CN115406531A - Method and system for evaluating color characterization capability of multispectral sensor - Google Patents
Method and system for evaluating color characterization capability of multispectral sensor Download PDFInfo
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Abstract
The application relates to the technical field of sensors, in particular to a method and a device for evaluating color characterization capability of a multispectral sensor. The evaluation method comprises the following steps: acquiring a quantum efficiency curve graph of the multispectral sensor to be detected; the quantum efficiency curve graph comprises a plurality of quantum efficiency curves, and each quantum efficiency curve corresponds to a channel of the multispectral sensor to be tested; calculating the tristimulus values corresponding to all channels according to the quantum efficiency curve; calculating corresponding color coordinates of each channel in a chromaticity coordinate system according to the tristimulus values; and evaluating the color characterization capability of the multispectral sensor according to the color coordinates. The method and the device are simple to operate, easy to implement and clear in analysis result.
Description
Technical Field
The application relates to the technical field of sensors, in particular to a method and a device for evaluating color characterization capability of a multispectral sensor.
Background
Evaluation indexes of a conventional digital image sensor include uniformity, distortion and the like of image dimensions, but do not include evaluation of color resolution capability. When the digital image sensor images more abundant colors, some sensors can express more colors, and some sensors can express less colors. At present, a method for evaluating the quantity of colors which can be expressed by a digital image sensor from a hardware index is lacked.
The same problem is faced with multispectral sensors. The filtering performance of the multispectral sensor varies, and the color expression capability of different multispectral sensors is at the same level, so that no better quantitative index and method exist.
Disclosure of Invention
In view of this, embodiments of the present application provide a method and an apparatus for evaluating color characterization capability of a multispectral sensor, which can solve at least one technical problem in the related art.
In a first aspect, an embodiment of the present application provides a method for evaluating color characterization capability of a multispectral sensor, including: obtaining a quantum efficiency curve graph of the multispectral sensor to be measured; the quantum efficiency curve graph comprises a plurality of quantum efficiency curves, and each quantum efficiency curve corresponds to a channel of the multispectral sensor to be tested; calculating the tristimulus values corresponding to all the channels according to the quantum efficiency curve; calculating corresponding color coordinates of each channel in a chromaticity coordinate system according to the tristimulus values; evaluating a color characterization capability of the multispectral sensor according to the color coordinates.
According to the method for evaluating the color representation capability of the multispectral sensor, the color expression capability of the multispectral sensor is evaluated by calculating the quantum efficiency curve of the multispectral sensor, the operation is simple, the implementation is easy, and the analysis result is clear.
In some embodiments, the calculating the corresponding color coordinate of each channel in the chromaticity coordinate system according to the tristimulus value includes: and calculating chromatic values according to the tristimulus values, and marking the chromatic values corresponding to the channels in a chromatic coordinate system to obtain the chromatic coordinates corresponding to the channels.
In some embodiments, said evaluating color characterization capabilities of said multispectral sensor according to said color coordinates comprises: determining a first closed area which has the largest area and can be enclosed by the color coordinates corresponding to all the channels; and determining the area ratio of the first closed area to a second closed area enclosed by a standard chromaticity diagram, and determining the color characterization capability of the multispectral sensor according to the area ratio.
In some embodiments, the color characterization capability of the multispectral sensor is proportional to the area fraction.
In some embodiments, the determining a maximum enclosed area that can be enclosed by the color coordinates corresponding to each of all the channels includes: expressing the color coordinates corresponding to all the channels in a standard chromaticity diagram to obtain a plurality of coordinate points; and connecting at least part of the plurality of coordinate points to obtain a first closed area with the largest area.
In some embodiments, said evaluating color characterization capabilities of said multispectral sensor from said color coordinates comprises: determining a first closed area which has the largest area and can be enclosed by the color coordinates corresponding to all the channels; and acquiring the color characterization capability of the multispectral sensor according to the area size of the first closed region.
In some embodiments, the color characterization capability is proportional to the area size.
