CN111556225B

CN111556225B - Image acquisition device and image acquisition control method

Info

Publication number: CN111556225B
Application number: CN202010428652.0A
Authority: CN
Inventors: 聂鑫鑫
Original assignee: Hangzhou Hikvision Digital Technology Co Ltd
Current assignee: Hangzhou Hikvision Digital Technology Co Ltd
Priority date: 2020-05-20
Filing date: 2020-05-20
Publication date: 2022-11-22
Anticipated expiration: 2040-05-20
Also published as: CN111556225A

Abstract

The application provides an image acquisition device and an image acquisition control method, and belongs to the technical field of computer vision. The image acquisition device includes: the device comprises an image sensor, a light supplementing device, a controller and a power supply for supplying power to the image acquisition device. The light supplement device performs near-infrared light supplement during the first preset exposure, and does not perform near-infrared light supplement during the second preset exposure. The controller acquires a synchronization signal from the power supply and transmits a first field synchronization signal to the image sensor according to the synchronization signal. The image sensor generates multiple exposures according to the first field synchronizing signal, generates and outputs a first image signal through the first preset exposure, and generates and outputs a second image signal through the second preset exposure. Because the controller carries out exposure control on the image sensor according to the synchronous signal generated by the power supply, a plurality of image acquisition devices can realize synchronous image acquisition, and the mutual interference among different image acquisition devices can be avoided.

Description

Image acquisition device and image acquisition control method

Technical Field

The application relates to the technical field of computer vision, in particular to an image acquisition device and an image acquisition control method.

Background

With the development of monitoring technology, the requirements of the monitoring field for the images acquired by the image acquisition device are higher and higher.

In order to improve the quality of the acquired images, many image acquisition devices support the acquisition of multispectral images. For example: the image acquisition device performs near-infrared supplementary lighting during the first preset exposure to generate a near-infrared image signal, and does not perform near-infrared supplementary lighting during the second preset exposure to generate a visible light image signal. And fusing the near-infrared light image signal and the visible light image signal to obtain a multispectral image. The image information embodied in the fused multispectral image is more, and the quality of the collected image is ensured.

However, in some application scenarios requiring a plurality of image capturing devices, interference may occur between different image capturing devices due to the installation positions, angles, and the like of the image capturing devices. For example: the image capturing device 1 may be affected by the near-infrared supplementary lighting of the image capturing device 2 during the second preset exposure process, so that the image capturing device 1 does not generate the visible light image signal through the second preset exposure.

Disclosure of Invention

The application provides an image acquisition device and an image acquisition control method, which are used for avoiding light supplement interference among different image acquisition devices.

In a first aspect, the present application provides an image capturing apparatus, comprising: the device comprises an image sensor, a light supplementing device, a controller and a power supply for supplying power to the image acquisition device, wherein the controller is respectively connected with the image sensor and the power supply;

the controller is used for acquiring a synchronous signal and sending a first field synchronous signal to the image sensor according to the synchronous signal; wherein the synchronization signal is a square wave pulse signal generated by the power supply;

the image sensor is used for generating multiple exposures according to the first field synchronizing signal, and generating and outputting a first image signal and a second image signal through the multiple exposures, wherein the first image signal is an image signal generated according to a first preset exposure, the second image signal is an image signal generated according to a second preset exposure, and the first preset exposure and the second preset exposure are two exposures of the multiple exposures;

the light supplement device comprises a first light supplement device, the first light supplement device is used for performing near-infrared light supplement, wherein the near-infrared light supplement is performed in at least part of the exposure time period of the first preset exposure, and the near-infrared light supplement is not performed in the exposure time period of the second preset exposure.

In a second aspect, the present application provides an image capturing control method, applied to an image capturing device, where the image capturing device includes: the image sensor, the light supplementing device and a power supply for supplying power to the image acquisition device are provided, and the method comprises the following steps:

acquiring a synchronous signal through the power supply, wherein the synchronous signal is a square wave pulse signal generated by the power supply;

sending a first field synchronizing signal to the image sensor according to the synchronizing signal, enabling the image sensor to generate multiple exposures according to the first field synchronizing signal, generating and outputting a first image signal through a first preset exposure, and generating and outputting a second image signal through a second preset exposure;

wherein the first and second preset exposures are two of the multiple exposures; and near-infrared supplementary lighting exists in at least part of the exposure time period of the first preset exposure, and near-infrared supplementary lighting does not exist in the exposure time period of the second preset exposure.

According to the image acquisition device and the image acquisition control method, the controller sends the first field synchronizing signal to the image sensor according to the synchronizing signal, and the synchronizing signal is generated by the power supply, so that the exposure time sequence of the image sensor is consistent with the synchronizing signal generated by the power supply. Therefore, in a scene that a plurality of image acquisition devices need to work simultaneously, the plurality of image acquisition devices all adopt the synchronous signals generated by the power supply to control the exposure time. Because the same synchronizing signal is adopted by the plurality of image acquisition devices, the exposure time sequences of the plurality of image acquisition devices are also synchronous, namely, the plurality of image acquisition devices simultaneously carry out the first preset exposure and the second preset exposure, thereby avoiding the mutual interference among different image acquisition devices.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

Fig. 1A is a schematic structural diagram of an image capturing device according to an embodiment of the present disclosure;

fig. 1B is a schematic diagram illustrating an image capturing principle of an image capturing apparatus according to an embodiment of the present disclosure;

fig. 2A is a schematic diagram of an exposure timing sequence and a near-infrared fill light timing sequence of an image capturing device in an embodiment of the present application;

fig. 2B is a schematic diagram of an exposure time sequence and a fill light time sequence of two image capturing devices with fill light interference;

fig. 3 is a schematic structural diagram of an image capturing device according to an embodiment of the present application;

fig. 4 is a schematic diagram of a synchronization signal and a first field synchronization signal provided in an embodiment of the present application;

FIG. 5 is a diagram illustrating the exposure control result according to the synchronization signal according to an embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of an image capturing device according to another embodiment of the present application;

fig. 7 is a schematic diagram of performing color cast analysis on a second image signal according to an embodiment of the present disclosure;

fig. 8 is a first diagram illustrating a result of performing exposure control according to a synchronization signal and a delay time according to an embodiment of the present application;

fig. 9 is a second schematic diagram illustrating a result of performing exposure control according to a synchronization signal and a delay time according to an embodiment of the present application;

fig. 10 is a schematic flowchart illustrating a process of controlling an image capturing device to enter a synchronous capturing mode according to an embodiment of the present application;

fig. 11 is a schematic flowchart of an image acquisition control method according to an embodiment of the present application;

fig. 12 is a schematic view illustrating a relationship between a wavelength and a relative intensity of near-infrared supplementary lighting performed by the first supplementary lighting device according to an embodiment of the present disclosure;

fig. 13 is a schematic diagram illustrating a relationship between a wavelength of light passing through the first optical filter and a transmittance of the light provided in the embodiment of the present application;

FIG. 14 is a schematic diagram of an RGB sensor provided in an embodiment of the present application;

FIG. 15 is a schematic diagram of an RGBW sensor provided by an embodiment of the present application;

FIG. 16 is a schematic diagram of an RCCB sensor according to an embodiment of the present application;

FIG. 17 is a schematic diagram of a RYYB sensor provided in accordance with an embodiment of the present application;

fig. 18 is a schematic diagram of an induction curve of an image sensor according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "first," "second," "third," "fourth," and the like in the description and claims of this application and in the preceding drawings, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Moreover, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

For ease of understanding, the structure and principle of the image pickup apparatus are first described with reference to fig. 1A and 1B.

