TWI578783B - Focusing controlling and auto-exposing method and system - Google Patents

Description

Method and system for controlling focus and automatic exposure

The present invention relates to a method and system for performing focusing and exposure, and more particularly to a method and system for controlling focus and automatic exposure according to ambient brightness.

With the development of technology, it is more and more common for modern people to use mobile devices, such as smart phones or tablets. In order to respond to the user's usage habits and needs, most of these mobile devices are equipped with a camera to provide photography and photography.

When a user uses such a mobile device to take a photo, it is usually clicked on the screen of the mobile device to obtain a focus area or an area of focus exposure and white balance. In some mobile device designs, when the user clicks somewhere on the screen of the mobile device, the shutter release action is simultaneously completed to take a photo. In the above case, the user needs to hold the device with one hand and then click the screen with the other hand.

However, from the experience of most users, it is not stable enough to hold a mobile device with one hand when taking a photo, and the screen may vibrate when the other hand clicks on the screen. In particular, recently, screen sizes of mobile devices have become larger and larger, and it has become more difficult for a user to stably hold a mobile device with one hand for shooting, which makes it easy to take blurred pictures.

Embodiments of the present invention provide a method for controlling focus and automatic exposure, which is implemented in a control focus and automatic exposure system of a mobile camera. The control focus and automatic exposure system includes a camera module, a photosensitive module, an image calculation module, an image signal processor and a camera adjustment unit. The method for controlling the focus and the automatic exposure comprises: sampling the light by the camera module; using the photosensitive module to determine whether the brightness of the light sampled by the camera module reaches a preset brightness value and generating a judgment result; The group selects the image recognition method according to the judgment result to calculate the coordinates of the human eye gaze area; transmits the coordinates of the human eye gaze area to the image signal processor through the driving interface, and calculates the exposure adjustment value and the focus by the image signal processor. Adjusting the value; and adjusting the exposure amount and the focal length of the moving camera by the image signal processor according to the calculated focus adjustment value and the exposure adjustment value. The image recognition method is a visible light image recognition method or an infrared light image recognition method.

The embodiment of the invention further provides a control focus and automatic exposure system, comprising a camera module, a photosensitive module, an image calculation module, an image signal processor and an image adjustment unit. The camera module is used to sample light. The photosensitive module is connected to the camera module to determine whether the brightness of the light sampled by the camera module reaches a preset brightness value and generates a determination result. The image computing module is connected to the photosensitive module, and is configured to select an image recognition method according to the determination result to calculate a coordinate of the human eye gaze area of the user. The image signal processor is connected to the image computing module through the driving interface for calculating the exposure adjustment value and the focus adjustment value according to the coordinates of the human eye gaze area transmitted through the driving interface. The camera adjustment unit is connected to the image signal processor for adjusting the exposure amount and the focal length of the mobile camera according to the calculated focus adjustment value and the exposure adjustment value. The above image recognition method is a visible light image recognition method or an infrared light image recognition method.

In summary, the method and system for controlling focus and automatic exposure according to the embodiments of the present invention can select a visible light image recognition method or an infrared light image recognition method to calculate a human eye under different brightness conditions. Looking at the area coordinates, and then automatically calculating the exposure adjustment value and the focus adjustment value to adjust the exposure amount of the mobile camera With the focal length, you can control the focus and auto exposure in a well-lit environment or in a dim light environment to improve accuracy. In addition, the method and system for controlling focus and automatic exposure provided by the embodiments of the present invention do not require additional operations by the user, and the focus control and the adjustment of the exposure amount can be automatically performed, which is convenient for the user. Keep the stability of the mobile camera at all times during the imaging process and improve the image quality.

The detailed description of the present invention and the accompanying drawings are to be understood by the claims The scope is subject to any restrictions.

S101~S109‧‧‧Steps

F‧‧‧Area

P‧‧‧Double-channel camera

L1, L2, L3‧‧‧ infrared LED

4‧‧‧Control focus and automatic exposure system

41‧‧‧ camera module

411‧‧‧Two-channel camera

412‧‧‧Infrared LED array

42‧‧‧Photosensitive module

43‧‧‧Image Computing Module

44‧‧‧Image Signal Processor

45‧‧‧Video adjustment unit

451‧‧‧Image sensor

452‧‧‧ Focusing components

1 is a flow chart of a method of controlling focus and automatic exposure in an embodiment of the present invention.

