WO2022048465A1

WO2022048465A1 - Camera exposure time adjustment method, device and program product

Info

Publication number: WO2022048465A1
Application number: PCT/CN2021/113951
Authority: WO
Inventors: 程敏; 卓峰; 黄进新; 方光祥
Original assignee: 华为技术有限公司
Priority date: 2020-09-04
Filing date: 2021-08-23
Publication date: 2022-03-10
Also published as: CN114143470A

Abstract

A camera exposure time adjustment technique, comprising: for multiple cameras that are located in the same scene, when the interference of a light-supplementing lamp of a primary camera on the exposure of a secondary camera causes shading unevenness or flickering in a video image, the brightness of two adjacent black-and-white image frames generated by the secondary camera is compared, and the exposure time of the secondary camera is adjusted according to the comparison result, so that each fill-supplementing duration is located within a single light-supplementing period of the secondary camera, thus reducing the flickering of the video image captured by the secondary camera.

Description

Method, device and program product for adjusting camera exposure time

technical field

The invention relates to the field of cameras, in particular to a technology for adjusting the exposure time of cameras.

Background technique

The ambient light intensity at night is much lower than during the day. The image captured by the camera in low light conditions becomes blurred, so that the recognition rate of the image drops sharply. In order to allow the camera to shoot high-definition color images at night, a common practice is to use a fill light to provide additional lighting to the camera when the camera shoots video to improve the image shooting effect.

One camera solution is to use a single sensor and single lens architecture, and to generate visible light signals and infrared light signals respectively by time-multiplexing the sensors, and then register and fuse the visible light signals and infrared light signals in the time domain. This solution is not only low cost, but also easy to manufacture on a large scale.

It is this time-sharing fill light scheme that also faces a problem. When there are multiple cameras in the same scene, the fill light of a certain camera will interfere with the imaging of other surrounding cameras. For example, when camera A is exposing black and white frames line by line, camera B near camera A is using an infrared fill light for fill light, and the image captured by camera A is affected by the fill light of camera B, resulting in camera A The captured frame has uneven brightness and darkness.

SUMMARY OF THE INVENTION

In a first aspect, the present invention provides an embodiment of a method for adjusting the exposure time of a camera, which is used to adjust the exposure time of a first camera, wherein: each shooting cycle of the first camera includes at least 3 frames, so The 3 frames include color frames and black and white frames, and the first camera receives periodic fill light from the environment when shooting, and each fill light time period in the periodic fill light is shorter than that of the first camera. Filling light period, the method includes: comparing the brightness of two adjacent frames of the same type in the same shooting period of the first camera, wherein the frames of the same type refer to black and white frames or color frames. ; Adjust the exposure start time of the subsequent frames of the first camera according to the comparison result, until each adjusted light-filling time period is within a single fill-light period of the first camera.

Using this method, the exposure time of the first camera can be adjusted. Before the adjustment, the periodic fill light from the environment (for example, the periodic fill light from the second camera) has different effects on the upper and lower parts of the same frame, so that the As for frames that appear half-light and half-dark. After adjustment, each of the fill light time periods is within a single fill light period of the first camera, and different parts of the frame are equally affected by the periodic fill light during the exposure process, reducing the image captured by the first camera. Uneven light and dark conditions.

In a first possible implementation manner of the first aspect, the first camera includes: a lens for collecting light including the periodic supplementary light; a sensor for collecting light at different times according to the light collected by the lens The color frame and the black and white frame are generated.

This scheme introduces the hardware structure of the first camera. The sensor used in this scheme can sense both visible light to generate color frames and non-visible light (such as infrared light) to generate black and white frames. Color frames and black and white frames are generated at different times.

In the second possible implementation manner of the first aspect, the periodic fill light is non-visible light, each of the adjusted fill light time periods corresponds to a black and white frame, and each of the fill light time periods is located in a corresponding black and white frame. in the fill light cycle.

In this scheme, it is specified that the black and white frames are affected by the periodic fill light in the environment.

In a third possible implementation manner of the first aspect, the total number of frames in the shooting period of the first camera is 3 frames, wherein the 3 frames include: 1 black and white frame and 2 consecutive color frames, or, 1 color frame and 2 consecutive black and white frames.

This scheme limits the number of frames in the frame period to 3 frames, and 2 frames of the same type are consecutive. Using adjacent frames of the same type makes it easier to compare brightness.

In a fourth possible implementation manner of the first aspect, the black and white frame and the color frame have the same exposure period.

In a fifth possible implementation manner of the first aspect, the periodic fill light comes from a fill light of the second camera.

This protocol introduces a common source of periodic fill light.

In a sixth possible implementation manner of the first aspect, the periodic fill light comes from a fill light of the second camera, and the second camera and the first camera are located in the same shooting environment, and the first camera and the first camera are located in the same shooting environment. The shooting cycle of a camera is the same, and the fill light rule is the same.

This scheme describes the commonality of the first camera and the second camera.

In the seventh possible implementation manner of the first aspect, the shooting period includes a plurality of black and white frames, the supplementary light period includes a plurality of supplementary light time periods, and the number of supplementary light time periods is the same as that in the shooting period. The number of black and white frames included is the same.

Optionally, the supplementary light intensity of each supplementary light time period is also the same.

In this scheme, each black and white frame will be affected by the periodic fill light in the environment, so the brightness of the two black and white frames before and after is similar. Reduced the flickering phenomenon caused by the large difference between the two brightnesses in the front and rear videos.

In the eighth possible implementation manner of the first aspect, when the brightness change in the two adjacent frames of the same type satisfies that the brightness of the pixel strip below the previous frame is greater than the brightness of the pixel strip below the subsequent frame, the The phase difference of the shooting period of the first camera and the second camera is Δφ=φ ₁ +2n*π, -φ _{frame period} <φ ₁ <0°, n is an integer, and the phase difference Δφ is used to adjust the Parameter of exposure start time of subsequent frames of the first camera.

This solution exemplarily introduces a specific algorithm for comparing brightness. The front frame and the back frame here are 2 frames generated by the camera at different times. The front frame is generated first, and the latter frame is generated later.

In a second aspect, the present invention provides an embodiment of a camera, the camera includes a lens for collecting light, the light received by the lens includes periodic supplementary light from the environment, each of the periodic supplementary light The fill light time period is shorter than the fill light period of the camera; the sensor is used to convert the light signal collected by the lens into an electrical signal, and each shooting period generates at least 3 frames, and the 3 frames include color frames and black and white frames. frame; a processor for: comparing the brightness of two adjacent frames of the same type in the same shooting period, wherein the frames of the same type are black and white frames, or color frames; adjusting the brightness of the subsequent frames of the camera according to the comparison result The exposure start time, until each adjusted fill-light time period is within a single fill-light period of the camera.

This solution is similar to the first aspect and has similar technical effects.

