JP2007158747A - Control method of solid-state image sensing device, solid-state image sensing device, and image processing program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress smears so as not to make images unnatural. <P>SOLUTION: It is judged by comparing the OB pixel data value Vob of an optical black part with a smear judgement threshold Vthob whether smears are present or not. When the smears are detected, the expansion region saturation voltage Vex of an expansion region 21b is set up as a saturation voltage Vsat in place of the liner region saturation voltage VL of a usual liner region 21a to carry out an image processing. The saturation voltage Vsat is expanded up to the expansion region saturation voltage Vex, so that the ratio of a smear component Vs occupying an analog output voltage signal 21 to the analog output voltage signal 21 is reduced, and the smears stop being conspicuous. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control method for a solid-state image pickup device, a solid-state image pickup device, and an image processing program.

  For example, in a solid-state image pickup device using a CCD as an image pickup device, when a very bright subject exists in the image pickup area as one of image noises, the amount of charge photoelectrically converted during vertical transfer cannot be ignored. A so-called smear is known in which a whitish streak that cuts the screen in the vertical direction with a luminance subject as the center appears.

  As a countermeasure against this smear, in Patent Document 1, a smear component is detected using an output of a vertical OB (optical black) pixel in an image sensor, and a smear component and a normal pixel signal are taken to obtain a smear. A technique for performing the removal is disclosed.

  However, in the above-described conventional method, since smear is detected based on the output (charge) of the OB pixel unit, the detection accuracy of the smear component is deteriorated due to the influence of the S / N ratio of the OB pixel unit. There is a concern that the image after smear removal becomes unnatural.

That is, for example, as shown in FIG. 10, vertical streak noise due to variation in smear component detection accuracy appears in the background of a high-luminance subject (in this case, a lit fluorescent lamp).
JP 2001-024943 A

The objective of this invention is providing the technique which can suppress a smear so that an image may not become unnatural.
Another object of the present invention is to provide a technique capable of suppressing smear while maintaining the color carrier balance as much as possible.

A first aspect of the present invention is a first step of reading image data from an image sensor,
A second step of detecting the presence or absence of smear from the image data;
A third step of setting a saturation voltage value of the imaging device to a second voltage value larger than a first voltage value when the smear is not detected when the smear is detected;
A control method for a solid-state imaging device including the above is provided.

According to a second aspect of the present invention, in the method for controlling a solid-state imaging device according to the first aspect,
In the second step, there is provided a control method of the solid-state imaging device that determines the presence or absence of the smear based on whether or not an output voltage as the image data from the optical black portion in the imaging element exceeds a predetermined threshold value. To do.

According to a third aspect of the present invention, in the method for controlling a solid-state imaging device according to the first aspect,
In the second step, the presence or absence of the smear is determined based on whether or not the output voltage as the image data from the optical black portion in the image sensor exceeds a predetermined threshold value,
In the third step, there is provided a control method for a solid-state imaging device that changes the second voltage value set as the saturation voltage in accordance with the magnitude of the output voltage output from the optical black unit.

According to a fourth aspect of the present invention, in the method for controlling a solid-state imaging device according to the first aspect,
The first voltage value is a value corresponding to the output voltage at the upper limit of a linear region in which an exposure amount with respect to the image sensor and an output voltage as the image data from the image sensor are substantially proportional.
The second voltage value provides a control method for a solid-state imaging device that is set to the output voltage in an extended region that exceeds the linear region.

According to a fifth aspect of the present invention, in the method for controlling a solid-state imaging device according to the first aspect,
Furthermore, the present invention provides a control method for a solid-state imaging device, including a fourth step of determining a luminance or saturation of a pixel corresponding to the output voltage as a ratio of the output voltage to the saturation voltage.

A sixth aspect of the present invention is a solid-state imaging device including an imaging unit that converts light into a voltage, and an image processing unit that forms an image based on the voltage,
The image processing means determines the presence or absence of smear based on whether or not the voltage output from the optical black portion in the imaging means exceeds a predetermined threshold, and the image pick-up is performed when the smear is detected. A solid-state imaging device including a function of setting a saturation voltage value of an element to a second voltage value larger than a first voltage value when the smear is not detected is provided.

According to a seventh aspect of the present invention, in the solid-state imaging device according to the sixth aspect,
The image processing means provides a solid-state imaging device that changes the second voltage value set as the saturation voltage according to the magnitude of the output voltage output from the optical black unit.

