart from one another. Terminal 100 can be configured so
that axes 16 and 17 can extend in directions that are parallel to
one another as shown in FIG. 2. In another embodiment, terminal 100
can be configured so that axes 16 and 17 extend in directions that
are non-parallel with respect to one another. In one specific
embodiment, terminal 100 can be configured so that imaging axis 16
extends forwardly from terminal 100 and imaging axis extends
downwardly from terminal 100. Imaging axis directions herein are
given as directions from an image sensor array toward a target
being subject to image capture. In one embodiment, terminal 100 can
be configured so that imaging assembly 1630 and imaging assembly
1730 define respective fields of view that at least partially
overlap.
[0020] In another aspect, the image sensor 1710 can be provided in
an image sensor integrated circuit having output processing
circuitry for amplifying and digitizing image signals output by
image sensor pixel array 1712. For capture of a frame of image
data, image signals representing light incident on pixels of array
1712 can be read out of image sensor pixel array 1712, digitized
and stored into system volatile memory 1080. Prior to performing
the read out operation, pixels of array 1712 can be exposed during
an exposure period. Signals for control of image sensor 1710, e.g.,
readout and exposure signals can be input by interface 1708 which
can be communicatively coupled to system bus 1500 for providing
communication with CPU 1060. In one embodiment, the interface 1708
can be provided by a Media Control Processor (MCP) interface.
[0021] In one embodiment as set forth herein imaging assembly 1630
can be a monochrome imaging assembly having a monochrome image
sensor 1610, and imaging assembly 1730 can be a color imaging
assembly having a color image sensor 1710.
[0022] In another embodiment as set forth herein, image sensor 1610
can be provided by a hybrid monochrome and color image sensor 1620
and imaging assembly 1630 can be a hybrid monochrome and color
imaging assembly 1630 having a hybrid monochrome and color image
sensor 1620 while imaging assembly 1730 is a color imaging assembly
having a color image sensor 1710 as set forth previously
herein.
[0023] Where imaging assembly 1630 is provided by a hybrid
monochrome and color imaging assembly, image sensor 1610 can be
provided in an image sensor integrated circuit having output
processing circuitry for amplifying and digitizing image signals
output by image sensor pixel array 1612. Image sensor pixel array
1612 can be a hybrid monochrome and color image sensor array having
a first subset of monochrome pixels without color filter elements
and a second subset of color pixels having color sensitive filter
elements. For capture of a frame of image data, image signals
representing light incident on pixels of array 1612 can be read out
of image sensor pixel array 1612, digitized and stored into system
volatile memory 1080. Prior to performing the read out operation,
pixels of array 1612 can be exposed during an exposure period.
Signals for control of image sensor 1610, e.g., readout and
exposure signals can be input by interface 1608 which can be
communicatively coupled to system bus 1500 for providing
communication with CPU 1060. In one embodiment, the interface 1608
can be provided by a Media Control Processor (MCP) interface.
[0024] In one embodiment, terminal 100 can comprise more than two
imaging assemblies, e.g., can comprise a first imaging assembly
having a hybrid monochrome and color image sensor, a second imaging
assembly having a color image sensor devoid of monochrome pixels
and a third imaging assembly having a monochrome image sensor
devoid of pixels having color filter elements, and an Nth imaging
assembly being configured similarly or differently from one of the
first, second, or third imaging assemblies.
[0025] Image terminal 100 can be operative so that terminal 100
captures a frame of image data responsively to trigger 1110 being
actuated. A frame captured into memory 1080 prior to further
processing by CPU 1060 can be regarded a raw frame.
[0026] In another aspect, for attempting to decode a bar code
symbol, e.g., a one dimensional bar code symbol, the decodable
indicia reading system 100 can process image data of a frame
corresponding to a line of pixel positions (e.g., a row, a column,
or a diagonal set of pixel positions) to determine a spatial
pattern of dark and light cells and can convert each light and dark
cell pattern determined into a character or character string via
table lookup. Where a decodable indicia representation is a 2D bar
code symbology, a decode attempt can comprise the steps of locating
a finder pattern using a feature detection algorithm, locating
matrix lines intersecting the finder pattern according to a
predetermined relationship with the finder pattern, determining a
pattern of dark and light cells along the matrix lines, and
converting each light pattern into a character or character string
via table lookup. In one embodiment, the decodable indicia reading
system 100 can be operative to capture a frame of image data and
process the frame for attempting to decode the frame responsively
to an actuation of trigger 1110. When processing a color frame of
image data for attempting to decode a decodable indicia, the system
100 can first transform the color image data into monochrome image
data. Such transformation can comprise utilizing image data from
only a single channel of pixel positions (e.g., by interpolating
pixel values for blue and red pixel positions utilizing pixel
values at green pixel positions so that an all green frame is
output, which can be regarded as a monochrome frame of image
data).