In a second aspect, an embodiment of the present application provides a system for evaluating color characterization capabilities of a multispectral sensor, comprising a monochromator, an optical power meter, a processor, a memory, and a computer program stored in the memory and executable on the processor; the monochromator is used for providing narrow-band optical signals for the multispectral sensor to be detected; the optical power meter is used for measuring the optical power value of the optical signal; the processor is configured to acquire an exposure time and an output signal of the multispectral sensor to be measured under the optical signal, calculate quantum efficiency according to the exposure time, the output signal, and an optical power value of the optical signal, obtain a quantum efficiency curve of the multispectral sensor to be measured, and implement the method for evaluating the color characterization capability of the multispectral sensor according to any embodiment of the first aspect when executing a computer program.
In a third aspect, an embodiment of the present application provides an electronic device, including: a memory, a processor and a computer program stored in the memory and executable on the processor, the processor when executing the computer program implementing the method for multispectral sensor color characterization capability assessment as described in any embodiment of the first aspect.
In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the computer program implements the method for evaluating the color characterization capability of a multispectral sensor according to any embodiment of the first aspect.
In a fifth aspect, an embodiment of the present application provides a computer program product, which when run on an electronic device, causes the electronic device to perform the method for evaluating multispectral sensor color characterization capability according to any embodiment of the first aspect.
It should be understood that the beneficial effects of the second aspect to the fifth aspect can be referred to the related description of the embodiment of the first aspect, and are not described herein again.
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In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.
Fig. 1 is a schematic structural diagram of an evaluation system for color characterization capability of a multispectral sensor according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a quantum efficiency curve for an 8-channel multispectral sensor according to an embodiment of the present application;
FIG. 3 is a schematic diagram of a quantum efficiency curve for a 3-channel multispectral sensor provided by an embodiment of the present application;
FIG. 4 is a schematic flow chart of an implementation of a method for evaluating color characterization capability of a multispectral sensor according to an embodiment of the present application;
fig. 5 is a schematic flow chart illustrating the implementation of step S440 in the method for evaluating color characterization capability of a multispectral sensor according to an embodiment of the present application;
FIG. 6 is a schematic diagram of color coordinates of an 8-channel multispectral sensor provided in an embodiment of the present application;
FIG. 7 is a schematic diagram of color coordinates of a 3-channel multispectral sensor provided by an embodiment of the present application;
FIG. 8 is a schematic structural diagram of an apparatus for evaluating color characterization capability of a multispectral sensor according to an embodiment of the present application;
FIG. 9 is a schematic structural diagram of an evaluation module in an evaluation apparatus for multi-spectral sensor color characterization capability according to an embodiment of the present application;
fig. 10 is a schematic structural diagram of an evaluation module in an evaluation apparatus for multispectral sensor color characterization capability according to another embodiment of the present application.
Detailed Description
In the following description, for purposes of explanation and not limitation, specific details are set forth such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.
The term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.
Reference throughout this specification to "one embodiment," "some embodiments," or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.
Further, in the description of the present application, "a plurality" means two or more. The terms "first" and "second," etc. are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.
In order to explain the technical solution described in the present application, the following description will be given by way of specific examples.
The multispectral sensor is a digital image sensor using multispectral imaging technology, and comprises a plurality of detectors corresponding to different wave bands and used for collecting spectral information of the different wave bands to obtain multispectral images. In general, single-band imaging is performed by placing an object to be detected under a single-band detection light (substantially an electromagnetic wave) to collect radiance, and obtain a spectral image. The multispectral imaging used by the multispectral sensor is to place a target to be detected under detection light of different wave bands to collect radiance to obtain a multispectral image. The digital image sensor essentially converts a certain number of photons incident on the image element surface within the exposure time into a certain number of electrons, and then converts the electrons into a voltage signal with a certain amplitude through a capacitor for storing the charges, and the signal is amplified and quantized to finally become the gray value of the digital image. The photoelectric performance of the digital image sensor needs to be tested in the manufacturing and factory-leaving process, and the evaluation of the color characterization capability of the multispectral sensor also belongs to the test of the photoelectric performance.
Evaluation of the multispectral sensor color characterization capability is used to detect whether the color gamut of the manufactured multispectral sensor meets expected requirements. On the premise that the number of channels of the multispectral sensor is fixed, the color gamut is a main evaluation index of the multispectral sensor quality, the color gamut refers to a range area formed by the number of colors which can be expressed by a certain color expression mode, and also refers to a color range which can be expressed by specific media such as screen display, digital output and printing replication. On the production line, after evaluating the color characterization capability of the multispectral sensor on the sampled and manufactured product, if the color gamut does not meet the expected requirement, the corresponding adjustment needs to be made on the production process, so that the performance of the multispectral sensor in subsequent batch production can meet the expected performance.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a system for evaluating color characterization capability of a multispectral sensor according to an embodiment of the present invention. In this embodiment, the system for evaluating the color characterization capability of the multispectral sensor comprises a processor 110, a memory 111, a computer program 112 stored in the memory 111 and operable on the processor 110, a monochromator 120, and an optical power meter 121.
