WO2019104508A1

WO2019104508A1 - Image sensor, chip, image processing device, and related method

Info

Publication number: WO2019104508A1
Application number: PCT/CN2017/113488
Authority: WO
Inventors: 曹子晟
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2017-11-29
Filing date: 2017-11-29
Publication date: 2019-06-06
Also published as: CN108886592A

Abstract

Provided are an image sensor, a chip, an image processing device, and a related method, said image sensor comprising: a pixel array, including a plurality of pixels arranged in a two-dimensional matrix; a first control circuit connected to some pixels in the pixel array, the first control circuit being configured to perform, during the movement of a motor lens, multiple exposures on at least a certain number of said some pixels; a first readout circuit, connected to said some pixels, the first readout circuit being configured to read out first image data after each exposure of at least a certain number of said some pixels; and a processing circuit connected to the first readout circuit, the processing circuit being configured to perform contrast ratio analysis on a plurality of pieces of first image data read out by the first readout circuit, so as to determine a focusing position. Compared with reading image data after exposure of the whole pixel array, the present invention enables the first image data to be read at a higher speed, accordingly allowing the subsequent data processing to be performed faster, thus improving the focusing speed.

Description

Image sensor, chip, image processing device and related method

Copyright statement

The disclosure of this patent document contains material that is subject to copyright protection. This copyright is the property of the copyright holder. The copyright owner has no objection to the reproduction of the patent document or the patent disclosure in the official records and files of the Patent and Trademark Office.

Technical field

The present application relates to the field of data processing and, more particularly, to an image sensor, a chip, an image processing device, and related methods.

Background technique

Currently, autofocus technology is mainly divided into contrast detection (contrast) autofocus technology and phase detection auto focus (PDAF) technology.

Contrast detection Autofocus technology uses autofocus to detect contrast. The specific process is: changing the focal length by driving the motor lens along the axis of the lens, thereby detecting the position of the motor lens when the contrast of the shooting picture is maximum, that is, the accurate focus position, which is also called the focus position. The specific focusing process of contrast detection autofocus technology is as follows: As the motor lens starts to move, the frame of each frame is gradually clear, that is, the contrast starts to rise. When the shooting picture reaches the clearest, that is, the contrast reaches the maximum value, the camera does not know this time. It has reached the best, and will continue to drive the motor lens. The shooting picture begins to blur, that is, the contrast begins to drop. When the camera finds that the contrast starts to drop further, knowing that the focus point (ie, the focus) has been missed, and starting to reverse drive the motor lens, In this way, the loop is gradually approaching the focus position, and after the focus position is found, the focusing process is completed. When the focus process is completed, when the shutter signal is received, shooting is completed and finally output to the camera's display. In the process of contrast detection autofocus technology, it is necessary to move the lens multiple times to find the correct focus position (ie, the focus position), which will take multiple frames of exposure time to achieve focus, resulting in slower focus and affecting the user experience. .

The focusing process of the PDAF technology is roughly as follows: some pixel shading points are reserved in the pixel portion of the image sensor, and the phase difference generated by the different left and right optical wave information received by the partially obscuring point pixels is judged at different in-focus positions, so that The current phase difference calculates the focus position and then quickly moves the lens to the focus position. The PDAF technology improves focus speed compared to contrast detection autofocus technology. However, the PDAF technology is lower than the contrast detection autofocus technology. The accuracy of focusing. It can be seen that the existing autofocus technology cannot balance the focus speed and focus accuracy.

With the development of smart terminals, users are increasingly demanding focus speed and focus accuracy when using the camera function or camera function of the smart terminal. Therefore, it is urgent to provide an auto focus that can better meet user needs. technology.

Summary of the invention

The present application provides an image sensor, a chip, an image processing device, and related methods, which make it possible to achieve both focus speed and focus accuracy.

In a first aspect, an image sensor is provided, the image sensor comprising: a pixel array comprising a plurality of pixels arranged in a two-dimensional matrix, the pixels being light-sensing pixels; a first control circuit, and the pixel array Partially connected to the pixel, the first control circuit is configured to perform multiple exposures on at least a part of the pixels in the moving process of the motor lens; and the first readout circuit is connected to the partial pixel, the first a readout circuit for reading out first image data after each exposure of at least a portion of the pixels of the partial pixels; processing circuitry coupled to the first readout circuitry, the processing circuitry for The plurality of first image data read by the first readout circuit performs contrast analysis to determine a focus position.