According to an eighth aspect of the present invention, in the solid-state imaging device according to the sixth aspect,
The first voltage value is a value corresponding to the output voltage at the upper limit of a linear region in which the exposure amount with respect to the imaging unit and the output voltage from the imaging device are substantially proportional,
The second voltage value provides a solid-state imaging device that is set in an extended region that exceeds the linear region.

According to a ninth aspect of the present invention, in the solid-state imaging device according to the eighth aspect,
The image processing means provides a solid-state imaging device that determines luminance or saturation of a pixel corresponding to the output voltage as a ratio of the output voltage to the saturation voltage.

According to a tenth aspect of the present invention, there is provided an image processing program for controlling a solid-state imaging device including an imaging element and a computer that processes image data output from the imaging element.
In the computer,
A first step of reading image data from the image sensor;
A second step of detecting the presence or absence of smear from the image data;
A third step of setting a saturation voltage value of the imaging device to a second voltage value larger than a first voltage value when the smear is not detected when the smear is detected;
An image processing program for executing the above is provided.

An eleventh aspect of the present invention is the image processing program according to the tenth aspect,
In the second step, there is provided an image processing program for determining the presence or absence of the smear based on whether or not an output voltage as the image data from the optical black portion in the image sensor exceeds a predetermined threshold value.

According to a twelfth aspect of the present invention, in the image processing program according to the tenth aspect,
In the second step, the presence or absence of the smear is determined based on whether or not the output voltage as the image data from the optical black portion in the image sensor exceeds a predetermined threshold value,
In the third step, an image processing program for changing the second voltage value set as the saturation voltage according to the magnitude of the output voltage output from the optical black section is provided.

According to a thirteenth aspect of the present invention, in the image processing program according to the tenth aspect,
The first voltage value is a value corresponding to the output voltage at the upper limit of a linear region in which an exposure amount to the image sensor and an output voltage as the image data from the image sensor are substantially proportional
The second voltage value provides an image processing program that is set to the output voltage in an extended region that exceeds the linear region.

According to a fourteenth aspect of the present invention, in the image processing program according to the tenth aspect,
Furthermore, an image processing program for causing the computer to execute a process of determining luminance or saturation of a pixel corresponding to the output voltage as a ratio of the output voltage to the saturation voltage is provided.

  That is, normally, when handling an output signal from an image sensor such as a CCD, the output voltage range used as image data is only a region where the exposure amount to the image sensor and the output voltage from the image sensor are linear. In the case of the present invention, when smear is detected in the image, the range of the output voltage used as the image data is expanded to a non-linear region, and apparent smear is suppressed.

  In other words, the brightness and saturation of each pixel are the maximum voltage width that can be taken by the output voltage of each pixel (conventional saturation voltage fixed at the maximum voltage value in the linear region) and the actual output voltage. Determined by the ratio.

  In the present invention, smear is suppressed by dynamically changing the voltage serving as a reference for processing such individual pixels in accordance with the presence or absence of smear to reduce the influence of the smear component on the image quality.

According to the present invention, it is possible to suppress smear so that an image does not become unnatural.
Further, it is possible to suppress smear while maintaining the color carrier balance as much as possible.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, the principle of the present invention will be briefly described, and then embodiments will be described.
FIG. 1 is a diagram for explaining the principle of the solid-state imaging device control method, solid-state imaging device, and image processing program of the present invention.

FIG. 2 is a graph illustrating the principle of the solid-state imaging device control method, solid-state imaging device, and image processing program of the present invention.
FIG. 3 is a diagram illustrating the principle of the solid-state imaging device control method, solid-state imaging device, and image processing program according to an embodiment of the present invention.

FIG. 4 is a graph for explaining the principle of the solid-state imaging device control method, solid-state imaging device, and image processing program according to an embodiment of the present invention.
The relationship between the exposure amount and the output voltage (analog output voltage signal 21 described later) in the image sensor 11 such as a CCD is linear up to a certain amount of exposure as shown in FIG. 1, but gradually becomes non-linear. (Non-linear region). Normally, only the linear region is used because the color carrier balance is lost and the normal image cannot be created if the image is composed using the non-linear region.

The threshold value of the output voltage region of the image sensor 11 used when constructing this image is called “saturation voltage”.
The smear increases as the intensity of the light applied to the image sensor 11 increases. However, when the output of the image sensor 11 does not reach the saturation voltage, the output voltage increases with the intensity of light, so the smear is not noticeable. .