Monochromator 120 is a spectroscopic instrument suitable for the production of monochromatic light. The monochromator can output a series of independent optical signals with a sufficiently narrow spectral interval, and the wavelength of the output optical signals can be continuously adjusted according to needs. In this embodiment, the monochromator 120 is used to provide a narrow band of optical signals to the multispectral sensor under test. Optical power meter 121 refers to an instrument for measuring absolute optical power or relative loss of optical power through a length of optical fiber. In the present embodiment, the optical power meter 121 is used to measure the optical power value of the optical signal output by the monochromator 120. The processor 110, the memory 111, and the computer program 112 stored in the memory 111 and operable on the processor 110 may be integrated on an electronic device, which is not limited herein.
In this embodiment, the system for evaluating the color characterization capability of the multispectral sensor can be used for evaluating the color characterization capability of the multispectral sensor. To better illustrate how the evaluation system performs the evaluation of the color characterization capability of the multispectral sensor, the following briefly describes the test principle:
the multispectral sensor color characterization capability is related to the quantum efficiency corresponding to each channel of the multispectral sensor, and the quantum efficiency is defined as the ratio of the number of photoelectrons generated by the absorption of incident photons by the multispectral sensor to the number of incident photons, which reflects the spectral sensitivity of the imaging device in the spectral response range.
When measuring quantum efficiency, firstly, an optical power meter is used for measuring the energy of a monochromatic uniform light source under certain light intensity and testing the output signal of a device under the monochromatic light. Calculating the light energy E received by a single pixel within a certain integration time under a specific wavelength according to the formula (1) λ 。
Wherein P is the output power of the optical power meter, A d The area of the pixel of the sensor to be measured, T is the integration time of the sensor, A s The probe area of the optical power meter.
The energy of a single photon at a specific wavelength λ is calculated using equation (2).
Where h is the constant of the brownian point and c is the speed at which light propagates in a vacuum.
Calculating the number of photons N received by each pixel during the integration time according to formula (3) λ 。
Wherein E is λ Representing the light energy received by each picture element during a certain integration time, E γ Representing the energy of a single photon.
Then calculate each image according to the formula (4)Number of electrons N generated and collected e 。+
Wherein, V 0 Representing the sensor output signal (Dn), S V Representing the conversion gain (DN/e-) of the sensor.
The quantum efficiency η is calculated according to the formula (5) according to the definition of the quantum efficiency. +
Wherein N is e Representing the number of electrons, N, of each picture element λ Representing the number of photons received by each picture element during the integration time.
The quantum efficiency testing step comprises the following steps: firstly, calibrating the optical power of different wavelengths, placing an optical power meter probe at the front position A of a dry monochromatic uniform light source to ensure that the monochromatic light source can be uniformly irradiated on the optical power meter probe, scanning a monochromator at a fixed step pitch within a wavelength measuring range, and recording the optical power value P under each wavelength; taking off the optical power meter, placing the sensor to be measured at the same position A, ensuring that a monochromatic light source can uniformly irradiate the surface of the sensor to be measured, scanning a monochromator at a fixed step pitch within a measurement wavelength range, adjusting the exposure time of the sensor under each wavelength to enable the output value of the sensor to reach half saturation, and recording the exposure time T and the output mean value (DN) of the sensor under each wavelength; in order to collect materials conveniently, the exposure time of the image sensor can be fixed, but the output of the sensor cannot be overexposed. Wherein, the exposure time refers to the exposure time of the sensor, the output average value refers to the signal value of the sensor and is expressed by a digital quantity (DN); because the number of photoelectrons (e-) collected by the sensor within a certain exposure time is required to be obtained and the number of electrons is difficult to measure, the number of electrons (e-) is indirectly calculated by adopting the ratio of the output signal value (DN) to the conversion gain (DN/e-); the conversion gain (unit can be DN/e-, or uV/e-) can be understood as the conversion coefficient of the signal conversion stage (charge > voltage > digital signal) collected by the image sensor.