The image sensor provided by the present application focuses only on the first image data read out after partial pixel exposure in the pixel array during the focusing process. It should be understood that the smaller the data, the faster the data readout speed. Therefore, the readout speed of the first image data is faster than the image data read out after exposure based on the entire pixel array, and accordingly, the subsequent data processing is also faster, so that the focus speed can be improved. In addition, the image sensor provided by the present application, like the existing contrast detection autofocus technology, realizes autofocus by detecting the contrast of the photographed screen, and can ensure the accuracy of the focus to a certain extent. Therefore, the image sensor provided by the present application makes it possible to achieve both focus speed and focus accuracy.

With reference to the first aspect, in a possible implementation manner of the first aspect, the image sensor further includes: a second control circuit, connected to all pixels in the pixel array, the second control circuit is configured to The pixels are subjected to at least one exposure, wherein the performing at least one exposure on the pixels includes exposing the pixels at the focus position; and the second readout circuit is coupled to the pixels The first readout circuit is configured to read out second image data after each exposure of the pixels; the processing circuit is further connected to the second readout circuit, The processing circuit is further configured to obtain an output image according to the second image data read by the second readout circuit after the pixels are exposed at the focus position.

The image sensor provided by the present application achieves focusing by utilizing a part of pixels in the pixel array instead of focusing on the entire pixel array in the existing contrast detection autofocus technology, thereby improving the focusing speed. In addition, the image sensor provided by the present application, like the existing contrast detection autofocus technology, realizes autofocus by detecting the contrast of the photographed screen, and can ensure the accuracy of the focus to a certain extent. Therefore, the image sensor provided by the present application makes it possible to achieve both focus speed and focus accuracy.

It should be noted that the first control circuit and the second control circuit are designed independently of each other, and the first readout circuit and the second readout circuit are designed independently of each other. The connection relationship between the entire pixel array and the second control circuit and the second readout circuit in the image sensor provided by the present application may be similar to the connection relationship between the pixel array and the control circuit and the readout circuit in the existing image sensor. It can even be the same. Therefore, the image sensor provided by the present application does not add a large design complexity to the existing image sensor.

With reference to the first aspect, in a possible implementation manner of the first aspect, the first control circuit is configured to perform exposure on at least a part of the partial pixels according to a first frame rate, where the second The control circuit is specifically configured to expose the pixels according to a second frame rate, wherein the first frame rate is higher than the second frame rate.

In conjunction with the first aspect, in a possible implementation manner of the first aspect, the first frame rate is n times the second frame rate, and n is an integer greater than 1.

In the image sensor provided by the present application, the frame rate of the image data for focusing is higher than the frame rate of the image data for presenting the captured image. In the existing contrast detection autofocus technique, the frame rate of image data for focusing is the same as the frame rate of image data for presenting a captured image. Therefore, compared with the prior art, the image sensor provided by the present application can effectively improve the focusing speed. Since the present application still presents the captured image based on the entire pixel array, the image quality of the captured image is not lowered.

In a second aspect, a chip is provided, the chip comprising the image sensor provided by the first aspect.

In a third aspect, an image processing apparatus is provided, the image processing apparatus comprising the image sensor provided by the first aspect.

In a fourth aspect, a method for controlling an image sensor, the image sensor comprising a pixel array, the pixel array comprising a plurality of pixels arranged in a two-dimensional matrix, the pixels being light sense In response to pixels, the method includes: performing multiple exposures on at least a portion of the pixels in the pixel array during movement of the motor lens; reading at least a portion of the pixels in the partial pixels after each exposure First image data; performing contrast analysis on the read plurality of first image data to determine a focus position of the image sensor.

With reference to the fourth aspect, in a possible implementation manner of the fourth aspect, the method further includes: performing multiple exposures on all pixels in the pixel array, wherein the performing the plurality of pixels multiple times Exposing includes exposing all of the pixels at the focus position; reading second image data after each exposure of the pixels; reading after exposure of the pixels at the focus position The second image data is output to obtain an output image.

With reference to the fourth aspect, in a possible implementation manner of the fourth aspect, the performing the multiple exposures on at least a part of the pixels in the pixel array includes: following the first frame rate, At least a portion of the pixels in the plurality of pixels are subjected to multiple exposures; the plurality of pixels in the pixel array being subjected to multiple exposures, including: performing multiple exposures on all pixels in the pixel array according to a second frame rate, The first frame rate is higher than the second frame rate.

In conjunction with the fourth aspect, in a possible implementation manner of the fourth aspect, the first frame rate is n times the second frame rate, and n is an integer greater than 1.

