CN110012235B - Imaging exposure control method and device, computer readable storage medium, system - Google Patents

Abstract

The invention relates to an imaging exposure control method and device, a computer readable storage medium and an imaging exposure control system. The imaging exposure control method comprises the following steps: step S1, initializing the CMOS; step S2, acquiring an image; step S3, calculating an exposure parameter a based on the currently acquired image; step S4, configuring the CMOS according to the exposure parameter a, and acquiring an image; step S5, decoding the currently acquired image; step S6, if the decoding is successful, executing step S3; step S7, judging whether overtime exists, if not, executing step S3; in step S8, the CMOS is configured with a fixed exposure parameter b, and an image is acquired. The scheme provided by the invention is beneficial to collecting useful images in different scene modes and acquiring effective bar code information.

Description

Imaging exposure control method and device, computer readable storage medium, system

technical field

The present invention relates to the technical field of barcode reading, and in particular, to an imaging exposure control method and device, a computer-readable storage medium, and a system.

Background technique

Today, barcode scanners are widely used in mobile payment, express warehousing and logistics, books, clothing, medicine and other fields. In different usage scenarios, due to different barcode display media (mainly paper barcodes and screen barcodes), different lighting environments, different imaging systems, and different movement states of scanned barcodes, in order to obtain high quality The imaging effect of the barcode scanner has a great challenge to the imaging control system of the barcode scanner.

At present, most barcode scanners use the automatic exposure mode of the camera to capture images. In this mode, when the brightness of the captured image is too low, the camera will increase the exposure time or increase the exposure gain. The overall brightness of the captured image. When the brightness of the captured image is too high, the camera will reduce the overall brightness of the captured image by reducing the exposure time or reducing the exposure gain to avoid overexposure of the image. In practical applications, when the target brightness is set high, although it has better performance when scanning paper barcodes, when scanning barcodes on the screen, because the screen itself will emit light, when the barcodes on the screen are slightly farther away from the camera, The entire screen will be overexposed. When the barcode on the screen quickly enters the viewing angle from outside the camera's viewing angle, overexposure will also occur. After a period of time, the captured image will be adjusted to the ideal brightness. When the target brightness setting is low, there is a longer depth of field and higher motion tolerance when scanning barcodes on the screen, and paper barcodes are almost completely unrecognizable due to the low brightness.

Chinese invention patent application CN106846670A discloses a barcode reading method for the POS terminal, which automatically switches the parameters of the camera module at every N frame interval during the barcode reading process. The parameters of the camera module include target brightness and exposure value. After each parameter switching, it still takes some time for the image brightness to converge to the target brightness. This method switches the parameters of the camera module every N frames. When N takes a larger value, the camera has enough time to converge the image brightness to the target brightness, but if the current scene requires another target brightness, It is necessary to wait until the parameters are switched and then converge to the target brightness before the ideal image can be collected. This method is inefficient, and it takes too long from triggering to successful decoding, which affects the user experience. When N takes a small value, the camera does not have enough time to converge the image brightness to the target brightness and switches the parameters, which makes the barcode scanner only capture usable images within the applicable range of the two initial exposure values.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide an imaging exposure control method and device, a computer-readable storage medium, and a system, through which the imaging exposure control method helps to collect useful images and obtain valid barcode information in different scene modes.

In order to solve the above technical problems, the present invention provides an imaging exposure control method, which is suitable for barcode scanners, including:

Step S1, initialize CMOS;

Step S2, acquiring an image;

Step S3, calculating the exposure parameter a based on the currently acquired image;

Step S4, configure the CMOS according to the exposure parameter a, and acquire an image;

Step S5, decoding the currently acquired image;

Step S6, if the decoding is successful, perform step S3;

Step S7, judging whether it has timed out, and if it has not timed out, go to step S3;

Step S8, configure the CMOS with a fixed exposure parameter b, and acquire an image;

Step S9, decoding the currently acquired image;

Step S10, if the decoding is successful, perform step S8;

In step S11 , it is judged whether it has timed out, and if it has not timed out, go to step S8 , and if it has timed out, go back to step S3 .