[0027] In one embodiment, the decodable indicia reading system 100
can, responsively to an actuation of the trigger 1110, capture a
frame of image data and subjects image data of a frame to a decode
attempt. Also, responsively to an actuation of the trigger 1110,
the decodable indicia reading system 100 can format image data of a
captured frame into a standard image format, e.g., BMP, PDF, JPG,
TIF and can transmit the formatted image file to an external
computer, e.g., server 200, server 400, client computer 500.
[0028] One embodiment of a physical form factor of the decodable
indicia reading system is shown in FIG. 1. Components described
with reference to FIG. 1 can be disposed within portable hand held
housing 110 and can be supported within a portable hand held
housing 110. Referring to further aspect of the data collection
system 10000, each of server 200, server 400, and client computer
500 can include components described with reference to the
decodable indicia reading system 100. In some instances, the
decodable indicia reading system 100, server 400 and client
computer 500 can have devices in addition to those shown in FIG. 1.
In some instances the servers 200, 400 and client computer 500 can
have components deleted relative to those shown in FIG. 1 (for
example, the server 200 can be devoid of a display 1140 and imaging
assemblies 1630, 1730).
[0029] As noted herein supra, the decodable indicia reading system
100 can include two or more imaging assemblies. In one embodiment,
a first imaging assembly can be provided by a monochrome imaging
assembly and a second imaging assembly can be provided by a color
imaging assembly. The inventors found that using the monochrome
image sensor for decodable reading in some situations (e.g., low
ambient light) would produce a better signal to noise ratio.
However, in other situations (e.g., for particular color spectral
contents of the image) a better signal to noise ratio (and, hence,
better decode success rate) can be obtained using a color image
sensor.
[0030] In another embodiment, a first imaging assembly can be
provided by an imaging assembly with a lower resolution than that
of a second imaging assembly. The inventors found that using the
lower resolution image sensor can be advantageous in some
situations, since the image processing time and the amount of
memory required for the processing grows exponentially with the
image resolution. Hence, the lower resolution image sensor can be
preferred in time-critical or memory-critical applications.
[0031] The selection of an image sensor which is more suitable for
the attempted decodable indicia reading operation can be based upon
comparing a measured parameter value to a pre-defined value.
[0032] In one embodiment, the sensor selection parameter can be
provided by a decoding time required to locate and decode the
decodable indicia using the captured image. As noted herein supra,
for some time-critical applications, the decoding time can be a
threshold factor in deciding whether an image obtained by a
selected image sensor is acceptable for further processing.
[0033] In another embodiment, the sensor selection parameter can be
provided by a required exposure time. High exposure values can be
unacceptable for portable form factors of the decodable indicia
reading system 100, and hence, the image sensor selection can be
based upon comparing the required exposure time to a pre-defined
threshold value.
[0034] In another embodiment, the sensor selection parameter can be
provided by the ambient light intensity. The sensor selection can
be performed by comparing the ambient light intensity to a
pre-defined value, since for a given image sensor the exposure time
dependence upon the ambient light intensity can be a known
function.
[0035] In another embodiment, the sensor selection parameter can be
provided by a signal to noise ratio obtained in the decodable
indicia image. The sensor selection can be performed by comparing
the signal-to-noise ratio to a pre-defined value.
[0036] In another aspect, measuring the sensor selection parameter
value can be performed as part of an attempted decodable indicia
locating and decoding operation. Should the attempted locating and
decoding operation fail, the image sensor selection method can be
performed as described herein supra.
[0037] In another embodiment, measuring the sensor selection
parameter value can be performed without obtaining the decodable
indicia image.
[0038] One embodiment of the method for adaptively selecting an
image sensor for reading decodable indicia by a decodable indicia
reading system according to the invention is now being described
with references to FIG. 3.
[0039] At step 310, the counter J of available image sensors can be
initialized with the value of 1. In one embodiment, at least one
image sensor can be provided by a monochrome image sensor, and at
least one image sensor can be provided by a color image sensor. In
another embodiment, at least two of available image sensors can
provide different image resolutions. In a yet another embodiment,
at least two of available image sensors can provide different
signal to noise ratios.
