Image shooting device and image shooting method thereof

Abstract

The invention provides an image shooting device and an image shooting method thereof. The image shooting device comprises a plurality of infrared light sources, an image shooting device and a controller. The infrared light sources have different light types. The image shooting device is used for shooting image information. The controller is coupled with the infrared light source and the image shooting device. The controller turns on or off the infrared light sources according to the light intensity information, and at least one of the infrared light sources is turned on in the image shooting action.

Description

Technical Field

[0001] The present invention relates to an image capturing device and an image capturing method thereof, and more particularly to an image capturing device and an image capturing method thereof for infrared light images. Background Art

[0002] In order to enhance the safety in life, image capturing devices with night vision functions are commonly used devices in life. In current technologies, the body illumination range of an image capturing device with a night vision function (such as a video recorder) is usually limited to the center of the field of view. The purpose of such a setting is to provide a longer irradiation distance. However, in a video recorder with a wide-angle shooting function, the surrounding of its image is often dark and there is no image, and it is impossible to capture the same field of view angle as in the daytime state. In addition, the infrared light sources commonly used in known video recorders are all light sources with a highly directional light pattern, so that in the night mode, when the object to be captured is too close, it will cause overexposure of the infrared light illumination, making the captured image unreadable. Summary of the Invention

[0003] The present invention is directed to an image capturing device and an image capturing method thereof, which can effectively improve the quality of the captured image.

[0004] According to an embodiment of the present invention, the image capturing device includes a plurality of infrared light sources, an image capture device, and a controller. The infrared light sources respectively have a variety of different light patterns. The image capture device is used to capture image information. The controller is coupled to the infrared light sources and the image capture device. The controller turns on or off each infrared light source according to the light intensity information, wherein at least one of the infrared light sources is turned on during the image capturing operation.

[0005] According to an embodiment of the present invention, the image capturing method includes: providing a plurality of infrared light sources, wherein the infrared light sources respectively have a variety of different light patterns; providing an image capture device to capture image information; and providing a controller to turn on or off each infrared light source according to the light intensity information, wherein at least one of the infrared light sources is turned on during the image capturing operation.

[0006] Based on the above, the image capturing device of the present invention sets a plurality of infrared light sources respectively having a plurality of different light patterns, and determines the number of infrared light sources to be turned on according to the light intensity information of the shooting scene. In this way, during the infrared image capturing operation, different light pattern infrared light sources can be activated according to the state of the shooting scene to perform adaptive supplementary lighting. And when the light intensity is too high, it is also possible to prevent possible overexposure by turning off some of the infrared light sources, improving the quality of the captured image. Brief Description of the Drawings

[0007] Figure 1Schematic diagram of an image capturing device showing an embodiment of the present invention.

[0008] Figure 2A And Figure 2B Schematic diagrams respectively showing different embodiments of the image capturing operation of the image capturing device according to the embodiments of the present invention.

[0009] Figure 3 Flowchart of the image capturing method of the image capturing device according to an embodiment of the present invention.

[0010] Figure 4 Flowchart of another embodiment of the image capturing method of the image capturing device according to an embodiment of the present invention.

[0011] Figure 5 Flowchart of the image capturing method according to another embodiment of the present invention. Detailed implementation manners

[0012] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals are used in the drawings and the description to refer to the same or like parts.

[0013] Please refer to Figure 1 , Figure 1 Schematic diagram of an image capturing device showing an embodiment of the present invention. The image capturing device 100 may have a night vision function. The image capturing device 100 includes a plurality of infrared light sources 111, 112, an image capture unit 120, and a controller 130. The infrared light sources 111, 112 may respectively have different light patterns. Further, the infrared light sources 111, 112 may respectively have different beam transmission ranges. For example, the infrared light source 111 may be an infrared light emitting diode (IR LED) with a wide-angle light pattern illumination, and the infrared light source 112 may be an infrared light emitting diode with a high-directivity light pattern. Among them, the beam transmission range of the infrared light source 111 may be larger than that of the infrared light source 112.