According to an embodiment of the present invention, the calculation method of the exposure parameter a is as follows:

Among them, a' is the value set by the exposure parameter a last time, t is the target brightness, r is the image reduction scale, i and j are the abscissa and ordinate, and m and n are the width and height of the reduced image.

According to an embodiment of the present invention, in step S7, it is determined whether the duration from the previous successful decoding exceeds N1 seconds, and if it does not exceed N1 seconds, step S3 is performed.

According to an embodiment of the present invention, in step S11, it is judged whether the duration from the previous successful decoding exceeds N2 seconds, if it does not exceed N2 seconds, execute step S8, if it exceeds N2 seconds, return to step S3.

According to an embodiment of the present invention, N1=N2.

According to an embodiment of the present invention, the exposure parameter b is determined according to the model of the CMOS and in combination with the performance of the screen barcode under different exposure parameters.

According to an embodiment of the present invention, the value of the exposure parameter b is smaller than the value of the exposure parameter a.

According to an embodiment of the present invention, in step S1, the corresponding configuration table of the CMOS is initialized according to the model of the CMOS, and the automatic exposure mode in the CMOS configuration table is turned off.

The present invention also provides an imaging exposure control device suitable for the aforementioned imaging exposure control method, comprising:

CMOS module;

an image acquisition module, suitable for acquiring images;

an exposure parameter module, adapted to obtain exposure parameters to configure the CMOS module;

an image decoding module, adapted to decode the currently acquired image;

a comparison module, suitable for judging whether the decoding is successful;

The timeout module is suitable for judging whether there is a timeout.

The present invention also provides a computer-readable storage medium on which computer instructions are stored, and when the computer instructions are executed, the steps of any one of the imaging exposure control methods described above are executed.

The present invention also provides an imaging exposure control system, comprising a memory and a processor, wherein the memory stores computer instructions that can be executed on the processor, and is characterized in that when the processor runs the computer instructions The steps of any one of the imaging exposure control methods described above are performed.

The invention collects images by controlling the exposure of CMOS to switch between two modes. One way is to maintain the image brightness at a certain level of automatic exposure, and the other way is to lock the exposure time at a fixed value. The methods are crossed and do not affect each other, so as to obtain valid barcode information.

Description of drawings

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein:

1 is a flowchart of an imaging exposure control method according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an imaging exposure control device according to an embodiment of the present invention.

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Numerous specific details are set forth in the following description to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways than those described herein, and thus the present invention is not limited by the specific embodiments disclosed below.

As shown in this application and in the claims, unless the context clearly dictates otherwise, the words "a", "an", "an" and/or "the" are not intended to be specific in the singular and may include the plural. Generally speaking, the terms "comprising" and "comprising" only imply that the clearly identified steps and elements are included, and these steps and elements do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

When describing the embodiments of the present application in detail, for the convenience of explanation, the cross-sectional views showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of the protection of the present application. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in the actual production.

For convenience of description, spatially relative terms such as "below", "below", "below", "below", "above", "on", etc. may be used herein to describe an element shown in the figures or the relationship of a feature to other elements or features. It will be understood that these spatially relative terms are intended to encompass other directions of the device in use or operation than those depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary words "below" and "below" can encompass both an orientation of above and below. Devices may also have other orientations (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein should be interpreted accordingly. In addition, it will also be understood that when a layer is referred to as being 'between' two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.

In the context of this application, descriptions of structures where a first feature is "on" a second feature can include embodiments in which the first and second features are formed in direct contact, as well as further features formed on the first and second features. Embodiments between the second features such that the first and second features may not be in direct contact.

