TWI385475B - Image pick-up device and flash control method thereof - Google Patents

Description

Image capturing device and flash control method thereof

The invention relates to an image capturing device and a flash control method thereof.

At present, image capturing devices such as digital cameras often have an electronic flash to compensate for the brightness of the subject under low light conditions. Electronic flash control methods include automatic and manual. The automatic type generally automatically measures the distance between a target and the image capturing device by means of an automatic ranging module or flash pre-flashing, and automatically controls the flashing intensity of the flash according to the aperture value of the image capturing device. Manual mode is the flash intensity of the flash set by the photographer. However, an inexperienced photographer often misjudges the distance between the subject and the image capturing device, and does not know enough about the range of illumination corresponding to the flash intensity of the flash. Therefore, it is often easy to select the wrong flash intensity, resulting in overexposure or Underexposed.

In view of this, it is necessary to provide an image capturing device capable of displaying a range of scenes illuminated by a flash and a flash control method thereof.

An image capturing device includes an imaging module, a flash module, a central processing module and a human machine interface. The imaging module is configured to sense an external scene, form an image signal, and transmit the image signal to the central processing module. The flash module is used to flash when shooting to compensate for the brightness of the subject. The central processing module is configured to process image signals from the imaging module, and output the processed image signals to the human-machine interface, and display at least two presets on the human-machine interface The flash distance is selected by the photographer, and when the photographer selects one of the preset flash distances, the range of the scene that the flash module can illuminate under the preset flash distance is displayed on the human machine interface. The central processing module controls the flash module to flash when shooting according to a preset flash distance selected by the photographer.

A flash control method applied to an image capture device, the image capture device comprising a flash module, the flash control method comprising the steps of: sensing a scene, obtaining and previewing an image of the scene; providing at least two The preset flash distance is selected by the photographer; according to the preset flash distance selected by the photographer, the range of the scene that can be illuminated by the flash module is displayed; and the flash module is controlled according to the preset flash distance selected by the photographer. Flash and shoot the scene.

Compared with the prior art, the image capturing device and the flash control method thereof allow the photographer to select the flash distance of the flash module and display the range of the scene that can be illuminated by the flash module under the flash distance. It is easy for the photographer to select a suitable flash distance for better exposure.

The following preferred embodiments will be described in detail below with reference to the accompanying drawings.

Please refer to FIG. 1 and FIG. 2, which are the image capturing device 1 of the present invention. The image The capture device 1 includes an imaging module 10, a flash module 20, an automatic ranging module 30, a central processing module 40, a human interface 50, and a storage module 60.

The imaging module 10 is configured to sense an external scene, form an image signal, and transmit the image signal to the central processing module 40. The imaging module 10 can be a lens and an image sensor.

The flash module 20 is used to flash when shooting to compensate for the brightness of the subject. The flash module 20 has a maximum flash distance determined by the performance of the flash module 20 itself. The flash module 20 can be a flash system.

The automatic ranging module 30 is configured to obtain a distance between the scene in the image sensed by the imaging module 10 and the image capturing device 1 , and provide the result to the central processing module 40 . Preferably, the automatic ranging module 30 first selects at least two reference objects in the scene, and measures a distance between the at least two reference objects and the image capturing device 1, and then according to the at least two Positioning of the reference object in the image, determining a projection relationship between the scene and the image, and then according to a positional relationship between the other scenes and the at least two reference objects in the image, and a projection relationship between the scene and the image, The distance between other scenes in the image and the image capturing device 1 is calculated. The automatic ranging module 30 is a built-in range finder.

The central processing module 40 includes an image processing unit 42 and a control unit 44.

The image processing unit 42 is configured to process image signals from the imaging module 10 and store the processed image signals in the storage module 60. At the same time, it is output to the human machine interface 50 at the same time.

The control unit 44 is configured to display at least two preset flash distances on the human machine interface 50 for the photographer to select, and when the photographer selects one of the preset flash distances, the control unit 44 according to the preset The illumination range corresponding to the flash module 20 and the distance between the scene in the image and the image capturing device 1 are displayed on the human interface 50 at the preset flash distance. The range of the scene that the flash module 20 can illuminate to indicate whether the target object of the photographer can be illuminated by the flash module 20. The optional preset flash distance may be any value from 0 to the maximum flash distance of the flash module 20, and the illumination range of the flash module 20 corresponding to each preset flash distance is preset.