[0014] The image capture device 120 can be an infrared camera with infrared image capture capabilities. When the image capture device 120 performs an image capture operation, the infrared light sources 111 and 112 can be activated to provide the light required for the image capture operation. The image capture device 120 can perform a sensing operation on the light intensity of the captured scene and thereby obtain a light intensity information. On the other hand, the image capture device 120 can also set the exposure setting time during the image capture operation according to the sensed light intensity information. Among them, when the captured scene has a relatively high light intensity information, the image capture device 120 can set a relatively low exposure setting time. When the captured scene has a relatively low light intensity information, the image capture device 120 can set a relatively high exposure setting time.

[0015] In addition, the controller 130 is coupled to the infrared light sources 111 and 112 and the image capture device 120. The controller 130 can receive the light intensity information obtained by the image capture device 120 and control the on or off state of the infrared light sources 111 and 112 according to the light intensity information. In detail, when the image capture device 100 is to perform an image capture operation, the controller 130 can first activate the infrared light source 111 and cause the infrared light source 111 to provide an illumination beam. Then, the controller 130 can receive the light intensity information and compare the light intensity information with a default first threshold. When the light intensity information is not greater than the default first threshold, the controller 130 can determine that the light intensity of the infrared light in the captured scene is insufficient and correspondingly turn on the infrared light source 112. Here, since the infrared light source 112 is a light source with a highly directional light pattern, it can effectively perform a supplementary lighting operation on a specific area of the image capture scene of the image capture device 120. Thereby, the image capture device 120 can obtain a captured image with relatively high clarity.

[0016] On the contrary, if when the infrared light source 111 is turned on and the infrared light source 112 is turned off, when the controller 130 determines that the light intensity information is not greater than the default first threshold, the state of the infrared light source 111 being turned on and the infrared light source 112 being turned off can be maintained, and the image capture device 120 can capture a captured image and generate image information.

[0017] On the other hand, if when both the infrared light sources 111 and 112 are turned on, the controller can further compare the light intensity information obtained by the image capture device 120 at this time with a default second threshold, where the second threshold is greater than the first threshold. When the light intensity information is greater than a default second threshold, the controller 130 can determine that the light intensity of the captured scene at this time is too high, and if an image capture operation is performed, overexposure may occur. Therefore, correspondingly, the controller 130 can turn off the infrared light source 112, maintain the state of the infrared light source 111 being turned on, and then cause the image capture device 120 to perform an image capture operation.

[0018] Please refer to the following in synchronization Figure 1 、 Figure 2A and Figure 2B 。 Figure 2A and Figure 2B respectively show schematic diagrams of different embodiments of the image capturing operation of the image capturing device according to embodiments of the present invention. In Figure 2A , in the state of the night vision mode, when performing the image capturing operation for the shooting scenes of a large field of view and a close-up, the controller 130 can activate the infrared light source 111 and turn off the infrared light source 112. By providing a wide-angle light type illumination beam through the infrared light source 111, the image capture device 120 can obtain clear image information 210.

[0019] In Figure 2B , also in the state of the night vision mode, when performing the image capturing operation for a relatively long-distance shooting scene, the controller 130 can activate both the infrared light sources 111 and 112. In addition to providing a wide-angle light type infrared light illumination beam through the infrared light source 111, a high-directivity light type infrared light illumination beam is provided through the infrared light source 112 to supplement the infrared illumination brightness required for an object at a relatively long distance, so that the image capture device 120 can obtain clear image information 220.

[0020] Please refer to again Figure 1 , in other embodiments of the present invention, the infrared light source of the image capturing device 100 may also be three or more. Under such conditions, the controller 130 can preset multiple thresholds corresponding to the number of infrared light sources. And by comparing the light intensity information with the multiple thresholds, it is determined the range where the light intensity of the infrared light in the shooting scene is located, and the number of infrared light sources to be turned on is determined. It is worth mentioning that regardless of the magnitude of the light intensity information, the infrared light source 111 is constantly turned on during the image capturing operation.