[0040] At step 320, a value of a sensor selection parameter can be
measured using a J-th image sensor. As noted herein supra, the
sensor selection parameter can be provided by a decoding time, a
required exposure time, an ambient light intensity, and/or a signal
to noise ratio. A skilled artisan would appreciate the fact that
measuring values of two or more sensor selection parameters is
within the spirit and the scope of the invention.
[0041] In one embodiment, measuring the sensor selection parameter
value can be performed as part of an attempted decodable indicia
locating and decoding operation. In another embodiment, different
sensor selection parameters can be used for different image
sensors.
[0042] At step 330, the measured parameter value can be compared to
a pre-defined sensor-specific threshold value for the J-th sensor.
If the measured parameter value is greater than or equal to the
pre-defined threshold value, the method can branch to step 380;
otherwise, the method can continue to step 340.
[0043] At step 340, the counter J of available image sensors can be
incremented by 1.
[0044] At step 350, the counter J can be compared to the number of
available image sensors. If the value of J is less than or equal to
the number of available image sensors, the method can cycle to step
320. Otherwise, the method can continue to step 370.
[0045] At step 370, a message to the decodable indicia reading
system operator can be displayed notifying the operator that a
suitable image sensor could not be found. The notification can also
be performed by an audible signal or a tactile signal. The method
can terminate at step 399.
[0046] At step 380, a message to the decodable indicia reading
system operator can be displayed notifying the operator that a
suitable image sensor has been selected. The notification can also
be performed by an audible signal or a tactile signal.
[0047] A skilled artisan would appreciate the fact that the
operator notification steps 370 and 380 are not essential and can
be omitted from the method implementation.
[0048] At step 390, a decodable indicia image can be obtained by
the J-th image sensor. The image can be further processed to locate
and decode the decodable indicia.
[0049] The method can terminate at step 399.
[0050] A small sample of systems methods and apparatus that are
described herein is as follows: [0051] A1. A decodable indicia
reading system comprising:
[0052] a central processing unit (CPU);
[0053] a memory communicatively coupled to said CPU;
[0054] two or more image sensors communicatively coupled to one of:
said memory, said CPU;
[0055] a hand held housing in which the two or more image sensors
are disposed; wherein said system is configured to select a
suitable image sensor for an indicia reading operation by cycling
through said two or more image sensors and comparing a measured
value of a parameter to a pre-defined sensor-specific threshold
value for each of said two or more image sensors;
[0056] wherein said system is further configured to notify an
operator of said system about selecting said suitable image sensor;
and
[0057] wherein said system is further configured to obtain a
decodable indicia image by said suitable image sensor. [0058] A2.
The system of A1, wherein said suitable image sensor is the best
suitable image sensor for said indicia reading operation. [0059]
A3. The system of A1, wherein said parameter is provided by one of:
a decoding time, a required exposure time, an ambient light
intensity, and a signal to noise ratio. [0060] A4. The system of
A1, wherein at least one image sensor of said two or more image
sensors is provided by a color image sensor. [0061] A5. The system
of A1, wherein at least one image sensor of said two or more image
sensors is provided by a monochrome image sensor. [0062] A6. The
method of A1, wherein at least one image sensor of said two or more
image sensors is provided by a hybrid monochrome and color image
sensor. [0063] A7. The system of A1, wherein said first image
sensor of said two or more image sensors is configured to provide a
first image resolution, and said second image sensor of said two or
more image sensors is configured to provide a second image
resolution; and
[0064] wherein said second image resolution is greater than said
first image resolution. [0065] A8. The system of A1, wherein said
first image sensor of the two or more image sensors is configured
to provide a first signal to noise ratio, and said second image
sensor of the two or more image sensors is configured to provide a
second signal to noise ratio; and
[0066] wherein said second signal to noise ratio is greater than
said first signal to noise ratio. [0067] A9. The system of A1
further configured to notify said operator by at least one of: an
audible signal, a visual signal, a tactile signal. [0068] B1. A
method for adaptively selecting an image sensor for reading
decodable indicia by a decodable indicia reading system including
two or more image sensors that are disposed within a hand held
housing, said method comprising the steps of:
[0069] (i) for each image sensor of said two or more image sensors
determining whether said image sensor is suitable for an attempted
indicia reading operation by comparing a measured value of a
parameter to an image sensor-specific pre-defined value;
[0070] (ii) performing at least one of: (a) conditionally branching
to step (iii) upon detecting a second image sensor for which said
step of comparing yields a pre-defined result, and (b) selecting a
second image sensor for which said step of comparing yields the
best result among all image sensors of said two or more image