In this embodiment, the processor 110 obtains the quantum efficiency of each channel of the multispectral sensor based on the above test steps, and further obtains a quantum efficiency curve of the sensor. The quantum efficiency curve graph of the multispectral sensor comprises a plurality of quantum efficiency curves, and each quantum efficiency curve corresponds to one channel of the multispectral sensor. Taking a multispectral sensor with 8 channels as an example, as shown in fig. 2, a quantum efficiency curve graph of 8 channels of the multispectral sensor can be measured, where each of the 8 quantum efficiency curves corresponds to one channel; with the multispectral sensor as 3 channels, as shown in fig. 3, a quantum efficiency curve graph of 3 channels of the multispectral sensor can be measured, where each of the 3 quantum efficiency curves corresponds to one channel.
The embodiment of the application provides an evaluation method for the color characterization capability of a multispectral sensor, which can be used for obtaining a quantum efficiency curve graph of the multispectral sensor by utilizing the system test provided by the embodiment to further evaluate the color expression capability range of the multispectral sensor, and has the advantages of simple operation, easy implementation and clear analysis result.
Fig. 4 is a schematic flow chart of an implementation of a method for evaluating color characterization capability of a multispectral sensor according to an embodiment of the present application, where the method for evaluating color characterization capability of a multispectral sensor according to the present application is executable by an electronic device. As shown in fig. 4, the evaluation method may include steps S410 to S440.
S410, obtaining a quantum efficiency curve graph of the multispectral sensor to be measured.
The quantum efficiency curve graph comprises a plurality of quantum efficiency curves, and each quantum efficiency curve corresponds to a channel of the multispectral sensor to be detected. The number of channels of the multispectral sensor is not limited in the embodiments of the present application, and is, for example, 4 channels, 8 channels, 9 channels, and the like.
And S420, calculating the tristimulus values corresponding to the channels according to the quantum efficiency curve.
After the quantum efficiency curves of all the channels are obtained, the electronic equipment calculates the tristimulus values corresponding to all the channels according to the quantum efficiency curves of all the channels. The tristimulus values include X (red primary stimulus amount), Y (green primary stimulus amount), and Z (blue primary stimulus amount).
The embodiment of the present application does not specifically limit the method for calculating the tristimulus values according to the quantum efficiency curve, and all methods that can be used for achieving the purpose of the present invention can be used for the present application.
In one embodiment, the quantum efficiency curve of the first channel is: c1= C _1 (1,m), wavelength = w (1,m), where m denotes the number of wavelengths. Calculating X, Y and Z tristimulus values of the first channel according to the quantum efficiency curve:
C1_X＝X.*C1
＝s_x(1)*c_1(1)+s_x(2)*c_1(2)+......+s_x(m)*c_1(m)
C1_Y＝Y.mC1
＝s_y(1)mc_1(1)+s_y(2)mc_1(2)+......+s_y(m)mc_1(m)
C1_Z＝Z.*C1
＝s_z(1)*c_1(1)+s_z(2)mc_1(2)+......+s_z(m)mc_1(m)
wherein, C1_ X, C _ Y and C1_ Z sequentially represent X, Y and Z tristimulus values of the first channel, X, Y, Z represent XYZ parameter values of CIE1931XYZ, respectively, C1 represents a quantum efficiency curve of the first channel, s _ X is a matrix representation of tristimulus values X, s _ Y is a matrix representation of tristimulus values Y, and s _ Z is a matrix representation of tristimulus values Z. In the same way, the tristimulus values of the other channels can be calculated.
And S430, calculating corresponding color coordinates of each channel in a chromaticity coordinate system according to the tristimulus values.
The embodiment of the present application is not particularly limited to the method for calculating color coordinates from tristimulus values, and all methods that can be used for achieving the object of the present invention can be used for the present application.
In one embodiment, the chromaticity values are calculated according to the tristimulus values, and the chromaticity values corresponding to the channels are marked in a chromaticity coordinate system to obtain the color coordinates corresponding to the channels.