Corresponding to various possible implementations of the first aspect, the second aspect also supports corresponding possible implementations and has corresponding technical effects.

In a third aspect, the present invention provides an exposure time adjustment device for adjusting the exposure time of a first camera, wherein: each shooting cycle of the first camera includes at least 3 frames, and the 3 frames Including color frames and black and white frames, the first camera receives periodic fill light from the environment when shooting, and each fill light time period in the periodic fill light is shorter than the fill light period of the first camera, It is characterized in that, the device includes: a brightness comparison module for comparing the brightness of two adjacent frames of the same type in the same shooting period of the first camera, wherein the frames of the same type refer to black and white frames. , or the type is color frame; the adjustment module is used to adjust the exposure start time of the subsequent frames of the first camera according to the comparison result, until each of the adjusted fill light time periods is located in a single complement of the first camera. within the photoperiod.

This solution is similar to the first aspect and has similar technical effects.

Corresponding to various possible implementations of the first aspect, the third aspect also supports corresponding possible implementations and has corresponding technical effects.

In a fourth aspect, the present invention also provides an embodiment of a program product, the program product includes computer-readable code instructions, when the computer-readable code instructions are executed by the first camera, the first camera can execute the first camera. aspects and various possible implementations of the first aspect. And have the corresponding technical effect.

Description of drawings

Figure 1 shows an embodiment of a camera topology.

FIG. 2 illustrates an embodiment of the exposure sequence of frames to the present invention.

Figure 3 shows a frame with uneven exposure.

Figure 4A shows a frame with uneven exposure.

Figure 4B shows a uniformly exposed frame.

Figure 5 shows the relationship between the exposure timing of the frames captured by the two cameras.

Figure 6 shows the relationship between the exposure timing of the frames captured by the two cameras.

Figure 7 shows the relationship between the exposure timing of the frames captured by the two cameras.

Figure 8 shows the relationship between the exposure timing of the frames captured by the two cameras.

FIG. 9 exemplarily describes the brightness relationship of the previous frame relative to the subsequent frame in the above four strategies.

FIG. 10 is an alternative embodiment of an exposure time adjustment method.

Figure 11 is an alternative embodiment of an exposure time adjustment device.

detailed description

The embodiment of the present invention is used to adjust the exposure time of the camera. For example, in a scene, there are more than two cameras for continuous shooting. These cameras each fill light for the frames they shoot during shooting. In addition to the convenience of shooting, it may also affect other cameras in the cycle. This effect is often unfavorable, such as causing uneven brightness of the frames. The present invention can adjust the exposure time of one or more cameras to reduce the visual deterioration of the frames generated by the cameras caused by this effect. These two or more cameras can have: the same shooting period, the number of frames shot in each shooting period is the same; the sequence of the types of frames shot in each shooting period is also the same, for example, in each frame period, one is shot first Color frames, and then shoot 2 black and white frames in succession; the same fill light rule, for example: fill light for each black and white frame shot by itself, and the fill light time for each black and white frame is the same.

As shown in FIG. 1 , the camera 11 includes a lens 111 , a sensor 112 , a system on chip (SOC) 113 , and a fill light 114 . Depending on the design, the fill light 12 may be a part of the camera; the fill light 12 may also be independent of the camera, and thus may not be part of the camera.

The lens 111 is used to collect the light from the photographed object. The lens 111 is usually a lens group composed of multiple pieces of optical glass (or plastic), and may be composed of a concave lens, a convex lens, an M-type lens, etc., or a combination of lenses. The lens 111 can be a spherical mirror or an aspherical mirror. The camera 11 in FIG. 1 has only one lens, so it is called a monocular camera.

The sensor 112 receives light from the lens, performs photoelectric conversion through exposure, and generates a black and white frame (grayscale frame) and a color frame (color frame). Black and white frames may also be referred to as grayscale images or grayscale frames; color frames may also be referred to as color images. Inside the sensor is control logic that alternately exposes visible and non-visible light (such as infrared light), so that a single sensor can alternately generate black-and-white and color frames. Taking the video frame rate of 25 frames/second as an example, the total exposure time required to obtain a black and white frame and a color frame is 1/25 of a second. The average exposure time for a frame is 1/50 of a second. As a result, black and white frames and color frames are continuously generated. Black and white frames can provide brightness information, and visible light frames can provide color information and brightness information. When the number of sensors possessed by the camera 11 is one, the camera 11 is also called a single-sensor camera. Optionally, there may also be a filter (not shown) between the lens and the sensor.

The system-on-chip 113 is an integrated circuit chip. The system-on-chip 113 may integrate an image signal processor (ISP), a digital signal processor, a CPU, an encoder, and the like. The digital signal processor camera amplifies and corrects the electrical signal; the ISP has the ability to optimize the frame; the CPU (such as

The processor) can fuse black and white frames and color frames to generate a fusion image, and can also control the fill light 114, such as adjusting the fill light start time and cut-off time of the fill light through an exposure control circuit (not shown); coding; The device is used to encode the frames processed by the CPU with protocols such as JPEG, H.264, and H.265, so as to facilitate the transmission and preservation of the frames. In other embodiments, one or more of the ISP, digital signal processor, CPU, and encoder may be separate physical modules, not integrated in the SOC.

The fill light 114 is used to provide fill light for the object being photographed. For example, when the sensor 112 exposes infrared light, the fill light 114 performs infrared light fill light, thereby improving the imaging effect of the black and white frame. The fill light 114 may be a part of the camera 11 , or may be an external device not belonging to the camera 11 .

The concepts involved in the embodiments of the present invention are explained below.

Ambient fill light: In addition to the built-in/external fill light of the camera, the fill light that occurs in the environment where the camera is located. This fill light may have a fixed periodicity. For example: periodic supplementary light from other cameras in the environment where the camera is located, periodic lights on and off, periodic flashing alarm lights, etc.

Exposure period: The time it takes for the camera's sensor to capture a single frame.

Shooting cycle: The sensor of the camera shoots cyclically with multiple frames as a cycle, such as 2 black and white frames + 2 color frames as a cycle to shoot repeatedly, or 1 color frame + 2 black and white frames as a cycle, each The time required for a loop is one shooting cycle. Frames within the same capture cycle can be fused to generate color frames. For example, fuse 2 black and white frames with 1 color frame in the same cycle to generate 2 color frames; fuse 2 black and white frames with 2 color frames in the same cycle to generate 2 color frames.

Pixel strip: A frame consists of multiple rows of pixels, and a row (or multiple rows) of pixels of a frame is called a pixel strip. For sensors that expose pixel-by-pixel strips (eg, row-by-line exposure sensors), a pixel strip is a single exposure unit. The initial exposure time of each pixel strip is different, and the sensor first exposes the pixel strip located above, and then exposes the pixel strip located below.

