CN117319817A

CN117319817A - Image sensor and method of operating the same

Info

Publication number: CN117319817A
Application number: CN202311141314.9A
Authority: CN
Inventors: 张斌; 罗毅; 邓志鹏; 刘俊哲
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2023-09-05
Filing date: 2023-09-05
Publication date: 2023-12-29

Abstract

The embodiment of the application provides an image sensor and an operation method thereof, relates to the technical field of sensors, and solves the problem of poor imaging quality of the image sensor. The specific scheme is as follows: the image sensor includes a pixel array, a readout circuit, a memory, and an equalizer. The output of the pixel array is coupled to the input of the readout circuit, the output of the readout circuit is coupled to the memory, and the memory is further coupled to the input of the equalizer. The pixel array is used for converting the received optical signal into an electrical signal. The readout circuit is used for converting the electrical signals into pixel signals, and the pixel signals are used for representing intensity values of pixel points of the pixel array. The memory is used for storing pixel signals. The equalizer comprises a filter, wherein the filter is used for reading the pixel signals from the memory, and performing equalization processing on the pixel signals, and the difference value between the intensity value of the pixel signals after the equalization processing and the intensity value of the adjacent pixel signals is smaller than a preset value. The embodiment of the application is used for the image processing process of the image sensor.

Description

Image sensor and method of operating the same

Technical Field

The embodiment of the application relates to the technical field of sensors, in particular to an image sensor and an operation method thereof.

Background

With the development of machine vision and artificial intelligence (artificial intelligence, AI), further demands are made on the performance of cameras, and thus new challenges are presented to the performance of image sensors. The imaging quality of image sensors is an important indicator in the vehicle field, the industrial application field and the consumer field.

However, the image output by the existing image sensor is often subjected to horizontal and vertical stripes, oblique stripes, molar stripes and the like after being processed, so that the imaging quality of the image sensor is affected. Thus, how to improve the imaging quality of the image sensor is called a problem to be solved.

Disclosure of Invention

The embodiment of the application provides an image sensor and an operation method thereof, which improve the problem of poor imaging quality of the image sensor.

In order to achieve the above purpose, the following technical solutions are adopted in the embodiments of the present application.

In a first aspect, embodiments of the present application provide an image sensor that includes a pixel array, a readout circuit, a memory, and an equalizer. The output of the pixel array is coupled to the input of the readout circuit, the output of the readout circuit is coupled to the memory, and the memory is further coupled to the input of the equalizer. The pixel array is used for converting the received optical signal into an electrical signal. The readout circuit is used for converting the electrical signals into pixel signals, and the pixel signals are used for representing intensity values of pixel points of the pixel array. The memory is used for storing pixel signals. The equalizer comprises a filter, wherein the filter is used for reading the pixel signals from the memory, and performing equalization processing on the pixel signals, and the difference value between the intensity value of the pixel signals after the equalization processing and the intensity value of the adjacent pixel signals is smaller than a preset value.

Therefore, the image sensor provided by the embodiment of the application comprises an equalizer, and before the pixel signals are transmitted to the subsequent digital signal processing unit, the pixel signals are subjected to equalization processing by using a filter in the equalizer, and the difference value between the intensity values of the pixel signals after the equalization processing and the intensity values of the adjacent pixel signals is smaller than a preset value. Therefore, the stripes of the image processed by the digital signal processing unit can be effectively reduced, and the imaging quality of the image sensor is improved.

In one possible design, the equalizer further includes a weight matcher, an output of the weight matcher coupled to an input of the filter. The weight matcher is used for matching different weights according to the intensity values of different pixel points. The filter is specifically configured to read the pixel signals from the memory and perform filtering processing on the pixel signals to different extents according to different weights, so as to achieve pixel signal equalization.

In the design, the weight matcher can match different weights according to the intensity values of different pixel points, namely, the filter processing with larger intensity can be carried out on the pixel signal with the worst equalization, and the filter processing with smaller intensity can be carried out on the pixel signal with the worse equalization.

In one possible design, the filter is specifically configured to read the pixel signal of the pixel point of the preset area from the memory, and perform the filtering process on the pixel signal of the pixel point of the preset area based on the first weight when the pixel signal of the pixel point of the preset area is greater than the preset threshold.

In the design, the pixel signals of the pixel points in the preset area are larger than the preset threshold, namely the average intensity value of all the pixel points in the preset area is larger than the preset threshold, and the pixel signals of the pixel points in the preset area can be subjected to larger-intensity filtering, so that the balance of the pixel signals can be improved, and the imaging quality of the image sensor is improved.

In one possible design, the filter is further specifically configured to perform filtering processing on the pixel signal of the pixel point of the preset area based on the second weight when the pixel signal of the pixel point of the preset area is less than or equal to the preset threshold, where the first weight is greater than the second weight.

In the design, the pixel signals of the pixel points in the preset area are smaller than or equal to a preset threshold, namely the average intensity value of all the pixel points in the preset area is smaller than or equal to the preset threshold, and the pixel signals of the pixel points in the preset area can be subjected to filtering processing with smaller intensity, so that the balance of the pixel signals can be improved, and the imaging quality of the image sensor can be improved.

In one possible design, the weight matcher includes a trigger and a switch; the input end of the trigger is coupled with the input end of the equalizer, the output end of the trigger is coupled with the control end of the switch, the first end of the switch is coupled with the input end of the equalizer, the second end of the switch is coupled with the output end of the equalizer, the first end of the filter is coupled with the input end of the equalizer, and the second end of the filter is coupled with the output end of the equalizer. The trigger is used for controlling the switch to be turned off when the pixel signal of the pixel point of the preset area is larger than a preset threshold value. The trigger is also used for controlling the switch to be turned on when the pixel signal of the pixel point of the preset area is smaller than or equal to a preset threshold value. The filter is used for carrying out filtering processing on pixel signals of pixel points of a preset area based on the first weight when the switch is turned off.

In the design, the trigger can control the switch to be turned on or off, when the switch is turned off, the filter performs filtering processing with larger intensity on the pixel signal, and when the switch is turned on, the pixel signal can be transmitted through the switch, and at the moment, the filter does not perform filtering processing on the pixel signal. Therefore, the pixel signals can be subjected to filtering processing to different degrees, the balance of the pixel signals can be improved, and the imaging quality of the image sensor can be improved.

In one possible design, the pixel array includes at least three pixel points, and the filter is specifically configured to obtain the number of each pixel point in the preset area. And filtering the pixel signals of each pixel point based on a filtering proportion, wherein the filtering proportion is stored in a page table.

In the design, parameters of the filter for filtering treatment can be calibrated in advance, and the filtering proportion is obtained and stored in a page table. Therefore, in the use process of the image sensor, pixel signals can be subjected to equalization processing, the conditions of stripes and the like of an output image of the image sensor can be improved, and the imaging quality of the image sensor can be improved.

In one possible design, the preset value is related to the intensity value at which the pixel signal is calibrated.