However, when the image is taken in a very bright place, as shown in FIG. 2, the output voltage (total charge amount) of the image sensor 11 exceeds the saturation voltage, only the smear component increases, and the smear becomes conspicuous.
Therefore, in this embodiment, as a technique for making smear inconspicuous, when the smear component exceeds a certain amount, the saturation voltage is used up to a non-linear region.

Specifically, the following technique is adopted as an example.
First, as shown in FIG. 3, the area of the output voltage (analog output voltage signal 21 described later) of the image sensor 11 is divided into a linear area 21a, an extended area 21b, and an invalid area 21c.

When smear occurs, the saturation voltage range is expanded to the expansion region 21b according to the output voltage of the image sensor 11.
By taking such a method, it is possible to suppress the appearance smear of the created image as illustrated in FIG.

  That is, when the luminance and saturation of each pixel are calculated as the ratio of the output voltage of the pixel to the saturation voltage with the saturation voltage as a full range, the net image component VG can be obtained by setting the saturation voltage large. The amount to be cut off becomes small, the ratio of the smear component Vs to the image component VG becomes relatively small, and the smear becomes inconspicuous.

  In this case, since the image component VG exceeding the linear region 21a is also used for image creation, the carrier balance is slightly disrupted. However, since the image is relatively deteriorated in the vicinity of a high-luminance subject where smear originally occurs, this embodiment is performed. As a result, a good quality image can be obtained by using the method of the form.

Hereinafter, the control method of the solid-state imaging device, the solid-state imaging device, and the image processing program according to the present embodiment will be described in more detail.
FIG. 5 is a block diagram illustrating an example of a configuration of a solid-state imaging device that implements a control method and an image processing program for a solid-state imaging device according to an embodiment of the present invention.

FIG. 6 is a conceptual diagram showing an example of the configuration of the solid-state imaging element that constitutes the solid-state imaging device of the present embodiment.
As illustrated in FIG. 5, the solid-state imaging device 10 of the present embodiment includes an imaging element 11, an element driving unit 12, a digital signal processor 13, a CPU 14, a memory 15, a bus 16, and a condensing optical system 17. It is out.

  As illustrated in FIG. 6, the imaging device 11 includes a plurality of photodiodes 11a, a transfer gate 11b, a vertical transfer CCD 11c, a horizontal transfer CCD 11d, and a charge / voltage conversion unit 11e.

The photodiodes 11a are arranged vertically and horizontally in a grid pattern, and each converts the received light 20 into a charge amount corresponding to the light amount.
The transfer gate 11b is arranged for each column of the photodiodes 11a, and performs an operation of transferring the charges of the photodiodes 11a to the vertical transfer CCD 11c.

  The vertical transfer CCD 11c is provided for each column in the vertical direction of the photodiode 11a, and performs an operation of sequentially sending out the charges transferred from the photodiode 11a of each column through the transfer gate 11b to the horizontal transfer CCD 11d side.

The horizontal transfer CCD 11d sequentially sends out the charges sent from the vertical transfer CCD 11c of each column to the analog front end 12d of the element driving unit 12 for each column.
The charge / voltage conversion unit 11e converts charges coming from the individual photodiodes 11a into an analog output voltage signal 21 and outputs the analog output voltage signal 21 to the analog front end 12d.

The areas of the transfer gate 11b, the vertical transfer CCD 11c, and the horizontal transfer CCD 11d are shielded from light by a light shielding film or the like.
In addition, among the plurality of photodiodes 11a arranged vertically and horizontally, at least one column (one row) on the outermost periphery is shielded from light to form an optical black portion (pixel). The analog output voltage signal 21 output from the light-shielded photodiode 11a corresponds to the optical black portion.

Photodiodes 11a other than the optical black portion serve as exposure portions (pixels) for imaging.
The analog output voltage signal 21 as image data serially taken out from the vertical row of photodiodes 11a to the analog front end 12d via the vertical transfer CCD 11c and the horizontal transfer CCD 11d has an optical black at the head and rear ends. The image data corresponding to the pixels of the exposure portion is located, and the image data corresponding to the pixels of the exposure portion is located therebetween.

The element driving unit 12 includes a timing generation unit 12a, a vertical driving driver 12b, a horizontal driving driver 12c, and an analog front end 12d.
The timing generation unit 12a operates the vertical drive driver 12b, the horizontal drive driver 12c, and the analog front end 12d in synchronization with each other based on a command from the digital signal processor 13.