Fill light period: used to describe the length of the time period during which all pixel strips are in the exposed state. For example: the time it takes from the exposure of the bottom pixel bar of a frame to the end of the exposure of the top pixel bar of this frame.

During the generation of a frame by a sensor (eg, a progressive exposure sensor) from exposure, exposure of the entire frame is not initiated at the same time. Rather, it is exposed gradually in a certain order. Specifically, the top of the frame is first generated by exposure, and then gradually exposed downward until the bottom of the final frame is generated, and the exposure of the entire frame is completed. In other embodiments, the bottom pixel bar of the frame may be generated by exposure first, and then gradually exposed upward until the top pixel bar of the frame is generated by exposure.

Suppose there is a first camera and a second camera in the same environment. The first fill light of the first camera generates the first fill light; the second fill light of the second camera generates the second fill light, and the first camera generates the frame P through exposure.

If the fill light time period of the second fill light is inconsistent with the fill light time period of the first fill light, the exposure of the frame P may be disturbed by the second fill light. Figure 2 describes the exposure process of frame P. Frame P consists of 8 pixel strips from P1 to P8, with P1 at the top and P8 at the bottom. Each pixel strip is a row of pixels (if the sensor can If multiple rows of pixels are exposed at the same time, each pixel bar can be multiple rows of pixels).

The effects of the first supplementary light and the second supplementary light on the exposure process of the frame P are marked with hatched parts in FIG. 2 . At time A1, the first camera starts to expose P1 (A1 is also the exposure start time of frame P), and at time A2, the first camera starts to expose P2... and time A5 is the time when the exposure of P1 ends, A8 The time is the time at which the exposure of P8 ends (and also the time at which the exposure of frame P ends). The duration of the first supplementary light and the duration of the second supplementary light may be the same. The time period A1-A5 is the exposure time period of the pixel bar P1, the time period A1-A8 is the exposure period of the first camera, and the time period A9-A5 is the fill light period of the first camera.

The brightness of the frame is affected by the exposure level when the sensor generates the frame, and the exposure level is determined by the amount of light entering the sensor. The more light that comes in, the more photons are converted into electrons and the brighter the resulting frame. The amount of incoming light is determined by both the light intensity and the light duration. Each row of the sensor corresponds to a row of pixels in frame P, and the sensor performs exposure row by row. Rows with a large amount of light input produce relatively bright pixel bars; rows with less light input produce relatively dim pixel bars. During the exposure process of frame P, the amount of incoming light includes three sources: the first supplementary light, the second supplementary light, and other light in the environment other than the first supplementary light and the second supplementary light (eg, natural light in the environment). Since the impact of natural light on different pixel strips is the same, it will not cause problems such as video flickering. For the convenience of description, in the embodiment of the present invention, the influence of natural light on exposure is not introduced separately unless otherwise specified. Similarly, since the fill light of the first camera is controlled by the first camera, the fill light period of the first camera can be easily synchronized with the fill light period of the camera.

The following introduces the problem caused by the non-synchronization of the fill light period of the first camera and the fill light period of the second camera.

In the frame P of FIG. 2, since the start and end time points (A3, A4) of the first fill light span across P1, P2, P3, P4, P5, P6, P7 and P8, the exposures of P1-P8 will be affected by The effect of the first fill light. From the time point A6, the second fill light affects the exposure of the frame, and until A7, the effect of the second fill light on the frame P ends. When the second fill light is exerting its influence, P1-P2 has already been exposed, so P1 and P2 will not be affected by the second fill light; while P3-P8 are in the process of being exposed, so P3-P8 will be affected by the second fill light. effect of light. That is to say, P1-P2 are only affected by the first supplementary light; while P3-P8 are affected by both the first supplementary light and the second supplementary light. Therefore, the exposure amounts of different pixel strips are not the same, which will cause uneven brightness in the exposed frame P.

The exposure of P1 and P2 is not affected by the second fill light. P3-P6 are partially affected by the second supplementary light, wherein: the overlapping part of P3 and the second supplementary light is 201, the overlapping part of P4 and the second supplementary light is 202, and the area of the area 202 is larger than the area of the area 201. Therefore, The influence of the second fill light on the exposure of P4 is greater than that of the second fill light on the exposure of P3; similarly, the exposure of P5 and P6 is gradually increased by the influence of the second fill light. However, P7 and P8 are more affected by the second supplementary light than P5 and P6. Therefore, the frame P as a whole presents the effect of "upper dark and lower bright". The upper pixel bars (P1-P2) are relatively dark, the pixel bars (P3-P6) below P2 gradually increase in brightness, and the lowest pixel bars (P7, P8) have the highest brightness. Figure 3 is an example frame of "upper dark and lower bright" due to uneven fill light. It can be seen from the picture that the lower body of the pedestrian in the photo is brighter, while the upper body is very dark and can hardly be seen clearly.

The frame of Fig. 4A is opposite to that of Fig. 3. The pedestrians appearing in the frame show the visual effect of "light on the top and dark on the bottom", the upper body is brighter, and the legs are too dark to be seen clearly. The reason for the generation of Fig. 4A is: the part above the frame is not only affected by natural light, but also affected by 2 fill lights (the first fill light and the second fill light) during exposure, and the sensor obtains the total input The amount of light is relatively large; while the lower part of the frame is only affected by natural light during exposure, and is only affected by one fill light (the first fill light), and the amount of light entering the sensor is relatively small.

FIG. 4B is the adjacent previous frame of FIG. 4A , and each pixel strip of the frame is illuminated the same, so the light and shade of FIG. 4B are visually uniform. In the video, when the “uneven-uniform” change as shown in FIG. 4B and FIG. 4A appears repeatedly in the video, a “flickering” effect will appear visually, causing discomfort to the user. When camera A is exposing a color image and camera B is filling in infrared light, the video (full or partial) generated by camera A will flicker or color cast.

It can be seen from this that, for the sensor exposed pixel by pixel, when the fill light from the outside (or other periodic fill light from the environment) is inconsistent with the fill light period of the camera: the camera will The generated single-frame image is half-bright and half-dark; it will also cause a large difference in the brightness and darkness of adjacent images, resulting in a flickering phenomenon in the video. Both of these effects are unfavorable to the shooting of this camcorder and belong to the "interference" to this camcorder.

In the embodiment of the present invention, the exposure start time of the subsequent frames of the first camera is adjusted by comparing the brightness of adjacent frames captured by the camera. For example: Adjust the exposure time of the camera (or the fill light time and the exposure time according to the law that the frame exposure process is disturbed by the periodic supplementary light from the non-camera in the environment (such as the supplementary light of the non-camera). time), so that during the exposure process of the camera, all the pixel strips of the same frame are affected by the same periodic fill light (or all the same pixel strips are not affected by the ambient fill light), thus Achieves uniform brightness throughout the frame. In the exposure period of the same frame, different pixel strips are not affected by the ambient fill light inconsistently, so that a "half-light and half-dark" frame appears; it also avoids the flickering phenomenon caused by the difference in brightness between the front and rear frames.