In the design, the reasonable preset value is set, so that the balance of pixel signals can be improved, the conditions of stripes and the like of an output image of the image sensor are improved, and the imaging quality of the image sensor is improved.

In one possible design, when the pixel signal is a digital signal, the readout circuit includes a first electronic voltage converter and a first analog-to-digital converter. The first electronic voltage converter is used for converting the electric signal into an analog signal. The first analog-to-digital converter is used for converting the analog signal into a digital signal.

In the design, if the pixel signal is a digital signal, the filter can be a digital filter, so that the circuit of the equalizer is simplified, the integration level of the equalizer is high, and the high-precision and high-reliability filtering process can be provided.

In one possible design, when the pixel signal is a voltage signal, the readout circuit includes: the second electronic voltage converter, the image sensor further includes: and the input end of the second analog-to-digital converter is coupled with the output end of the equalizer. The electronic voltage converter is used for converting the electric signal into a voltage signal. The second analog-to-digital converter is used for converting the pixel signal into a digital signal.

In this design, if the pixel signal is a voltage signal, the filter may be an analog filter, which may eliminate various harmonics in the pixel signal and provide a high-precision filtering process.

In one possible design, when the pixel signal is a current signal, the readout circuit includes an electronic current converter, and the image sensor further includes: the current-to-voltage converter and the third analog-to-digital converter, the input end of the current-to-voltage converter is coupled with the output end of the equalizer, and the output end of the current-to-voltage converter is coupled with the input end of the third analog-to-digital converter. The electronic current converter is used for converting the electric signal into a current signal. The current-voltage converter is used for converting a current signal into a voltage signal. The third analog-to-digital converter is used for converting the voltage signal into a digital signal.

In this design, if the pixel signal is a current signal, the filter may be an analog filter, which may eliminate various harmonics in the pixel signal and provide a high-precision filtering process.

In a second aspect, embodiments of the present application provide a method of operating an image sensor that includes a pixel array, a readout circuit, a memory, and an equalizer. The output of the pixel array is coupled to the input of the readout circuit, the output of the readout circuit is coupled to the memory, the memory is further coupled to the input of the equalizer, and the equalizer comprises a filter. The method comprises the following steps: the pixel array is controlled to convert the received optical signal into an electrical signal. The control readout circuitry converts the electrical signals into pixel signals that are used to characterize the intensity values of the pixel points of the pixel array. The control memory stores pixel signals. The control filter reads the pixel signals from the memory, and performs equalization processing on the pixel signals, wherein the difference value between the intensity value of the pixel signals after the equalization processing and the intensity value of the adjacent pixel signals is smaller than a preset value.

The advantages of the second aspect may be seen from the description of the first aspect.

In one possible design, the equalizer further includes a weight matcher, an output of the weight matcher coupled to an input of the filter. The method further comprises the steps of: and controlling the weight matcher to match different weights according to the intensity values of different pixel points. Controlling the filter to read the pixel signals from the memory and to perform an equalization process on the pixel signals, comprising: the control filter reads the pixel signals from the memory and performs filtering processing on the pixel signals to different degrees according to different weights so as to realize pixel signal equalization.

In one possible design, controlling the filter to read the pixel signals from the memory and to perform different degrees of filtering on the pixel signals according to different weights includes: and the control filter reads the pixel signals of the pixel points of the preset area from the memory, and when the pixel signals of the pixel points of the preset area are larger than a preset threshold value, the pixel signals of the pixel points of the preset area are subjected to equalization processing based on the first weight.

In one possible design, the control filter reads the pixel signals from the memory and performs filtering processing on the pixel signals to different degrees according to different weights, and the control filter further includes: and controlling the equalizer to perform filtering processing on the pixel signals of the pixel points of the preset area based on the second weight when the pixel signals of the pixel points of the preset area are smaller than or equal to a preset threshold value, wherein the first weight is larger than the second weight.

In one possible design, the weight matcher includes a trigger and a switch; the input end of the trigger is coupled with the input end of the equalizer, the output end of the trigger is coupled with the control end of the switch, the first end of the switch is coupled with the input end of the equalizer, the second end of the switch is coupled with the output end of the equalizer, the first end of the filter is coupled with the input end of the equalizer, and the second end of the filter is coupled with the output end of the equalizer. The control filter reads pixel signals of the pixel points of the preset area from the memory, and when the pixel signals of the pixel points of the preset area are larger than a preset threshold value, the filter processing is performed on the pixel signals of the pixel points of the preset area based on the first weight, and the filter processing comprises the following steps: when the pixel signals of the pixel points in the preset area are larger than a preset threshold value, the control trigger is controlled to be turned off, so that the filter is controlled to carry out filtering processing on the pixel signals of the pixel points in the preset area based on the first weight. When the pixel signal of the pixel point of the preset area is smaller than or equal to a preset threshold value, the control filter performs filtering processing on the pixel signal of the pixel point of the preset area based on the second weight, and the control filter comprises the following steps: when the pixel signals of the pixel points in the preset area are smaller than or equal to a preset threshold value, the control trigger controls the switch to be turned on so as to control the filter to carry out filtering processing on the pixel signals of the pixel points in the preset area based on the second weight.

In one possible design, the pixel array includes at least three pixel points, and the control filter performs an equalization process on pixel signals of the pixel points in the preset area, including: the control filter obtains the number of each pixel point of the pixel array in the preset area. The control filter performs filtering processing on the pixel signals of each pixel point based on a filtering proportion, and the filtering proportion is stored in a page table.

In one possible design, when the pixel signal is a digital signal, the readout circuit includes: a first electronic voltage converter and a first analog-to-digital converter. The control readout circuit converts the electrical signal into a pixel signal, comprising: the first electronic voltage converter is controlled to convert the electric signal into an analog signal. The first analog-to-digital converter is controlled to convert the analog signal into a digital signal.

In one possible design, when the pixel signal is a voltage signal, the readout circuit includes: the second electronic voltage converter, the image sensor further includes: and the input end of the second analog-to-digital converter is coupled with the output end of the equalizer. The control readout circuit converts the electrical signal into a pixel signal, comprising: the electronic voltage converter is controlled to convert the electrical signal into a voltage signal. The method further comprises the steps of: the second analog-to-digital converter is controlled to convert the pixel signal into a digital signal.

In one possible design, when the pixel signal is a current signal, the readout circuit includes: the electron current converter, the image sensor further includes: the current-to-voltage converter and the third analog-to-digital converter, the input end of the current-to-voltage converter is coupled with the output end of the equalizer, and the output end of the current-to-voltage converter is coupled with the input end of the third analog-to-digital converter. The control readout circuit converts the electrical signal into a pixel signal, comprising: the electronic current converter is controlled to convert the electrical signal into a current signal. The method further comprises the steps of: the current-to-voltage converter is controlled to convert the current signal into a voltage signal, and the third analog-to-digital converter is controlled to convert the voltage signal into a digital signal.