FIG. 1 is a flowchart of an imaging exposure control method according to an embodiment of the present invention. The so-called exposure control refers to the process of accurately exposing the target image through the reasonable configuration of parameters such as aperture, shutter and ISO based on the camera's metering results. The present invention provides an imaging exposure control method suitable for a barcode scanner. The CMOS is configured by exposure parameters, thereby controlling the exposure intensity of the CMOS and acquiring a target image containing a clear barcode, thereby recognizing the barcode.

The present invention provides an imaging exposure control method, comprising:

Step S1, initialize the CMOS. CMOS (Complementary Metal-Oxide-Semiconductor), a complementary metal oxide semiconductor, is mainly a semiconductor made of silicon and germanium, which makes it coexist on CMOS with N (charged) and P ( The semiconductor with + electric) grade, saves the most basic information for the barcode scanner system to guide.

Step S2, acquiring an image, usually the acquired image contains a barcode. Here is the first frame of image collected after the CMOS initialization configuration table takes effect.

Step S3, calculating the exposure parameter a based on the currently acquired image. That is, the exposure parameter a can be calculated according to the brightness and size of the currently acquired image.

Step S4, configure the CMOS according to the exposure parameter a, so as to control the exposure intensity of the CMOS and acquire an image.

In step S5, the currently acquired image is decoded to obtain useful barcode information, and the barcode reading is completed.

Step S6, if the decoding is successful and useful barcode information can be obtained, then step S3 is performed.

In step S7, it is judged whether it has timed out, and if it has not timed out, step S3 is executed. If decoding fails and times out, go to the next step.

Step S8, configure the CMOS with a fixed exposure parameter b, control the exposure intensity of the CMOS, and acquire an image.

In step S9, the currently acquired image is decoded to obtain useful barcode information, and the barcode reading is completed.

In step S10, if the decoding is successful and useful barcode information can be obtained, step S8 is executed.

In step S11, it is judged whether it has timed out, and if it has not timed out, step S8 is executed. If the decoding fails and times out, return to step S3 to switch exposure parameters.

It should be noted that the scene scanned by the barcode scanner usually includes paper barcodes and screen barcodes. Steps S3 to S7 can be understood as controlling the exposure intensity of the CMOS according to the brightness of the real-time scene, which is relatively suitable for the scene of scanning paper barcodes. Usually, increasing the brightness of the target can make the image of the paper barcode clearer and brighter. The exposure parameter a is calculated by the currently acquired image, so that the exposure convergence speed when recognizing the paper barcode is faster and can be obtained more quickly. Ideal for paper barcode images. After the decoding is successful, the scene will not change much in a short period of time, so the exposure method when the decoding is successful is maintained to further improve the efficiency of collecting ideal images. If the decoding is unsuccessful and a timeout occurs, the screen barcode scene may be entered, and the exposure mode needs to be switched.

Steps S8 to S11 can be understood as being applicable to the scenario of scanning barcodes on the screen. When scanning the barcode on the screen, since the screen itself will emit light, when the barcode on the screen is a little farther from the camera, the entire screen will be overexposed, and when the barcode on the screen quickly enters the viewing angle from outside the camera, overexposure will also occur. A fixed exposure parameter b makes it possible to quickly obtain rational screen barcode images when recognizing screen barcodes. After the decoding is successful, the scene will not change much in a short time, so the exposure method when the decoding is successful is maintained. If decoding is unsuccessful and a timeout occurs, it may be that a paper barcode scene has been entered, and the exposure mode needs to be switched, and the process returns to step S3 to step S7.

The imaging exposure control method provided by the present invention mainly switches back and forth between the scene of paper barcode and screen barcode, and controls the exposure intensity of CMOS by acquiring continuously updated exposure parameters a and fixed exposure parameters b, so as to obtain a more ideal available barcode images, improving the efficiency of capturing ideal images. When the decoding fails and the timeout occurs, switch between two scenarios. Using this method, whether it is a fast-moving mobile phone screen barcode or a dimly lit paper barcode, you can quickly switch the scene to capture the ideal image. available barcode images.