The adjacent frames here are frames of the same type, for example, two adjacent black and white frames, or two adjacent color frames. It should be noted that, in this embodiment of the present invention, what is concerned is whether the exposure of the camera is disturbed by the ambient supplementary light, and the supplementary light of the camera itself may not be considered, that is to say, the first camera turns on the supplementary light or turns off the supplementary light. None of the lights affect the implementation of embodiments of the present invention. The supplementary light in the environment is periodic, and can come from other cameras different from the first camera, or from other periodic lighting devices.

Specifically, the embodiments of the present invention compare the brightness of the same position in two adjacent frames of the same camera. For example, compare the average brightness of the uppermost pixel strip of the previous frame with the brightness of the uppermost pixel strip of the second frame; The average luminance value of the top three pixel bars is compared; alternatively, the average luminance value (eg arithmetic mean) of the lower 1/5 part of the previous frame is compared with the average luminance value of the lower 1/5 of the following frame. The camera can periodically compare the brightness values, or start the brightness value comparison in the camera administrator's control box.

Referring to FIG. 5 , there are a first camera and a second camera in the same area, both of which are single-sensor cameras, both of which can generate both color frames and black and white frames. The exposure time for black and white frames and color frames is the same, and this exposure time is called the exposure period. In addition, both cameras shoot in a period of three frames, which is called a shot period. Included in each shooting cycle: 1 color frame and 2 black and white frames. The second camera exposure generates

frames

210, 211, 212, 213 and 214, wherein

frames

210 and 213 are color frames, frames 211 and 212 are black and white frames, and the black and white frames use fill light during the exposure process . The first camera exposure generates frame 215, frame 216, frame 217, frame 218 and frame 219, wherein frame 215 and frame 218 are color frames, frame 216, frame 217 and frame 219 are black and white frames, and black and white frames are used in the process of exposure fill light. Frame 210 corresponds to frame 215 , frame 211 corresponds to frame 216 , and frame 212 corresponds to frame 217 . According to the sequence relationship of the frames, the frame 215 is generated before the frame 216 , so the frame 215 is the frame before the frame 216 , and the frame 216 is the frame after the frame 215 .

It should be noted that this embodiment is described by taking an example of using an infrared fill light to fill light for a black and white frame. In addition to fill light for black and white frames, it can also fill light with visible light during exposure of color frames, and can also fill light with infrared fill lights during exposure of color frames. Whether to use fill lights during exposure of color frames , does not affect the implementation of the embodiments of the present invention.

Table 1 below describes the operation of the cameras shown in Figure 5 at different time periods.

时间段period	摄像机运行功能Camera operation function
t1-t8t1-t8	帧216曝光(曝光周期)Frame 216 exposures (exposure period)
t2-t4t2-t4	第二摄像机补光(补光3)The second camera fill light (fill light 3)
t3-t5t3-t5	第一摄像机补光(补光1)The first camera fill light (fill light 1)
t6-t12t6-t12	帧217曝光(曝光周期)Frame 217 exposure (exposure period)
t7-t10t7-t10	第二摄像机补光(补光4)The second camera fill light (fill light 4)
t9-t11t9-t11	第一摄像机补光(补光2)The first camera fill light (fill light 2)
t13-t14t13-t14	第一摄像机曝光滞后于第二摄像机的时间差The time difference between the exposure of the first camera and the lag of the second camera

Table 1

Combining Figure 5 and Table 1, right: when the first camera lags behind the exposure of the second camera, and the time length of the lag is less than one exposure period (that is, the time period [t2, t8] > the time period [t13, t14]) In the case of exposure, the characteristics of the resulting frame are introduced.

The exposure of frame 216 is as follows.

(1) During the time period from t3 to t5, the fill light 1 of the first camera has an impact on the exposure of the frame 216, and all the pixel bars of the frame 216 have the same impact.

(2) During the time period from t2 to t4, the fill light 3 will affect the exposure of the pixel strips of the frame 216. Among them, the pixel strips located above the frame 216 are more affected than the pixel strips located below the pixel strip 216 .

(3) At time t7, the fill light 4 of the second camera starts to work. At this time, the pixel bar above the frame 216 has been exposed, so it will not be affected by the fill light 4. The lower pixel bar of the frame 216 is still in the process of exposure, so it will be affected by the fill light 4 . Therefore, the frame 216 after the exposure is completed will exhibit a feature of being dark on the top and bright on the bottom, similar to the situation in FIG. 3 .

During the exposure of the frame 217 by the first camera, in addition to receiving the supplementary light 2 from the first camera, the supplementary light 4 is also affected by the second camera. The frame 217 after exposure is completed will show the characteristics of upper light and lower dark.

In FIG. 5 , the luminance value of the lower pixel bar in frame 216 after exposure is completed is higher than the luminance value of the lower pixel bar in frame 217 . Here is a comparison between the pixel strip at the bottom of frame 216 and the pixel strip at the bottom of frame 217 as an example: the formation of the pixel strip at the bottom of frame 216 is affected by three fill lights, which are: t3-t4 time period The fill light 3, the complete fill light 1 (t3-t5 time period), the fill light 4 of the t7-t8 time period. The formation of the pixel bar at the bottom of the frame 217 is affected by a total of 2 fill lights, namely: fill light 4 in the time period t9-t10, and complete fill light 2 (time period t9-t11). The total duration of the former affected by the fill light during the exposure process is greater than that of the latter, so the brightness value of the pixels obtained by exposure is higher, that is, the brightness of the pixel bar at the bottom of frame 216 is greater than that of the pixel bar at the bottom of frame 217.

In the scene with 3 frames as one cycle described in Figure 5, although Figure 5 only shows a specific example, according to repeated experimental verification and statistics, it can be found that as long as the exposure of the first camera to the frame lags behind the first camera The exposure of the frame by the two cameras, and the degree of lag is less than one exposure period, will conform to the conclusion that the brightness of the pixel bar below the front frame of the first camera is higher than the brightness of the pixel bar below the back frame. That is, when these two frames are played, there is a visual flickering phenomenon. And after repeated verification, this conclusion is also true in reverse, that is: when the adjacent frames of the same type of the first camera (for example, two adjacent color frames, or two adjacent black and white frames), the lower part of the previous frame is The brightness of the pixel bar is higher than the brightness of the pixel bar below the back frame. Therefore, a first adjustment strategy can be obtained: the exposure of the frame by the first camera has a phase lag compared with the exposure of the frame by the second camera, and the lag phase is less than the phase of one frame.