In a third aspect, embodiments of the present application provide a graphics processing apparatus, including: a lens, an image sensor of the first aspect, and a processor. The lens is used for receiving the optical signals, and the processor is used for processing the pixel signals transmitted by the image sensor.

In a fourth aspect, embodiments of the present application provide a computer device comprising a processor and a memory for storing a set of computer instructions. The method of the second aspect is performed when a processor executes a set of computer instructions.

In a fifth aspect, embodiments of the present application provide a computer-readable storage medium including computer instructions that, when executed on an electronic device, cause the electronic device to perform the method of operating an image sensor in any one of the above aspects and any one of the possible implementations.

In a sixth aspect, embodiments of the present application provide a computer program product which, when run on a computer or processor, causes the computer or processor to perform the method of operating an image sensor of any one of the above aspects and any one of the possible implementations.

It is to be understood that any of the image sensor, the graphics processing apparatus, the computer readable storage medium, the computer program product, etc. provided above may be applied to the corresponding method provided above, and thus, the advantages achieved by the method may refer to the advantages in the corresponding method, which are not described herein.

These and other aspects of the present application will be more readily apparent from the following description.

Drawings

FIG. 1 is a schematic diagram of interpolation of an RGBW array according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of pixel array conversion according to an embodiment of the present disclosure;

Fig. 3 is an internal frame diagram of an execution device according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of an image sensor according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a different type of pixel array according to an embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of another image sensor according to an embodiment of the present disclosure;

fig. 7 is a schematic structural diagram of another image sensor according to an embodiment of the present disclosure;

fig. 8 is a schematic structural diagram of another image sensor according to an embodiment of the present disclosure;

fig. 9 is a schematic structural diagram of another image sensor according to an embodiment of the present disclosure;

FIG. 10 is a flowchart of a method of operating an image sensor according to an embodiment of the present disclosure;

FIG. 11 is a comparison of images provided in embodiments of the present application;

fig. 12 is a schematic structural diagram of a graphics processing apparatus according to an embodiment of the present application.

Detailed Description

For ease of understanding, an illustration of some of the concepts related to the embodiments of the present application is given by way of example for reference. The following is shown:

an analog-to-digital converter (analog to digital converter, ADC), a converter that converts an analog quantity subjected to comparison processing with a standard quantity (or reference quantity) into a discrete signal represented by a binary value.

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Wherein, in the description of the embodiments of the present application, "/" means or is meant unless otherwise indicated, for example, a/B may represent a or B; "and/or" herein is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, in the description of the embodiments of the present application, "plurality" means two or more than two.

The terms "first" and "second" are used below for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present embodiment, unless otherwise specified, the meaning of "plurality" is two or more.

Currently, an image processing apparatus is proposed, which includes a signal processing unit that performs pixel value compensation. Wherein the signal processing unit comprises an RGBW array of each color pixel of red (red, R), green (G), blue (B) and white (W), wherein the RGBW array can receive optical signals of almost all wavelengths. Within the reference region, the signal processing unit inserts W pixels based on the positions of the target pixels as compensation targets and the positions of the reference pixels having the same color as the target pixels, and then calculates smoothing weights based on the respective pixel values of the inserted W pixels, thereby calculating compensation pixel values of the target pixels by performing smoothing processing to which the calculated smoothing weights are applied. Further, whether the color pixel is within the texture region is determined by applying the W pixel in the vicinity of the color pixel, and the defect compensation process is performed as long as the color pixel is not within the texture region. As shown in fig. 1, fig. 1 is a schematic diagram illustrating interpolation of an RGBW array according to an embodiment of the present application. The W0, W1, W2, W3, and W4 pixels are inserted at positions of the pixel of interest and the reference pixel by setting a reference region (for example, 7x7 pixels) whose center is any one of the R, G and B color pixels as a compensation target. Specifically, the interpolation pixel W0 is allocated to a position of a pixel of interest as a compensation target located at the center of the reference area, and four interpolation W pixels W1 to W4 are allocated to a 7x7 pixel reference area in the vicinity of the pixel of interest. However, the image processing apparatus can perform noise reduction processing and defect compensation processing only on imaging of the image sensor, which may still occur as streaks or the like.

In addition to this, another image processing apparatus is proposed, which includes an image sensor and an image processing unit. Wherein the image sensor has an RGBW array including RGB pixels, which are light receiving elements for each RGB color of wavelength light, and W pixels, which are light receiving elements for receiving all RGB wavelength light. The image processing unit performs image processing by inputting a sensor image formed of RGBW pixel signals output from an image sensor. The image sensor has a periodic array of unit compositions formed of each RGBW pixel, and has an array in which the composition ratio of each RGB pixel within the unit composition is adapted to be identical to each other. The image processing unit converts a pixel array of a sensor image formed of RGBW pixel signals, and performs an array conversion process for generating an RGB array image or generates each RGB image signal in which all RGB pixel values are set for each pixel position of the sensor image.

Fig. 2 is a schematic diagram of pixel array conversion according to an embodiment of the present application, as shown in fig. 2. As shown in (a) of fig. 2, the first row repeats rwgwbwgw, the second row repeats WRWGWB, the third row repeats GWBWRW, the fourth row repeats WGWBWR, the fifth row repeats bwrgw, and the sixth row repeats WBWRWG, and the first row to the sixth row are repeated from the seventh row. Wherein each row and each column is configured such that: one W pixel is interposed therebetween, and each RGB pixel is sequentially arranged. The image processing apparatus converts the RGBW array shown in (a) in fig. 2, generating a bayer array image shown in (b) in fig. 2, wherein the bayer array image does not include W pixels. The image apparatus may perform signal processing such as conventional camera signal processing (white balance adjustment, gamma correction, mosaic processing, and the like) on an image output by the bayer array, and generate an output image. However, in this image processing apparatus, only an RGB image having less color noise or less false color can be generated, and the imaging of the image sensor may still occur in the case of streaks or the like.

Thus, embodiments of the present application provide an image sensor that may include a pixel array, readout circuitry, memory, and an equalizer. Before the pixel signals are transmitted to the subsequent digital signal processing unit, the filter in the equalizer is used for carrying out equalization processing on the pixel signals, and the difference value between the intensity values of the pixel signals after the equalization processing and the intensity values of the adjacent pixel signals is smaller than a preset value, so that the fringes of the image processed by the digital signal processing unit can be effectively reduced, and the imaging quality of the image sensor is improved.

In the above scenario, the image sensor of the embodiments of the present application may be applied to different systems or devices, such as an execution device, where the execution device may be a terminal, such as a mobile phone terminal, a tablet computer, a notebook, an augmented reality (augmented reality, AR) device, a Virtual Reality (VR) device, an in-vehicle terminal, and so on. The execution device may acquire a target image through the image sensor, and process and display the image.

