KR20080055548A - Camera acquiring image without shutter lag and method thereof - Google Patents

Abstract

A camera and a method for obtaining an image without a shutter lag are provided to produce/process/store plural image frames by photographing an object and to select an image frame photographed at the shutter release point among the stored plural images. An image sensor unit(110) generates the plural image frames sequentially. An image processing unit(120) processes the plural image frames produced at the image sensor member according to the predetermined image processing manner. A memory unit(130) stores the plural image frames processed by the image processing unit sequentially. When there is a shutter release of a user, a shutter lag calculating unit measures the shutter lag time until the time when the image frame captured by the shutter release is stored in the memory unit from the shutter release time. A memory control unit(150) selects and outputs the image frame stored before the shutter lap time from the storing time of the captured image frame among plural image frames.

Description

CAMERA ACQUIRING IMAGE WITHOUT SHUTTER LAG AND METHOD THEREOF}

1 is a block diagram of a camera according to the prior art.

2 is a block diagram of a camera for obtaining an image without a shutter rack according to an embodiment of the present invention.

3 is a block diagram of a camera for acquiring an image without a shutter rack according to another embodiment of the present invention.

4 is a flowchart illustrating a method of obtaining an image without a shutter rack according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: camera 110: image sensor

120: image processing unit 130: memory unit

140: shutter rack calculation unit 150: control unit

160: shutter 170: display unit

180: image frame selection means

The present invention relates to a camera and a method for acquiring an image without a shutter rack. More particularly, the present invention provides a method of generating / processing / storing a plurality of image frames by capturing a subject even before a shutter release, and storing the plurality of images A camera and a method for obtaining an image without a shutter rack by selecting an image frame photographed at a shutter release time point among frames.

Recently, with the development of digital technology and multimedia technology, digital cameras have become commonplace, and camera modules are mounted on portable devices such as mobile phones and PDAs to support digital camera functions.

1 is a block diagram of a camera according to the prior art.

As shown in FIG. 1, the camera 10 according to the related art includes an image sensor 11 and an image processor 12.

The image sensor unit 11 photographs a subject, generates and outputs an image signal thereof, and the image processor 12 processes an image signal of the subject output from the image sensor unit 11 in a predetermined image process. After processing according to the method, it is outputted.

The image processor 12 determines the position or shutter speed (or exposure time) of the lens of the image sensor unit 11 to generate an image in which focus and exposure are optimal when there is a shutter release of the user. After the adjustment is completed, the image sensor unit 11 photographs the subject. Therefore, a time difference increases from a user's shutter release point to a time point at which the image sensor unit 11 photographs a subject, and the time difference is greatly affected by the photographing environment of the subject. This time difference is called a shutter lag.

According to such a shutter rack, a user may not acquire a desired image even when the user releases the shutter at a desired time.

The present invention is to solve the above-mentioned problems of the prior art, by shooting and storing a plurality of image frames for the subject before the shutter release, by selecting the image frame at the shutter release time of the plurality of stored image frame, There is provided a camera and a method for acquiring an image without this.

In order to achieve the above technical problem, in a camera having a shutter rack after the shutter release until the image frame is generated by the shutter release, an image sensor unit for generating a plurality of image frames sequentially, and in the image sensor unit An image processor that processes the plurality of generated image frames according to a predetermined image processing method, a memory unit that sequentially stores the plurality of image frames processed by the image processor, and the shutter when the user releases the shutter A shutter rack calculation unit for measuring a shutter rack time from a release time point to a time point at which an image frame captured according to the shutter release is stored in the memory unit, and among the plurality of image frames stored in the memory unit, by the shutter release Store before the shutter lag time from the storage point of the captured image frame It provides a camera for selecting the image frame to obtain a non-shutter lag comprises a memory control section for the output image.

In an embodiment of the present invention, the memory controller may delete all the image frames stored in the memory unit after the selection of the image frame.

In an embodiment of the present disclosure, the memory controller may delete the stored image frame first when the image frame stored in the memory unit exceeds a preset memory capacity.

An embodiment of the present invention is characterized by further comprising a display unit for displaying the image frame stored in the memory unit and an image frame selecting unit for selecting the image frame displayed on the display unit.