sensors;
[0071] (iii) obtaining a decodable indicia image by said second
image sensor. [0072] B2. The method of B1, wherein said step (iii)
is preceded by a step of notifying an operator of said decodable
indicia reading system about said second image sensor having been
selected for an attempted indicia reading operation [0073] B3. The
method of B1, wherein said parameter is provided by one of: a
decoding time, a required exposure time, an ambient light
intensity, and a signal to noise ratio. [0074] B4. The method of
B1, wherein at least one image sensor of said two or more image
sensors is provided by a color image sensor. [0075] B5. The method
of B1, wherein at least one image sensor of said two or more image
sensors is provided by a monochrome image sensor. [0076] B6. The
method of B1, wherein at least one image sensor of said two or more
image sensors is provided by a hybrid monochrome and color image
sensor. [0077] B7. The method of B1, wherein said first image
sensor of said two or more image sensors is configured to provide a
first image resolution, and said second image sensor of said two or
more image sensors is configured to provide a second image
resolution; and
[0078] wherein said second image resolution is greater than said
first image resolution. [0079] B8. The method of B 1, wherein said
first image sensor of the two or more image sensors is configured
to provide a first signal to noise ratio, and said second image
sensor of the two or more image sensors is configured to provide a
second signal to noise ratio; and
[0080] wherein said second signal to noise ratio is greater than
said first signal to noise ratio. [0081] B9. The method of B2,
wherein said step of notifying is performed by at least one of: an
audible signal, a visual signal, a tactile signal. [0082] C1. A
method for adaptively selecting an image sensor for reading
decodable indicia by a decodable indicia reading system including
two or more image sensors, said method comprising the steps of:
[0083] (i) obtaining a decodable indicia image by a first image
sensor;
[0084] (ii) attempting to locate and decode a decodable indicia
within said decodable indicia image;
[0085] (iii) conditionally, upon said step (ii) failure, performing
the following steps (iv)-(vii):
[0086] (iv) measuring a value of a parameter for said decodable
indicia image;
[0087] (v) for each image sensor of said two or more image sensors
excluding said first image sensor, determining whether said image
sensor is suitable for an attempted indicia reading operation by
comparing said value to an image sensor-specific pre-defined
value;
[0088] (vi) performing at least one of: (a) conditionally branching
to step (vii) upon detecting a second image sensor for which said
step of comparing yields a pre-defined result, and (b) selecting a
second image sensor for which said step of comparing yields the
best result among all image sensors of said two or more image
sensors;
[0089] (vii) obtaining a decodable indicia image by said second
image sensor. [0090] C2. The method of C1, wherein said step (iv)
is preceded by a step of notifying an operator of said decodable
indicia reading system about said second image sensor having been
selected for an attempted indicia reading operation [0091] C3. The
method of C1, wherein said parameter is provided by one of: a
decoding time, a required exposure time, an ambient light
intensity, and a signal to noise ratio. [0092] C4. The method of
C1, wherein at least one image sensor of said two or more image
sensors is provided by a color image sensor. [0093] C5. The method
of C1, wherein at least one image sensor of said two or more image
sensors is provided by a monochrome image sensor. [0094] C6. The
method of C1, wherein at least one image sensor of said two or more
image sensors is provided by a hybrid monochrome and color image
sensor. [0095] C7. The method of C1, wherein said first image
sensor of said two or more image sensors is configured to provide a
first image resolution, and said second image sensor of said two or
more image sensors is configured to provide a second image
resolution; and
[0096] wherein said second image resolution is greater than said
first image resolution. [0097] C8. The method of C1, wherein said
first image sensor of the two or more image sensors is configured
to provide a first signal to noise ratio, and said second image
sensor of the two or more image sensors is configured to provide a
second signal to noise ratio; and
[0098] wherein said second signal to noise ratio is greater than
said first signal to noise ratio. [0099] C9. The method of C2,
wherein said step of notifying is performed by at least one of: an
audible signal, a visual signal, a tactile signal.
[0100] While the present invention has been described with
reference to a number of specific embodiments, it will be
understood that the true spirit and scope of the invention should
be determined only with respect to claims that can be supported by
the present specification. Further, while in numerous cases herein
wherein systems and apparatuses and methods are described as having
a certain number of elements it will be understood that such
systems, apparatuses and methods can be practiced with fewer than
or greater than the mentioned certain number of elements. Also,
while a number of particular embodiments have been described, it
will be understood that features and aspects that have been
described with reference to each particular embodiment can be used
with each remaining particularly described embodiment.
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