In the image focusing process provided by this embodiment, only the first image data read out after partial pixel exposure in the pixel array is used for focusing. It should be understood that the smaller the data, the faster the data readout speed. Therefore, the readout speed of the first image data is faster than the image data read out after exposure based on the entire pixel array, and accordingly, the subsequent data processing is also faster, so that the focus speed can be improved. In addition, the image sensor provided by the present application, like the existing contrast detection autofocus technology, realizes autofocus by detecting the contrast of the photographed screen, and can ensure the accuracy of the focus to a certain extent. Therefore, the image sensor provided by the present application makes it possible to achieve both focus speed and focus accuracy.

DRAWINGS

FIG. 1 is a schematic block diagram of an image sensor according to an embodiment of the present application.

FIG. 2 is another schematic block diagram of an image sensor according to an embodiment of the present application.

FIG. 3 is a schematic diagram of pixel exposure of an image sensor according to an embodiment of the present application.

FIG. 4 is a diagram showing an example of an image sensor according to an embodiment of the present application.

FIG. 5 is a schematic block diagram of a chip according to an embodiment of the present application.

FIG. 6 is a schematic block diagram of an image processing device according to an embodiment of the present application.

FIG. 7 is a schematic flowchart of a method for controlling an image sensor according to an embodiment of the present application.

FIG. 8 is another schematic flowchart of a method for controlling an image sensor according to an embodiment of the present application.

Detailed ways

For the sake of understanding, the principle of imaging the camera or camera is briefly introduced.

The process of capturing images from the camera to presenting a user-visible photographing screen on the display screen is as follows: the camera photographing screen; the camera photographing screen generates an optical image through its lens; the optical image is projected onto the image sensor, and the optical image is converted into an image sensor by the image sensor The electrical signal is converted into a digital signal output through the readout circuit; the digital signal is finally outputted to the display screen of the terminal through digital signal processing (DSP), and becomes a photographing picture that the user can see.

In the above process, an optical image is converted from an optical signal into an electrical signal by an image sensor. An image array consisting of light-sensitive pixels is included in the image sensor. These light-sensing pixels can convert optical signals into electrical signals. The basic conversion process of an image sensor for converting an optical image from an optical signal to an electrical signal is as follows: exposing the pixel array in the image sensor, the pixels in the pixel array will generate voltage with different light intensities within a certain exposure time, subsequent The readout circuit converts this voltage into a digital signal output. Among them, the exposure time mainly refers to the photosensitive time of the film, and the longer the exposure time, the brighter the photo generated on the film, and the darker the opposite.

FIG. 1 is a schematic block diagram of an image sensor 100 according to an embodiment of the present disclosure. The image sensor 100 includes a pixel array 110, a first control circuit 120, a first readout circuit 130, and a processing circuit 140.

The pixel array 110 includes a plurality of pixels arranged in a two-dimensional matrix, the pixels being light-sensing pixels.

Specifically, the pixel array is as shown in FIG.

The first control circuit 120 is connected to a part of pixels in the pixel array 110, and the first control circuit 120 is configured to perform multiple exposures on at least a part of the pixels in the moving process of the motor lens, wherein the The motor lens can be a lens of at least one of the lenses that can be moved through the lens controlled by the step motor.

Specifically, the first control circuit 120 is connected to each of the partial pixels.

It should be noted that although the first control circuit 120 is connected to each pixel in the partial pixel, it is not necessarily controlled to expose each pixel in the partial pixel, and in practical applications, flexible control can be performed.

Optionally, the first control circuit 120 is configured to perform multiple exposures for each of the partial pixels during the movement of the motor lens.

Optionally, the first control circuit 120 is configured to perform multiple exposures on a part of the pixels in the partial pixels during the movement of the motor lens.

It should be understood that during focusing, the motor lens will be driven to move along the axis of the lens.

It should be understood that the first control circuit 120 and the first readout circuit 130 are circuits connected to all of the pixels, which are connected to a part of the pixels, which may be two circuits, may be one circuit, or may be multiple Circuit composition, here is just a classification using functions.

The first readout circuit 130 is connected to the partial readout circuit 130, and the first readout circuit 130 is configured to read the first image data after each exposure of at least a part of the pixels in the partial pixels.

Specifically, the first readout circuit 130 is connected to each of the partial pixels.

Optionally, in a case where the first control circuit 120 performs multiple exposures on each of the partial pixels, the first image data is read by the first readout circuit 130 after all the pixels in the partial pixels are exposed. Out of the image data.

Optionally, in a case where the first control circuit 120 performs a plurality of exposures on a part of the pixels in the partial pixels, the first image data is read by the first readout circuit 130 after a part of the pixels in the partial pixels are exposed. Image data.

The processing circuit 140 is connected to the first readout circuit 130, and the processing circuit 140 is configured to perform contrast analysis on the plurality of first image data read by the first readout circuit 130 to determine a focus position.