In addition, an embodiment of the present invention, in the method for acquiring an image with a camera having a shutter rack after the shutter release, until the image frame is generated by the shutter release, the step of generating a plurality of image frames sequentially; Processing the sequentially generated plurality of image frames according to a predetermined image processing method, sequentially storing the processed plurality of image frames, and when the user releases the shutter, from the release time point, the plurality of Measuring a shutter rack time until a point in time at which an image frame generated by the release of the image frames of the image frames is stored in the memory unit; and storing the image frames captured by the shutter release among the plurality of stored image frames. A shutter comprising selecting an image frame stored before the shutter lag time from a viewpoint Provides a method for acquiring rackless images.

Hereinafter, various embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

2 is a block diagram of a camera for obtaining an image without a shutter rack according to an embodiment of the present invention.

2, the camera 100 according to the embodiment of the present invention includes an image sensor unit 110, an image processing unit 120, a memory unit 130, a shutter rack calculation unit 140, and a memory. The controller 150 and the shutter 160 are included.

The image sensor unit 110 includes a lens, an image sensor, and the like to sequentially generate a plurality of image frames.

The image processing unit 120 processes the plurality of image frames from the image sensor unit 110 according to a predetermined image processing method.

The memory unit 130 sequentially stores the plurality of image frames processed by the image processing unit 120.

When there is a shutter release of the user, the shutter rack calculator 140 measures the shutter rack time from the shutter release time point to the time when the image frame captured according to the shutter release is stored in the memory unit.

The memory controller 150 selects and outputs an image frame stored before the shutter rack time from a storage time point of the image frame captured by the shutter release, from among a plurality of image frames stored in the memory unit 130.

Meanwhile, the memory controller 150 may delete all the image frames stored in the memory unit 130 after the selection of the image frame, and the memory controller 150 may be configured to the memory unit 130. When the stored image frame exceeds the preset memory capacity, the stored image frame may be deleted first.

The shutter 160 is a device to which a user inputs a command for photographing a subject.

3 is a block diagram of a camera for acquiring an image without a shutter rack according to another embodiment of the present invention.

The camera 100 ′ shown in FIG. 3 has the same structure as the camera shown in FIG. 2, but is displayed on the display unit 170 and the display unit 170 for displaying an image frame stored in the memory unit 130. The apparatus further includes image frame selecting means 180 for selecting an image frame to be used.

4 is a flowchart of a method for obtaining an image without a shutter rack according to an embodiment of the present invention.

Referring to FIG. 4, in the method of obtaining an image without a shutter rack according to an embodiment of the present invention, the method may include photographing a subject to generate an image frame (S110), and using the image frame according to a predetermined image processing method. Processing (S120), storing the processed image frame (S130), determining whether a user has a shutter release (S140), and when the user releases a shutter, the plurality of images from the release time point. Measuring a shutter rack time until a point in time at which an image frame generated by the release of the frames is stored in the memory unit (S150); and storing the image frame captured by the shutter release among a plurality of stored image frames And selecting and outputting an image frame stored before the shutter rack time from a viewpoint (S160).

Hereinafter, with reference to the accompanying drawings will be described the operation and effect of the embodiment of the present invention.

First, referring to FIG. 2, the image sensor 110 sequentially generates image frames before the shutter release of the user, and supplies the generated image frames to the image processor 120. The camera may be set to a predetermined mode for acquiring an image without a shutter rack. When the camera is set to the mode, the image sensor unit 110 of the camera starts to generate an image frame.

The plurality of image frames generated by the image sensor unit 110 are composed of electrical signals for each pixel in an image sensor such as CMOS provided in the image sensor unit 110. Such a signal may be recognized by a user. It can't be signaled. The image processor 120 processes the signals for the plurality of image frames from the image sensor 110 in a predetermined processing manner and converts the signals into signals that a user can recognize through a display device such as an LCD.

In addition, the signal from the image sensor unit 110 may be affected by defects, external noise, and the like of an image sensor such as a hot pixel or a cold pixel, and the image processor 120 may generate the high quality image. Processing to remove the defect of the image sensor and the influence of external noise can be performed.

In addition, the image processor 120 performs auto focus (AF) and auto exposure (AE) so that the captured image has an optimal focus and an optimal exposure characteristic according to a subject photographing environment. In order to perform this process, a lens or an image sensor of the image sensor 110 is adjusted, whereby the user can obtain an optimal image.

However, while the image sensor unit 110 and the image processing unit 120 operate to obtain an optimal image as described above, a time difference occurs between a shutter release time of the user and a time point at which an image generated by the image is actually taken. This difference is a major factor in generating the shutter rack.

The plurality of image frames processed by the image processor 120 is supplied to the memory unit 130, and the memory unit 130 stores the plurality of image frames.