Specifically, for a first channel, the chroma value of the first channel is calculated according to X, Y and the Z tristimulus value of the first channel:
wherein, C1_ X, C _ Y and C1_ Z sequentially represent X, Y and Z tristimulus values of the first channel. It should be noted that, since C1_ x + C1_ y + C1_ z =1, the chroma value of the first channel can be expressed only by (C1 _ x, C1_ y), and the chroma value (C1 _ x, C1_ y) corresponding to the first channel is labeled in the chroma coordinate system, so as to obtain the color coordinate corresponding to the first channel. In the same way, the color coordinates of the remaining channels can be calculated.
And S440, evaluating the color characterization capability of the multispectral sensor according to the color coordinates.
After obtaining the color coordinates corresponding to all the channels, the electronic device evaluates the color characterization capability of the multispectral sensor according to the color coordinates.
In some possible embodiments, the color characterization capability of the multispectral sensor may be evaluated based on the area of the enclosed region enclosed by the color coordinates. The larger the area of the enclosed area is, the stronger the color characterization capability of the multispectral sensor is, and the weaker the color characterization capability is. The color characterization capability is proportional to the size of the enclosed area enclosed. Preferably, in one embodiment, the color characterization capability of the multispectral sensor can be evaluated based on the closed region with the largest area surrounded by the color coordinates.
In other possible embodiments, the area of the first closed region enclosed by the color coordinates may be compared with the area of the second closed region enclosed by the standard chromaticity diagram to obtain the color characterization capability of the multispectral sensor. Specifically, the area ratio of the first closed area to the area of the second closed area is determined, and the larger the ratio is, the stronger the color characterization capability of the multispectral sensor is, and the color characterization capability is in direct proportion to the ratio. Preferably, in one embodiment, as shown in fig. 5, step S440 may include steps S441 and S442.
And S441, determining a first closed area with the largest area surrounded by the color coordinates corresponding to all the channels.
And S442, determining the area ratio of the first closed region to a second closed region defined by the standard chromaticity diagram, and determining the color characterization capability of the multispectral sensor according to the area ratio.
In one possible implementation, step S441 includes: expressing the color coordinates corresponding to all the channels in a standard chromaticity diagram to obtain a plurality of coordinate points; and connecting at least part of the coordinate points in the plurality of coordinate points to obtain a first closed area with the largest area.
As a non-limiting example, the 8 color coordinates corresponding to each of the 8 channels shown in fig. 1 are plotted in a standard chromaticity diagram, resulting in 8 circles as shown in fig. 6. To obtain the first closed region with the largest characteristic area, it can be obtained by finding the outermost circle and connecting it with a straight line to form a closed region, such as the region B shown in fig. 6. The larger the area of region B, the stronger the color characterization capability of the multispectral sensor. As an alternative to this non-limiting example, and with continued reference to fig. 6, the area a is a second closed area surrounded by the standard chromaticity diagram, and the area B is determined to have a higher proportion than the area a, the higher proportion the color characterization capability of the multispectral sensor is, and the weaker proportion the color characterization capability of the multispectral sensor is.
As another non-limiting example, 3 color coordinates corresponding to each of the 3 channels shown in fig. 3 are plotted in a standard chromaticity diagram, resulting in 3 circles as shown in fig. 7. A first closed area can be obtained by connecting the 3 circles with a straight line. The larger the area of the first closed region, the stronger the color characterization capability of the 3-channel multispectral sensor shown in fig. 3, i.e., the wider the detectable color gamut of the multispectral sensor is illustrated. As an alternative to this non-limiting example, and with continued reference to fig. 7, the area fraction of the first closed region compared to the second closed region enclosed by the standard chromaticity diagram is determined, with the greater the area fraction the greater the color characterization capability of the multispectral sensor, and the lesser the opposite.
It should be noted that comparing fig. 6 and 7 shows that 8 channels are superior to 3 channels of multispectral sensor in color characterization. That is, the wider the gamut that can be expressed by the narrow-channel quantum efficiency curve.
According to the method for evaluating the color representation capability of the multispectral sensor, the color expression capability of the multispectral sensor is evaluated by calculating the quantum efficiency curve of the multispectral sensor, the operation is simple, the implementation is easy, and the analysis result is clear.
It should be understood that, the sequence numbers of the steps in the foregoing embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.
An embodiment of the present application further provides an evaluation device for color characterization capability of a multispectral sensor. The evaluation apparatus is not described in detail in the above description of the embodiments of the evaluation method.