As shown in fig. 3, fig. 3 is an internal frame diagram of an execution device according to an embodiment of the present application. The execution device may include an image sensor, a digital signal processor (digital signal processing, DSP), a system-on-a-chip (SoC), a memory, a display, and the like. Wherein the memory may comprise: read Only Memory (ROM) and random access memory (random access memory, RAM). The target image acquired by the image sensor can be transmitted to a digital signal processor through a mobile industry processor interface (mobile industry processor interface, MIPI), and the digital signal processor and a subsequent system-in-chip perform target image processing. The system chip can store the processed target image into a memory, and can also transmit the processed target image to a display for display.

The image sensor provided in the embodiments of the present application is further described below.

An embodiment of the present application provides an image sensor, as shown in fig. 4, and fig. 4 is a schematic structural diagram of the image sensor provided in the embodiment of the present application. The image sensor 40 may include a pixel array (pixel array) 41, a readout circuit 42, a memory 43, and an equalizer 44. The output of the pixel array 41 is coupled to an input of a readout circuit 42, the output of the readout circuit 42 is coupled to a memory 43, and the memory 43 is further coupled to an input of an equalizer 44.

Wherein the pixel array 41 is used for converting a received optical signal into an electrical signal.

The pixel array 41 may be implemented as a photoelectric conversion device, such as a charge coupled device (charge coupled device, CCD) or a complementary metal oxide semiconductor (complementary metal oxide semiconductor, CMOS), for example. The pixel array 41 may include a plurality of pixel dots arranged in an array, and the pixel dots may convert received optical signals into electrical signals. Each pixel may include a light sensing device, which in one example may include a photodiode, an organic photodiode, a phototransistor, a photogate, or a pinned photodiode.

Specifically, as shown in fig. 5, fig. 5 is a schematic diagram of a different type of pixel array according to an embodiment of the present application. As shown in fig. 5 (a), the pixel array 41 may include an RGB array, which may be understood as a color filter array, which may assist in capturing color information (i.e., wavelengths) of the received light signal while capturing intensity values of the received light signal. The RGB array records the intensity values of the light signals according to the pixel points of the color arrangement, and the subsequent digital signal processor and the like can restore color information based on the intensity values of the light signals of the three primary colors. As shown in fig. 5 (b), in order to increase the light entering amount of the image sensor 40, the pixel array 41 may also be an RGBW array, wherein the W pixel may receive white light (i.e., global light). As shown in (c) of fig. 5, in order to improve the color vividness of the image formed by the image sensor 40, the number of G pixel points may be increased, and the pixel array 41 may be an RGGB array or the like. As shown in (d) of fig. 5, in order to increase the light entering amount of the image sensor 40, the G pixel point may be replaced with a yellow (Y) pixel point, and the pixel array 41 may be a RYYB array. It will be appreciated that the pixel array 41 may be of other types, and the embodiments of the present application do not specifically limit the types of the pixel array 41.

The readout circuit 42 is configured to convert the electrical signal into a pixel signal, where the pixel signal is used to characterize an intensity value of a pixel point of the pixel array 41.

For example, the pixel signal may include an intensity value of the pixel, which may also be understood as brightness, i.e. the degree of darkness of the color. Assuming that the color information of each pixel is represented in a 12-bit binary representation (i.e., a 12-bit map), the pixel can express 12 th power of 2, i.e., 4096 kinds of color information. Assuming that the color information of each pixel is represented in 16-bit binary (i.e., 16-bit map), the pixel can express the 16 th power of 2, i.e., 65536 kinds of color information. The actual intensity value of a certain pixel point is the sum of the intensity value of the pixel point and the intensity value generated by the influence of the adjacent pixel points on the pixel point, wherein the intensity value of the position which is closer to the pixel point is larger, and the intensity value of the position which is farther from the pixel point is smaller.

In particular, the pixel signal may be in the form of a digital signal or an analog signal. If the pixel signal is a digital signal, the readout circuit 42 may be a conversion device that converts an electrical signal into a digital signal. If the pixel signal is a voltage signal, the readout circuit 42 may be a conversion device that converts an electrical signal into a voltage signal. If the pixel signal is a current signal, the readout circuit 42 may be a conversion device that converts an electrical signal into a current signal.

Wherein the memory 43 is used for storing pixel signals.

The memory 43 may be, for example, a buffer (buffer) for temporarily storing the pixel signals from the readout circuit 42 for equalizing the pixel signals by the subsequent equalizer 44. Specifically, the memory 43 may be a dynamic random access memory (dynamic random access memory, DRAM), a static random access memory (static random access memory, SRAM), a flash memory (flash), or the like.

The equalizer 44 includes a filter 441, where the filter 441 is configured to read the pixel signal from the memory 43, and perform an equalization process on the pixel signal, and a difference between an intensity value of the pixel signal after the equalization process and an intensity value of an adjacent pixel signal is smaller than a preset value.

Illustratively, the filter 441 may read all pixel signals from the memory 43, and the filter may read some pixel signals from the memory 43 in batches.

The pixel signal includes a high-frequency unbalanced signal, that is, a difference between the intensity values of the high-frequency unbalanced signal and the adjacent pixel signal is greater than or equal to a preset value. The preset value is related to the intensity value calibrated by the pixel signal. In one example, the preset value may be set to be larger if the intensity value of the pixel signal calibration is larger, and smaller if the intensity value of the pixel signal calibration is smaller.

The filter 441 performs an equalization process on the pixel signal, that is, reduces the intensity value of the high-frequency unbalanced signal in the pixel signal, so that the intensity value of the high-frequency unbalanced signal and the intensity value of the adjacent pixel signal are smaller than a preset value, thereby realizing the equalization of the pixel signal. The target pixel signal is assumed to include four-directional neighboring pixel signals, namely, an upper neighboring pixel signal, a lower neighboring pixel signal, a left neighboring pixel signal, and a right neighboring pixel signal. In one example, the filter 441 may obtain the maximum value of the adjacent pixel signals in four directions, and then may filter the intensity value of the target pixel signal to the sum of the maximum value and the preset value. In another example, the magnitudes of a first difference between the upper and lower adjacent pixel signals and a second difference between the left and right adjacent pixel signals may be determined, and if the first difference is less than or equal to the second difference, the intensity value of the target pixel signal may be filtered to half the sum of the upper and lower adjacent pixel signals. If the first difference is greater than the second difference, the intensity value of the target pixel signal may be filtered to half the sum of the left and right adjacent pixel signals.

Therefore, after the equalizer equalizes the pixel signals, the stripes of the image processed by the digital signal processing unit can be effectively reduced, and the imaging quality of the image sensor is improved.

Optionally, as shown in fig. 6, equalizer 44 may further include a weight matcher 442, with an output of weight matcher 442 coupled to an input of filter 441. The weight matcher 442 is configured to match different weights according to intensity values of different pixels. In addition, the filter 441 is configured to read the pixel signals from the memory, and perform filtering processing on the pixel signals to different extents according to different weights, so as to achieve pixel signal equalization.