Preferably, the calculation method of the exposure parameter a in step S3 is as follows:

When calculating the exposure parameter a, it is not necessary to calculate all the pixels of the acquired image, but to calculate the reduced image. Among them, a' is the value set by the exposure parameter a last time, t is the target brightness, r is the image reduction scale, i and j are the abscissa and ordinate, and m and n are the width and height of the reduced image. The function f(x, y) represents the pixel point with the coordinates (x, y) in the image. Because the value of the exposure parameter a is too large or too small, it is meaningless. Through the above calculation method, the value of the exposure parameter a can be limited to within a reasonable range.

Preferably, in step S7, it is judged whether the duration from the previous successful decoding exceeds N1 seconds, and if it does not exceed N1 seconds, step S3 is performed. The N1 seconds here can be understood as the time since the last successful decoding. Once it times out, the exposure method is switched, and a fixed exposure parameter b is selected to configure the CMOS. In this way, when the dimly lit paper barcode is converted into a fast-moving mobile phone screen barcode, the barcode scanner can quickly capture the ideal useful image.

Preferably, in step S11, it is judged whether the time from the previous successful decoding exceeds N2 seconds, and if it does not exceed N2 seconds, step S8 is performed to continue to configure the CMOS with exposure parameter b. The N2 seconds here can be understood as the time since the last successful decoding. Once it times out, the exposure method is switched, and the exposure parameter a is obtained to configure the CMOS. In this way, when the fast-moving mobile phone screen barcode is converted into a paper barcode with dim brightness, the barcode scanner can quickly capture the ideal useful image.

As an example and not a limitation, the duration of N1 seconds in step S7 and the duration of N2 seconds in step S11 may be selected according to actual needs. Preferably, N1=N2. When N1 and N2 take reasonable values, the imaging exposure control method provided by the present invention only needs to wait for at most one frame of image to switch exposure parameters to obtain an ideal useful barcode image.

From the above, using an imaging exposure control method of the present invention, whether it is a fast-moving mobile phone screen barcode or a paper barcode with a dim brightness, it is possible to quickly switch scenes and select different exposure parameters to quickly collect ideal useful images. images to improve barcode reading efficiency.

Preferably, in step S8, the exposure parameter b is determined according to the model of the CMOS and in combination with the performance of the screen barcode under different exposure parameters. Exposure parameter b is a fixed value and will not be changed after it is determined. More preferably, the value of the exposure parameter b is smaller than the value of the exposure parameter a. It is easy to understand that due to the high brightness of the screen barcode and the low brightness of the paper barcode, the exposure parameter b corresponding to the two is smaller than the exposure parameter a.

Preferably, in step S1, the corresponding configuration table of the CMOS is initialized according to the model of the CMOS, and the automatic exposure mode in the CMOS configuration table is turned off. In subsequent steps, exposure parameter a or exposure parameter b is selected.

It should be noted that some types of CMOS do not take effect immediately after the parameters are configured, and may take effect every frame, that is, the new exposure parameters are started after the next frame of image is captured. If the next frame of image is ignored, this method has no substantial impact.

The imaging exposure method in the above embodiment is to obtain exposure parameter a as the first choice, and then switch between the two scenarios of screen barcode and paper barcode, that is, switch between exposure parameter b and exposure parameter a. It is easy to understand that it is also possible to obtain the exposure parameter b as the first choice, and then switch between the two scenarios of the paper barcode and the screen barcode. The essence of the two methods is the same. The specific imaging exposure method is as follows:

Step V1, initialize CMOS;

Step V2, configure the CMOS with a fixed exposure parameter b, and acquire an image;

Step V3, decode the currently acquired image; if the decoding is successful, execute Step V2;

Step V4, judging whether it has timed out, and if it has not timed out, execute step V2;

Step V5, calculating the exposure parameter a based on the currently acquired image;

Step V6, configure the CMOS according to the exposure parameter a, and acquire an image;

Step V7, decode the currently acquired image, and execute Step V5 if the decoding is successful;

In step V8, it is judged whether it has timed out, and if it has not timed out, step V5 is executed, and if it has timed out, it returns to step V2.