Fig. 1A is a schematic structural diagram of an image acquisition device according to an embodiment of the present application. As shown in fig. 1A, the image capturing apparatus provided in this embodiment includes: the image sensor 01, the light supplement device 02 and the light filtering component 03. The image capturing device may further include a lens 04, and in this case, the filter assembly 03 may be located between the lens 04 and the image sensor 01, and the image sensor 01 is located on the light emitting side of the filter assembly 03. Alternatively, the lens 04 is located between the filter assembly 03 and the image sensor 01, and the image sensor 01 is located on the light emitting side of the lens 04.

Fig. 1B is a schematic diagram of an image acquisition principle of an image acquisition device according to an embodiment of the present application. As shown in fig. 1B, ambient light in the environment is reflected by the target object, and the fill light generated by the fill light device 02 is also reflected by the target object. The reflected light corresponding to the ambient light and the fill light enters the lens 04. The lens 04 collects the reflected light, and then filters the light through the filter assembly 03, so that only the reflected light with a specific wavelength band reaches the image sensor 01. The image sensor 01 generates an image signal by exposure.

In the present application, the image sensor 01 is configured to generate and output a first image signal and a second image signal by multiple exposures. The first image signal is an image signal generated according to a first preset exposure, the second image signal is an image signal generated according to a second preset exposure, and the first preset exposure and the second preset exposure are two exposures of the multiple exposures. The light supplement device 02 includes a first light supplement device 021, and the first light supplement device 021 is configured to perform near-infrared light supplement, wherein the near-infrared light supplement is performed during at least a part of the exposure time period of the first preset exposure, and the near-infrared light supplement is not performed during the exposure time period of the second preset exposure. The filter assembly 03 includes a first filter 031, and the first filter 031 passes visible light and a portion of near-infrared light.

Fig. 2A is a schematic diagram of an exposure timing sequence and a near-infrared fill light timing sequence of an image capture device in an embodiment of the present application. As shown in fig. 2A, the relationship between the exposure timing and the near-infrared fill light timing is: and avoiding the exposure time period of the second preset exposure to carry out near-infrared light supplement. That is, the starting time of the near-infrared supplementary lighting is equal to or later than the ending time of the last second preset exposure, and the ending time of the near-infrared supplementary lighting is earlier than or equal to the starting time of the next second preset exposure. In other words, the start time of the second preset exposure is not earlier than the end time of the last near-infrared supplementary lighting, and the end time of the second preset exposure is not later than the start time of the next near-infrared supplementary lighting.

In this way, the first image signal is generated by performing a first preset exposure through the image sensor, and near infrared light exists in at least a part of the exposure time period of the first preset exposure, so that the first image signal generated by the first preset exposure is a near infrared light image signal. The second image signal is generated by performing a second preset exposure through the image sensor, and near-infrared supplementary lighting is not performed within an exposure time period of the second preset exposure, so that the second image signal generated by the second preset exposure is a visible light image signal. Therefore, under the image fusion scene, the near infrared light image and the visible light image are fused, more image information is embodied in the fused image, and the quality of the acquired image is ensured.

However, there are some scenes in which it is necessary to install a plurality of image capturing devices at the same time. For example: community scenes, road traffic scenes, and the like. In these scenarios, interference may occur between different image capturing devices due to factors such as the installation position and angle of the image capturing devices. This is illustrated below in conjunction with fig. 2B. Assume that an image pickup apparatus 1 and an image pickup apparatus 2 are installed in a scene. The distance between the image acquisition device 1 and the image acquisition device 2 is short, or the image acquisition device 1 and the image acquisition device 2 are arranged oppositely. Fig. 2B is a schematic diagram of an exposure time sequence and a fill light time sequence of two image capturing devices with fill light interference. As shown in fig. 2B, when the image pickup apparatus 1 performs the second preset exposure, it is possible that the image pickup apparatus 2 is performing the first preset exposure. Therefore, the image capturing device 1 may be influenced by the near-infrared supplementary lighting of the image capturing device 2 during the second preset exposure process, so that the image capturing device 1 generates a non-visible image signal through the second preset exposure, thereby influencing the quality of the fused image.

In order to solve the above problem, an embodiment of the present application provides an image capturing device, which when being applied to a scene where a plurality of image capturing devices work together, can ensure the synchronization of capturing of the plurality of image capturing devices, that is, each image capturing device simultaneously performs a first preset exposure and simultaneously performs a second preset exposure, thereby avoiding mutual interference between different image capturing devices.

The technical solution of the present application will be described in detail below with specific examples. These several specific embodiments may be combined with each other below, and details of the same or similar concepts or processes may not be repeated in some embodiments.

Fig. 3 is a schematic structural diagram of an image capturing device according to an embodiment of the present application. As shown in fig. 3, the image capturing apparatus of this embodiment may further include a controller 05 and a power supply 06 on the basis of the image capturing apparatus shown in fig. 1A and 1B. The power supply 06 is used for supplying power to the image acquisition device. The controller 05 is connected to the image sensor 01 and the power supply 06, respectively.

The controller 05 is configured to acquire a synchronization signal and send a first field synchronization signal to the image sensor 01 according to the synchronization signal; wherein the synchronization signal is a square wave pulse signal generated by the power supply 06.

The image sensor 01 is configured to generate multiple exposures according to the first field synchronizing signal, and generate and output a first image signal and a second image signal through the multiple exposures, where the first image signal is an image signal generated according to a first preset exposure, the second image signal is an image signal generated according to a second preset exposure, and the first preset exposure and the second preset exposure are two exposures of the multiple exposures. The light supplement device 02 includes a first light supplement device 021, and the first light supplement device 021 is configured to perform near-infrared light supplement, where near-infrared light supplement is performed during at least a part of the exposure time period of the first preset exposure, and near-infrared light supplement is not performed during the exposure time period of the second preset exposure. The filter assembly 03 includes a first filter 031, and the first filter 031 passes visible light and a portion of near-infrared light.

The image acquisition device in the application can be a video camera, a snapshot machine, a face recognition camera, a code reading camera, a vehicle-mounted camera, a panoramic detail camera and the like. This is not a limitation of the present application.

Taking the structural feature that the filtering component 03 in the image capturing device may be located between the lens 04 and the image sensor 01, and the image sensor 01 is located on the light emitting side of the filtering component 03 as an example, the process of capturing the first image signal and the second image signal by the image capturing device is as follows: when the image sensor 01 performs the first preset exposure, the first light supplement device 021 performs near-infrared light supplement, and at this time, ambient light in a shooting scene and reflected light of the near-infrared light supplement reflected by an object in the scene pass through the lens 04 and the first optical filter 031, and then the image sensor 01 generates a first image signal through the first preset exposure. When the image sensor 01 performs the second preset exposure, the first light supplement device 021 does not perform near-infrared light supplement, and at this time, after reflected light of ambient light in a captured scene reflected by an object in the scene passes through the lens 04 and the first optical filter 031, the image sensor 01 generates a second image signal through the second preset exposure. There may be M first preset exposures and N second preset exposures within one frame period of image acquisition, and there may be a plurality of combinations of ordering between the first preset exposures and the second preset exposures. In a frame period of image acquisition, the values of M and N and the size relationship of M and N can be set according to actual requirements. For example, M and N may or may not be equal in value.

In some embodiments, the multiple exposure refers to multiple exposure within one frame period, that is, the image sensor 01 performs multiple exposures within one frame period, so as to generate and output at least one frame of the first image signal and at least one frame of the second image signal. For example, the image sensor 01 performs exposure for a plurality of times in each frame period including 25 frame periods within 1 second, thereby generating at least one frame of a first image signal and at least one frame of a second image signal, and the first image signal and the second image signal generated in one frame period are referred to as a set of image signals, so that 25 sets of image signals are generated in 25 frame periods. The first preset exposure and the second preset exposure may be adjacent two exposures in multiple exposures within one frame period, or may also be nonadjacent two exposures in multiple exposures within one frame period, which is not limited in this embodiment of the present application.