2 is a schematic diagram showing the appearance of a mobile imaging device using a control focus and automatic exposure system in an embodiment of the present invention.

FIG. 2A is an enlarged schematic view of a region F of the mobile imaging device illustrated in FIG. 2. FIG.

3 is a schematic diagram of an infrared light image in an embodiment of the present invention.

4 is a functional block diagram of a control focus and automatic exposure system in an embodiment of the present invention.

Various illustrative embodiments are described more fully hereinafter with reference to the accompanying drawings. However, the inventive concept may be embodied in many different forms and should not be construed as being limited to the illustrative embodiments set forth herein. Rather, these exemplary embodiments are provided so that this invention will be in the In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Similar numbers always indicate similar components.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, such elements are not limited by the terms. These terms are used to distinguish one element from another. Thus, a first element discussed below could be termed a second element without departing from the teachings of the inventive concept. As used herein, the term "and/or" includes any of the associated listed items and all combinations of one or more.

The distance measurement method and apparatus will be described below in conjunction with the various embodiments, however, the following embodiments are not intended to limit the invention.

[Embodiment of Method of Controlling Focus and Automatic Exposure]

Please refer to FIG. 1. FIG. 1 is a flowchart of a method for controlling focus and automatic exposure in an embodiment of the present invention. As shown in FIG. 1 , the method for controlling focus and automatic exposure in the embodiment includes the following steps: sampling the light by the camera module (step S101); determining whether the brightness of the light sampled by the camera module is determined by the photosensitive module A preset brightness value is reached and a determination result is generated (step S103); the image calculation module selects an image recognition method according to the determination result to calculate a human eye gaze area coordinate (step S105); the human eye is gaze through the driving interface The area coordinates are transmitted to the image signal processor to calculate an exposure adjustment value and a focus adjustment value by the image signal processor (step S107); and the image signal processor is determined according to the calculated focus adjustment value and the exposure adjustment value The control image adjustment unit adjusts the exposure amount and the focal length of the moving image pickup device (step S109). It should be noted that in the method for controlling focus and automatic exposure in the embodiment, the image recognition method is a visible light image recognition method or an infrared light image recognition method.

The method for controlling focus and automatic exposure in this embodiment is applied to a mobile camera device provided with a control focus and automatic exposure system, so that the user can complete the process without taking any manual operation while using the mobile camera device for taking a picture. Focus and exposure adjustment. That is to say, before the user presses the shutter to take a picture, the focus control and the automatic exposure system perform a series of steps in the method of controlling the focus and the automatic exposure of the embodiment.

Further, as follows, when the focus and auto exposure system is controlled to start the method of controlling focus and automatic exposure in this embodiment, as shown in step S101, The camera module samples the light to know the ambient brightness conditions around the mobile camera. Then, as shown in step S103, the photosensitive module determines whether the brightness of the light sampled by the camera module reaches a preset brightness value and generates a determination result. In this embodiment, if the brightness of the light sampled by the camera module reaches a preset brightness value, that is, when the ambient light of the mobile camera device is sufficient, the determination result is in the visible light mode, so in the subsequent step, the movement is performed. The control focus and auto exposure system set by the camera will perform calculations for visible light mode. On the other hand, if the brightness of the light sampled by the camera module does not reach the preset brightness value, that is, the ambient light of the surrounding camera device is insufficient, the determination result is the infrared light mode, so in the subsequent step, the movement is performed. The control focus and auto exposure system set by the camera will be used for calculations in infrared mode.

After learning that the determination result is in the visible light mode or the infrared light mode, as shown in step S105, the image calculation module selects the image recognition method according to the determination result to calculate the coordinates of the human eye gaze area of the user.

In this embodiment, the camera module includes a dual channel camera having both a visible light channel and an infrared light channel. When the judgment result is visible light mode, the visible light channel of the dual-channel camera is turned on to obtain a visible light image in the direction of the user's face, and the visible light image is transmitted to the image calculation module, and then calculated by the image. The module calculates the coordinates of the human eye gaze area from the visible light image. In the visible light mode, the image computing module calculates the coordinates of the human eye gaze area by using the visible light image recognition method.