FIG. 2 is a schematic structural diagram of an imaging exposure control device according to an embodiment of the present invention. As shown in the figure, an imaging exposure control device, suitable for the aforementioned imaging exposure control method, includes:

CMOS module 210 .

An image acquisition module 220 is adapted to acquire images. It is used to perform the action of acquiring images in steps S2, S4 and S8.

The exposure parameter module 230 is adapted to acquire the exposure parameter a or the exposure parameter b to configure the CMOS module.

The image decoding module 240 is adapted to decode the currently acquired image to acquire barcode information.

The comparison module 250 is adapted to determine whether the decoding is successful.

The timeout module 260 is adapted to determine whether there is a timeout.

The present invention also provides a computer-readable storage medium. The computer-readable storage medium is a non-volatile storage medium or a non-transitory storage medium, on which computer instructions are stored. When the computer instructions are run, any one of the above imaging exposures is performed. The steps corresponding to the control method are not repeated here.

The present invention also provides an imaging exposure control system, including a memory and a processor, the memory stores computer instructions that can run on the processor, and the processor executes the steps of any of the above imaging exposure control methods when running the computer instructions.

This application uses specific terms to describe the embodiments of the application. Such as "one embodiment," "an embodiment," and/or "some embodiments" means a certain feature, structure, or characteristic associated with at least one embodiment of the present application. Therefore, it should be emphasized and noted that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in different places in this specification are not necessarily referring to the same embodiment . Furthermore, certain features, structures or characteristics of the one or more embodiments of the present application may be combined as appropriate.

Some aspects of the imaging exposure control method of the present invention may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as a "data block", "module", "engine", "unit", "component" or "system". The processor may be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors , controller, microcontroller, microprocessor, or a combination thereof. Furthermore, aspects of the present application may be embodied as a computer product comprising computer readable program code embodied in one or more computer readable media. For example, computer-readable media may include, but are not limited to, magnetic storage devices (eg, hard disks, floppy disks, magnetic tapes, ...), optical disks (eg, compact discs, CDs, digital versatile disks, DVDs, ...), smart cards, and flash memory devices ( For example, cards, sticks, key drives...).

A computer-readable medium may contain a propagated data signal with the computer program code embodied therein, for example, on baseband or as part of a carrier wave. The propagating signal may take a variety of manifestations, including electromagnetic, optical, etc., or a suitable combination. A computer-readable medium can be any computer-readable medium other than a computer-readable storage medium that can communicate, propagate, or transmit a program for use by being coupled to an instruction execution system, apparatus, or device. Program code on a computer readable medium may be propagated by any suitable medium, including radio, cable, fiber optic cable, radio frequency signal, or the like, or a combination of any of the foregoing.

Furthermore, unless explicitly stated in the claims, the order of processing elements and sequences described in the present application, the use of numbers and letters, or the use of other names are not intended to limit the order of the procedures and methods of the present application. While the foregoing disclosure discusses by way of various examples some embodiments of the invention that are presently believed to be useful, it is to be understood that such details are for purposes of illustration only and that the appended claims are not limited to the disclosed embodiments, but rather The requirements are intended to cover all modifications and equivalent combinations falling within the spirit and scope of the embodiments of the present application. For example, although the system components described above may be implemented by hardware devices, they may also be implemented by software-only solutions, such as installing the described systems on existing servers or mobile devices.

Similarly, it should be noted that, in order to simplify the expressions disclosed in the present application and thus help the understanding of one or more embodiments of the present application, in the foregoing description of the embodiments of the present application, various features are sometimes combined into one embodiment, in the drawings or descriptions thereof. However, this method of disclosure does not imply that the subject matter of the application requires more features than those mentioned in the claims. Indeed, there are fewer features of an embodiment than all of the features of a single embodiment disclosed above.