As an example, the light supplement device 02 may be located inside the image capturing device or outside the image capturing device. The light supplement 02 may be a part of the image capturing device or may be a device independent of the image capturing device. When the light supplement device 02 is located outside the image acquisition device, the light supplement device 02 can be in communication connection with the image acquisition device, so that the exposure time sequence of the image sensor 01 in the image acquisition device can be ensured to have a certain relation with the near-infrared light supplement time sequence of the first light supplement device 021 included in the light supplement device 02, if the first preset exposure is performed with near-infrared light supplement, and the second preset exposure is not performed with near-infrared light supplement.

In addition, the first light supplement device 021 is a device capable of emitting near infrared light, such as a near infrared light supplement lamp. First light filling device 021 can carry out near-infrared light filling with the stroboscopic mode, also can carry out near-infrared light filling with other modes of similar stroboscopic, and this application embodiment does not do the restriction to this. In some examples, when the first light supplement device 021 performs near-infrared light supplement in a stroboscopic manner, the first light supplement device 021 may be controlled in a manual manner to perform near-infrared light supplement in the stroboscopic manner, or the first light supplement device 021 may be controlled in a software program or a specific device to perform near-infrared light supplement in the stroboscopic manner, which is not limited in this embodiment. The time period of the first light supplement device 021 for performing near-infrared light supplement may coincide with the exposure time period of the current exposure, or may be smaller than the exposure time period of the current exposure.

In this embodiment, the image sensor 01 operates in a slave mode (which may also be referred to as a passive mode). In the slave mode, the field sync signal of the image sensor 01 is externally controlled. For example, in the present embodiment, the field sync signal of the image sensor 01 is controlled by the controller 05.

The controller 05 acquires a synchronization signal from the power supply 06 and transmits a field synchronization signal to the image sensor 01 according to the synchronization signal; wherein the synchronization signal is a square wave pulse signal generated by the power supply 06.

When the image acquisition device is in a working state, the image acquisition device is connected with a mains supply (for example, 220V alternating current) through an adapter power supply, acquires the mains supply from the mains supply, and converts the mains supply into electric energy required by the work of the image acquisition device. The power supply 06 may be an adapter power supply of the image capturing device, or may be a commercial power supply. It can be understood that whether the power supply is an adapter power supply of the image acquisition device or a mains power supply, the synchronization signal generated by the power supply 06 is a square wave pulse signal corresponding to the frequency of the mains power. For example: the frequency of the mains supply is typically 50Hz.

After acquiring the synchronization signal, the controller 05 transmits a field synchronization signal to the image sensor 01 according to the synchronization signal. The field sync signal may also be referred to as a field valid signal, and is generally used to control the start or end of one frame of image. In other words, in this embodiment, the controller 05 may control the start time or the end time of one frame of image of the image sensor, or in other words, the exposure timing of the image sensor, according to the synchronization signal. It should be noted that, in the present embodiment, for clarity of description and convenience of distinction, the field sync signal sent by the controller to the image sensor according to the sync signal is referred to as a first field sync signal. It can be understood that the first field sync signal is synchronized with the sync signal generated by the power supply.

In this embodiment, the controller transmits a first field sync signal to the image sensor according to the sync signal, wherein the first field sync signal includes a field sync signal of the first image signal and a field sync signal of the second image signal. Several situations may be included: (1) The controller controls a field sync signal of the first image signal to be synchronized with the sync signal. For example: the first field sync signal of the first image signal is transmitted at a rising edge (or a falling edge) of the sync signal, and the first field sync signal of the second image signal is transmitted based on the rising edge (or the falling edge) of the sync signal and a preset time interval (an exposure time period of the second preset exposure). (2) The controller controls a field sync signal of the second image signal to be synchronized with the sync signal. For example: the first field sync signal of the second image signal is transmitted at a rising edge (or a falling edge) of the sync signal, and the first field sync signal of the first image signal is transmitted based on the rising edge (or the falling edge) of the sync signal and a preset time interval (an exposure time period of the first preset exposure). (3) The controller controls both the field sync signal of the first image signal and the field sync signal of the second image signal to be synchronized with the sync signal. For example: the first field sync signal of the first image signal is transmitted at some rising edges (or falling edges) of the sync signal, and the first field sync signal of the second image signal is transmitted at other rising edges (or falling edges) of the sync signal.

This is illustrated below with reference to fig. 4. In fig. 4, the case (2) is described as an example, in which the controller controls the first field synchronizing signal of the second image signal to be synchronized with the rising edge of the synchronizing signal. Fig. 4 is a schematic diagram of a synchronization signal and a first field synchronization signal provided in an embodiment of the present application. As shown in fig. 4, VD denotes a first field sync signal of the second image signal (visible image signal), and VD' denotes a first field sync signal of the first image signal (near-infrared image signal). In one example, referring to fig. 4, the first field sync signal VD of the second image signal may be controlled according to a rising edge of a sync signal (square wave pulse signal). For example, the controller 05 transmits the first field sync signal VD of the second image signal to the image sensor 01 at a rising edge of the sync signal, and transmits the first field sync signal VD' of the first image signal with a delay of a preset time interval after the rising edge. It should be noted that fig. 4 illustrates a rising edge of the synchronization signal as an example, and in practical applications, the control may also be performed according to a falling edge of the synchronization signal as an example, and the specific principle is similar, and is not described herein again.

In this embodiment, the frequency of the synchronization signal generated by the power supply is an integer multiple of the output frame rate of the image sensor. The frequency of the synchronization signal refers to the frequency of the change of the high and low levels in the synchronization signal. It can be understood that, when the frequency of the synchronization signal is an integral multiple of the output frame rate of the image sensor, the exposure timing of the image sensor is controlled based on the rising edge or the falling edge of the synchronization signal, so that the control accuracy can be ensured, and the control accuracy can be maintained at a high level even after the integration of time. In one example, the frequency of the synchronization signal is 1 or 2 times the output frame rate of the image sensor. That is, the period of the synchronization signal is the same as the one-time exposure time period of the image sensor, or the period of the synchronization signal is the same as the two-time exposure time period of the image sensor. For example, if the output frame rate of the image sensor is 25, the frequency of the synchronization signal may be 25 or 50.

In this embodiment, the controller sends the first field synchronization signal to the image sensor according to the synchronization signal, and the synchronization signal is generated by the power supply, so that the exposure timing of the image sensor is consistent with the synchronization signal generated by the power supply. Therefore, in a scene that a plurality of image acquisition devices need to work simultaneously, the plurality of image acquisition devices all adopt the synchronous signals generated by the power supply to control the exposure time sequence. Because the same synchronizing signal is adopted by the plurality of image acquisition devices, the exposure time sequences of the plurality of image acquisition devices are also synchronous, namely, the plurality of image acquisition devices simultaneously carry out the first preset exposure and the second preset exposure, thereby avoiding the mutual interference among different image acquisition devices.

Fig. 5 is a diagram illustrating a result of performing exposure control on an exposure time according to a synchronization signal according to an embodiment of the present application. As shown in fig. 5, before the application is adopted, the exposure time sequences of the image capturing device 1 and the image capturing device 2 are different, and the image capturing device 1 may receive the influence of the near-infrared supplementary lighting of the image capturing device 2 when performing the second preset exposure. After adopting this application scheme, image acquisition device 1 and image acquisition device 2 are all controlled image sensor's exposure time sequence according to the rising edge of the synchronizing signal (the synchronizing signal that power supply produced) that is the same for image acquisition device 1 and image acquisition device 2 carry out the first exposure of predetermineeing simultaneously, and carry out the second simultaneously and predetermine the exposure, consequently, can avoid the interference of each other between the two.