Referring to fig. 8, fig. 8 is a schematic structural diagram of an apparatus for evaluating a color characterization capability of a multispectral sensor according to an embodiment of the present application. The evaluation device includes: an acquisition module 71, a first calculation module 72, a second calculation module 73 and an evaluation module 74. The obtaining module 71 is configured to obtain a quantum efficiency curve of the multispectral sensor to be measured. The quantum efficiency curve graph comprises a plurality of quantum efficiency curves, and each quantum efficiency curve corresponds to a channel of the multispectral sensor to be detected. And the first calculating module 72 is configured to calculate a tristimulus value corresponding to each channel according to the quantum efficiency curve. And a second calculating module 73, configured to calculate, according to the tristimulus values, color coordinates corresponding to each channel in the chromaticity coordinate system. An evaluation module 74 for evaluating the color characterization capability of the multispectral sensor based on the color coordinates.
In some embodiments, the second calculating module 73 is specifically configured to: and calculating the chromatic value according to the tristimulus values, and marking the chromatic value corresponding to each channel in a chromatic coordinate system to obtain the color coordinate corresponding to each channel.
In some embodiments, as shown in FIG. 9, the evaluation module 74 includes: a first determination sub-module 741 and a first comparison sub-module 742. The first determining submodule 741 is configured to determine a first closed region with a largest area that can be enclosed by color coordinates corresponding to all channels. And a first comparison submodule 742 for determining an area ratio of the first closed region to a second closed region defined by the standard chromaticity diagram, and determining a color characterization capability of the multispectral sensor according to the area ratio. Wherein the color characterization capability of the multispectral sensor is proportional to the area fraction.
In some embodiments, the first determining sub-module 741 is specifically configured to: expressing the color coordinates corresponding to all the channels in a standard chromaticity diagram to obtain a plurality of coordinate points; and connecting at least part of the plurality of coordinate points to obtain a first closed region with the largest area.
In other embodiments, as shown in FIG. 10, the evaluation module 74 includes: a second determination submodule 743 and a second acquisition submodule 744. The second determining submodule 743 is configured to determine a first closed region which is the largest in area and can be enclosed by color coordinates corresponding to all channels; and the second obtaining sub-module 744 is used for obtaining the color characterization capability of the multispectral sensor according to the area size of the first closed region. Wherein the multispectral sensor color characterization capability is proportional to the area size of the first enclosed region.
In embodiments of the application, the electronic device may include one or more processors 110 (only one shown in fig. 1), a memory 111, and a computer program 112 stored in the memory 111 and operable on the one or more processors 110, for example, an evaluation program of the multispectral sensor color characterization capability. The one or more processors 110, when executing the computer program 112, may implement various steps in an embodiment of a method for evaluation of multispectral sensor color characterization capabilities. Alternatively, one or more processors 110, when executing computer program 112, may implement the functions of the various modules/units in the evaluation device embodiment of multispectral sensor color characterization capability, and is not limited herein.
Those skilled in the art will appreciate that the electronic device shown in fig. 1 is merely an example of an electronic device and does not constitute a limitation of electronic devices. The electronic device may include more or fewer components than shown, or combine certain components, or different components, e.g., the electronic device may also include input-output devices, network access devices, buses, etc.
In one embodiment, the Processor 110 may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, discrete hardware component, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
In one embodiment, the storage 111 may be an internal storage unit of the electronic device, such as a hard disk or a memory of the electronic device. The memory 111 may also be an external storage device of the electronic device, such as a plug-in hard disk, a Smart Memory Card (SMC), a Secure Digital (SD) card, a flash memory card (flash card), and the like provided on the electronic device. Further, the memory 111 may also include both an internal storage unit and an external storage device of the electronic device. The memory 111 is used for storing computer programs and other programs and data required by the electronic device. The memory 111 may also be used to temporarily store data that has been output or is to be output.
It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules, so as to perform all or part of the functions described above. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. For the specific working processes of the units and modules in the system, reference may be made to the corresponding processes in the foregoing method embodiments, which are not described herein again.
An embodiment of the present application further provides a computer-readable storage medium, in which a computer program is stored, which, when being executed by a processor, may implement the steps in the method embodiment for evaluating a color characterization capability of a multispectral sensor.