Illustratively, different weights may characterize the filtering of the pixel signal to different extents, and in one example, if the weight matcher 442 matches the largest weight for the current pixel signal, the filter 441 performs the greatest degree of filtering on the current pixel signal. If the weight matching 442 matches the current pixel signal with the smallest weight, where the smallest weight may be that the current pixel signal is not processed, the filter 441 may directly transmit the current pixel signal to the subsequent digital signal processing unit without performing filtering processing on the current pixel signal.

Specifically, the filter 441 is configured to read a pixel signal of a pixel of a preset area from the memory 43, and perform filtering processing on the pixel signal of the pixel of the preset area based on the first weight when the pixel signal of the pixel of the preset area is greater than a preset threshold. In addition, the filter 441 is configured to perform a filtering process on the pixel signal of the pixel point of the preset area based on the second weight when the pixel signal of the pixel point of the preset area is less than or equal to the preset threshold. Wherein the first weight is greater than the second weight.

For example, the preset area may also be referred to as a sliding window area, wherein the preset area may include at least two pixel points. In one example, the preset area may include 2-40000 pixel points. The size of the preset area may be related to the accuracy of the equalization process, wherein the larger the preset area, the higher the accuracy of the equalization process, and the better the imaging quality of the image sensor 40. The preset areas at different moments can be overlapped or not, and the accuracy of the equalization processing can be improved by increasing the overlapping degree of the preset areas.

By way of example, the first weight may be understood as a filtering process of greater intensity on the pixel signal and the second weight may be understood as a filtering process of lesser intensity on the pixel signal.

For example, the preset threshold may be an intensity value, and the pixel signal of the pixel point in the preset area is greater than the preset threshold, that is, the average intensity value of all the pixel points in the preset area is greater than the preset threshold, that is, the preset area includes a high-frequency imbalance signal. Thus, the pixel signals of the pixel points in the preset area can be subjected to filtering processing with larger intensity.

The pixel signal of the pixel point in the preset area is smaller than or equal to the preset threshold value, which is the preset area, that is, the average intensity value of all the pixel points in the preset area is smaller than or equal to the preset threshold value, that is, the preset area includes less or no high-frequency unbalanced signal. Thus, the pixel signals of the pixel points in the preset area can be subjected to filtering processing with smaller intensity.

Optionally, with continued reference to fig. 6, the weight matcher 442 may include a flip flop (flip flop) 4421 and a switch 4422. An input of the flip-flop 4421 is coupled to an input of the equalizer 44, an output of the flip-flop 4421 is coupled to a control of the switch 4422, a first end of the switch 4422 is coupled to an input of the equalizer 44, a second end of the switch 4422 is coupled to an output of the equalizer 44, a first end of the filter 441 is coupled to an input of the equalizer 44, and a second end of the filter 441 is coupled to an output of the equalizer 44.

The trigger 4421 is configured to control the switch 4422 to be turned off when a pixel signal of a pixel point in the preset area is greater than a preset threshold. The filter 441 performs a filtering process on the pixel signals of the pixels of the preset area based on the first weight when the switch 4422 is turned off.

The trigger 4421 is further configured to control the switch 4422 to be turned on when a pixel signal of a pixel point in the preset area is less than or equal to a preset threshold.

By way of example, flip-flop 4421 may be an electronic circuit having two stable states that may be used to store binary data, which may be altered using different inputs. In particular, the two stable states may include a high level and a low level. The switch 4422 may be a transistor (transistor), taking the switch 4422 as an N-type metal oxide semiconductor (negative channel metal oxide semiconductor, NMOS) as an example, the source of the NMOS is the first terminal of the switch 4422, the drain of the NMOS is the second terminal of the switch 4422, and the gate of the NMOS is the control terminal of the switch 4422. If the output terminal of the flip-flop 4421 outputs a high level, the NMOS is turned on, and the pixel signal can be transmitted to the subsequent digital signal processing unit through the NMOS. If the output terminal of the flip-flop 4421 outputs a low level, the NMOS is turned off, the pixel signal is transmitted to the filter 441, and the filter 441 may perform a filtering process on the pixel signal based on the first weight.

Optionally, the pixel array 41 includes at least three pixel points, and the filter 441 is specifically configured to obtain the number of each pixel point in the preset area, perform filtering processing on the pixel signal of each pixel point based on a filtering proportion, where the filtering proportion is stored in the page table.

The filtering ratio may be obtained by calibration, in which the imbalance of the pixel signal is calibrated, a set of array data is generated after calibration and fitting, and the weighted balance calibration is performed by the generated array data. In addition, the equalizer can calculate the difference between the same pixels by referring to the change of the pixel signal to be equalized and the change of the adjacent pixel signal, and then perform the equalization processing, so that the filtering ratio can be obtained, and the filtering ratio forming table is written into the one-time programmable (one time programmable, OTP). Wherein the signal frequency, weight and equalization range of equalizer 44 may be adjusted.

Specifically, taking the pixel array 41 as an RGBW array as an example, the specific steps of the filter 441 performing the filtering process may include: (1) And respectively counting the number of R pixel points, G pixel points, B pixel points and W pixel points in a preset area. (2) The statistical value ratio of the G pixel point, the B pixel point and the R pixel point is calculated, the page table in the memory 43 is searched to obtain the filtering ratio, and the filtering processing is performed on the W pixel point based on the filtering ratio. (3) And calculating the statistical value proportion of the W pixel point, the B pixel point and the R pixel point, searching a page table in the memory 43 to obtain a filtering proportion, and carrying out filtering processing on the G pixel point based on the filtering proportion. (4) The statistical value ratio of the G pixel point, the W pixel point and the R pixel point is calculated, the page table in the memory 43 is searched to obtain the filtering ratio, and the filtering processing is performed on the B pixel point based on the filtering ratio. (5) The statistical value ratio of the G pixel point, the B pixel point and the W pixel point is calculated, the page table in the memory 43 is searched to obtain the filtering ratio, and the R pixel point is subjected to filtering processing based on the filtering ratio.

In addition, taking the pixel array 41 as an RGB array as an example, the specific steps of the filter 441 to execute the filtering processor may include: (1) And respectively counting the number of R pixel points, G pixel points and B pixel points in a preset area. (2) The statistical value ratio of the G pixel point and the B pixel point is calculated, the page table in the memory 43 is searched to obtain the filtering ratio, and the R pixel point is subjected to filtering processing based on the filtering ratio. (3) The statistical value ratio of the R pixel point and the B pixel point is calculated, the page table in the memory 43 is searched to obtain the filtering ratio, and the filtering processing is performed on the G pixel point based on the filtering ratio. (4) The statistical value ratio of the G pixel point and the R pixel point is calculated, the page table in the memory 43 is searched to obtain the filtering ratio, and the filtering processing is performed on the B pixel point based on the filtering ratio.