It should be understood that the processing circuit 140 is also coupled to a drive circuit for driving the motor lens.

Specifically, the process of determining the focus position by the processing circuit 140 is as follows: as the motor lens starts to move, the processing circuit 140 detects that the contrast of each frame captured by the first readout circuit 130 starts to rise, that is, the captured image gradually becomes clear. In this process, the processing circuit 140 can instruct the driving circuit to continue to drive the motor lens movement along the original direction; when the processing circuit 140 detects that the contrast of each frame of the captured image read by the first reading circuit 130 begins to decrease, that is, the shooting screen When gradually blurred, the processing circuit 140 can instruct the driving circuit to start in the opposite direction (relative to a moment on the motor lens) In terms of moving direction, the driving motor lens moves, and then continues to detect the contrast of each frame of the image read by the first reading circuit 130. As long as the contrast is detected to start to decrease, the motor lens is driven in the opposite direction, so that the motor lens can be continuously circulated. Gradually close to the focus position. Of course, the time threshold or the lens shift threshold can be set when the contrast begins to drop. For example, if the contrast is always falling within a time threshold or a lens shift threshold, the processing circuit 140 can instruct the driving circuit to start driving the motor lens in the opposite direction. If the contrast first drops and then rises, the processing circuit 140 can drive the motor lens according to the The original direction continues to move to find a better focus position, which is not limited here.

The focus position is a position of the motor lens corresponding to a first image data of which the contrast is optimal among the plurality of first image data.

In the image focusing process provided by this embodiment, only the first image data read out after partial pixel exposure in the pixel array is used for focusing. It should be understood that the smaller the number of pixels read by the first readout circuit 130, the less the data, and the less time the data read speed is, the less time is consumed. Therefore, the readout speed of the first image data is faster than the image data read out after exposure based on the entire pixel array, and accordingly, the subsequent data processing is also faster, so that the focus speed can be improved. In addition, the image sensor provided by the present application, like the existing contrast detection autofocus technology, realizes autofocus by detecting the contrast of the photographed screen, and can ensure the accuracy of the focus to a certain extent. Therefore, the image sensor provided by the present application makes it possible to achieve both focus speed and focus accuracy.

It should be noted that, while partial pixels are exposed under the control of the first control circuit 120 for autofocusing, the entire pixel array is also in normal exposure operation, and the image data read out after exposure is used to present the image to the user. image.

As shown in FIG. 2, the image sensor 100 further includes a second control circuit 150 and a second readout circuit 160.

The second control circuit 150 is connected to all the pixels in the pixel array 110, and the second control circuit 150 is configured to perform at least one exposure on all the pixels, wherein the at least one exposure of the pixels is included in the The focal position exposes all of the pixels.

Specifically, the second control circuit 150 is connected to each pixel in the pixel array 110.

Optionally, the second control circuit 150 performs at least one exposure on all pixels in the pixel array 110, meaning that the second control circuit 150 exposes the pixel array 110 when the motor lens is in the focus position.

Optionally, the second control circuit 150 performs at least one exposure on all the pixels in the pixel array 110, that is, the second control circuit 150 performs multiple exposures on the pixel array 110 during the movement of the motor lens, and the multiple times The exposure process includes exposure of the second control circuit 150 to the pixel array 110 when the motor lens is in the focus position.

The second readout circuit 160 is connected to all the pixels, and the first readout circuit 160 is configured to read the second image data after each exposure of all the pixels.

Specifically, the second readout circuit 160 is connected to each pixel in the pixel array 110.

The second readout circuit 160 reads the second image data once for each exposure of the pixel array 110.

For example, the second image data read by the second readout circuit 160 can be finally presented on the display screen of the terminal device by the DSP for the user to preview or the final photo.

The processing circuit 140 is further connected to the second readout circuit 160. The processing circuit 140 is further configured to: according to the second readout circuit, the second image read after the all pixels are exposed at the focus position Data, get the output image.

Specifically, the processing circuit 140 is configured to output the image data read out at the focus position in the plurality of second image data read out by the second readout circuit 160, for example, displayed on a display screen for the user to browse. Or output image data read out including the exposure at the focus position to form a final image.

It should be understood that when the user uses the camera or other imaging device, the final shooting picture is obtained when the shutter is pressed. Usually, when the user finishes focusing, for example, when the screen is clear, the shutter is pressed when the screen is clear, that is, the shutter is pressed after the focus is over.

Specifically, in this embodiment, the second control circuit 160 is configured to expose all the pixels at the focus position when the shutter signal is received.

The processing circuit 140 is further configured to obtain the output image according to the second image data read by the second readout circuit 160 after the exposure of all the pixels based on the shutter signal, when the shutter signal is received.