The visible light image recognition method will be described below. The visible light image recognition method calculates the human eye gaze area coordinates by using the eye orientation of the user determined by the visible light image and the plurality of sets of relative position coordinates between the user's pupil and the eyelid which are known in the visible light image. .

On the other hand, in the embodiment, when the judgment result is the infrared light mode, the infrared light channel of the two-channel camera is turned on to obtain an infrared light image toward the user's face, and the infrared light image is obtained. Transfer to the image calculation module, followed by the map The computing module calculates the coordinates of the human eye gaze area from the infrared light image.

The infrared light image recognition method is explained below. The infrared light image recognition method calculates the coordinates of the human eye gaze region by using the eye orientation of the user judged by the visible light image and the coordinates of the highest luminance center having the highest luminance value in the infrared light image. Further, in this embodiment, the camera module further has an infrared light LED array, and the LED array includes a plurality of infrared light LEDs. Please refer to FIG. 2 and FIG. 2A. FIG. 2 is a schematic diagram of the appearance of a mobile camera device for controlling a focus and an automatic exposure system according to an embodiment of the present invention. FIG. 2A is an enlarged schematic view of a region F of the mobile imaging device illustrated in FIG. 2. FIG. As shown in FIG. 2, the inside of the area F of the mobile camera is the position set by the camera module, and as shown in FIG. 2A, the infrared light included in the camera module provided in the area F of the mobile camera is included. The plurality of infrared light LEDs L1, L2, and L3 of the LED array are arranged in a specific shape, such as a triangle, around the two-channel camera P, but the present invention is not limited thereto.

Please refer to FIG. 3. FIG. 3 is a schematic diagram of an infrared light image in an embodiment of the present invention. In this embodiment, the infrared light LED can provide fill light (ie, under low light environment) in a dark environment, so that the camera module can capture an image of the user's face and the eyeball for successively facing The user's human eye gaze area coordinates are analyzed and calculated. It should be noted that, as shown in FIG. 2 and FIG. 3, the infrared light LED arrays are arranged in a specific shape in order to reflect the reflective spots arranged in a specific shape on the user's eyeball, and thus, It is very convenient to find the location of the eyeball, and then calculate the location and size of the user's face.

More specifically, the infrared light image recognition method in the embodiment can reduce the probability of misjudgment caused by other external point light sources. The main reason is that in the infrared light image recognition method in this embodiment, only By looking for the highlight area (such as the brightness 255 brightness level area, but the invention is not limited thereto), the user's eye position can be quickly determined by simple judgment. Moreover, the arrangement of the infrared light LED array can be used to accurately calculate the distance between the user's eye and the camera module, thereby improving the accuracy of the coordinate calculation of the human eye gaze area. In addition to infrared light LED arrays provide uniform fill light in low light conditions, reducing light damage for image recognition.

How to calculate the distance between the user's eyes and the camera module by using the arrangement of the infrared light LED arrays. For example, as shown in FIG. 4, the infrared light LED array has three infrared light LEDs, which are respectively L1. L2, L3, and the distance between the two infrared LEDs L1, L2, L3 are preset fixed. The manner in which the distance between the user's eyes and the camera module is calculated using the arrangement of the infrared light LED arrays is compared against the established mapping table. The method of establishing a mapping table is to find a standard individual (ie, an ordinary person), and obtain three infrared light images at a distance of 10 cm, 20 cm, and 30 cm (that is, the distance between the left eye of the standard individual and the camera module). It can be seen in each image that the three spots of the corresponding infrared light LEDs L1, L2, L3 are reflected on the left eye of the standard individual being photographed. Then, calculate and record the distance between the central points of the three light spots to obtain a distance mapping table, and then in most cases, only need to calculate the corresponding infrared light in the infrared light image collected by the camera module. The distance between the reflected points of the LEDs L1, L2, and L3 can be used to check the actual distance between the user's eyes and the camera module.

Then, referring back to FIG. 1, after the human eye gaze area coordinates calculated by the visible light image recognition method or the infrared light image recognition method, as shown in step S107, the system is used to contact the image calculation module. The driving interface of the image signal processor transmits the coordinate of the human eye gaze area calculated by the visible light image recognition method or the infrared light image recognition method to the image signal processor to calculate the exposure adjustment by the image signal processor Value and focus adjustment value. Finally, as shown in step S109, the exposure amount of the mobile camera is adjusted according to the calculated exposure adjustment value, and the focal length of the mobile camera is gradually adjusted according to the calculated focus adjustment value to complete the control focus and automatic exposure.