However, in some scenarios, in a case where different image capturing devices control the exposure timing of the image sensor according to the synchronization signal generated by the power supply, there may still be mutual interference. For example: in conjunction with fig. 5, it is possible that the exposure time period of the first preset exposure of the image capturing device 1 just coincides with the exposure time period of the second preset exposure of the image capturing device 2, assuming that both image capturing devices control the exposure timing of the image sensor according to the same rising edge of the synchronization signal. Therefore, the image acquisition device 2 can receive the interference of the near-infrared supplementary lighting of the image acquisition device 1 when the second preset exposure is carried out. For another example: in some scenes, a plurality of image acquisition devices exist, some of the image acquisition devices support control over the exposure time sequence according to the synchronous signals generated by the power supply, and some of the image acquisition devices may not support control over the exposure time sequence according to the synchronous signals generated by the power supply, so that light supplement interference among different image acquisition devices may still exist.

To solve the above problem, in one possible embodiment, the controller 05 is further configured to: after a first field synchronizing signal is sent to the image sensor according to the synchronizing signal, a color cast parameter of a second image signal is acquired, a delay time is determined according to the color cast parameter, the delay time is delayed on the basis of the synchronizing signal to generate a second field synchronizing signal for replacing the first field synchronizing signal, and the second field synchronizing signal is sent to the image sensor (in the application, the field synchronizing signal sent to the image sensor after the controller delays the delay time on the basis of the synchronizing signal is called as the second field synchronizing signal). Illustratively, the time when the second field sync signal is transmitted to the image sensor is the time when the rising edge (or the falling edge) of the sync signal is added with the time corresponding to the delay time. The color cast parameter is used for indicating a pixel row subjected to near-infrared supplementary lighting interference in the second image signal.

It can be understood that the second field synchronizing signal is similar to the first field synchronizing signal, and the following cases can be included as well: (1) The controller transmits the second field sync signal of the first image signal according to a rising edge (or a falling edge) and a delay time of the sync signal. For example: the second field sync signal of the first image signal is transmitted based on a rising edge (or a falling edge) and a delay time of the sync signal, and the second field sync signal of the second image signal is transmitted based on a rising edge (or a falling edge) of the sync signal, the delay time, and a preset time interval (an exposure period of a second preset exposure). (2) The controller transmits a second field sync signal of the second image signal according to a rising edge (or a falling edge) and a delay time of the sync signal. For example: the second field sync signal of the second image signal is transmitted based on a rising edge (or a falling edge) and a delay time of the sync signal, and the second field sync signal of the first image signal is transmitted based on a rising edge (or a falling edge) of the sync signal, the delay time, and a preset time interval (an exposure period of the first preset exposure). (3) The controller transmits the first image signal and the second field sync signal of the second image signal according to a rising edge (or a falling edge) and a delay time of the sync signal. For example: the second field sync signal of the first image signal is transmitted based on some rising edges (or falling edges) and delay times of the sync signal, and the second field sync signal of the second image signal is transmitted based on other rising edges (or falling edges) and delay times of the sync signal.

For example, the controller 05 may acquire a second image signal generated by a second preset exposure from the image sensor 01, and analyze the second image signal to obtain the color cast parameter.

In another example, fig. 6 is a schematic structural diagram of an image capturing device according to another embodiment of the present application. As shown in fig. 6, on the basis of fig. 3, the image capturing apparatus of this embodiment may further include a processor 07. The processor 07 is configured to acquire the second image signal from the image sensor 01, and analyze the second image signal to obtain a color cast parameter. In this way, the controller 05 is specifically configured to retrieve the color cast parameters from the processor 07.

According to the photosensitive characteristic of the image sensor, when near-infrared supplementary lighting interference exists, the pixel values of all color channels in an image can show a certain rule. When the interference of the near-infrared supplementary lighting of different wave bands is received, the rules of the pixel values in the image may be different. Taking the near-infrared supplementary lighting interference near the 750nm wave band as an example, the R channel in the image has larger energy, the G channel has second energy, the B channel has the smallest energy, and the value of the R channel is far larger than that of the G channel and the B channel. Therefore, whether the controller 05 analyzes the second image signal or the processor 07 analyzes the second image signal, the color cast parameter can be obtained according to the pixel value of each color channel in the second image signal.

This is described below in conjunction with fig. 7. Fig. 7 is a schematic diagram of performing color cast analysis on a second image signal according to an embodiment of the present disclosure. As shown in fig. 7, the second image signal is an image generated by the image sensor through the second preset exposure after the first field sync signal is transmitted to the image sensor according to the sync signal. Assuming that the height of the image is H, the average of R, G, and B components can be obtained by performing statistics on every two lines of pixels, so that the length of the RGB average vector is H/2. According to the RGB mean value vector, whether all line pixels are interfered by near-infrared supplementary lighting or part of line pixels are interfered by infrared supplementary lighting can be judged. When the interference time of all the pixels of the rows subjected to the near-infrared supplementary lighting is the same, the RGB proportion trend of each row is approximate or the RGB proportion trend fluctuates within a certain range; when some row pixels are interfered by the near-infrared supplementary lighting, the RGB ratio changes slowly in a certain trend, and the longer the time of being interfered by the near-infrared supplementary lighting, the more the ratio of R gradually becomes, and the less the ratio of R gradually becomes otherwise. According to the characteristics, the color cast parameter (the pixel row of the second image signal subjected to the near-infrared supplementary lighting) of the second image signal can be determined.

Thus, the controller can estimate the required delay time according to the color cast parameter of the second image signal. Further, the controller controls the exposure timing of the image sensor based on the synchronization signal and the delay time, that is, the controller transmits the second field synchronization signal to the image sensor at a timing after the delay time is added to the rising/falling edge of the synchronization signal. When the controller controls the exposure time sequence of the image sensor, the delay time obtained according to the color cast parameter of the second image signal is also considered on the basis of the synchronous signal, so that the first preset exposure can be carried out by different image acquisition devices at the same time, the second preset exposure can be carried out at the same time, the precision of synchronous acquisition is improved, and the light supplement interference among different image acquisition devices is avoided.

The effect of performing synchronous acquisition control on different image acquisition devices in the embodiment of the present application is described below with reference to a specific application scenario. It is assumed that the application scenario includes an image capturing device 1 and an image capturing device 2, and the distance between the two image capturing devices is short, or the two image capturing devices are arranged opposite to each other. When the exposure time sequences of the two image acquisition devices are asynchronous, near-infrared light supplement interference can be generated between the two image acquisition devices. For example, when the image capture device 2 performs the second preset exposure (no near-infrared supplementary light exists), the image capture device 1 is performing the first preset exposure (near-infrared supplementary light exists), and thus the image capture device 2 may receive the near-infrared supplementary light of the image capture device 1, so that the image capture device 2 is interfered by the near-infrared supplementary light of the image capture device 1.

Fig. 8 is a first schematic diagram illustrating a result of performing exposure control according to a synchronization signal and a delay time according to an embodiment of the present application. In a possible case of the above application scenario, it is assumed that both the image capturing apparatus 1 and the image capturing apparatus 2 support the solution of the present embodiment. The image capturing apparatus 1 has completed the synchronous capturing control according to the scheme of the present embodiment, and referring to fig. 8, the exposure timing of the image capturing apparatus 1 coincides with the rising edge of the synchronous signal. However, the image capturing apparatus 2 has not completed the synchronous capturing control, and for example, in fig. 8, although the exposure time of the image capturing apparatus 2 also coincides with the rising edge of the synchronization signal, the exposure time period of the second preset exposure of the image capturing apparatus 2 coincides with the exposure time period of the first preset exposure of the image capturing apparatus 1. Therefore, in this case, the image capturing device 2 may be interfered by the near-infrared fill light of the image capturing device 1.