Some examples use numbers to describe quantities of ingredients and attributes, it should be understood that such numbers used to describe the examples, in some examples, use the modifiers "about", "approximately" or "substantially" to retouch. Unless stated otherwise, "about", "approximately" or "substantially" means that a variation of ±20% is allowed for the stated number. Accordingly, in some embodiments, the numerical parameters set forth in the specification and claims are approximations that can vary depending upon the desired characteristics of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and use a general digit reservation method. Notwithstanding that the numerical fields and parameters used in some embodiments of the present application to confirm the breadth of their ranges are approximations, in particular embodiments such numerical values are set as precisely as practicable.

Although the present invention has been described with reference to the present specific embodiments, those of ordinary skill in the art will recognize that the above embodiments are only used to illustrate the present invention, and can be made without departing from the spirit of the present invention Various equivalent changes or substitutions, therefore, as long as the changes and modifications to the above-mentioned embodiments within the spirit and scope of the present invention will fall within the scope of the claims of the present application.

Claims (8)

1. An imaging exposure control method is suitable for a bar code scanner and comprises the following steps:

step S1, initializing the CMOS;

step S2, acquiring an image, wherein the acquired image usually contains a bar code, and the image is a first frame image acquired after a CMOS initialization configuration table takes effect;

a step S3 of calculating an exposure parameter a based on the image acquired in the step S2;

step S4, configuring the CMOS according to the exposure parameter a, thereby controlling the exposure intensity of the CMOS and obtaining an image;

step S5, decoding the image obtained in step S4 to obtain useful bar code information, and completing bar code reading;

step S6, if the decoding is successful and the useful barcode information can be obtained, step S3 is executed, and if the decoding is failed, step S7 is executed;

step S7, judging whether overtime exists, if not, executing step S3, if decoding overtime exists, entering the next step S8;

step S8, configuring the CMOS with a fixed exposure parameter b, controlling the exposure intensity of the CMOS and obtaining an image;

step S9, decoding the image obtained in step S8 to obtain useful bar code information, and completing bar code reading;

step S10, if decoding is successful and useful bar code information can be obtained, executing step S8, if decoding is failed, executing step 11;

step S11, judging whether overtime exists, if not, executing step S8, if overtime exists, returning to step S3, and switching exposure parameters;

the calculation method of the exposure parameter a is as follows:

wherein a' is a value set last time by the exposure parameter a, t is target brightness, r is image reduction scale, i and j are abscissa and ordinate, and m and n are width and height of the reduced image;

and the exposure parameter b is determined according to the model of the CMOS and the representation of the screen bar code under different exposure parameters.

2. The imaging exposure control method according to claim 1, wherein in step S7, it is determined whether the time length from the previous decoding success exceeds N1 seconds, and if not, step S3 is executed.

3. The imaging exposure control method according to claim 2, wherein in step S11, it is determined whether a time period from a previous decoding success exceeds N2 seconds, if not exceeding N2 seconds, step S8 is executed, and if exceeding N2 seconds, step S3 is returned to.

4. The imaging exposure control method of claim 2, wherein N1 is N2.

5. The imaging exposure control method according to claim 1, wherein the value of the exposure parameter b is smaller than the value of the exposure parameter a.

6. The imaging exposure control method according to claim 1, wherein in step S1, the corresponding configuration table is initialized according to the model of the CMOS, and the automatic exposure mode in the CMOS configuration table is turned off.

7. A computer-readable storage medium having stored thereon computer instructions, wherein the computer instructions are operable to perform the steps of the imaging exposure control method of any of claims 1 to 6.

8. An imaging exposure control system comprising a memory and a processor, the memory having stored thereon computer instructions executable on the processor, wherein the processor, when executing the computer instructions, performs the steps of the imaging exposure control method of any one of claims 1 to 6.

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