JP2006094202A - Imaging apparatus, focusing processing method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus whereby everyone can simply focus a desired part and photographs an object. <P>SOLUTION: In the imaging apparatus provided with a CCD 23 for imaging an object and a display section 19 for displaying image data of the object obtained by the CCD 23 as a through-image, a plurality of optional parts are designated on a screen of the display section 19 as a focus object area. A control section 32 calculates a focus evaluation value on the basis of image data corresponding to the focus object area and focuses each focus object area on the basis of the calculated focus evaluation value as its control. Thus, the user focuses the designated part to carry out photographing without the need for troublesome operations of matching the object with a predetermined position (e.g., a center of the screen). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an imaging apparatus such as a digital camera, and more particularly to an imaging apparatus having an AF (automatic focusing) function, and a focusing processing method and program used for the imaging apparatus.

For example, some imaging devices such as digital cameras have an AF function (automatic focusing function) that automatically focuses on a subject. This AF function operates by half-pressing the shutter key, moves the focus lens, and focuses, for example, on the center portion of the screen. At that time, a focus frame is generally displayed at the center of the screen so that the user is informed of the focused portion (see, for example, Patent Document 1).
JP 2000-92354 A

  As described above, in an imaging apparatus equipped with an AF function, a subject can be focused and photographed by simply pressing the shutter key halfway. However, since the position to focus on is determined in advance, it is necessary to perform troublesome operations such as first taking the subject and then composing and shooting, and it is difficult for users who are unfamiliar with the camera to handle it. was there.

  The present invention has been made in view of the above points, and an object thereof is to provide an imaging apparatus, a focusing processing method, and a program that enable anyone to easily focus and focus on a desired location. .

  An imaging apparatus according to a first aspect of the present invention includes an imaging unit for imaging a subject, a display unit for displaying image data of the subject obtained by the imaging unit as a through image, and a through image displayed by the display unit. An evaluation value for calculating a focus evaluation value based on image data corresponding to the plurality of focus target areas specified by the specification means, and a specifying means for specifying any of a plurality of portions in the focus target area The calculation means and a control means for focusing on each focus target area based on the focus evaluation value calculated by the evaluation value calculation means.

  According to such a configuration, by designating an arbitrary plurality of portions in the through image as the in-focus target area, it is possible to shoot with focusing on the in-focus target area.

  According to a second aspect of the present invention, in the image pickup apparatus according to the first aspect, the control unit switches to pan focus when the focus target areas are not in focus.

  According to such a configuration, when focus is not achieved on each focus target area, it is possible to switch to pan focus and shoot.

  According to a third aspect of the present invention, in the imaging apparatus according to the first aspect, a color detection unit that detects a color of a focused portion from the through image, and a color detected by the color detection unit. And color display means for displaying in a predetermined format.

  According to such a configuration, since the color of the in-focus portion is detected and displayed in, for example, a window format, it is possible to grasp where the focus is in focus from the displayed color.

  According to a fourth aspect of the present invention, in the imaging apparatus according to the first aspect, an image extracting unit that extracts an image of a focused portion from the through image, and an image extracted by the image extracting unit. And image display means for displaying in a predetermined format.

  According to such a configuration, an in-focus image is extracted and displayed in, for example, a window format, so it is possible to grasp where the image is in focus from the displayed image.

  An imaging apparatus according to a fifth aspect of the present invention includes an imaging unit that images a subject, a display unit that displays image data of the subject obtained by the imaging unit as a through image, and a designation unit that specifies an arbitrary color. A focus target setting means for detecting a portion having a color designated by the designation means in the through image displayed by the display means and setting the corresponding portion as a focus target area; and the focus target And a control means for focusing on the focus target area set by the setting means.

  According to such a configuration, by designating an arbitrary color, a portion having the designated color can be set as an in-focus target area, and the in-focus target area can be focused and photographed.

  According to a sixth aspect of the present invention, in the imaging apparatus according to the fifth aspect, the focus target area set by the focus target setting unit is deleted, or another portion is set as the focus target area. It is characterized by comprising a focusing object changing means to be added.

  According to such a configuration, when the focus target area is set based on the color designated by the user, the focus target area is deleted or another part is added as the focus target area. be able to.

  According to a seventh aspect of the present invention, in the imaging apparatus according to the fifth aspect, a color detection unit that detects a color of a focused portion from the through image, and a color detected by the color detection unit. And color display means for displaying in a predetermined format.

  According to such a configuration, since the color of the in-focus portion is detected and displayed in, for example, a window format, it is possible to grasp where the focus is in focus from the displayed color.

  According to an eighth aspect of the present invention, in the imaging apparatus according to the fifth aspect, an image extracting unit that extracts an image of a focused portion from the through image, and an image extracted by the image extracting unit. And image display means for displaying in a predetermined format.

  According to such a configuration, an in-focus image is extracted and displayed in, for example, a window format, so it is possible to grasp where the image is in focus from the displayed image.

  A focusing processing method according to claim 9 of the present invention is used in an imaging apparatus including an imaging device that captures an image of a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image. A focus processing method, the step of designating an arbitrary plurality of portions in a through image displayed on the display unit as a focus target area, and image data corresponding to the plurality of designated focus target areas And a step of calculating a focus evaluation value based on the above and a step of focusing on each focus target area based on the calculated focus evaluation value.