In this case, the synchronous acquisition control process of the present embodiment may be executed by the image acquisition device 2 to avoid the above-described interference situation. Specifically, the image capture device 2 obtains a color cast parameter by analyzing a second image signal generated by the second preset exposure, and then determines a delay time according to the color cast parameter, for example, the delay time determined in fig. 8 is a square wave period. Further, the controller of the image pickup device 2 transmits a field synchronizing signal to the image sensor with the delay time (one square wave period) based on the synchronizing signal to perform synchronous pickup control. Referring to fig. 8, after the image capturing device 2 completes the synchronous capturing control, the first preset exposure of the image capturing device 2 is synchronized with the first preset exposure of the image capturing device 1, and the second preset exposure of the image capturing device 2 is synchronized with the second preset exposure of the image capturing device 1. Thus, mutual interference between the image pickup device 1 and the image pickup device 2 does not occur.

Fig. 9 is a diagram illustrating a second result of performing exposure control according to the synchronization signal and the delay time according to the embodiment of the present application. In another possible case of the above application scenario, it is assumed that the image capturing apparatus 1 does not support the scheme of the present embodiment (i.e., does not support exposure control according to the synchronization signal of the power supply), and the image capturing apparatus 2 supports the scheme of the present embodiment. As shown in fig. 9, the exposure time of the image capturing device 2 is already consistent with the rising edge of the synchronization signal, but since the image capturing device 1 does not support exposure control according to the synchronization signal, the exposure time of the image capturing device 1 is not consistent with the rising edge of the synchronization signal, so that the image capturing device 2 may be interfered by the near-infrared supplementary lighting of the image capturing device 1.

In this case, the above-described interference process can be avoided by the image pickup device 2 executing the synchronous pickup control process of the present embodiment. Specifically, the image capture device 2 obtains a color cast parameter by analyzing a second image signal generated by the second preset exposure, and then determines a delay time according to the color cast parameter, for example, the delay time determined in fig. 9 is less than a square wave period. Further, the controller of the image pickup device 2 delays the delay time based on the synchronization signal to send a field synchronization signal to the image sensor, thereby completing the synchronous pickup control. Referring to fig. 9, after the image capturing device 2 completes the synchronous capturing control, the first preset exposure of the image capturing device 2 is synchronized with the first preset exposure of the image capturing device 1, and the second preset exposure of the image capturing device 2 is synchronized with the second preset exposure of the image capturing device 1. Thus, mutual interference between the image pickup device 1 and the image pickup device 2 does not occur.

In a possible implementation manner, the image capturing apparatus of this embodiment may include two operation modes, one is a mode in which synchronous capturing is performed according to a synchronization signal of the power supply (referred to as a synchronous capturing mode in this application), and the other is a mode in which synchronous capturing is not performed according to a synchronization signal of the power supply (referred to as an asynchronous capturing mode in this application). In some scenarios, the user may manually set the operating mode of the image capture device. For example, when it is desired to operate the image capturing device in the synchronous capturing mode, the user may input a synchronous capturing instruction to the controller of the image capturing device. Thus, the controller controls the image acquisition device to enter the synchronous acquisition mode after receiving the synchronous acquisition command input by the user. In other scenarios, the trigger conditions of the two operation modes of the image capturing device may be set in advance. The trigger condition may be set according to a time period, and may also be set according to an environmental parameter. For example, the day (08; or, the environment parameter works in the asynchronous acquisition mode when located in the first range, and works in the synchronous acquisition mode when located in the second range. And when the controller detects that the current time and/or the current environmental parameters meet the trigger conditions corresponding to the synchronous acquisition mode, controlling the image acquisition device to enter a synchronous acquisition flow.

Fig. 10 is a schematic flowchart of controlling an image capturing device to enter a synchronous capturing mode according to an embodiment of the present application. The control method can be applied to an image pickup apparatus as shown in fig. 6. As shown in fig. 10, includes:

s101: the controller obtains the synchronous signal from the power supply when receiving a synchronous acquisition instruction input by a user or detecting that the current time and/or the current environmental parameters meet a preset trigger condition.

The preset trigger condition may refer to a trigger condition set in advance for the synchronous acquisition mode.

S102: the controller sends a first field synchronization signal to the image sensor according to the synchronization signal.

S103: the controller acquires a color cast parameter of a second image signal generated by the image sensor through a second preset exposure.

It can be understood that the second image signal is generated by a second preset exposure of the multiple exposures by the image sensor according to the first field sync signal. Illustratively, the processor acquires a second image signal from the image sensor, and analyzes pixel values of each color channel in the second image signal to obtain a color cast parameter; the controller obtains the color cast parameter from the processor.

S104: the controller judges whether the second image signal has color cast according to the color cast parameter. If no color cast, the process is finished. If the color is off, S105 is executed.

S105: the controller determines a delay time according to the color cast parameter, delays the delay time on the basis of the synchronizing signal to generate a second field synchronizing signal for replacing the first field synchronizing signal, and transmits the second field synchronizing signal to the image sensor.

For the specific implementation of S101 to S105, reference may be made to the detailed description of the above embodiments, which is not described herein again.

S106: the processor acquires a color cast parameter of a second image signal generated by the image sensor through a second preset exposure.

It can be understood that the second image signal is generated by a second preset exposure of the multiple exposures by the image sensor according to the second field sync signal.

S107: the processor judges whether the second image signal has color cast according to the color cast parameters. If no color cast, the process is finished. If the color is off, S108 is executed.

S108: the processor performs a color cast correction process on the second image signal.

In some scenarios, S106 to S108 of the present embodiment may also be performed after the controller controls the exposure timing of the image sensor according to the synchronization signal and the delay time. That is to say, the processor performs color cast analysis on the second image signal again, and if the second image signal still has color cast, it indicates that interference of the near-infrared supplementary lighting of other image acquisition devices still cannot be avoided after the scheme of this embodiment is adopted (for example, the other image acquisition devices perform the near-infrared supplementary lighting in a normally-on manner, or perform the near-infrared supplementary lighting in a stroboscopic manner, but the duration of the near-infrared supplementary lighting is longer than the square wave period in the synchronization signal). Therefore, in order to ensure the quality of the acquired image, the processor may perform a color cast correction process on the second image signal, for example: adjusting pixel values of each color channel in the second image signal to eliminate color cast; or converting the second image signal into a black-and-white image to eliminate the interference of the near-infrared supplementary lighting. Of course, the processor may also perform other color cast correction processing on the second image signal, which is not limited in this embodiment.

In addition, when it is determined that the second image signal still has color cast according to the color cast parameter obtained in S106, the controller may control the image capturing device to still operate in the synchronous capturing mode, or may control the image capturing device to switch to the asynchronous capturing mode. For example, in the asynchronous acquisition mode, the first light supplement device may not adopt an alternate light supplement manner (e.g., the first light supplement device is normally on or the first light supplement device is not on). In this embodiment, the control flow of the controller in the case that the second image signal still has color cast in S106 is not limited.

It should be noted that, in this embodiment, the synchronous acquisition process only needs to be executed once when the synchronous acquisition mode is switched.

On the basis of the above embodiments, in some embodiments, the filter assembly 03 further includes a second filter and a switching component, and the first filter 031 and the second filter are both connected to the switching component; the switching component is configured to switch the second optical filter to the light incident side of the image sensor 01, or switch the first optical filter 031 to the light incident side of the image sensor 01. For example, the second filter is switched to the light incident side of the image sensor 01 during the daytime, and the first filter 031 is switched to the light incident side of the image sensor 01 during the night. After the second optical filter is switched to the light incident side of the image sensor 01, the second optical filter allows visible light to pass through and blocks near infrared light, and the image sensor 01 is used for generating and outputting a third image signal through exposure.