[Embodiment for Controlling Focus and Auto Exposure System]

Please refer to FIG. 4. FIG. 4 is a functional block diagram of a control focus and automatic exposure system according to an embodiment of the present invention. As shown in FIG. 4, the focus and automatic exposure of the embodiment are controlled. The optical system 4 includes a camera module 41, a photosensitive module 42, an image computing module 43, an image signal processor 44, and an imaging adjustment unit 45.

In this embodiment, the photosensitive module 42 is connected to the camera module 41, the image computing module 43 is connected to the photosensitive module 42, and the image signal processor 44 is connected to the driving interface (not shown). Like the calculation module 43, the image adjustment unit 45 is connected to the image signal processor 44. The camera module 41 is also connected to the image computing module 43 and includes a dual-channel camera 411 and an infrared light LED array 412 having both a visible light channel and an infrared light channel, wherein the dual-channel camera 411 is used to capture visible light images or infrared light. Light image for image recognition calculation. Further, the imaging adjustment unit 45 includes an image sensor 451 and a focusing component 452) to adjust the exposure amount of the moving imaging device and gradually adjust the focal length.

The operation and mechanism of the components of the camera module 41, the photosensitive module 42, the image calculation module 43, the image signal processor 44, and the image capturing adjustment unit 45 in the control focus and automatic exposure system 4 of the present embodiment are as described above. The detailed description in the embodiments will not be repeated here.

[Possible effects of the examples]

In summary, the method and system for controlling focus and automatic exposure according to the embodiments of the present invention can select a visible light image recognition method or an infrared light image recognition method to calculate a human eye under different brightness conditions. Looking at the coordinates of the area, and automatically calculating the exposure adjustment value and the focus adjustment value to adjust the exposure amount and focal length of the moving camera device, so that the focus can be controlled regardless of whether the light is sufficient or in a dark environment. Automatic exposure for increased accuracy. In addition, the method and system for controlling focus and automatic exposure provided by the embodiments of the present invention do not require additional operations by the user, and the focus control and the adjustment of the exposure amount can be automatically performed, which is convenient for the user. Keep the stability of the mobile camera at all times during the imaging process and improve the image quality.

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the invention.

S101~S109‧‧‧Steps

Claims (16)