In this case, the memory unit 130 may store the capturing time of the plurality of image frames for each of the plurality of image frames, or may store a plurality of image frames including information on the capturing time of the corresponding image frame. . Information on the shooting time of the image frame is used to select any one of the image frame stored in the memory unit 130, which will be described later.

Such image frames are continuously generated / processed / stored until the image frames generated by the shutter release operation of the user are stored in the memory unit 130.

On the other hand, the memory unit 130 has a limited storage capacity, and therefore, the number of image frames that can be stored in the memory unit 130 is limited. For example, when using an image sensor of 3 million pixels, a memory capacity of about 3 Mb is required per frame, and when the capacity of the memory unit 130 is 128 Mb, approximately 42 image frames are stored in the memory unit 130. ) Can be stored. That is, in the case of a camera capable of processing 15 frames per second, an image frame of a subject for about 2.8 seconds may be stored in the memory unit 130.

However, after the user operates the camera 100, it may be longer than 2.8 seconds to actually photograph the subject. Therefore, when 2.8 seconds have elapsed after the camera 100 is turned on, the memory unit 130 can no longer store image frames. Therefore, the memory controller 150 stores the image frames sequentially stored in the memory unit 130. When the preset memory capacity of the memory unit 130 is exceeded, first, the stored image frame may be deleted from the memory unit 130 to store the generated image frame.

Through this process, even if the capacity of the memory unit 130 is limited, memory management may be performed in a first input first output (FIFO) manner to obtain an image without a shutter rack without expanding the capacity of the memory unit 130. Can be.

The larger the memory capacity of the memory unit 130 has the advantage of storing more image frames, but in consideration of economics, it may be determined according to the maximum resolution of the camera, the maximum shutter rack time, the maximum frame rate of the camera.

For example, if the maximum resolution of the camera is 3 million pixels (the capacity of one image frame is 3Mb), the maximum shutter lag time is 1.5 seconds, and the maximum frame rate is 15 fps (frame per second), the memory unit 130 The memory capacity of is preferably about 68 Mb (3 x 1.5 x 15) or more.

Next, when the user releases the shutter to photograph the subject, the image sensor unit 110 captures an image frame of the subject by the shutter release operation, and the captured image frame is the image processor 120. Is processed according to the processing method described above and stored in the memory unit 130.

If there is a shutter release operation in this process, as described above, after a predetermined time is required by performing the auto focus, auto exposure, etc. in the image processing unit 120, the subject from the image sensor unit 110 The captured image is captured by the image processing unit 120 and then stored in the memory unit 130.

Accordingly, the time difference between the image frames captured by the shutter 160 release operation and the time stored in the memory unit 130 from the time at which the shutter release operation is performed becomes the shutter rack time. In this case, after the shutter rack time is calculated by the shutter rack calculator 140, the shutter rack time is supplied to the memory controller 150, and the memory controller 150 controls the shutter among a plurality of image frames stored in the memory unit 130. Select the frame stored in the memory unit 130 before the rack time to output.

Since the time that the memory unit 130 receives and stores the image frame from the image processing unit 120 is negligible when compared with the time interval in which the successive image frames are generated, the shutter rack calculator 140 The shutter rack time Δt = from a time point t1 at which the shutter 160 of the camera 100 is released and a time point t2 at which an image frame from the image processing unit 120 is transmitted to the memory unit 130. t2-t1) can be calculated.

Accordingly, among the image frames stored in the memory unit 130, the image frame photographed before the shutter rack time Δt becomes an image frame at a point in time to be captured by the user. There is no video frame.

In this case, as described above, the memory unit 130 may include information about the shooting time of each image frame or each image frame of the memory unit 130 may include information about the shooting time of the corresponding frame. Can be. The image frame photographed at the shutter release time may be automatically selected using the information on the shooting time of each image frame and the shutter rack time Δt.

On the other hand, after selecting one frame among the image frames stored in the memory unit 130, the memory controller 150 deletes all the image frames stored in the memory unit 130, the memory unit 150 Allows a new image frame to be acquired for the subject.

Next, with reference to FIG. 3, the operation of the camera for obtaining an image without a shutter rack according to another embodiment of the present invention will be described.

The camera 100 ′ shown in FIG. 3 has the same structure as the camera 100 shown in FIG. 2, but the display unit 170 and the image frame selecting unit 180 are further added to the camera 100 shown in FIG. 2. Include.