It should be noted that the switching member is used to switch the second optical filter to the light incident side of the image sensor 01, and the second optical filter may be understood to replace the position of the first optical filter 031 on the light incident side of the image sensor 01. After the second filter is switched to the light incident side of the image sensor 01, the first light supplement device 021 may be in an off state or an on state.

In this embodiment, in order to make the first light supplement device 021 and the first optical filter 031 have a better fit, the center wavelength of the near-infrared light supplement performed by the first light supplement device 021 can be designed, and the characteristics of the first optical filter 031 can be selected, so that when the center wavelength of the near-infrared light supplement performed by the first light supplement device 021 is the set characteristic wavelength or falls within the set characteristic wavelength range, the center wavelength and/or the band width of the near-infrared light passing through the first optical filter 031 can reach the constraint condition. The constraint condition is mainly used to constrain the center wavelength of the near-infrared light passing through the first optical filter 031 to be as accurate as possible, and the band width of the near-infrared light passing through the first optical filter 031 to be as narrow as possible, so as to avoid the occurrence of wavelength interference caused by too wide band width of the near-infrared light.

The central wavelength of the near-infrared light supplement by the first light supplement device 021 may be an average value in a wavelength range where energy in a spectrum of the near-infrared light emitted by the first light supplement device 021 is the maximum, or may be a wavelength at an intermediate position in a wavelength range where energy in the spectrum of the near-infrared light emitted by the first light supplement device 021 exceeds a certain threshold.

The set characteristic wavelength or the set characteristic wavelength range may be preset. As an example, the center wavelength of the near-infrared supplementary light performed by the first supplementary light device 021 may be any wavelength within a wavelength range of 750 ± 10 nanometers; or, the center wavelength of the near-infrared supplementary lighting performed by the first supplementary lighting device 021 is any wavelength within the wavelength range of 780 ± 10 nanometers; or, the first light supplement device 021 supplements light in near-infrared light at any wavelength within a wavelength range of 940 ± 10 nanometers. That is, the set characteristic wavelength range may be a wavelength range of 750 ± 10 nanometers, or a wavelength range of 780 ± 10 nanometers, or a wavelength range of 940 ± 10 nanometers. Illustratively, the center wavelength of the first light supplement device 021 for near-infrared light supplement is 940 nm, and the relationship between the wavelength and the relative intensity of the first light supplement device 021 for near-infrared light supplement is shown in fig. 12. As can be seen from fig. 12, the wavelength band of the first light supplement device 021 for performing near-infrared light supplement is 900 nm to 1000 nm, wherein at 940 nm, the relative intensity of the near-infrared light is the highest.

Since most of the near-infrared light passing through the first light supplement device 031 is near-infrared light reflected by the object and entering the first light supplement device 031 when the first light supplement device 021 performs near-infrared light supplement when performing near-infrared light supplement, in some embodiments, the constraint conditions may include: the difference between the central wavelength of the near-infrared light passing through the first filter 031 and the central wavelength of the near-infrared light supplementary filling performed by the first light supplementary filling device 021 is within a wavelength fluctuation range, which may be 0 to 20 nm, as an example.

The central wavelength of the near-infrared supplementary light passing through the first optical filter 031 may be a wavelength at a peak position in a near-infrared band range in the near-infrared light transmittance curve of the first optical filter 031, or may be a wavelength at a middle position in a near-infrared band range in which the transmittance exceeds a certain threshold value in the near-infrared light transmittance curve of the first optical filter 031.

In order to avoid introducing wavelength interference due to too wide band width of the near infrared light passing through the first filter 031, in some embodiments, the above constraint may include: the first band width may be less than the second band width. The first wavelength band width refers to the wavelength band width of the near-infrared light passing through the first filter 031, and the second wavelength band width refers to the wavelength band width of the near-infrared light blocked by the first filter 031. It should be understood that the bandwidth refers to the width of the wavelength range in which the wavelength of the light is located. For example, the wavelength of the near infrared light passing through the first filter 031 is in the wavelength range of 700 nm to 800 nm, and then the first wavelength band width is 800 nm minus 700 nm, i.e., 100 nm. In other words, the wavelength band width of the near infrared light passing through the first filter 031 is smaller than the wavelength band width of the near infrared light blocked by the first filter 031.

For example, referring to fig. 13, fig. 13 is a schematic diagram illustrating a relationship between a wavelength of light that can pass through the first filter 031 and a pass rate. The band of the near-infrared light incident to the first optical filter 031 is 650 nm to 1100 nm, the first optical filter 031 allows visible light having a wavelength of 380 nm to 650 nm to pass through, near-infrared light having a wavelength of 900 nm to 1100 nm to pass through, and near-infrared light having a wavelength of 650 nm to 900 nm to be blocked. That is, the first band width is 1000 nanometers minus 900 nanometers, i.e., 100 nanometers. The second band has a width of 900 nm minus 650 nm plus 1100 nm minus 1000 nm, i.e., 350 nm. The wavelength band width of the near infrared light passing through the first filter 031 is less than the wavelength band width of the near infrared light blocked by the first filter 031, which is less than 100 nm and less than 350 nm. The above relation is only an example, and the wavelength range of the near-red light band that can pass through the filter may be different for different filters, and the wavelength range of the near-infrared light that is blocked by the filter may also be different.

In order to avoid introducing wavelength interference due to too wide band width of the near-infrared light passing through the first filter 031 during the non-near-infrared light supplement period, in some embodiments, the constraint conditions may include: the half-bandwidth of the near infrared light passing through the first filter 031 is less than or equal to 50 nm. The half bandwidth refers to the band width of near infrared light with a passing rate of more than 50%.

In order to avoid introducing wavelength interference due to too wide band width of the near infrared light passing through the first filter 031, in some embodiments, the constraint conditions may include: the third band width may be less than the reference band width. The third wavelength band width refers to a wavelength band width of the near infrared light having a transmittance greater than a set ratio, and as an example, the reference wavelength band width may be any one of wavelength band widths in a wavelength band range of 50nm to 100 nm. The set proportion may be any proportion of 30% to 50%, and certainly, the set proportion may be set to other proportions according to use requirements, which is not limited in the embodiment of the present application. In other words, the band width of the near infrared light having the passing rate larger than the set ratio may be smaller than the reference band width.

For example, referring to fig. 13, the wavelength band of the near infrared light incident to the first filter 031 is 650 nm to 1100 nm, the set ratio is 30%, and the reference wavelength band width is 100 nm. As can be seen from fig. 13, in the wavelength band of the near-infrared light of 650 nm to 1100 nm, the wavelength band width of the near-infrared light with the transmittance of more than 30% is significantly less than 100 nm.

The first image signal is generated and output for a first preset exposure, the second image signal is generated and output for a second preset exposure, and the first image signal and the second image signal may be processed after the first image signal and the second image signal are generated and output. In some cases, the first image signal and the second image signal may be used differently, so in some embodiments, at least one exposure parameter of the first preset exposure and the second preset exposure may be different. As an example, the at least one exposure parameter may include, but is not limited to, one or more of exposure time, analog gain, digital gain, aperture size. Wherein the exposure gain comprises an analog gain and/or a digital gain.

In other embodiments, the first image signal and the second image signal may be used in the same purpose, for example, when both the first image signal and the second image signal are used for intelligent analysis, at least one exposure parameter of the first preset exposure and the second preset exposure may be the same in order to enable the same definition of the human face or the target under intelligent analysis when the human face or the target moves. As an example, the exposure time of the first preset exposure may be equal to the exposure time of the second preset exposure, and if the exposure time of the first preset exposure is different from the exposure time of the second preset exposure, a motion smear may exist in one path of image signals with a longer exposure time, resulting in different resolutions of the two paths of image signals. Likewise, as another example, the exposure gain of the first preset exposure may be equal to the exposure gain of the second preset exposure.