[0021] Incidentally, the controller 130 can be built into the imaging device 120 or disposed outside the imaging device 120. In addition, the controller 130 can be a processor with computing capabilities. Alternatively, the controller 130 can be designed by a hardware description language (HDL) or any other design method of digital circuits well-known to those of ordinary skill in the art, and implemented as a hardware circuit in the form of a field programmable gate array (FPGA), a complex programmable logic device (CPLD), or an application-specific integrated circuit (ASIC).

[0022] Please refer to Figure 3 , Figure 3 FIG. shows a flowchart of an imaging method of an imaging device according to an embodiment of the present invention. In step S310, the night mode of the imaging device can be activated. In step S320, the infrared (IR) light source 1 is turned on. Then, in step S330, the imaging device can perform a sensing operation on the light intensity of the shooting scene and thereby obtain light intensity information. In step S340, based on the light intensity information, the imaging device can determine whether the light intensity of the shooting scene is too low, and when the imaging device determines that the light intensity of the shooting scene is too low, perform step S350 to turn on the IR light source 2 while maintaining the IR light source 1 being turned on. Among them, in step S340, the imaging device can determine whether the light intensity of the shooting scene is too low according to whether the light intensity information is not greater than a default threshold. And the IR light source 1 and the IR light source 2 can have different light patterns respectively.

[0023] In step S360, the imaging device can continuously sense the light intensity of the shooting scene and obtain dynamically changing light intensity information. In step S370, if the imaging device determines that the light intensity of the shooting scene is too high, in step S380, the IR light source 2 can be turned off while maintaining the IR light source 1 being turned on. Among them, in step S370, the imaging device can determine whether the light intensity of the shooting scene is too high according to whether the light intensity information is greater than another default threshold. The preset threshold in step S340 can be smaller than the other threshold in step S370.

[0024] It is worth mentioning that the above-mentioned threshold can be set by the designer according to the minimum exposure intensity required by the imaging device and the maximum acceptable exposure intensity. Among them, a relatively low threshold is used to ensure that the imaging device can perform the image capture operation with an infrared light intensity above the minimum exposure intensity. A relatively high threshold is used to ensure that the imaging device does not cause overexposure when performing the image capture operation.

[0025] Please refer to the following Figure 4 , Figure 4 which shows a flowchart of another implementation of the image capture method of the imaging device according to an embodiment of the present invention. Among them, in step S410, the night mode of the imaging device can be activated. In step S420, the infrared light (IR) source 1 is turned on. Then, in step S430, the imaging device can perform the operation of capturing image information. In step S440, the imaging device can perform the operation of automatic exposure. In step S450, the imaging device can sense the light intensity information of the shooting scene and determine whether the light intensity information is greater than the threshold A. If in step S450, the imaging device determines that the light intensity information is not greater than the threshold A, step S451 can be executed. On the contrary, if in step S450, the imaging device determines that the light intensity information is greater than the threshold A, step S460 can be executed.

[0026] In step S451, the imaging device can further determine whether the current exposure setting time is the maximum value. If the exposure setting time of the imaging device is the maximum value at this time, step S452 can be executed to determine whether the IR source 2 has been turned on. If the IR source 2 has been turned on, the imaging device can capture the image information in the night mode through step S470. On the contrary, if in step S452, the imaging device determines that the R source 2 has not been turned on, the imaging device can execute step S453 to turn on the IR source 2 and return to step S440.

[0027] Here, please note that the imaging device can adjust the exposure setting time according to the current light intensity of the shooting scene. When the light intensity is relatively low, the imaging device can increase the exposure setting time to increase the exposure amount during image capture. On the contrary, when the light intensity is relatively high, the imaging device can decrease the exposure setting time to increase the exposure amount during image capture.

[0028] On the contrary, if in step S451, the exposure setting time of the imaging device at this time is not the maximum value, it can return to step S440.