The control unit 44 can be configured according to the distance between the scene in the image provided by the automatic ranging module 30 and the image capturing device 1 and the flash module corresponding to the preset flash distance selected by the photographer. The illumination range of 20, finds the scene located in the illumination range, and changes the brightness of the corresponding pixel point of the scene in the illumination range on the human interface 50 to display the flash module 20 The range of scenery that can be illuminated. Preferably, the control unit 44 forms a brightness-increasing area on the human-machine interface 50 by increasing the brightness of the corresponding pixel point of the scene in the illumination range on the human-machine interface 50. The range of scenes that the flash module 20 can illuminate. The control unit 44 can also increase the brightness of the corresponding pixel point of the scene located on the edge of the illumination range on the human interface 50 to form an auxiliary line surrounding the scene in the illumination range, so as to prompt the photographer to be The flash module 20 illuminates the range of scenery.

When the photographer performs shooting, the control unit 44 controls the flash module 20 to perform flashing according to the preset flash distance selected by the photographer. Wherein, when the preset preset flash distance is 0, the flash module 20 does not flash. The central processing unit 40 includes a digital signal processor, an automatic gain controller, an analog to digital converter, and the like.

The human interface 50 is configured to convert the signal from the central processing module 40 into an image visible by the photographer, and input the preset flash distance selected by the photographer to the central processing module 40 according to the operation of the photographer. . The human interface 50 can be a display and a button or touch mode liquid crystal display.

The storage module 60 is configured to store image signals from the central processing module 40. The storage module 60 can be a memory.

Please refer to FIG. 3 , which is a flash control method applied to the image capturing device 1 described above. The flash control method includes the following steps:

S100: Sensing a scene, obtaining and previewing an image of the scene. In this step, the imaging module 10 senses the scene and obtains an image, and then previews the image on the human interface 50.

S101: Obtain a distance between the scene in the image and the image capturing device 1. In this step, the automatic ranging module 30 first selects at least two reference objects in the scene, and measures the distance between the at least two reference objects and the image capturing device 1, and then according to Positioning the at least two reference objects in the image to determine a projection relationship between the scene and the image, and then according to a positional relationship between the other scenes and the at least two reference objects in the image and the scene and the image Projection relationship, calculate this The distance between other scenes in the image and the image capturing device 1.

S102: Provide at least two preset flash distances for the photographer to select. In this step, the control unit 44 displays at least two preset flash distances on the human machine interface 50.

S103: Display a range of scenes that can be illuminated by the flash module 20 according to a preset flash distance selected by the photographer. In this step, according to the distance between the scene in the image and the image capturing device 1, and the illumination range of the flash module 20 corresponding to the preset flash distance selected by the photographer, A scene located within the illuminated range and displaying a range of scenes that can be illuminated by the flash module 20. In this step, the control unit 44 finds a scene located within the illumination range and displays it on the human machine interface 50.

S104: Determine whether the flash is performed by using the preset flash distance. If yes, proceed to step S105, and if no, proceed to step S102. In this step, the control unit 44 makes a determination based on the photographer's operation on the human machine interface 50.

S105: Control the flash module 20 to perform flash according to a preset flash distance selected by the photographer, and capture the scene. In this step, the flash module 20 is controlled by the control unit 44.

Compared with the prior art, the image capturing device and the flash control method thereof allow the photographer to select the flash distance of the flash module and display the range of the scene that can be illuminated by the flash module under the flash distance. It is easy for the photographer to select a suitable flash distance for better exposure.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. However, the above description is only the preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and equivalent modifications or variations made by those skilled in the art in light of the spirit of the present invention are It should be covered by the following patent application.

1‧‧‧Image capture device

10‧‧‧ imaging module

20‧‧‧Flash Module

30‧‧‧Automatic distance measuring module

40‧‧‧Central Processing Module

42‧‧‧Image Processing Unit

44‧‧‧Control unit

50‧‧‧Human Machine Interface

60‧‧‧Memory Module

1 is a functional block diagram of an image capture device of the present invention.