Thus, the high-frequency unbalanced signal in the preset area can be eliminated, the pixel signals of each pixel point can be balanced, and the imaging quality of the image sensor 40 can be improved.

Optionally, the image sensor 40 may further comprise a digital processing module 45 and an interface 46, wherein the interface 46 may be a MIPI interface.

Illustratively, the digital processing module 45 may perform preliminary processing on the output signal of the equalizer output and transmit it to the digital signal processing unit via the interface 46.

If the pixel signal is a digital signal, as shown in fig. 7, fig. 7 is a schematic structural diagram of another image sensor according to an embodiment of the present application. The readout circuit 42 may include a first electronic voltage converter 421 and a first analog-to-digital converter 422. The first electronic voltage converter 421 is configured to convert an electrical signal into an analog signal, and the first analog-to-digital converter 422 is configured to convert the analog signal into a digital signal.

Specifically, the pixel array 41 may convert the received optical signal into an electrical signal, the electrical signal may be converted into a voltage signal by the first electronic voltage converter 421, the voltage signal may be converted into a digital signal by the first analog-to-digital converter 422, and the digital signal may be stored in the memory 43. The equalizer 44 reads the pixel signal of the preset area from the memory 43, and if the average intensity value represented by the digital signal in the preset area is greater than the preset threshold value, the trigger 4421 triggers the switch 4422 to be turned off, and the filter 441 performs the filtering process on the pixel signal of the preset area. The equalizer 44 transmits the pixel signal after the equalization processing to the digital processing module 45, and the digital processing module 45 transmits the digital signal to the main control chip through the interface 46 after the processing. After the main control chip executes mosaic processing, denoising and other image processing, the image is displayed on a display.

If the pixel signal is a voltage signal, as shown in fig. 8, fig. 8 is a schematic structural diagram of another image sensor according to an embodiment of the present application. The readout circuit 42 may comprise a second electronic voltage converter 423 and the image sensor 40 may further comprise a second analog-to-digital converter 47, wherein an input of the second analog-to-digital converter 47 is coupled to an output of the equalizer 44.

Specifically, the pixel array 41 may convert the received optical signal into an electrical signal, and the electrical signal may be converted into a voltage signal by the second electronic voltage converter 423 and store the voltage signal to the memory 43. The equalizer 44 reads the pixel signal of the preset area from the memory 43, and if the average intensity value represented by the voltage signal in the preset area is greater than the preset threshold value, the trigger 4421 triggers the switch 4422 to be turned off, and the filter 441 performs the filtering process on the pixel signal of the preset area. The equalizer 44 transmits the pixel signal after the equalization process to the second analog-to-digital converter 47, the second analog-to-digital converter 47 converts the voltage signal into a digital signal, and transmits the digital signal to the digital processing module 45, and the digital processing module 45 transmits the digital signal to the main control chip through the interface 46 after processing. After the main control chip executes mosaic processing, denoising and other image processing, the image is displayed on a display.

If the pixel signal is a current signal, as shown in fig. 9, fig. 9 is a schematic structural diagram of another image sensor according to an embodiment of the present application. The readout circuitry 42 may include an electronic current converter 424 and the image sensor 40 may further include a current-to-voltage converter 48 and a third analog-to-digital converter 49, with an input of the current-to-voltage converter 48 coupled to an output of the equalizer 44 and an output of the current-to-voltage converter 48 coupled to an input of the third analog-to-digital converter 49. The electronic current converter 424 is configured to convert an electrical signal into a current signal, the current-to-voltage converter 48 is configured to convert the current signal into a voltage signal, and the third analog-to-digital converter 49 is configured to convert the voltage signal into a digital signal.

Specifically, the pixel array 41 may convert the received optical signal into an electrical signal, and the electrical signal may be converted into a current signal by the electronic current converter 424 and store the current signal to the memory 43. The equalizer 44 reads the pixel signal of the preset area from the memory 43, and if the average intensity value represented by the voltage signal in the preset area is greater than the preset threshold value, the trigger 4421 triggers the switch 4422 to be turned off, and the filter 441 performs the filtering process on the pixel signal of the preset area. The equalizer 44 transmits the pixel signal after the equalization process to the current-to-voltage converter 48, the current-to-voltage converter 48 converts the current signal into a voltage signal and transmits the voltage signal to the third analog-to-digital converter 49, the third analog-to-digital converter 49 converts the voltage signal into a digital signal and transmits the digital signal to the digital processing module 45, and the digital processing module 45 processes the digital signal and transmits the digital signal to the main control chip through the interface 46. After the main control chip executes mosaic processing, denoising and other image processing, the image is displayed on a display.

The method for operating the image sensor provided in the embodiments of the present application is described below as applied to the image sensor mentioned above. As shown in fig. 10, fig. 10 is a flowchart of an operation method of an image sensor according to an embodiment of the present application. The method comprises the following steps:

s1001, the image sensor controls the pixel array to convert the received optical signal into an electrical signal.

Illustratively, a light sensing device in a pixel array may convert a received light signal into an electrical signal. In addition, the pixel array may be of a different type, such as an RGB array, an RGBW array, an RGGB array, or a RYYB array. The specific implementation of S1001 may be referred to the above description of the pixel array, and will not be repeated here.

S1002, the image sensor control readout circuit converts the electrical signal into a pixel signal. The pixel signals are used for representing the intensity values of the pixel points of the pixel array.

The pixel signal may be in the form of a digital signal or an analog signal, for example, if the pixel signal is a digital signal, the subsequent filter is a digital filter, and if the pixel signal is an analog signal, the subsequent filter is an analog filter. The specific implementation of S1002 may be referred to the above description of the readout circuit, and will not be repeated here.

S1003, the image sensor control memory stores the pixel signal.

The memory may be, for example, a buffer for temporarily storing pixel signals from the readout circuit. The specific implementation of S1003 may refer to the above description of the memory, and will not be repeated here.

S1004, the image sensor control filter reads the pixel signals from the memory, and performs equalization processing on the pixel signals. The difference between the intensity value of the pixel signal after the equalization processing and the intensity value of the adjacent pixel signal is smaller than a preset value.

Illustratively, the filter equalizes the pixel signals to reduce the intensity value of the high frequency imbalance signal in the pixel signals to equalize the pixel signals. The specific implementation of S1004 may be referred to the above description of the equalizer, and will not be repeated here.

Optionally, the method may further include: the image sensor controls the weight matcher to match different weights according to the intensity values of different pixel points. S1004 may include: the image sensor controls the filter to read the pixel signals from the memory, and the pixel signals are subjected to different degrees of filtering processing by the more different weights so as to realize pixel signal equalization.

Optionally, S1004 may further include: the image sensor control filter reads pixel signals of the pixels of the preset area from the memory, and when the pixel signals of the pixels of the preset area are larger than a preset threshold value, the pixel signals of the pixels of the preset area are subjected to equalization processing based on the first weight. Or when the pixel signals of the pixels in the preset area are smaller than or equal to the preset threshold value, the image sensor controls the equalizer to perform filtering processing on the pixel signals of the pixels in the preset area based on the second weight, and the first weight is larger than the second weight.