An embodiment of the present application provides a computer program product, which when run on an electronic device, enables the electronic device to implement the steps in the embodiments of the method for evaluating the color characterization capability of a multispectral sensor.
In the above embodiments, the description of each embodiment has its own emphasis, and reference may be made to the related description of other embodiments for parts that are not described or recited in any embodiment.
Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the technical solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus/electronic device and method may be implemented in other ways. For example, the above-described apparatus/electronic device embodiments are merely illustrative, and for example, a module or a unit may be divided into only one logic function, and may be implemented in other ways, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.
Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated modules/units, if implemented in the form of software functional units and sold or used as separate products, may be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the above method embodiments may be implemented by the present application, and a computer program that can be executed by a computer program to instruct related hardware can be stored in a computer readable storage medium, and when the computer program is executed by a processor, the steps of the above method embodiments can be implemented. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer readable medium may include: any entity or device capable of carrying computer program code, recording medium, U.S. disk, removable hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random Access Memory (RAM), electrical carrier wave signals, telecommunications signals, software distribution media, and the like. It should be noted that the computer readable medium may contain other components which may be suitably increased or decreased as required by legislation and patent practice in jurisdictions, for example, in some jurisdictions, in accordance with legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunications signals.
The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.
Claims (10)
1. A method for evaluating the color characterization capability of a multispectral sensor, comprising:
acquiring a quantum efficiency curve graph of the multispectral sensor to be detected; the quantum efficiency curve graph comprises a plurality of quantum efficiency curves, and each quantum efficiency curve corresponds to a channel of the multispectral sensor to be tested;
calculating the tristimulus values corresponding to all channels according to the quantum efficiency curve;
calculating corresponding color coordinates of each channel in a chromaticity coordinate system according to the tristimulus values;
evaluating a color characterization capability of the multispectral sensor according to the color coordinates.
2. The evaluation method of claim 1, wherein the calculating corresponding color coordinates of each channel in a chromaticity coordinate system according to the tristimulus values comprises:
and calculating a chromatic value according to the tristimulus values, and marking the chromatic value corresponding to each channel in a chromatic coordinate system to obtain a chromatic coordinate corresponding to each channel.
3. The method of claim 1 or 2, wherein said evaluating the color characterization capabilities of said multispectral sensor based on said color coordinates comprises:
determining a first closed area with the largest area which can be defined by the color coordinates corresponding to all the channels;
and determining the area ratio of the first closed area to a second closed area enclosed by a standard chromaticity diagram, and determining the color characterization capability of the multispectral sensor according to the area ratio.
4. The method of evaluation according to claim 3, wherein the color characterization capability of said multispectral sensor is proportional to said area fraction.
5. The method of claim 3, wherein the determining a maximum enclosed area that can be enclosed by the color coordinates corresponding to each of all of the channels comprises:
expressing the color coordinates corresponding to all the channels in a standard chromaticity diagram to obtain a plurality of coordinate points; and connecting at least part of the plurality of coordinate points to obtain a first closed area with the largest area.
6. The method of evaluating according to claim 1, wherein said evaluating a color characterization capability of said multispectral sensor based on said color coordinates comprises:
determining a first closed area which has the largest area and can be enclosed by the color coordinates corresponding to all the channels;
and acquiring the color characterization capability of the multispectral sensor according to the area size of the first closed region.
7. The evaluation method of claim 6, wherein the color characterization capability is proportional to the area size.
8. An evaluation system for multispectral sensor color characterization capability comprising a monochromator, an optical power meter, a processor, a memory, and a computer program stored in said memory and executable on said processor;
the monochromator is used for providing narrow-band optical signals for the multispectral sensor to be detected;
the optical power meter is used for measuring the optical power value of the optical signal;
the processor is configured to obtain an exposure time and an output signal of the multispectral sensor under test under the optical signal, calculate a quantum efficiency according to the exposure time, the output signal and an optical power value of the optical signal, obtain a quantum efficiency curve of the multispectral sensor under test, and implement the evaluation method according to any one of claims 1 to 7 when executing a computer program.
9. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the evaluation method according to any one of claims 1 to 7 when executing the computer program.
10. A computer storage medium, in which a computer program is stored which, when being executed by a processor, carries out the evaluation method according to one of claims 1 to 7.
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