[0029] In step S460, the imaging device can determine whether overexposure is likely to occur by judging whether the light intensity of the shooting scene at this time is too high. If in step S460, the imaging device determines that overexposure will not occur, step S470 can be executed to capture the image information in night mode. On the contrary, if in step S460, the imaging device determines that overexposure will occur, then step S461 can be executed.

[0030] In step S461, the imaging device can further determine whether the exposure setting time at this time is the minimum value. If the determination result is yes, the IR light source 2 can be turned off. On the contrary, if the determination result of step S461 is no, the process can return to step S440.

[0031] Please refer to the following Figure 5 , Figure 5 The flowchart of the imaging method showing another embodiment of the present invention. Among them, in step S510, a plurality of infrared light sources are provided, and the infrared light sources respectively have different light types. In step S520, an imaging device is provided to capture image information. And, in step S530, a controller is provided to turn on or off each infrared light source according to the light intensity information, wherein at least one of the infrared light sources is turned on during the imaging operation.

[0032] Regarding the implementation details of the above steps S510 to S530, detailed descriptions have been given in the foregoing embodiments and implementation manners, and will not be elaborated here.

[0033] In summary, the imaging device of the present invention controls the infrared light source to be turned on according to the light intensity of the shooting scene. Thereby, the imaging device can dynamically adjust the on or off state of the infrared light sources with different light types according to the actual situation of the shooting scene, and can effectively improve the quality of the captured image.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An image capturing device, comprising: A plurality of infrared light sources, each having a different variety of light patterns; An image capture unit for capturing image information; And A controller coupled to the plurality of infrared light sources and the image capture unit, the controller turning on or off each of the infrared light sources according to light intensity information, wherein during an image capturing operation, at least one of the plurality of infrared light sources is turned on.

2. The image capturing device according to claim 1, wherein the light beam emission ranges of the plurality of infrared light sources are different.

3. The image capturing device according to claim 2, wherein the plurality of infrared light sources include a first infrared light source and a second infrared light source, and the light beam emission range of the first infrared light source is greater than that of the second infrared light source.

4. The image capturing device according to claim 2, wherein the image capture unit is used to sense the light intensity information, and the controller is configured to: Turn on the first infrared light source; and Turn on the second infrared light source according to the light intensity information.

5. The image capturing device according to claim 4, wherein the controller is further configured to: When the light intensity information is less than a first threshold, turn on the second infrared light source.

6. The image capturing device according to claim 5, wherein the controller is further configured to: When the light intensity information is not less than the first threshold, determine whether the light intensity information is greater than a second threshold; and When the light intensity information is not greater than the second threshold, cause the image capture unit to capture the image information, wherein the first threshold is less than the second threshold.

7. The image capturing device according to claim 6, wherein the controller is further configured to: When the light intensity information is greater than the second threshold, turn off the second infrared light source.

8. An image capturing method, comprising: Providing a plurality of infrared light sources, wherein the plurality of infrared light sources each have a different variety of light patterns; Providing an image capture unit to capture image information; And Providing a controller to turn on or off each of the infrared light sources according to light intensity information, wherein during an image capturing operation, at least one of the plurality of infrared light sources is turned on.

9. The image capturing method according to claim 8, wherein the light beam emission ranges of the plurality of infrared light sources are different.

10. The image capturing method according to claim 8, wherein the plurality of infrared light sources include a first infrared light source and a second infrared light source, and the light beam emission range of the first infrared light source is greater than that of the second infrared light source, and the image capturing method further comprises: Turning on the first infrared light source; And Turning on the second infrared light source according to the light intensity information.

11. The image capturing method according to claim 10, wherein the step of turning on the second infrared light source according to the light intensity information and the exposure setting time comprises: When the light intensity information is less than a first threshold, turn on the second infrared light source.

12. The image capturing method according to claim 11, further comprising: When the light intensity information is not less than the first threshold, determine whether the light intensity information is greater than the second threshold; And When the light intensity information is not greater than the second threshold, cause the image capture device to capture the image information, wherein the first threshold is less than the second threshold.

13. The image capture method according to claim 12, further comprising: When the light intensity information is greater than the second threshold, turn off the second infrared light source.

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