  The vertical drive driver 12 b generates a drive clock for the vertical transfer CCD 11 c of the image sensor 11. The horizontal drive driver 12 c generates a drive clock for the analog front end 12 d of the image sensor 11.

  The analog front end 12 d performs noise removal and A / D conversion on the analog output voltage signal 21 coming from the image sensor 11, and outputs a digital output voltage signal 22 as image data to the digital signal processor 13.

  The digital signal processor 13 synchronizes each part of the imaging device 11 and the element driving unit 12 via the timing generation unit 12a. Further, the digital output voltage signal 22 is transferred to the memory 15 via the bus 16.

  The CPU 14 executes the image processing program 30 and the like stored in the memory 15 to control the entire solid-state imaging device 10 and perform processing as illustrated in the flowchart described below.

Hereinafter, an example of the operation of the solid-state imaging device 10 of the present embodiment will be described with reference to the flowchart of FIG.
The memory 15 stores a smear determination threshold Vthob, a linear region saturation voltage value VL (first voltage value), an extended region saturation voltage value Vex (second voltage value), and a saturation voltage Vsat. These values are set in advance from the outside via a user interface or the like.

  In the case of the present embodiment, the saturation voltage Vsat changes according to the value of the OB pixel data value Vob included in the digital output voltage signal 22 coming from the image sensor 11 as will be described later.

  The linear region saturation voltage value VL is the maximum voltage value (boundary with the extended region 21b) of the linear region 21a of the analog output voltage signal 21 in FIG. Normally, this linear region saturation voltage value VL is used as the saturation voltage Vsat.

  The extension region saturation voltage value Vex is the maximum voltage value of the extension region 21b (boundary with the invalid region 21c). In the present embodiment, when smear is detected, this extended region saturation voltage value Vex is used as the saturation voltage Vsat.

  First, the image processing program 30 executed by the CPU 14 reads the digital output voltage signal 22 for one vertical column as image data from the image sensor 11 via the analog front end 12d and the digital signal processor 13 (step 101). (First step), it is determined whether or not the OB pixel data value Vob corresponding to the pixel of the optical black portion at the head of the analog output voltage signal 21 has exceeded the smear determination threshold value Vthob (Vob> Vthob). Step 102) (second step).

When Vob ≦ Vthob, a normal linear region saturation voltage value VL is set as the saturation voltage Vsat (step 108).
If Vob> Vthob in step 102, it is determined whether or not the extended region saturation voltage value Vex (> linear region saturation voltage value VL) has already been set as the saturation voltage Vsat (step 103). If not, the extended region saturation voltage value Vex is set as the saturation voltage Vsat (step 104) (third step).

  Thereafter, in the image processing, the luminance and saturation of the pixel are determined based on the ratio of the digital output voltage signal 22 corresponding to each pixel of the exposure unit to the saturation voltage Vsat, and the image data 23 is output to the memory 15. The image processing (step 105) is performed on the digital output voltage signal 22 corresponding to the pixel of the exposure unit in the column (step 106), and the processing of steps 101 to 106 and step 108 is performed for one frame. This is also applied to all the other columns (step 107).

  Thus, in the present embodiment, when smear is detected in the image data obtained from the image sensor 11, the level of the saturation voltage Vsat is changed from the linear region 21a (linear region saturation voltage value VL) to the extended region 21b ( By extending to the extended region saturation voltage value Vex), the ratio of the smear component Vs occupying the saturation voltage Vsat is relatively reduced, and the image quality deterioration caused by smear in the image data 23 obtained in the memory 15 can be suppressed. Is obtained.

  As a method for reading out the digital output voltage signal 22 from the image sensor 11, one row of pixels is sent from the photodiode 11a in each column in the vertical direction to the horizontal transfer CCD 11d, and the charge / voltage conversion unit 11e is set in units of one row. Via the analog front end 12d.

  In the above example, when smear is detected, the saturation voltage Vsat is discretely changed from the linear region saturation voltage value VL of the linear region 21a to the maximum value (extended region saturation voltage value Vex) of the extended region 21b. However, the saturation voltage Vsat may be varied in the range within the extended region 21b according to the amount of smear.