It is noted that, in some embodiments, when the exposure time of the first preset exposure is equal to the exposure time of the second preset exposure, the exposure gain of the first preset exposure may be smaller than or equal to the exposure gain of the second preset exposure. Similarly, when the exposure gain of the first preset exposure is equal to the exposure gain of the second preset exposure, the exposure time of the first preset exposure may be shorter than the exposure time of the second preset exposure, or may be equal to the exposure time of the second preset exposure.

The image sensor 01 may be a single CMOS sensor including a plurality of sensing channels, each of which may be configured to sense at least one visible wavelength band of light and to sense near infrared wavelength band of light. That is, each light sensing channel can sense light of at least one visible light band and can sense light of a near infrared band. Alternatively, the plurality of sensing channels may be adapted to sense light in at least two different visible wavelength bands.

In some embodiments, the plurality of photosensitive channels may include at least two of an R photosensitive channel, a G photosensitive channel, a B photosensitive channel, a Y photosensitive channel, a W photosensitive channel, and a C photosensitive channel. The light sensing device comprises a light sensing channel, a light sensing channel Y, a light sensing channel R, a light sensing channel G, a light sensing channel B and a light sensing channel Y, wherein the light sensing channel R is used for sensing light of a red light wave band and a near infrared wave band, the light sensing channel G is used for sensing light of a green light wave band and a near infrared wave band, the light sensing channel B is used for sensing light of a blue light wave band and a near infrared wave band, and the light sensing channel Y is used for sensing light of a yellow light wave band and a near infrared wave band. Since in some embodiments, the photosensitive channel for sensing the light of the full wavelength band may be denoted by W, and in other embodiments, the photosensitive channel for sensing the light of the full wavelength band may be denoted by C, when the plurality of photosensitive channels include the photosensitive channel for sensing the light of the full wavelength band, the photosensitive channel may be the photosensitive channel of W, and may also be the photosensitive channel of C. That is, in practical applications, the photosensitive channel for sensing the light of the full wavelength band can be selected according to the use requirement. Illustratively, the image sensor 01 may be an RGB sensor, an RGBW sensor, or an RCCB sensor, or an ryb sensor. The distribution of the R, G, B, and W photosensitive channels in the RGB sensor may be shown in fig. 14, the distribution of the R, G, B, and W photosensitive channels in the rgbw sensor may be shown in fig. 15, the distribution of the R, C, and B photosensitive channels in the rccb sensor may be shown in fig. 16, and the distribution of the R, Y, and B photosensitive channels in the ryyb sensor may be shown in fig. 17.

In other embodiments, some of the sensing channels may sense only light in the near infrared band and not light in the visible band. As an example, the plurality of photosensitive channels may include at least two of an R photosensitive channel, a G photosensitive channel, a B photosensitive channel, and an IR photosensitive channel. The R light sensing channel is used for sensing light of a red light wave band and a near infrared wave band, the G light sensing channel is used for sensing light of a green light wave band and a near infrared wave band, the B light sensing channel is used for sensing light of a blue light wave band and a near infrared wave band, and the IR light sensing channel is used for sensing light of a near infrared wave band.

Illustratively, the image sensor 01 may be an rgbiir sensor, wherein each IR photosensitive channel in the rgbiir sensor may sense light in the near infrared band, but not light in the visible band.

When the image sensor 01 is an RGB sensor, compared with other image sensors such as an rgbiir sensor, RGB information acquired by the RGB sensor is more complete, and a part of photosensitive channels of the rgbiir sensor cannot acquire visible light, so that color details of an image acquired by the RGB sensor are more accurate.

It is noted that the image sensor 01 may include a plurality of photosensitive channels corresponding to a plurality of sensing curves. Illustratively, referring to fig. 18, an R curve in fig. 18 represents a sensing curve of the image sensor 01 for light in a red wavelength band, a G curve represents a sensing curve of the image sensor 01 for light in a green wavelength band, a B curve represents a sensing curve of the image sensor 01 for light in a blue wavelength band, a W (or C) curve represents a sensing curve of the image sensor 01 for light in a full wavelength band, and an NIR (Near infrared) curve represents a sensing curve of the image sensor 01 for light in a Near infrared wavelength band.

Since human eyes easily mix the color of the near-infrared light supplement performed by the first light supplement device 021 with the color of the red light in the traffic light, the light supplement device 02 may further include a second light supplement device for supplementing visible light. The second light supplementing device can supplement visible light in at least part of the exposure time period of the first preset exposure and/or the second preset exposure. Taking the first preset exposure as an example, if the second light supplement device provides the visible light supplement within at least a part of the exposure time period of the first preset exposure, that is, at least the near-infrared light supplement and the visible light supplement are performed within the part of the exposure time period of the first preset exposure, the mixed color of the two lights can be different from the color of the red light in the traffic light, so that the confusion of the color of the near-infrared light supplement performed by the light supplement device 02 by human eyes and the color of the red light in the traffic light is avoided, and the quality of image acquisition is ensured.

In some embodiments, the second light supplement device may be configured to supplement the visible light in a normally bright manner; or, the second light supplement device may be configured to supplement the visible light in a stroboscopic manner, where the supplementary visible light exists in at least part of the exposure time period of the first preset exposure, and the supplementary visible light does not exist in the entire exposure time period of the second preset exposure; or, the second light supplement device may be configured to supplement visible light in a stroboscopic manner, where the supplement visible light does not exist within the entire exposure time period of the first preset exposure, and the supplement visible light exists within at least a part of the exposure time period of the second preset exposure; or the second light supplement device is configured to supplement the visible light in a stroboscopic manner, where the supplementary visible light exists in at least part of the exposure time period of the first preset exposure, and the supplementary visible light exists in at least part of the exposure time period of the second preset exposure. The time period of the visible light supplementary lighting and the time period of the near-infrared supplementary lighting can be the same or different.

When the second light supplement device is normally on, visible light is supplemented, so that the situation that the color of the first light supplement device 021 for near-infrared light supplement is mixed with the color of a red light in a traffic light by human eyes can be avoided, and the quality of image acquisition is also ensured. When the second light filling device carries out visible light filling with the stroboscopic mode, can avoid the colour that the human eye carries out near-infrared light filling with first light filling device 021 and the colour of the red light in the traffic light to obscure, and then guarantee image acquisition's quality, but also can reduce the light filling number of times of second light filling device to the life of extension second light filling device.

Based on the above description of the image pickup apparatus, the image pickup apparatus can generate and output the first image signal and the second image signal by a plurality of exposures. Next, an image capture control method will be described with reference to the image capture device provided based on the above-described embodiment. Fig. 11 is a schematic flowchart of an image acquisition control method according to an embodiment of the present application. The method of the present embodiment may be performed by the image capturing apparatus in the above embodiments. As shown in fig. 11, the method of the present embodiment includes:

s111: the method comprises the steps of obtaining a synchronous signal through a power supply, wherein the synchronous signal is a square wave pulse signal generated by the power supply.

S112: and sending a first field synchronizing signal to the image sensor according to the synchronizing signal, so that the image sensor generates multiple exposures according to the first field synchronizing signal, generates and outputs a first image signal through a first preset exposure, and generates and outputs a second image signal through a second preset exposure.

Wherein the first and second pre-set exposures are two exposures of the multiple exposures; and near-infrared supplementary lighting exists in at least part of the exposure time period of the first preset exposure, and near-infrared supplementary lighting does not exist in the exposure time period of the second preset exposure.

In one possible implementation, after sending the first field synchronization signal to the image sensor according to the synchronization signal, the method further includes: acquiring a color cast parameter of the second image signal, and determining delay time according to the color cast parameter; delaying the delay time on the basis of the synchronization signal to generate a second field synchronization signal for replacing the first field synchronization signal, and transmitting the second field synchronization signal to the image sensor; the color cast parameter is used for indicating a pixel row subjected to near-infrared supplementary lighting interference in the second image signal.