Considering that the first and second cameras both use 3 frames as a shooting cycle, color frames and black and white frames will appear repeatedly. Shortly after the second camera starts exposing the color frame, the second camera starts exposing the color frame, and the time difference between the two exposure times is less than one exposure period. That is to say, the first camera lags behind the shooting of the same type of frames by the second camera, if the difference between the frames shot by the first and second cameras is described in the coordinate system with time as the axis. Two periodic waveforms are formed, and there is a phase difference between the two waveforms. This phase difference is named Δφ, that is, Δφ = the phase of the first camera - the phase of the second camera, then Δφ = φ ₁ +2n*π, where -φ _{frame period} <φ ₁ <0°, φ _{frame Period} is the phase corresponding to one exposure period. The symbol "-" in the -φ _{frame period} indicates that the phase of the first camera lags behind the phase of the second camera. Since the phase is periodic, "lag" and "advance" in various embodiments of the present invention are relative concepts. For example: the shooting period of the first camera lags behind the shooting period of the second camera, and the delayed phase difference value is φ ₁ ; The phase difference value of is φ ₁ +2π.

Example: When the shooting period of the first camera has a total of 3 frames, and the exposure time of each frame is the same, the phase corresponding to the exposure period of each exposure period is 360°/3=120°; then -120°＜φ ₁ ＜ 0°; thus, Δφ=φ ₁ +2n*π. By adjusting the exposure time of the first camera according to φ ₁ +2n*π, it can be synchronized with the shooting cycle of the second camera. For example, the exposure start time of the subsequent frames of the first camera can be advanced. To describe, it is equivalent to adjusting the phase of the exposure period of the first camera by φ ₁ .

It should be noted that it is not necessary to keep the exposure time of the first camera and the second camera exactly the same, as long as each fill light period of the second camera is within a single fill light period of the first camera. . Therefore the actually adjusted phase may not be a fixed value but a phase range. Since Δφ gives the direction of adjustment and the range of adjustment, the adjustment can be completed quickly after obtaining Δφ.

When the exposure start time of the first camera to the black and white frame is advanced, the phase of the first camera can be adjusted forward appropriately, and the difference between the start time of the fill light between the first camera and the second camera can be reduced, so that: Light 3 has the same impact on the exposure of all pixel strips in the black and white frame 216, and makes the fill light 4 have the same impact on the exposure of all pixel strips in the black and white frame 217, so that the fill light of the second camera is achieved in advance to achieve the same exposure of the two . For example: Suppose the exposure period of the first camera is 200ms, and the shooting period is 600ms; the exposure time of the first camera to the color frame is 40ms later than that of the second camera, then the exposure time of the first camera The exposure time is advanced by 40ms+n*600ms, where n is any integer including 0. Since the first camera adjusts its own exposure time based on the fill light time of the second camera, it can be considered that there is a master-slave relationship between the two. The second camera is the master camera and the first camera is the slave camera.

It should be noted that the above adjustment may not be in place at one time. If the first adjustment fails to achieve the purpose, the adjustment can be repeated until the black and white frame captured does not appear "half-bright and half-dark", and the adjustment range is always within △φ. within. For example: -120°＜△φ＜0°, the exposure period is 200ms, and △φ is a negative value, so the adjustment direction is to advance the exposure time of the first camera, and advance the exposure time by 10ms for each adjustment. After each adjustment, if the black and white frames obtained by the first camera still have uneven brightness, advance the exposure time by 10ms again. After multiple adjustments, the brightness of the black and white frames collected by the first camera can be uniform. 200ms/10ms=20, so the total adjustment times will not exceed 20 times; if each adjustment is 20ms, the total adjustment times will not exceed 200ms/10ms, that is, 10 times.

In this embodiment, the fill light time periods of the first camera and the second camera may be the same, that is: fill light time period 1 = fill light time period 2 = fill light time period 3 = fill light time period 4 .

The above conclusions can be summarized as the first Δφ calculation method: when the adjacent frames of the same type of the first camera (for example, two adjacent color frames, or two adjacent black and white frames), the pixel bar below the previous frame is The brightness of the frame is higher than the brightness of the pixel bar below the subsequent frame, then: there is a phase lag between the waveform of the frame generated by the exposure of the first camera and the waveform of the frame generated by the exposure of the second camera, and the lag phase is less than the phase of one frame, That is, the formula Δφ=φ ₁ +2n*π exposure period. Adjust the exposure start time of the first camera to the subsequent frames according to Δφ, advance the exposure start time of the first camera to the subsequent frames, and the advance time does not exceed the exposure period of one black and white frame, which can realize the Each fill light time period is within the fill light period of the first camera.

The derivation process of the first adjustment strategy is described in detail above. The second adjustment strategy, the third adjustment strategy and the fourth adjustment strategy will be introduced below. Since the derivation process and principle are similar to the first adjustment strategy, for the purpose of saving space, no detailed description will be given.

FIG. 6 is another schematic diagram for describing the exposure timing of the first and second cameras, and is used for introducing the second adjustment strategy. The content of FIG. 6 is similar to that of FIG. 5 , the difference is that the exposure time of the first camera is earlier than that of the second camera. The advance time is less than one exposure period, that is: time period [t15, t16] < time period [t17, t18].

It can be seen that the upper pixel bar in frame 216 is affected by fill light 1 and fill light 3; while the pixel bar above frame 217 is affected by fill light 2, fill light 3 and fill light 4. Among them: the effect of the fill light 1 on the frame 216 is the same as the effect of the fill light 2 on the frame 217, and the light input of the fill light 3 to the sensor is less than the light input of the pixel bar above when the fill light sensor exposes the frame 217. When the sensor exposes the frame 216, the amount of light entering the upper pixel bar (for a detailed analysis, refer to the description of FIG. 3 and FIG. 5 above), so the brightness of the pixel bar above the frame 216 is greater than that of the frame 217.

The above conclusion can be summarized as the second Δφ calculation method: when the adjacent frames of the same type of the first camera (for example, two adjacent color frames, or two adjacent black and white frames), the pixel bar above the previous frame is is greater than the brightness of the pixel bar above the back frame. Then: there is a phase lag between the frame generated by the first camera and the frame generated by the second camera, and the lag phase is less than the phase of one frame, that is, the formula Δφ=φ ₂ +2n*π, where 0° <φ2<φ _{frame period} exposure period.

FIG. 7 is another schematic diagram for introducing the exposure timing of the first and second cameras, and is used for introducing the third adjustment strategy. The content of FIG. 7 is similar to that of FIG. 5 , the difference is that: comparing the exposure time points of frame 210 and frame 215 (frame 215 corresponds to 210 ), the exposure time of the first camera is earlier than that of the second camera. The length of time in advance is greater than one exposure period and less than 1.5 exposure periods (due to the periodicity of exposure, you can also choose to use the exposure time points of frame 220 and frame 215 for corresponding comparison, then the exposure of the first camera is delayed after the second camera. , the delay time length is: more than one exposure period, less than 1.5 exposure periods). That is: time period [t25, t26] < time period [t23, t24] < 1.5* time period [t25, t26].