This example is shown in the flowchart of FIG. In FIG. 8, the same steps as those in FIG. 7 are assigned the same step numbers, and duplicate descriptions are omitted.
That is, instead of step 103 in the flowchart illustrated in FIG. 7, as illustrated in step 201 of the flowchart in FIG. 8, the OB pixel data value Vob corresponding to the pixel of the optical black portion is proportional to the magnitude of the value. The extended region saturation voltage value Vex ′ (second voltage value) is dynamically determined and set as the saturation voltage Vsat (step 103).

  By doing so, it is possible to reduce the amount of change of the saturation voltage Vsat from the original linear region saturation voltage value VL as much as possible, and to suppress smear while maintaining the color carrier balance as much as possible. .

In the above description, the saturation voltage Vsat is changed in units of columns in accordance with the presence or absence of smear. However, the saturation voltage Vsat may be changed in units of frames.
Hereinafter, the example is demonstrated using the flowchart of FIG.

First, image data consisting of the digital output voltage signal 22 for one frame is read from the image sensor 11 (step 301).
Then, the OB pixel data value Vob corresponding to the pixel of the optical black portion included in the first row of the frame is read, and it is determined whether or not the OB pixel data value Vob has exceeded the smear determination threshold value Vthob (step 302). ). In this determination, the determination may be made based on the OB pixel data value Vob of one optical black pixel, or the statistical value of the OB pixel data value Vob for a plurality of pixels is compared with the smear determination threshold value Vthob. Also good.

If it is determined in step 302 that Vob> Vthob, it is determined whether or not the current saturation voltage Vsat has been set to the extended region saturation voltage value Vex (step 303).
If not already set, the set value of the saturation voltage Vsat is changed to the extended region saturation voltage value Vex (step 305), and the digital value of all pixels in the one frame is changed using the changed saturation voltage Vsat. With respect to the output voltage signal 22, the luminance, saturation, and the like of each pixel in the frame are determined at a ratio with respect to the saturation voltage Vsat, and image processing for outputting as the image data 23 is executed (step 305).

  If it is determined in step 302 above that Vob ≦ Vthob, the normal linear region saturation voltage value VL is set as the saturation voltage Vsat (step 307), and the image processing in step 304 is executed.

If the extended region saturation voltage value Vex has already been set as the saturation voltage Vsat in step 303 described above, step 304 is skipped.
Such processing for each frame is applied to all frames sequentially read from the image sensor 11 (step 306).

  As a result, the entire frame in which the smear is detected is image-processed using the saturation voltage Vsat extended to the extended region saturation voltage value Vex, so that the entire image in the frame is uniform so that smear is not noticeable. It is corrected to.

  When processing a plurality of frames continuously, in the first frame, the OB pixel data value Vob is scanned to perform only smear detection determination, and the determination result is applied to image data of subsequent frames. May be.

Needless to say, the present invention is not limited to the configuration exemplified in the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above description, the example in which the processing of the flowcharts illustrated in FIGS. 7, 8, and 9 is performed by the CPU 14 has been described. It is also possible to perform processing by hardware, or to perform processing by the digital signal processor 13.

It is a diagram explaining the principle of the control method of a solid-state imaging device of the present invention, a solid-state imaging device, and an image processing program. It is a graph explaining the principle of the control method of a solid-state imaging device of the present invention, a solid-state imaging device, and an image processing program. It is a diagram explaining the principle of the control method of a solid-state imaging device which is one embodiment of the present invention, a solid-state imaging device, and an image processing program. It is a graph explaining the principle of the control method of the solid-state imaging device which is one embodiment of this invention, a solid-state imaging device, and an image processing program. It is a block diagram which shows an example of a structure of the solid-state imaging device which implements the control method and image processing program of the solid-state imaging device which are one embodiment of this invention. It is a conceptual diagram which shows an example of a structure of the solid-state image sensor which comprises the solid-state imaging device which is one embodiment of this invention. It is a flowchart which shows an example of an effect | action of the control method of a solid-state imaging device which is one embodiment of this invention, and an image processing program. It is a flowchart which shows the modification of the effect | action of the control method and image processing program of a solid-state imaging device which is one embodiment of this invention. It is a flowchart which shows the modification of the effect | action of the control method and image processing program of a solid-state imaging device which is one embodiment of this invention. It is explanatory drawing which shows the image after the smear countermeasure of a reference technique.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Solid-state imaging device 11 Imaging element 11a Photodiode 11b Transfer gate 11c Vertical transfer CCD
11d Horizontal transfer CCD
12 element driver 12a timing generator 12b vertical driver 12c horizontal driver 12d analog front end 13 digital signal processor 14 CPU
15 Memory 16 Bus 17 Condensing optical system 20 Light 21 Analog output voltage signal 21a Linear region 21b Expansion region 21c Invalid region 22 Digital output voltage signal 23 Image data 30 Image processing program OB Vertical VG Image component VL Linear region saturation voltage value Vex Expansion Region saturation voltage value Vex 'Extended region saturation voltage value Vob OB pixel data value Vs Smear component Vsat Saturation voltage Vthob Smear judgment threshold