It should be understood that the second control circuit 150 and the second readout circuit 160 are circuits connected to all the pixels, which may be two circuits, or may be one circuit, or may be composed of multiple circuits, and only use functions. The classification.

The image sensor provided by the present application can achieve focusing by utilizing a part of pixels in the pixel array, thereby improving the focusing speed. In addition, autofocus is achieved by detecting the contrast of the captured image. The accuracy of the focus can be guaranteed to a certain extent. Therefore, the image sensor provided by the present application makes it possible to achieve both focus speed and focus accuracy.

Optionally, in some embodiments, the first control circuit 120 is configured to perform exposure on at least a portion of the pixels in the first frame rate, where the second control circuit 150 is specifically configured to follow The two frame rates are exposed to all of the pixels, wherein the first frame rate is higher than the second frame rate.

Specifically, the frame rate of the first image data read by the first readout circuit is higher than the frame rate of the second image data read by the second readout circuit. In other words, the frame rate of the image data for focusing is higher than the frame rate of the image data for presenting the captured image. In the existing contrast detection autofocus technique, the frame rate of image data for focusing is the same as the frame rate of image data for presenting a captured image. Therefore, compared with the prior art, the image sensor provided by the present application can effectively improve the focusing speed. Since the present application still presents the captured image based on the entire pixel array, the image quality of the captured image is not lowered.

Optionally, as an example, the first frame rate is n times the second frame rate, and n is an integer greater than 1.

The frame data corresponding to the first image data is recorded as an automatic focus (AF) frame, and the frame data corresponding to the second image data is recorded as a normal frame. The reading speed of the AF frame and the normal frame is as shown in FIG. The read time of an AF frame is T1, T1 = 1/M' seconds, and the read time of a normal frame is T2, T2 = 1/M, M = M' / n, and n is a positive integer. That is, the AF frame is read at a speed n times with respect to the normal frame.

In the present embodiment, the processing circuit 140 determines the focus position by performing contrast analysis on the AF frame. The read speed of the AF frame is n times the reading speed of the normal frame, so that the focus speed can be improved by n times compared with the conventional contrast detection autofocus technology. In addition, as can be seen from FIG. 3, the exposure node of the normal frame and the AF frame coincide, which improves the utilization of the pixel array.

In this embodiment, since the frame rate of the AF frame is n times the frame rate of the normal frame, therefore, the pair thereof The exposure time of the pixel should be relatively short, but the peripheral pixel value and frame rate can be used for compensation calculation in the later stage to achieve the minimum image quality.

FIG. 4 shows an exemplary diagram of an image sensor provided by an embodiment of the present application. The image sensor includes a pixel array (Pixel Array), and the pixel array includes pixels arranged in a rectangular array. Some of the pixels in the pixel array act as autofocus pixels. These autofocus pixels are connected to the autofocus line control circuit and to the autofocus column readout circuitry. During the movement of the motor lens, the autofocus line control circuit is used to control the autofocus pixels for multiple exposures; the autofocus column readout circuit is used to read the corresponding first image data after the autofocus pixels are exposed. Each pixel in the entire pixel array is connected to a normal exposure line control circuit and also to a normal exposure column readout circuit. The normal exposure line control circuit is configured to control the pixel array to perform multiple exposures during the movement of the motor lens, and control the pixel array to perform exposure when the shutter signal is received; the normal exposure column readout circuit is used after the pixel array is exposed The corresponding second image data is read out.

It should be noted that the auto focus line control circuit and the normal exposure line control circuit are designed independently of each other, and the auto focus column readout circuit and the normal exposure column readout circuit are designed independently of each other.

It should be understood that the pixel array in the embodiment shown in FIG. 4 corresponds to the pixel array 110 in the above embodiment, and the auto-focus pixel in the embodiment shown in FIG. 4 corresponds to a part of the pixels in the above embodiment, and is implemented in FIG. The autofocus row control circuit in the example corresponds to the first control circuit in the above embodiment, and the autofocus column readout circuit in the embodiment shown in FIG. 4 corresponds to the first readout circuit in the above embodiment, and FIG. 4 The normal exposure line control circuit in the illustrated embodiment corresponds to the second control circuit in the above embodiment, and the normal exposure column readout circuit in the embodiment shown in Fig. 4 corresponds to the second readout circuit in the above embodiment.

The image sensor shown in FIG. 4 further includes a processing circuit (not shown in FIG. 4) that is coupled to the auto-focus column readout circuit and the normal exposure column readout circuit. Specifically, the processing circuit is configured to perform focusing according to the first image data read by the auto-focus column readout circuit to determine a focus position, so that the motor lens reaches the focus position. The processing circuit is further configured to obtain an output image according to the second image data read by the normal exposure column readout circuit when the shutter signal is received. For example, a shooting picture is presented on the display of the device.