In frame 216, the upper pixel strip is affected by fill light 1 and fill light 5; in frame 217, the upper pixel strip is affected by fill light 2 and fill light 3; and, fill light 5 affects frame 216. The duration is longer than the duration of the effect of fill light 3 on frame 217. Therefore, it can be concluded that (1) the brightness of the pixel strip above the frame 216 is greater than the brightness of the pixel strip above the frame 217 . The pixel bar below the frame 216 is affected by the fill light 5 and the fill light 1; the pixel bar below the frame 217 is affected by the fill light 2 and the fill light 3; and the effect of the fill light 5 on the frame 216 is longer than the fill light 3 pair. The duration of the influence of frame 217, it can therefore be concluded that (2) the brightness of the pixel strip below frame 216 is less than the brightness of the pixel strip below frame 217. In addition, the pixel bars corresponding to frame 216 and frame 217 are used for comparison (eg, the first row of pixel bars of frame 216 is compared with the first row of pixel bars of frame 217, eg, the second row of pixel bars of frame 216 is compared with the first row of pixel bars of frame 217. Comparison of two rows of pixel bars), it can be concluded that (3) the pixel bars of frame 216 that are brighter than frame 217 are located above frame 216, the pixel bars of frame 216 that are darker than frame 217 are located below frame 216, and frame 216 is lighter than frame 216. The brighter pixel bars of frame 217 are a minority of the total pixel bars of frame 216 .

The above rules can be summarized as the third △φ calculation method: when the adjacent frames of the same type of the first camera (such as two adjacent color frames, or two adjacent black and white frames): the pixel bar above the previous frame. The brightness of the pixel strip above the next frame is greater than the brightness of the pixel strip above the next frame; and the brightness of the pixel strip below the previous frame is less than the brightness of the pixel strip below the subsequent frame; and, the number of pixel strips in the previous frame higher than the brightness of the subsequent frame < The previous frame is lower than the subsequent frame. The number of pixel bars of brightness, then: the frame generated by the first camera has a phase advance compared with the frame generated by the second camera, and the value of the advanced phase is between the phase of one exposure period and the phase of 1.5 exposure periods, and also It is the formula Δφ=φ ₃ +2n*π, where φ _{frame period} <φ2<1.5*φ _{frame period} exposure period exposure period.

FIG. 8 is another schematic diagram for introducing the exposure timing of the first and second cameras, and is used for introducing the fourth adjustment strategy. The content of FIG. 8 is similar to that of FIG. 5 , the difference is that: comparing the exposure time points of frame 210 and frame 215 , the exposure time of the first camera lags behind that of the second camera. The time length of the lag is greater than one exposure period and less than 1.5 exposure periods. That is: time period [t29, t30] < time period [t27, t28] < 1.5* time period [t29, t30].

The upper pixel strip in frame 216 is affected by fill light 1 and fill light 4; the pixel strip above frame 217 is only affected by fill light 2, so it can be concluded that: (1) the brightness of the pixel strip above frame 216 is greater than that of frame 216 The brightness of the pixel bar above 217. The pixel bar below frame 216 is only affected by fill light 1 and fill light 4, while the pixel bar below frame 217 is jointly affected by fill light 2 and fill light 6. The length of time that fill light 4 illuminates the pixel bar below frame 216 is less than The length of time that the fill light 6 illuminates the pixel bar below the frame 217 , so it can be concluded that (2) the brightness of the pixel bar below the frame 216 is smaller than that of the pixel bar below the frame 217 . In addition, comparing the pixel bars corresponding to frame 216 and frame 217, it can be concluded that (3) the pixel bars in frame 216 that are brighter than frame 217 are located above frame 216, and the pixel bars in frame 216 that are darker than frame 217 are located at the top of frame 216. Below frame 216, and where frame 216 is brighter than frame 217, constitutes the majority of frame 216's total pixel bars.

The above conclusion can be summarized as the fourth △φ calculation method: when the adjacent frames of the same type of the first camera (for example, two adjacent color frames, or two adjacent black and white frames): the pixel bar above the previous frame. The brightness of the pixel strip above the next frame is greater than the brightness of the pixel strip above the next frame; and the brightness of the pixel strip below the previous frame is less than the brightness of the pixel strip below the post frame; and, the number of pixel strips in the previous frame that is higher than the brightness of the latter frame> the previous frame is lower than the latter frame. The number of pixel bars of brightness, then: there is a phase lag between the frame generated by the first camera and the frame generated by the second camera, and the value of the lag phase is between the phase of one exposure cycle and the phase of 1.5 exposure cycles, also It is the formula Δφ=φ ₄ +2n*π. -1.5*φ _{frame period} <φ ₄ <-φ _{frame period} .

Table 2 summarizes the correspondence between the above-mentioned brightness changes of adjacent frames and the phase difference Δφ of the first camera relative to the second camera. After obtaining Δφ according to the brightness variation law, the corresponding phase adjustment can be performed. It should be noted that these four situations are independent of each other and have no dependencies on each other, so for a specific camera, the exposure time can be adjusted based on only one of the formulas.

Table 2

In addition, these four formulas are exemplified by taking 3 frames as a shooting cycle in the embodiment described in FIG. 5-FIG. 8, when the shooting cycle includes more frames (for example, 2 consecutive color frames + 2 consecutive black and white frames) ), the above four formulas for calculating Δφ are still valid.

In order to facilitate the understanding of Table 2, FIG. 9 is used to exemplarily describe the brightness relationship between the previous frame and the subsequent frame in the above four strategies. Frame 31 is an example of frame 216 in the first adjustment strategy; frame 32 is an example of frame 216 in the first adjustment strategy; frame 33 is an example of frame 216 in the first adjustment strategy, where h <i; frame 34 is an example of frame 216 in the first adjustment strategy, where j>k.

In the above-described embodiments, the introduction is made based on the detection of the black and white frames affected by the fill light when adjacent frames of the same type are used. In fact, the brightness of the color frame is also affected by the infrared fill light/visible light fill light in the environment during exposure, so when the exposure period of the color frame is not synchronized with the ambient fill light, there will also be semi-brightness and semi-darkness. The method provided by the embodiment of the present invention is also applicable to the exposure time adjustment based on color frames. By comparing the brightness of the two color frames before and after, the law of the phase difference can also be judged, so that the exposure time of the color frame is adjusted to be the same as the period in the environment. The filling time of the supplementary light is consistent, avoiding the appearance of color frames with uneven brightness, and avoiding the phenomenon of flickering. The judgment and adjustment methods based on color frames are the same as those based on black and white frames.