Claims (14)

A first step of reading image data from the image sensor;
A second step of detecting the presence or absence of smear from the image data;
A third step of setting a saturation voltage value of the imaging device to a second voltage value larger than a first voltage value when the smear is not detected when the smear is detected;
A control method for a solid-state imaging device. In the control method of the solid-state imaging device according to claim 1,
In the second step, the presence or absence of the smear is determined based on whether or not an output voltage as the image data from the optical black portion in the image sensor exceeds a predetermined threshold value. Control method. In the control method of the solid-state imaging device according to claim 1,
In the second step, the presence or absence of the smear is determined based on whether or not the output voltage as the image data from the optical black portion in the image sensor exceeds a predetermined threshold value,
In the third step, the second voltage value set as the saturation voltage is changed in accordance with the magnitude of the output voltage output from the optical black section, and the control method of the solid-state imaging device . In the control method of the solid-state imaging device according to claim 1,
The first voltage value is a value corresponding to the output voltage at the upper limit of a linear region in which an exposure amount with respect to the image sensor and an output voltage as the image data from the image sensor are substantially proportional.
The method of controlling a solid-state imaging device, wherein the second voltage value is set to the output voltage in an extended region exceeding the linear region. In the control method of the solid-state imaging device according to claim 1,
The method for controlling a solid-state imaging device further includes a fourth step of determining luminance or saturation of a pixel corresponding to the output voltage as a ratio of the output voltage to the saturation voltage. A solid-state imaging device comprising: imaging means for converting light into voltage; and image processing means for configuring an image based on the voltage,
The image processing means determines the presence or absence of smear based on whether or not the voltage output from the optical black portion in the imaging means exceeds a predetermined threshold, and the image pick-up is performed when the smear is detected. A solid-state imaging device including a function of setting a saturation voltage value of an element to a second voltage value larger than a first voltage value when the smear is not detected. The solid-state imaging device according to claim 6.
The solid-state imaging device, wherein the image processing unit changes the second voltage value set as the saturation voltage according to the magnitude of the output voltage output from the optical black unit. The solid-state imaging device according to claim 6.
The first voltage value is a value corresponding to the output voltage at the upper limit of a linear region in which the exposure amount with respect to the imaging unit and the output voltage from the imaging device are substantially proportional,
The solid-state imaging device, wherein the second voltage value is set in an extended region exceeding the linear region. The solid-state imaging device according to claim 8.
The solid-state imaging device, wherein the image processing means determines a luminance or saturation of a pixel corresponding to the output voltage as a ratio of the output voltage to the saturation voltage. An image processing program for controlling a solid-state imaging device including an imaging element and a computer that processes image data output from the imaging element,
In the computer,
A first step of reading image data from the image sensor;
A second step of detecting the presence or absence of smear from the image data;
A third step of setting a saturation voltage value of the imaging device to a second voltage value larger than a first voltage value when the smear is not detected when the smear is detected;
An image processing program for executing The image processing program according to claim 10.
In the second step, the presence or absence of the smear is determined based on whether or not an output voltage as the image data from the optical black portion in the image sensor exceeds a predetermined threshold value. . The image processing program according to claim 10.
In the second step, the presence or absence of the smear is determined based on whether or not the output voltage as the image data from the optical black portion in the image sensor exceeds a predetermined threshold value,
In the third step, the second voltage value set as the saturation voltage is changed according to the magnitude of the output voltage output from the optical black section. The image processing program according to claim 10.
The first voltage value is a value corresponding to the output voltage at the upper limit of a linear region in which an exposure amount with respect to the image sensor and an output voltage as the image data from the image sensor are substantially proportional.
The image processing program according to claim 1, wherein the second voltage value is set to the output voltage in an extended region exceeding the linear region. The image processing program according to claim 10.
An image processing program that causes the computer to execute a process of determining luminance or saturation of a pixel corresponding to the output voltage as a ratio of the output voltage to the saturation voltage.