Optionally, S1004 may further include: when the pixel signals of the pixels in the preset area are larger than a preset threshold value, the control switch is turned off to control the filter to perform filtering processing on the pixel signals of the pixels in the preset area based on the first weight. Or when the pixel signals of the pixel points in the preset area are smaller than or equal to the preset threshold value, the control switch is turned on to control the filter to perform filtering processing on the pixel signals of the pixel points in the preset area based on the second weight.

Optionally, S1004 may further include: the image sensor control filter obtains the number of each pixel point of the pixel array in the preset area. And controlling the filter to carry out filtering processing on the pixel signals of each pixel point based on the filtering proportion, wherein the filtering proportion is stored in the page table.

Optionally, when the pixel signal is a digital signal, the method may further include: the image sensor controls the first electronic voltage converter to convert the electrical signal into an analog signal. And the image sensor controls the first analog-to-digital converter to convert the analog signal into a digital signal.

Optionally, when the pixel signal is a voltage signal, S1002 may include: the electronic voltage converter is controlled to convert the electrical signal into a voltage signal. The method may further comprise: the image sensor controls the second analog-to-digital converter to convert the pixel signal into a digital signal.

Optionally, when the pixel signal is a current signal, S1002 may include: the electronic current converter is controlled to convert the electrical signal into a current signal. The method may further comprise: the current-to-voltage converter is controlled to convert the current signal into a voltage signal. And controlling the third analog-to-digital converter to convert the voltage signal into a digital signal.

In summary, as shown in fig. 11, fig. 11 is a comparison chart of an image according to an embodiment of the present application. In some scenes, such as a gray plate, still scene, or monochrome scene, where (a) in fig. 11 is an image output by an image sensor that does not include an equalizer, and (b) in fig. 11 is an image output by an image sensor that includes an equalizer. As can be seen from fig. 11, when the pixel signals are subjected to the equalization processing using the image sensor including the equalizer, the occurrence of streaks in the image sensor is greatly improved.

As shown in fig. 12, fig. 12 is a schematic structural diagram of a graphics processing apparatus according to an embodiment of the present application. The graphics processing apparatus 1200 may include a lens 1201, an image sensor 40, and a processor 1202. The lens 1201 is used to receive the optical signal, and the processor 1202 may process the pixel signal transmitted by the image sensor 40.

Embodiments of the present application also provide an electronic device including one or more processors and one or more memories. The one or more memories are coupled to the one or more processors, the one or more memories being operable to store computer program code comprising computer instructions that, when executed by the one or more processors, cause the electronic device to perform the related method steps described above to implement the method of operating an image sensor in the embodiments described above.

Embodiments of the present application also provide a computer storage medium having stored therein computer instructions which, when executed on an electronic device, cause the electronic device to perform the above-described related method steps to implement the method of operating an image sensor in the above-described embodiments.

Embodiments of the present application also provide a computer program product, which when run on a computer, causes the computer to perform the above-mentioned related steps to implement the method of operating an image sensor performed by the electronic device in the above-mentioned embodiments.

In addition, embodiments of the present application also provide an apparatus, which may be specifically a chip, a component, or a module, and may include a processor and a memory connected to each other; the memory is configured to store computer-executable instructions, and when the apparatus is running, the processor may execute the computer-executable instructions stored in the memory, so that the chip executes the operation method of the image sensor executed by the electronic device in each method embodiment.

The electronic device, the computer storage medium, the computer program product, or the chip provided in this embodiment are used to execute the corresponding methods provided above, so that the beneficial effects thereof can be referred to the beneficial effects in the corresponding methods provided above, and will not be described herein.

It will be appreciated by those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional modules is illustrated, and in practical application, the above-described functional allocation may be performed by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to perform all or part of the functions described above.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the modules or units is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another apparatus, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and the parts displayed as units may be one physical unit or a plurality of physical units, may be located in one place, or may be distributed in a plurality of different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions for causing a device (may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read Only Memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An image sensor, comprising: a pixel array, a readout circuit, a memory, and an equalizer;

the output end of the pixel array is coupled with the input end of the reading circuit, the output end of the reading circuit is coupled with the memory, and the memory is also coupled with the input end of the equalizer;

the pixel array is used for converting the received optical signals into electric signals;

the readout circuit is used for converting the electric signals into pixel signals, and the pixel signals are used for representing the intensity values of the pixel points of the pixel array;

the memory is used for storing the pixel signals;

the equalizer comprises a filter, wherein the filter is used for reading the pixel signals from the memory and performing equalization processing on the pixel signals, and the difference value between the intensity value of the pixel signals after the equalization processing and the intensity value of the adjacent pixel signals is smaller than a preset value.

2. The image sensor of claim 1, wherein the equalizer further comprises a weight matcher, an output of the weight matcher coupled to an input of the filter;

the weight matcher is used for matching different weights according to the intensity values of different pixel points;

The filter is specifically configured to read the pixel signal from the memory, and perform filtering processing on the pixel signal to different degrees according to different weights, so as to achieve the pixel signal equalization.

3. The image sensor according to claim 2, wherein the filter is specifically configured to read a pixel signal of a pixel of a preset area from the memory, and perform a filtering process on the pixel signal of the pixel of the preset area based on a first weight when the pixel signal of the pixel of the preset area is greater than a preset threshold.

4. The image sensor of claim 3, wherein the filter is further specifically configured to perform a filtering process on the pixel signal of the pixel point of the preset area based on a second weight when the pixel signal of the pixel point of the preset area is less than or equal to the preset threshold, where the first weight is greater than the second weight.

5. The image sensor of claim 4, wherein the weight matcher includes a trigger and a switch; the input end of the trigger is coupled with the input end of the equalizer, the output end of the trigger is coupled with the control end of the switch, the first end of the switch is coupled with the input end of the equalizer, the second end of the switch is coupled with the output end of the equalizer, the first end of the filter is coupled with the input end of the equalizer, and the second end of the filter is coupled with the output end of the equalizer;

The trigger is used for controlling the switch to be disconnected when the pixel signal of the pixel point of the preset area is larger than the preset threshold value;

the trigger is further configured to control the switch to be turned on when the pixel signal of the pixel point in the preset area is less than or equal to the preset threshold;

and the filter is used for carrying out filtering processing on the pixel signals of the pixel points of the preset area based on the first weight when the switch is disconnected.

6. The image sensor of claim 5, wherein the pixel array comprises at least three pixel points, and the filter is specifically configured to obtain the number of each pixel point in the preset area; and filtering the pixel signals of each pixel point based on a filtering proportion, wherein the filtering proportion is stored in a page table.

7. The image sensor of claim 1, wherein the preset value is related to an intensity value at which the pixel signal is calibrated.