Parallax may occur when the user releases the shutter 160 by looking at the operation of the subject, and may release the shutter when the user does not want to see the desired time point due to a mistake of the user. In this case, even though the memory controller 150 selects one of the image frames stored in the memory 130 according to the processing time from the shutter rack calculator 140, the memory controller 150 selects a desired image. There is a case where it cannot be obtained.

When there is a shutter release of the user, the memory controller 150 displays a plurality of image frames stored in the memory 130 on the display unit 170 such as an LCD, and each image displayed by the user on the display unit 170. Among the frames, a desired image may be selected through the image frame selecting means 180.

For example, when selecting a desired image frame through the display unit 170 and the image frame selecting means 180 every time the subject is taken, it takes a long time for selection, which is inefficient when the user continues to photograph the subject. In this case, the memory controller 150 selects an image frame according to the processing time from the shutter rack calculator 140, and when the photographing interval is sufficiently large, the display unit 170 and the image frame selection means ( 180, an image frame may be selected.

The image frame selecting means 180 may be a button for menu input generally provided to the camera 100 ', and the camera 100' may be provided with a separate button for selecting an image frame. have. In addition to these buttons, the image frame selection means 180 may use a touch screen mounted on the surface of a display device such as an LCD.

Next, a method of obtaining an image without a shutter rack according to an embodiment of the present invention will be described with reference to FIG. 4.

After the shutter release, when the image is captured by the camera with the shutter rack until the image frame is generated by the shutter release, the camera generates an image frame (S110) and processes the generated image frame according to a predetermined image processing method. After (S120), the processed image frame is stored (S130). This process (S110-S130) is repeated until there is a shutter release operation of the user.

If there is a shutter release operation of the user (S140), the time for processing the image frame captured by the camera by the shutter release is measured (S150). Accordingly, the shutter rack time from the user's shutter release time to the time when the image frame is processed and stored is measured.

Next, an image frame stored before the shutter rack time is selected from a storage time point of the image frame captured by the shutter release among the plurality of image frames stored by the shutter release among the stored image frames (S160).

Through the above process, after sequentially storing the image of the subject before releasing the shutter, it is possible to accurately select the image frame at the time of the shutter release, thereby obtaining an image without a shutter rack for the subject.

In addition, when the camera has a predetermined mode (eg, shutter rack removing mode) for acquiring an image without a shutter rack, the method may be performed after the camera is set to the mode.

The present invention is not limited by the above-described embodiment and the accompanying drawings, but by the appended claims. Therefore, it will be apparent to those skilled in the art that various forms of substitution, modification, and alteration are possible without departing from the technical spirit of the present invention described in the claims, and the appended claims. Will belong to the technical spirit described in.

As described above, according to the present invention, there is an effect that can obtain an image without a shutter rack.

In particular, even when the subject moves a lot, there is an effect of obtaining an image photographing the subject at a desired time point.

Claims (5)

An image sensor unit sequentially generating a plurality of image frames; An image processor configured to process the plurality of image frames generated by the image sensor unit according to a predetermined image processing method; A memory unit for sequentially storing a plurality of image frames processed by the image processor; A shutter rack calculator configured to measure a shutter rack time from the shutter release time point to a time point at which an image frame captured according to the shutter release time is stored in the memory unit, when the user releases the shutter; And A memory controller which selects and outputs an image frame stored before the shutter rack time from a storage time point of the image frame captured by the shutter release among a plurality of image frames stored in the memory unit. Camera to obtain an image without a shutter rack comprising a. The method of claim 1, wherein the memory control unit, And after the selection of the image frame, all the image frames stored in the memory unit are deleted. The method of claim 1, wherein the memory control unit, And when the image frame stored in the memory unit exceeds a preset memory capacity, first deleting the stored image frame. The method of claim 1, A display unit which displays an image frame stored in the memory unit; And Image frame selection means for selecting an image frame displayed on the display unit The camera to obtain an image without a shutter rack further comprising. Sequentially generating a plurality of image frames; Processing the plurality of sequentially generated image frames according to a predetermined image processing method; Sequentially storing the processed plurality of image frames; If there is a shutter release of a user, measuring a shutter rack time from the shutter release time point to a time point at which an image frame captured according to the shutter release is stored in the memory unit; And Selecting and outputting an image frame stored before the shutter rack time from a storage time point of the image frame captured by the shutter release among a plurality of image frames stored in the memory unit; How to obtain an image without a shutter rack comprising a.

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