In addition, the present invention also provides another adjustment method: instead of comparing the brightness changes of the two frames before and after, directly adjust the exposure time of the first camera in any direction with a certain step size (for example, a fixed value of 20ms), until the first camera generates Stop the adjustment when the video does not flicker, the adjustment speed of this method will be slower. For example, the comparison of brightness, the calculation of the phase difference of the exposure period between the two cameras, and the adjustment of the exposure time of the first camera, etc., can all be performed by the CPU of the camera.

In the adjustment, the frames in the same shooting cycle can be fused to generate color frames. For example, the CPU fuses 2 black and white frames and 1 color frame in the same cycle to generate 2 color frames; fuses 2 black and white frames and 2 color frames in the same cycle to generate 2 color frames.

Referring to FIG. 10 , the present invention provides an embodiment of a method for adjusting the exposure time of a camera, for adjusting the exposure time of a first camera, wherein: each shooting cycle of the first camera includes at least 3 frames, The 3 frames include color frames and black and white frames, the first camera receives periodic fill light from the environment when shooting, and each fill light time period in the periodic fill light is shorter than the first camera. , the method includes: step S11, comparing the brightness of two adjacent frames of the same type in the same shooting cycle of the first camera, wherein the frame of the same type refers to a black and white frame, or The type is color frame; Step S22, adjust the exposure start time of the subsequent frames of the first camera according to the comparison result, until each of the adjusted fill light time periods is within a single fill light period of the first camera . After the adjustment is completed, the optional step S23 may be included to fuse the frames in the same shooting cycle to generate a color frame. For example: for a camera with 2 black and white frames + 1 color frame as one shooting cycle, 2 black and white frames in the same cycle are fused with the same color frame to generate 2 color frames; for 2 color frames + 1 For a camera with a shooting cycle of 4 black and white frames, 2 color frames in the same cycle are fused with the same black and white frame to generate 2 color frames; for a camera with 4 frames in one shooting cycle, 2 black and white frames in the same cycle The frame is fused with 2 color frames, resulting in 2 color frames.

Referring to FIG. 11 , the present invention further provides an embodiment of an exposure time adjustment device, which is used for performing the above method to adjust the exposure time of the first camera. Each shooting cycle of the first camera includes at least 3 frames, the 3 frames include color frames and black and white frames, the first camera receives periodic fill light from the environment when shooting, and the cycle Each supplementary light time period in the sexual supplementary light is shorter than the supplementary light period of the first camera. The exposure time adjustment device may be the first camera, or a program running in the processor of the first camera.

The exposure time adjustment device 4 includes: a brightness contrast module 41 and an adjustment module 42 . Wherein, the brightness comparison module is used to compare the brightness of two adjacent frames of the same type in the same shooting period of the first camera, wherein the frames of the same type refer to black and white frames or color frames frame. The adjustment module 42 is used to adjust the exposure start time of the subsequent frames of the first camera according to the comparison result, until each of the adjusted fill light time periods is within a single fill light period of the first camera. .

For example, the brightness comparison module 41 detects that: in the adjacent frames of the same type (for example, two adjacent color frames, or two adjacent black and white frames) of the first camera, the brightness of the pixel bar below the previous frame is higher than that of the previous frame. The brightness of the pixel bar below the back frame. Then it is concluded that there is a phase lag between the frames generated by the first camera and the frames generated by the second camera, and the lag phase is less than the phase of one frame, that is, the formula Δφ=φ ₁ +2n*π, -φ _{frame period} <φ ₁ <0°, in this embodiment -120°<φ ₁ <0°.

The adjustment module 42 adjusts the exposure start time of the first camera to the subsequent frames according to Δφ, and advances the exposure start time of the first camera to the subsequent frames until each of the adjusted fill light time periods is located in the Within a single fill light cycle of the first camera. Wherein, the advance time does not exceed the exposure period of one black and white frame.

The present invention also provides a program product, the program product includes computer-readable code instructions, when these computer-readable code instructions are executed by the first camera, the first camera can execute the foregoing method embodiments.

One or more of the above modules or units may be implemented in software, hardware or a combination of both. When any of the above modules or units are implemented in software, the software exists in the form of computer program instructions and is stored in the memory, and the processor can be used to execute the program instructions and implement the above method flow. The processor may include, but is not limited to, at least one of the following: a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), a microcontroller (MCU), or artificial intelligence Processors and other types of computing devices that run software, each computing device may include one or more cores for executing software instructions to perform operations or processing. The processor can be built in a SoC (system on chip) or an application specific integrated circuit (ASIC), or can be an independent semiconductor chip. In addition to the core for executing software instructions for operation or processing, the internal processing of the processor may further include necessary hardware accelerators, such as field programmable gate array (FPGA), PLD (Programmable Logic Device) , or a logic circuit that implements dedicated logic operations.

When the above modules or units are implemented in hardware, the hardware can be CPU, microprocessor, DSP, MCU, artificial intelligence processor, ASIC, SoC, FPGA, PLD, dedicated digital circuit, hardware accelerator or non-integrated discrete device Any one or any combination, which may or may not run the necessary software to perform the above method flow.

Claims

A method for adjusting the exposure time of a camera, which is used to adjust the exposure time of a first camera, wherein:

Each shooting cycle of the first camera includes at least 3 frames, the 3 frames include color frames and black and white frames, the first camera receives periodic fill light from the environment when shooting, and the cycle Each supplementary light time period in the sexual supplementary light is shorter than the supplementary light period of the first camera, wherein the method includes:

Compare the brightness of two adjacent frames of the same type in the same shooting period of the first camera, wherein the frames of the same type refer to black and white frames or color frames;

The exposure start time of subsequent frames of the first camera is adjusted according to the comparison result, until each adjusted light-filling time period is within a single fill-light period of the first camera.
The exposure time adjustment method according to claim 1, wherein the first camera comprises:

a lens for collecting light including the periodic fill light;

The sensor is configured to generate the color frame and the black and white frame at different moments according to the light collected by the lens.
The exposure time adjustment method according to claim 1, is characterized in that:

The periodic supplementary light is non-visible light, each of the adjusted supplementary light time periods corresponds to a black and white frame, and each of the supplementary light time periods is located in the supplementary light period of the corresponding black and white frame.
The exposure time adjustment method according to claim 1, wherein the total number of frames in the shooting period of the first camera is 3 frames, wherein the 3 frames include:

1 black and white frame and 2 consecutive color frames, or, 1 color frame and 2 consecutive black and white frames.
The exposure time adjustment method according to claim 1, is characterized in that:

The black and white frame has the same exposure period as the color frame.
The exposure time adjustment method according to claim 1, is characterized in that:

The periodic fill light comes from a fill light of the second camera.
The exposure time adjustment method according to claim 6, wherein:

The second camera and the first camera are located in the same shooting environment, and the first camera and the first camera have the same shooting period and the same fill light rule.
The exposure time adjustment method according to any one of claims 1-6, wherein:

The shooting period includes a plurality of black and white frames, the supplementary light period includes a plurality of supplementary light time periods, and the number of the supplementary light time periods is consistent with the number of black and white frames included in the shooting period.
The exposure time adjustment method according to any one of claims 1-6, wherein:

When in the two adjacent frames of the same type, the brightness change satisfies that the brightness of the lower pixel strip of the previous frame is greater than the brightness of the pixel strip below the subsequent frame, the phase difference of the shooting period between the first camera and the second camera is
n is an integer, the phase difference
It is used as a parameter for adjusting the exposure start time of subsequent frames of the first camera.
The exposure time adjustment method according to any one of claims 1-6, wherein:

When the brightness changes in the two adjacent frames of the same type satisfy that the brightness of the pixel bar above the previous frame is less than the brightness of the pixel bar above the next frame, the phase difference between the shooting periods of the first camera and the second camera is
n is an integer, the phase difference
It is used as a parameter for adjusting the exposure start time of subsequent frames of the first camera.
The exposure time adjustment method according to any one of claims 1-6, wherein:

In the two adjacent frames of the same type, the brightness change satisfies: the brightness of the pixel strip above the previous frame is greater than the brightness of the pixel strip above the rear frame; and the brightness of the pixel strip below the previous frame is smaller than the brightness of the pixel strip below the rear frame ; And, the number of pixels in the previous frame that is higher than the brightness of the rear frame is less than the number of pixels in the previous frame that is lower than the brightness of the rear frame;

Then: the phase difference of the shooting period of the first camera and the second camera is

the phase difference
It is used as a parameter for adjusting the exposure start time of subsequent frames of the first camera.
The exposure time adjustment method according to any one of claims 1-6, wherein:

In the two adjacent frames of the same type, the brightness change satisfies: the brightness of the pixel strip above the previous frame is greater than the brightness of the pixel strip above the rear frame; and the brightness of the pixel strip below the previous frame is smaller than the brightness of the pixel strip below the rear frame ; And, the number of pixel bars higher than the brightness of the rear frame in the previous frame is greater than the number of pixels lower than the brightness of the rear frame in the previous frame;

The phase difference between the shooting periods of the first camera and the second camera

the phase difference
It is used as a parameter for adjusting the exposure start time of subsequent frames of the first camera.
The exposure time adjustment method according to any one of claims 1-6, characterized in that, further comprising:

The color frames and black and white frames in the same cycle are fused to generate fused color frames.
The exposure time adjustment method according to any one of claims 1-6, wherein:

The sensor in the first camera that generates the at least 3 frames is a progressive exposure sensor.
A video camera comprising:

a lens for collecting light, the light received by the lens includes periodic supplementary light from the environment, and each supplementary light time period in the periodic supplementary light is shorter than the supplementary light period of the camera;

a sensor, configured to convert the optical signal collected by the lens into an electrical signal, and generate at least 3 frames per shooting cycle, and the 3 frames include color frames and black and white frames;

processor for:

Compare the brightness of two adjacent frames of the same type in the same shooting period, wherein the frames of the same type are black and white frames, or color frames;

The exposure start time of the subsequent frames of the camera is adjusted according to the comparison result, until each of the adjusted light fill time periods is within a single fill light period of the camera.
The camera of claim 15, wherein the sensor is used to:

The color frame and the black and white frame are generated at different times.
The camera of claim 15, wherein:

The periodic supplementary light is invisible light, and the processor is used for:

Each of the fill light time periods is adjusted to correspond to a black and white frame, and each of the fill light time periods is located in the fill light period of the corresponding black and white frame.
The camera according to claim 15, wherein the total number of frames in the shooting period of the camera is 3 frames, wherein the 3 frames include:

1 black and white frame and 2 consecutive color frames, or, 1 color frame and 2 consecutive black and white frames.
The camera of claim 15, wherein:

The periodic fill light comes from a fill light of another camera different from the camera.
The camera of claim 19, wherein:

The camera and the other camera are located in the same shooting environment, and the first camera and the first camera have the same shooting period and the same fill light rule.
The camera according to any one of claims 15-19, characterized in that:

The shooting period includes a plurality of black and white frames, the supplementary light period includes a plurality of supplementary light time periods, and the number of the supplementary light time periods is consistent with the number of black and white frames included in the shooting period.
The camera according to any one of claims 15-19, characterized in that:

When in the two adjacent frames of the same type, the brightness change satisfies that the brightness of the lower pixel strip of the previous frame is greater than the brightness of the pixel strip below the subsequent frame, the phase difference of the shooting period between the camera and the second camera is
n is an integer, the phase difference
It is used as a parameter for adjusting the exposure start time of subsequent frames of the camera.
The camera according to any one of claims 15-19, characterized in that:

The sensor is a progressive exposure sensor.
An exposure time adjustment device for adjusting the exposure time of a first camera, characterized in that:

Each shooting cycle of the first camera includes at least 3 frames, the 3 frames include color frames and black and white frames, the first camera receives periodic fill light from the environment when shooting, and the cycle Each supplementary light time period in the sexual supplementary light is shorter than the supplementary light period of the first camera, and it is characterized in that, the device includes:

A brightness comparison module, configured to compare the brightness of two adjacent frames of the same type in the same shooting period of the first camera, wherein the frames of the same type refer to a black and white frame or a color frame;

An adjustment module, configured to adjust the exposure start time of subsequent frames of the first camera according to the comparison result, until each adjusted light-filling time period is within a single fill-light period of the first camera.
The device of claim 24, wherein:

The periodic supplementary light is non-visible light, each of the adjusted supplementary light time periods corresponds to a black and white frame, and each of the supplementary light time periods is located in the supplementary light period of the corresponding black and white frame.
The apparatus according to claim 24, wherein the total number of frames in the shooting period of the first camera is 3 frames, wherein the 3 frames include:

1 black and white frame and 2 consecutive color frames, or, 1 color frame and 2 consecutive black and white frames.
The device according to any one of claims 24-26, characterized in that:

The shooting period includes a plurality of black and white frames, the supplementary light period includes a plurality of supplementary light time periods, and the number of the supplementary light time periods is consistent with the number of black and white frames included in the shooting period.
The device according to any one of claims 24-26, characterized in that:

When in the two adjacent frames of the same type, the brightness change satisfies that the brightness of the lower pixel strip of the previous frame is greater than the brightness of the pixel strip below the subsequent frame, the phase difference between the first camera and the second camera is
in,
- the phase of the exposure period, n is an integer, the phase difference
It is used as a parameter for adjusting the exposure start time of subsequent frames of the first camera.
A program product comprising computer readable code instructions which, when executed by a first camera, enable the first camera to perform any of the methods of claims 1-14.