As can be seen from FIG. 4, the image sensor provided by the present application only needs to select a part of pixels from the pixel array and connect the partial pixels to the independent control circuit and the readout circuit for the image sensor. No changes have been made. Therefore, the image sensor provided by the present application has a low design complexity.

It should be understood that FIG. 4 is merely an example and not a limitation. The layout manner of the partial pixels for autofocus in the present application includes, but is not limited to, the layout manner of the AF pixels shown in FIG. In practical applications, some of the pixels used for autofocusing may be randomly distributed, which is not limited in this embodiment of the present application.

Optionally, in some embodiments, the partial pixels include pixels distributed in different rows or different columns of the pixel array.

Specifically, the partial pixels are taken as an example of the auto-focus pixels shown in FIG. 4 , and among the auto-focus pixels, some pixels have different rows, and some pixels have different columns.

Optionally, in some embodiments, the location of the portion of pixels in the array of pixels is preset.

Specifically, the portion of pixels has been selected from the pixel array prior to molding of the pixel array. Correspondingly, the connection relationship between the partial pixels and the first control circuit and the first readout circuit has also been determined.

As described above, although the first control circuit and the first readout circuit are connected to each of the pixels in the portion of the pixels, not every pixel in the portion of the pixels is exposed.

Optionally, in some embodiments, the first control circuit 120 is specifically configured to perform multiple exposures for each of the partial pixels during movement of the motor lens.

Optionally, in some embodiments, the first control circuit 120 is configured to perform, according to the preset information, at least a part of the pixels in the part of the pixels during the movement of the motor lens, the preset information. A distribution location of the at least a portion of the pixels in the portion of pixels is indicated.

Specifically, the preset information may be information pre-configured into the image sensor. For example, for the application scenario 1, the preset information indicates a part of the pixels in the partial layout distributed in the first layout. For the application scenario 2, the preset information indicates a part of the pixels in the partial layout in the second layout.

The image sensor provided in this embodiment can further improve the focusing speed.

Optionally, in some embodiments, the distribution locations of the at least one portion of the pixels in the partial pixels are different in different focus scenes.

Optionally, in some embodiments, the distribution positions of the at least one portion of the pixels in the partial pixels corresponding to the different exposure processes in the same focus scene are not completely the same.

Specifically, in one focusing task, as the motor lens moves, the first control circuit can appropriately change the pixels to be exposed during the process of controlling the partial pixels for exposure.

For example, at different focus times, when the rate of change of contrast is large, less pixels of some pixels are selected for exposure, and when the rate of change of contrast is small, some pixels are selected. Multiple pixels are exposed. For another example, when the user selects the position of the shooting focus (distinguished from the focus in the focus process) when taking the photo, a part of the pixels are selected for exposure in the vicinity of the position on the pixel array corresponding to the shooting focus.

The image sensor provided by the embodiment can improve the focusing speed while improving the focusing flexibility.

Optionally, the image sensor provided by the embodiment of the present application may be a complementary metal oxide semiconductor (CMOS) image sensor.

As shown in FIG. 5, the embodiment of the present application further provides a chip 500, which includes an image sensor 510, which corresponds to the image sensor provided by the above device embodiment.

Specifically, the image sensor provided by the above device embodiment can be inherited on the chip.

Optionally, the chip 500 may further include a processor 520 for processing the image data output by the image sensor 510 into a captured image that can be presented on a display screen.

As shown in FIG. 6 , an embodiment of the present application further provides an image processing device 600. The image processing device 600 includes a processor 610, a display screen 620, and an image sensor 630. The image sensor 630 corresponds to the image sensor provided by the device embodiment. . The processor 610 is configured to process the image data output by the image sensor 630 into a captured image that can be presented on the display screen 630.

Alternatively, the image processing device 600 may be a terminal. The terminal may be a terminal device integrated with a camera and a display, including but not limited to a smartphone, a tablet, a palmtop, a camera, and the like. The camera in the terminal is used for realizing the photographing and photographing functions, and the display screen is used for realizing the preview function of the photographing screen, that is, real-time display of the current income of the camera for previewing, thereby achieving the effect of the viewfinder. .

The method embodiments of the present invention are described below. Since the method embodiments can be performed by the image sensor described in the above apparatus implementation, portions of the apparatus that are not described in detail can be referred to the foregoing apparatus embodiments.