8. The image sensor of any one of claims 1-7, wherein when the pixel signal is a digital signal, the readout circuit comprises: a first electronic voltage converter and a first analog-to-digital converter;

The first electronic voltage converter is used for converting the electric signal into an analog signal;

the first analog-to-digital converter is used for converting the analog signal into the digital signal.

9. The image sensor of any one of claims 1-7, wherein when the pixel signal is a voltage signal, the readout circuit comprises: a second electronic voltage converter, the image sensor further comprising: a second analog-to-digital converter, an input of the second analog-to-digital converter being coupled to an output of the equalizer;

the electronic voltage converter is used for converting the electric signal into the voltage signal;

the second analog-to-digital converter is used for converting the pixel signals into digital signals.

10. The image sensor of any one of claims 1-7, wherein when the pixel signal is a current signal, the readout circuit comprises: an electronic current converter, the image sensor further comprising: a current-to-voltage converter and a third analog-to-digital converter, the input of the current-to-voltage converter being coupled to the output of the equalizer, the output of the current-to-voltage converter being coupled to the input of the third analog-to-digital converter;

The electronic current converter is used for converting the electric signal into the current signal;

the current-voltage converter is used for converting the current signal into a voltage signal;

the third analog-to-digital converter is used for converting the voltage signal into a digital signal.

11. A method of operating an image sensor, the image sensor comprising an array of pixels, a readout circuit, a memory, and an equalizer, an output of the array of pixels being coupled to an input of the readout circuit, an output of the readout circuit being coupled to the memory, the memory also being coupled to an input of the equalizer, the equalizer comprising a filter; the method comprises the following steps:

controlling the pixel array to convert the received optical signal into an electrical signal;

controlling the readout circuit to convert the electrical signal into a pixel signal, wherein the pixel signal is used for representing the intensity value of a pixel point of the pixel array;

controlling the memory to store the pixel signals;

and controlling the filter to read the pixel signals from the memory, and carrying out equalization processing on the pixel signals, wherein the difference value between the intensity value of the pixel signals after the equalization processing and the intensity value of the adjacent pixel signals is smaller than a preset value.

12. The method of claim 11, wherein the equalizer further comprises a weight matcher, an output of the weight matcher coupled to an input of the filter, the method further comprising:

controlling the weight matcher to match different weights according to the intensity values of different pixel points;

the controlling the filter to read the pixel signal from the memory and perform equalization processing on the pixel signal includes:

and controlling the filter to read the pixel signals from the memory, and carrying out filtering processing on the pixel signals to different degrees according to different weights so as to realize the pixel signal equalization.

13. The method of claim 12, wherein controlling the filter to read the pixel signal from the memory and to filter the pixel signal to different extents according to different weights comprises:

and controlling the filter to read the pixel signals of the pixel points of the preset area from the memory, and carrying out equalization processing on the pixel signals of the pixel points of the preset area based on a first weight when the pixel signals of the pixel points of the preset area are larger than a preset threshold value.

14. The method of claim 13, wherein the controlling the filter to read the pixel signal from the memory and to filter the pixel signal to different extents according to different weights, further comprises:

and controlling the equalizer to perform filtering processing on the pixel signals of the pixel points of the preset area based on a second weight when the pixel signals of the pixel points of the preset area are smaller than or equal to the preset threshold, wherein the first weight is larger than the second weight.

15. The method of claim 14, wherein the weight matcher includes a trigger and a switch; the input end of the trigger is coupled with the input end of the equalizer, the output end of the trigger is coupled with the control end of the switch, the first end of the switch is coupled with the input end of the equalizer, the second end of the switch is coupled with the output end of the equalizer, the first end of the filter is coupled with the input end of the equalizer, and the second end of the filter is coupled with the output end of the equalizer; the controlling the filter to read the pixel signal of the pixel point of the preset area from the memory, and when the pixel signal of the pixel point of the preset area is greater than a preset threshold, performing filtering processing on the pixel signal of the pixel point of the preset area based on a first weight includes:

When the pixel signal of the pixel point of the preset area is larger than the preset threshold value, the trigger is controlled to be turned off, and the filter is controlled to perform filtering processing on the pixel signal of the pixel point of the preset area based on the first weight;

the controlling the filter to perform filtering processing on the pixel signal of the pixel point of the preset area based on the second weight when the pixel signal of the pixel point of the preset area is less than or equal to the preset threshold value includes:

and controlling the trigger to be conducted when the pixel signal of the pixel point of the preset area is smaller than or equal to the preset threshold value, so as to control the filter to carry out filtering processing on the pixel signal of the pixel point of the preset area based on the second weight.

16. The method of claim 15, wherein the pixel array includes at least three pixel points, and the controlling the filter to perform the equalizing process on the pixel signals of the pixel points of the preset area includes:

controlling the filter to acquire the number of each pixel point of the pixel array in the preset area;

And controlling the filter to carry out filtering processing on the pixel signals of each pixel point based on a filtering proportion, wherein the filtering proportion is stored in a page table.

17. The method of claim 16, wherein the predetermined value is related to an intensity value at which the pixel signal is calibrated.

18. The method according to any one of claims 11-17, wherein when the pixel signal is a digital signal, the readout circuit comprises: a first electronic voltage converter and a first analog-to-digital converter; the controlling the readout circuit to convert the electrical signal into a pixel signal includes:

controlling the first electronic voltage converter to convert the electrical signal into an analog signal;

the first analog-to-digital converter is controlled to convert the analog signal into a digital signal.

19. A method according to any one of claims 11-17, wherein the readout circuitry comprises, when the pixel signal is a voltage signal: a second electronic voltage converter, the image sensor further comprising: a second analog-to-digital converter, an input of the second analog-to-digital converter being coupled to an output of the equalizer; the controlling the readout circuit to convert the electrical signal into a pixel signal includes:

Controlling the electronic voltage converter to convert the electric signal into a voltage signal;

the method further comprises the steps of:

the second analog-to-digital converter is controlled to convert the pixel signal into a digital signal.

20. The method according to any one of claims 11-17, wherein when the pixel signal is a current signal, the readout circuit comprises: an electronic current converter, the image sensor further comprising: a current-to-voltage converter and a third analog-to-digital converter, the input of the current-to-voltage converter being coupled to the output of the equalizer, the output of the current-to-voltage converter being coupled to the input of the third analog-to-digital converter; the controlling the readout circuit to convert the electrical signal into a pixel signal includes:

controlling the electronic current converter to convert the electrical signal into the current signal;

the method further comprises the steps of:

controlling the current-to-voltage converter to convert the current signal into a voltage signal;

the third analog-to-digital converter is controlled to convert the voltage signal into a digital signal.

21. A graphics processing apparatus, comprising:

a lens for receiving the optical signal;

The image sensor of any one of claims 1 to 10;

and the processor is used for processing the pixel signals output by the image sensor.

22. A computer readable storage medium comprising computer instructions which, when run on an electronic device, cause the electronic device to perform the method of any of the preceding claims 11-20.