In one possible implementation, the acquiring the color cast parameter of the second image signal includes: and acquiring the second image signal from the image sensor, and acquiring a color cast parameter according to the pixel value of each color channel in the second image signal.

In one possible implementation, after sending the second field synchronization signal to the image sensor, the method further includes:

acquiring a color cast parameter of the second image signal;

and when the color cast degree indicated by the color cast parameter is greater than or equal to a preset threshold value, performing color cast correction processing on the second image signal.

In one possible implementation, the frequency of the synchronization signal is an integer multiple of the output frame rate of the image sensor, and the frequency of the synchronization signal refers to the variation frequency of high and low levels inside the synchronization signal.

In one possible implementation, the frequency of the synchronization signal is 1 or 2 times the output frame rate of the image sensor.

In one possible implementation, the acquiring, by the power supply, a synchronization signal includes: when receiving a synchronous acquisition instruction input by a user, acquiring the synchronous signal from the power supply; or when detecting that the current time and/or the current environmental parameter meet a preset trigger condition, acquiring the synchronous signal from the power supply.

It should be noted that, since the present embodiment and the above embodiments may adopt the same inventive concept, for the explanation of the present embodiment, reference may be made to the explanation of the relevant contents in the above embodiments, and details are not described herein again.

In the embodiment of the application, because the controller performs exposure control on the image sensor based on the synchronization signal generated by the power supply, in a scene in which a plurality of image acquisition devices need to work simultaneously, the plurality of image acquisition devices perform exposure control on the image sensor based on the synchronization signal generated by the power supply. Because a plurality of image acquisition devices are based on the same synchronizing signal, consequently, a plurality of image acquisition devices's exposure chronogenesis is synchronous also, promptly, a plurality of image acquisition devices carry out first preset exposure simultaneously to and, carry out the second simultaneously and predetermine the exposure, thereby can avoid the mutual interference between the different image acquisition device.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The foregoing program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An image acquisition apparatus, comprising: the device comprises an image sensor, a light supplementing device, a controller and a power supply for supplying power to the image acquisition device, wherein the controller is respectively connected with the image sensor and the power supply;

the controller is used for acquiring a synchronous signal and sending a first field synchronous signal to the image sensor according to the synchronous signal so as to enable the exposure time sequence of the image sensor to be consistent with the synchronous signal generated by the power supply; wherein the synchronization signal is a square wave pulse signal generated by the power supply; when a plurality of image acquisition devices acquire images simultaneously, the exposure time sequences of the image acquisition devices are synchronous;

the image sensor is used for generating multiple exposures according to the first field synchronizing signal, generating and outputting a first image signal and a second image signal through the multiple exposures, wherein the first image signal is an image signal generated according to a first preset exposure, the second image signal is an image signal generated according to a second preset exposure, and the first preset exposure and the second preset exposure are two exposures of the multiple exposures;

the light supplement device comprises a first light supplement device, the first light supplement device is used for performing near-infrared light supplement, wherein near-infrared light supplement is performed in at least part of the exposure time period of the first preset exposure, and near-infrared light supplement is not performed in the exposure time period of the second preset exposure.

2. The image capturing apparatus as claimed in claim 1, wherein the controller is further configured to obtain a color shift parameter of the second image signal after sending a first field sync signal to the image sensor according to the synchronization signal, determine a delay time according to the color shift parameter, delay the delay time based on the synchronization signal to generate a second field sync signal for replacing the first field sync signal, and send the second field sync signal to the image sensor, so that the image sensor generates multiple exposures according to the second field sync signal; the color cast parameter is used for indicating a pixel row subjected to near-infrared supplementary lighting interference in the second image signal.

3. The image capturing apparatus according to claim 2, further comprising a processor, wherein the processor is configured to obtain the second image signal from the image sensor, and obtain a color cast parameter according to a pixel value of each color channel in the second image signal; the controller is specifically configured to obtain the color cast parameter from the processor.

4. The image capturing apparatus according to claim 3, wherein after the controller sends the second field sync signal to the image sensor, the processor is further configured to obtain a color cast parameter of the second image signal, and perform a color cast correction process on the second image signal when a color cast degree indicated by the color cast parameter is greater than or equal to a preset threshold.

5. The image capturing device according to any one of claims 1 to 4, wherein the frequency of the synchronization signal is an integer multiple of an output frame rate of the image sensor, and the frequency of the synchronization signal refers to a variation frequency of high and low levels inside the synchronization signal.

6. The image capturing device according to claim 5, wherein the frequency of the synchronization signal is 1 or 2 times the output frame rate of the image sensor.

7. The image acquisition apparatus according to any one of claims 1 to 4, wherein the controller is specifically configured to:

when a synchronous acquisition instruction input by a user is received, acquiring the synchronous signal from the power supply, and sending a first field synchronous signal to the image sensor according to the synchronous signal;

alternatively, the first and second electrodes may be,

and when detecting that the current time and/or the current environmental parameters meet a preset trigger condition, acquiring the synchronous signal from the power supply, and sending a first field synchronous signal to the image sensor according to the synchronous signal.

8. An image acquisition control method is applied to an image acquisition device, and the image acquisition device comprises: the image sensor, light filling ware and be used for to the power supply of image acquisition device power supply, the method includes:

sending a first field synchronizing signal to the image sensor according to the synchronizing signal, so that the image sensor generates multiple exposures according to the first field synchronizing signal, generates and outputs a first image signal through first preset exposure, and generates and outputs a second image signal through second preset exposure;

wherein the first and second pre-set exposures are two exposures of the multiple exposures; near-infrared supplementary lighting exists in at least part of the exposure time period of the first preset exposure, and near-infrared supplementary lighting does not exist in the exposure time period of the second preset exposure;

the exposure time sequence of the image sensor is consistent with the synchronous signal generated by the power supply, and when a plurality of image acquisition devices acquire images simultaneously, the exposure time sequences of the plurality of image acquisition devices are synchronous.

9. The method of claim 8, wherein after sending the first field sync signal to the image sensor according to the sync signal, further comprising:

acquiring a color cast parameter of the second image signal, and determining delay time according to the color cast parameter, wherein the color cast parameter is used for indicating a pixel row subjected to near-infrared supplementary lighting interference in the second image signal;

delaying the delay time on the basis of the synchronizing signal to generate a second field synchronizing signal for replacing the first field synchronizing signal, and sending the second field synchronizing signal to the image sensor, so that the image sensor generates multiple exposures according to the second field synchronizing signal.

10. The method of claim 9, wherein the obtaining the color cast parameter of the second image signal comprises:

and acquiring the second image signal from the image sensor, and acquiring a color cast parameter according to the pixel value of each color channel in the second image signal.

11. The method of claim 10, wherein after sending the second field sync signal to the image sensor, further comprising:

acquiring a color cast parameter of the second image signal;

12. The method according to any one of claims 8 to 11, wherein the frequency of the synchronization signal is an integer multiple of the output frame rate of the image sensor, and the frequency of the synchronization signal refers to the variation frequency of high and low levels inside the synchronization signal.

13. The method of claim 12, wherein the frequency of the synchronization signal is 1 or 2 times the output frame rate of the image sensor.

14. The method according to any one of claims 8 to 11, wherein the obtaining of the synchronization signal by the power supply comprises:

when a synchronous acquisition instruction input by a user is received, acquiring the synchronous signal from the power supply;

alternatively, the first and second liquid crystal display panels may be,

and when detecting that the current time and/or the current environmental parameters meet a preset trigger condition, acquiring the synchronous signal from the power supply.