As shown in FIG. 7 , an embodiment of the present application further provides a method for controlling an image sensor, where the image sensor includes a pixel array, and the pixel array includes a plurality of pixels arranged in a two-dimensional matrix, and the method includes:

S710, performing multiple exposures on at least a part of the pixels in the pixel array during movement of the motor lens;

S720, reading at least a part of the pixels in the partial pixel after each exposure;

S730: Perform contrast analysis on the read plurality of first image data to determine a focus position of the image sensor.

Optionally, in some embodiments, the method further includes:

Performing multiple exposures on all pixels in the pixel array, wherein the plurality of exposures to the plurality of pixels includes exposing all of the pixels at the focus position;

Reading the second image data after each exposure of the pixels;

An output image is obtained based on the second image data read after the exposure of all the pixels at the focus position.

Optionally, in some embodiments, performing multiple exposures on all pixels in the pixel array includes: exposing all the pixels at the focus position when receiving the shutter signal;

Obtaining an output image according to the second image data read after the all pixels are exposed at the focus position, comprising: after receiving the shutter signal, according to the exposure of the pixels based on the shutter signal The read second image data obtains the output image.

Optionally, in some embodiments, as shown in FIG. 8, the method specifically includes:

S711: performing multiple exposures on at least a part of the pixels in the partial frame rate during the movement of the motor lens;

S730, performing contrast analysis on the read plurality of first image data to determine a focus position of the image sensor;

S741, performing multiple exposures on all pixels in the pixel array according to a second frame rate, wherein the first frame rate is higher than the second frame rate, and performing multiple exposures on the pixels includes: Positioning all pixels for exposure;

S750, reading the second image data after each exposure of the pixels;

S760, obtaining an output image according to the second image data read after the exposure of all the pixels at the focus position.

Optionally, in some embodiments, the first frame rate is n times the second frame rate, and n is an integer greater than 1.

Optionally, in some embodiments, performing the multiple exposures on at least a portion of the pixels of the partial pixels includes: performing multiple exposures on the partial pixels.

Optionally, in some embodiments, performing the multiple exposures on the at least one of the partial pixels includes: performing multiple exposures on the at least one of the partial pixels according to the preset information, the preset information A distribution location of the at least a portion of the pixels in the portion of pixels is indicated.

Optionally, in some embodiments, the focus position is a location of the motor lens corresponding to a first image data of which the contrast is optimal in the plurality of first image data.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present invention are generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be from a website site, computer, server or data center Transmission to another website site, computer, server or data center via wired (eg coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (eg infrared, wireless, microwave, etc.). The computer readable storage medium can be any available media that can be accessed by a computer or a data storage device such as a server, data center, or the like that includes one or more available media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a digital video disc (DVD)), or a semiconductor medium (such as a solid state disk (SSD)). .

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods to implement the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present application.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

The foregoing is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application. It should be covered by the scope of protection of this application. Therefore, the scope of protection of the present application should be determined by the scope of the claims.

Claims

An image sensor, comprising:

a pixel array comprising a plurality of pixels arranged in a two-dimensional matrix, the pixels being light-sensing pixels;

a first control circuit is connected to a portion of the pixels in the pixel array, the first control circuit is configured to perform multiple exposures on at least a portion of the pixels in the moving process of the motor lens;

a first readout circuit, coupled to the partial pixel, the first readout circuit configured to read the first image data after each exposure of at least a portion of the pixels of the partial pixels;

The processing circuit is coupled to the first readout circuit, and the processing circuit is configured to perform contrast analysis on the plurality of first image data read by the first readout circuit to determine a focus position.
The image sensor according to claim 1, wherein the image sensor further comprises:

a second control circuit connected to all pixels in the pixel array, the second control circuit configured to perform at least one exposure on the pixels, wherein the performing at least one exposure on the pixels includes The focus position exposes all of the pixels;

a second readout circuit connected to the pixels, the first readout circuit configured to read the second image data after each exposure of the pixels;

The processing circuit is further connected to the second readout circuit, and the processing circuit is further configured to read out after the all the pixels are exposed at the focus position according to the second readout circuit. The second image data is obtained as an output image.
The image sensor according to claim 2, wherein the second control circuit is configured to perform multiple exposures on the pixels, including:

The second control circuit is configured to expose the pixels at the focus position when receiving a shutter signal;

The processing circuit is further configured to obtain an output image according to the second image data read by the second readout circuit after the all pixels are exposed at the focus position, including:

The processing circuit is configured to obtain the output according to the second image data read by the second readout circuit after the exposure of all the pixels based on the shutter signal, when the shutter signal is received image.
The image sensor according to claim 2 or 3, wherein the first control circuit is configured to expose at least a part of the pixels in the partial frame rate according to the first frame rate. The second control circuit is configured to expose the pixels according to a second frame rate, wherein the first frame rate is higher than the second frame rate.
The image sensor according to claim 4, wherein said first frame rate is n times said second frame rate, and n is an integer greater than one.
The image sensor according to any one of claims 1 to 5, wherein the partial pixels include pixels distributed in different rows or different columns of the pixel array.
The image sensor according to any one of claims 1 to 6, wherein the position of the partial pixels in the pixel array is preset.
The image sensor according to any one of claims 1 to 7, wherein the first control circuit is configured to perform multiple exposures on at least a part of the pixels of the partial pixels during movement of the motor lens, include:

The first control circuit is specifically configured to perform multiple exposures on the partial pixels during movement of the motor lens.
The image sensor according to any one of claims 1 to 7, wherein the first control circuit is configured to perform multiple exposures on at least a part of the pixels of the partial pixels during movement of the motor lens, include:

The first control circuit is configured to perform, according to the preset information, at least a part of the pixels in the partial lens during the movement of the motor lens, the preset information indicating that the part of the pixels is The location of the distribution of at least a portion of the pixels.
The image sensor according to claim 9, wherein in the different focus scenes, the distribution positions of the at least some of the pixels in the partial pixels are different.
The image sensor according to claim 9, wherein the distribution positions of the at least some of the pixels in the partial pixels corresponding to different exposure processes in the same focus scene are not completely the same.
The image sensor according to any one of claims 1 to 11, wherein the focus position is the motor corresponding to a first image data of which the contrast is optimal among the plurality of first image data The location of the lens.
The image sensor according to any one of claims 1 to 12, wherein the image sensor is a complementary metal oxide semiconductor CMOS image sensor.
A chip, comprising: the image sensor according to any one of claims 1 to 13.
An image processing apparatus comprising the image sensor according to any one of claims 1 to 13.
A method for controlling an image sensor, the image sensor comprising a pixel array, the pixel array comprising a plurality of pixels arranged in a two-dimensional matrix, the pixels being light-sensing pixels, the method comprising:

Performing multiple exposures on at least a portion of the pixels in the pixel array during movement of the motor lens;

Reading at least a portion of the pixels of the partial pixels after each exposure;

Performing contrast analysis on the read plurality of first image data to determine a focus position of the image sensor.
The method of claim 16 wherein the method further comprises:

Performing at least one exposure on all pixels in the pixel array, wherein the performing at least one exposure on the all pixels includes exposing the pixels in the focus position;

Reading the second image data after each exposure of the pixels;

An output image is obtained based on the second image data read out after the exposure of all the pixels at the focus position.
The method according to claim 17, wherein said performing multiple exposures on all pixels in said pixel array comprises:

Exposing all of the pixels at the focus position when receiving a shutter signal;

Obtaining an output image according to the second image data read after the all pixels are exposed at the focus position, comprising:

Upon receiving the shutter signal, the output image is obtained based on second image data read out after exposure of all of the pixels based on the shutter signal.
The method according to claim 17 or 18, wherein the performing the plurality of exposures on at least a part of the pixels in the pixel array comprises:

Performing multiple exposures on at least a portion of the partial pixels according to a first frame rate;

Performing multiple exposures on all pixels in the pixel array includes:

Multiple exposures are performed on all pixels in the pixel array at a second frame rate, wherein the first frame rate is higher than the second frame rate.
The method according to claim 19, wherein said first frame rate is n times said second frame rate, and n is an integer greater than one.
The method according to any one of claims 16 to 20, wherein the partial pixels include pixels distributed in different rows or different columns of the pixel array.
The method according to any one of claims 16 to 21, wherein the position of the partial pixels in the array of pixels is preset.
The method according to any one of claims 16 to 22, wherein the performing a plurality of exposures on at least a part of the pixels of the partial pixels comprises:

The partial pixels are subjected to multiple exposures.
The method according to any one of claims 16 to 22, wherein the performing a plurality of exposures on at least a part of the pixels of the partial pixels comprises:

And performing, according to the preset information, at least a part of the pixels in the partial pixels, wherein the preset information indicates a distribution position of the at least a part of the pixels in the partial pixels.
The method according to claim 24, wherein in the different focus scenes, the distribution positions of the at least some of the pixels in the partial pixels are different.
The method according to claim 24, wherein the distribution positions of the at least some of the pixels in the partial pixels corresponding to different exposure processes in the same focus scene are not completely the same.
The method according to any one of claims 16 to 26, wherein the focus position is the motor lens corresponding to a first image data of which the contrast is optimal among the plurality of first image data Where it is.