2 is a schematic view showing the working state of the image capturing device of FIG. 1.

3 is a flow chart of a flash control method using the image capture device of FIG. 1.

1‧‧‧Image capture device

10‧‧‧ imaging module

20‧‧‧Flash Module

30‧‧‧Automatic distance measuring module

40‧‧‧Central Processing Module

42‧‧‧Image Processing Unit

44‧‧‧Control unit

50‧‧‧Human Machine Interface

60‧‧‧Memory Module

Claims (8)

An image capturing device includes an imaging module, a flash module, a central processing module and a human machine interface, wherein the imaging module is configured to sense an external scene, form an image signal, and transmit the image signal To the central processing module, the flash module is configured to flash during shooting to compensate for brightness of the subject, wherein the central processing module is configured to process image signals from the imaging module, and The processed image signal is output to the human machine interface, and at least two preset flash distances are displayed on the human machine interface for the photographer to select, and when the photographer selects one of the preset flash distances, the person The machine interface displays a range of scenes that the flash module can illuminate under the preset flash distance, and the central processing module controls the flash module to flash when shooting according to a preset flash distance selected by a photographer. The image capturing device further includes an automatic ranging module, wherein the automatic ranging module is configured to select at least two reference objects in the scene, and measure the at least two reference objects and the And determining a projection relationship between the scene and the image according to the position of the at least two reference objects in the image, and then according to the other scenes in the image and the at least two reference objects The positional relationship between the scene and the projection relationship between the scene and the image calculates the distance between other scenes in the image and the image capturing device. The image capturing device of the first aspect of the invention, wherein the central processing module is based on a distance between a scene in the image provided by the automatic ranging module and the image capturing device, and The illumination range of the flash module corresponding to the preset flash distance selected by the photographer, finding a scene located in the illumination range, and changing the scene located in the illumination range to correspond to the human-machine interface The brightness of the pixel points to display the flash module The range of scenery that can be illuminated. The image capture device of claim 2, wherein the central processing module increases the brightness of a pixel corresponding to the scene in the illumination range on the human-machine interface to A highlight area is formed on the human-machine interface for indicating a range of scenes that the flash module can illuminate. The image capture device of claim 2, wherein the central processing module increases the brightness of a pixel point corresponding to a scene located at an edge of the illumination range on the human-machine interface to form a An auxiliary line enclosing the scene located within the illumination range for prompting the photographer of the range of scenery that can be illuminated by the flash module. The image capturing device of the second aspect of the invention, wherein the illumination range of the flash module corresponding to the preset flash distance is preset. A flash control method for an image capture device, the image capture device comprising a flash module, the flash control method comprising the steps of: sensing a scene, obtaining and previewing an image of the scene; Selecting at least two reference objects in the scene, and measuring a distance between the at least two reference objects and the image capturing device, and then determining the scene according to the position of the at least two reference objects in the image According to the projection relationship of the image, according to the positional relationship between the other scenes in the image and the at least two reference objects, and the projection relationship between the scene and the image, the other scenes in the image and the image capturing device are calculated. The distance is provided; at least two preset flash distances are provided for the photographer to select; according to the preset flash distance selected by the photographer, the range of the scene that can be illuminated by the flash module is displayed; according to the preset flash distance selected by the photographer, Controlling the flash module Flash and shoot the scene. The flash control method of claim 6, wherein in the step of displaying a range of the subject that can be illuminated by the flash module according to a preset flash distance selected by the photographer, according to the image The distance between the scene and the image capturing device, and the illumination range of the flash module corresponding to the preset flash distance selected by the photographer, find a scene located in the illumination range, and display the The range of scenes illuminated by the flash module. The flash control method of claim 7, wherein after the step of displaying the range of the scene that can be illuminated by the flash module according to the preset flash distance selected by the photographer, the method further includes determining whether The currently selected preset flash distance is a step of flashing, and if so, controlling the flash module to flash according to a preset flash distance selected by the photographer, and shooting the scene, if not, returning to provide at least two pre- Set the flash distance for the photographer to choose.