A method for controlling focus and automatic exposure, which is implemented in one of a mobile camera device for controlling a focus and automatic exposure system, the control focus and automatic exposure system comprising a camera module, a photosensitive module, an image computing module, and a An image signal processor and a camera adjustment unit, the camera module is coupled to the image calculation module, and includes a dual channel camera having a visible light channel and an infrared light channel, and the method for controlling focus and automatic exposure The method includes: sampling the light by the camera module; determining, by the photosensitive module, whether the brightness of the light sampled by the camera module reaches a preset brightness value and generating a determination result according to the image; Selecting an image recognition method according to the determination result to calculate a coordinate of a human eye gaze area of a user; transmitting the coordinates of the human eye gaze area to the image signal processor through a driving interface, by the image signal processor Calculating an exposure adjustment value and a focus adjustment value; and calculating the focus adjustment value and the exposure adjustment value by the image signal The camera control unit adjusts an exposure amount and a focal length of the mobile camera device; wherein the image recognition method is a visible light image recognition method or an infrared light image recognition method; wherein, when the photosensitive mode The group determines that the brightness of the sampled light reaches the preset brightness value, and the visible light channel of the two-channel camera is turned on; when the photosensitive module determines that the brightness of the sampled light does not reach the preset brightness value, the two-channel camera The infrared light channel is turned on. The method for controlling focus and automatic exposure according to claim 1, wherein when the brightness of the light sampled by the camera module reaches the preset brightness value, the determination result is a visible light mode, and when the image mode is If the brightness of the light sampled by the group does not reach the preset brightness value, the judgment result is an infrared light mode. The method for controlling focus and automatic exposure according to claim 2, wherein when the visible light channel is turned on, a visible light image is acquired by the two-channel camera and transmitted to the image computing module; and when the infrared When the optical channel is turned on, an infrared image is obtained by the dual channel camera and transmitted to the image computing module. The method for controlling focus and automatic exposure according to claim 3, wherein in the visible light mode, the image computing module calculates the coordinates of the human eye gaze region by using the visible light image recognition method, and In the light mode, the image calculation module calculates the coordinates of the human eye gaze region by the infrared light image recognition method. The method for controlling focus and automatic exposure according to claim 4, wherein the visible light image recognition method uses an eye of the user to face a pupil between the pupil and the eyelid of the user in the visible light image. The relative position is used to calculate the coordinates of the human eye gaze area. The method for controlling focus and automatic exposure according to claim 4, wherein the infrared light image recognition method utilizes an eye orientation of the user and a highest brightness center of the infrared light image and the user A relative position between the eyelids is used to calculate the coordinates of the human eye gaze area. The method for controlling focus and automatic exposure according to claim 4, wherein the camera module further comprises an infrared light LED array, the LED array comprises a plurality of infrared light LEDs, and the plurality of infrared light LEDs are arranged In a specific shape. The image control unit includes an image sensor and a focusing component, wherein the image sensor is configured to adjust the moving camera according to the exposure adjustment value, as in the method of controlling the focus and the automatic exposure. The exposure component is used to gradually adjust the focal length of the mobile camera according to the focus adjustment value. A control focus and automatic exposure system includes: a camera module for sampling light; a photosensitive module coupled to the camera module for determining the camera module Whether the brightness of the sampled light reaches a predetermined brightness value and generates a determination result according to the result; an image calculation module is connected to the photosensitive module for selecting an image recognition method to calculate a use according to the determination result One of the human eyes looks at the area coordinates; an image signal processor is connected to the image computing module through a driving interface for calculating an exposure adjustment value according to the coordinates of the human eye gaze area transmitted through the driving interface. And an image adjustment unit; and an image adjustment unit, connected to the image signal processor for adjusting an exposure amount and a focal length of the mobile camera according to the calculated focus adjustment value and the exposure adjustment value; The camera module is also connected to the image computing module, and includes a dual channel camera having a visible light channel and an infrared light channel. When the photosensitive module determines that the brightness of the sampled light reaches the preset brightness a value, the visible light channel is turned on; and when the photosensitive module determines that the brightness of the sampled light does not reach the preset brightness value, the infrared light channel is turned on; The image recognition method based image recognition method of a visible light or an infrared light image recognition method. The control focus and automatic exposure system of claim 9, wherein when the brightness of the light sampled by the camera module reaches the preset brightness value, the determination result is a visible light mode, and when the camera module If the brightness of the sampled light does not reach the preset brightness value, the judgment result is an infrared light mode. The control focus and automatic exposure system of claim 10, wherein when the visible light channel is turned on, a visible light image is acquired by the dual channel camera and transmitted to the image computing module; and when the infrared light channel is When turned on, an infrared image is taken by the dual channel camera and transmitted to the image computing module. The control focus and automatic exposure system of claim 11, wherein in the visible light mode, the image computing module calculates the coordinates of the human eye gaze region by the visible light image recognition method, and the infrared light is Mode, the image calculation mode The group calculates the coordinates of the human eye gaze area by the infrared light image recognition method. The control focus and automatic exposure system of claim 12, wherein the visible light image recognition method uses an eye of the user to face a pupil between the user and the eyelid of the visible light image. The position is used to calculate the coordinates of the human eye gaze area. The control focus and automatic exposure system of claim 12, wherein the infrared light image recognition method utilizes an eye orientation of the user and a highest brightness center of the infrared light image and an eyelid of the user A relative position between the two is used to calculate the coordinates of the human eye gaze area. The control focus and automatic exposure system of claim 11, wherein the camera module further comprises an infrared light LED array, the LED array comprises a plurality of infrared light LEDs, and the plurality of infrared light LEDs are arranged in a Specific shape. The control focus and automatic exposure system of claim 9, wherein the image adjustment unit comprises an image sensor and a focus component, wherein the image sensor is configured to adjust the mobile camera according to the exposure adjustment value The exposure component is used to gradually adjust the focal length of the mobile camera according to the focus adjustment value.