  According to such a focusing processing method, the same effect as that of the first aspect of the invention can be achieved by executing the processing according to each of the steps.

  According to a tenth aspect of the present invention, there is provided a focusing processing method used in an imaging device including an imaging device that captures an image of a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image. A focus processing method for specifying an arbitrary color and detecting a portion having the specified color in a through image displayed on the display unit and setting the corresponding portion as a focus target area And a step of focusing on the set focus target area.

  According to such a focusing processing method, the same effects as those of the invention of the fifth aspect can be achieved by executing the processing according to each step.

  A program according to an eleventh aspect of the present invention is used in a computer that controls an imaging apparatus that includes an imaging device that images a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image. A program that has a function of designating a plurality of portions in a through image displayed on the display unit as a focus target area on the computer, and a function corresponding to the designated focus target areas. A function of calculating a focus evaluation value based on image data and a function of focusing on each focus target area based on the calculated focus evaluation value are realized.

  Therefore, when the computer executes the program for realizing each function, the same effects as those of the first aspect of the invention can be achieved.

  A program according to a twelfth aspect of the present invention is used in a computer that controls an imaging apparatus that includes an imaging device that captures an image of a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image. A program for detecting a portion having the designated color in a through image displayed on the display unit and a function for designating an arbitrary color on the computer, and detecting the corresponding portion as an in-focus area And a function for focusing on the set focus target area.

  Therefore, when the computer executes the program for realizing each function, the same effect as that of the invention of claim 5 can be obtained.

  According to the present invention, an arbitrary plurality of portions on the screen can be designated as the focus target area. Therefore, it is possible to perform photographing while focusing on these designated portions without performing a troublesome operation such as aligning the subject to a predetermined position (for example, the center of the screen).

  In addition, by designating an arbitrary color, a portion having the designated color can be set as a focus target area. Accordingly, it is possible to perform shooting while focusing on a portion having a designated color without performing a troublesome operation such as adjusting the subject to a predetermined position (for example, the center of the screen).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram showing an external configuration when a digital camera is taken as an example of the imaging apparatus according to the first embodiment of the present invention. FIG. 1 (a) is mainly a front configuration, and FIG. It is a perspective view which mainly shows the structure of a back surface.

  The digital camera 1 has a photographing lens 3, a self-timer lamp 4, an optical finder window 5, a strobe light emitting unit 6, a microphone unit 7 and the like on the front surface of a substantially rectangular thin plate-like body 2 on the upper surface (for the user). On the right end side, a power key 8 and a shutter key 9 are provided.

  The power key 8 is a key operated every time the power is turned on / off, and the shutter key 9 is a key for instructing a photographing timing at the time of photographing.

  Also, on the back of the digital camera 1, a shooting mode (R) key 10, a playback mode (P) key 11, an optical viewfinder 12, a speaker unit 13, a macro key 14, a strobe key 15, a menu (MENU) key 16, a ring A key 17, a set (SET) key 18, a display unit 19, and the like are provided.

  The shooting mode key 10 is operated automatically from the power-off state to automatically turn on the power and shift to the still image shooting mode. On the other hand, by repeatedly operating from the power-on state, the still image mode and the moving image mode are switched. Set cyclically. The still image mode is a mode for photographing a still image. The moving image mode is a mode for shooting a moving image.

  The shutter key 9 is commonly used for these photographing modes. That is, in the still image mode, a still image is taken at the timing when the shutter key 9 is pressed. In the moving image mode, shooting of a moving image is started at a timing when the shutter key 9 is pressed, and shooting of the moving image is ended when the shutter key 9 is pressed again.

  When the playback mode key 11 is operated from the power-off state, the playback mode key 11 is automatically turned on to enter the playback mode.

  The macro key 14 is operated when switching between normal shooting and macro shooting in the still image shooting mode. The strobe key 15 is operated when switching the light emission mode of the strobe light emitting unit 6. The menu key 16 is operated when selecting various menu items. The ring key 17 is integrally formed with item selection keys in the up, down, left, and right directions, and the set key 18 located in the center of the ring key 17 sets the item selected at that time. To operate.

  The display unit 19 is composed of a color liquid crystal panel with a backlight, and displays a through image on the monitor as an electronic viewfinder in the photographing mode, and reproduces and displays the selected image and the like in the reproduction mode.

  Although not shown, the digital camera 1 has a memory card slot for attaching / detaching a memory card used as a recording medium, a serial interface connector for connecting to an external personal computer, etc., for example, USB (Universal). (Serial Bus) connector and the like are provided.

  FIG. 2 is a block diagram showing an electronic circuit configuration of the digital camera 1.

  In the digital camera 1, a lens optical system 22 including a focus lens and a zoom lens (not shown) constituting the photographing lens 3 is provided so as to be movable within a predetermined range in the optical axis direction by driving a motor 21. A CCD 23, which is an image sensor, is disposed behind the optical axis. The CCD 23 receives light passing through the photographing lens 3 and acquires image data corresponding to the amount of received light.

  In the recording mode, which is the basic mode, the CCD 23 is scanned and driven by a timing generator (TG) 24 and a driver 25, and outputs a photoelectric conversion output corresponding to a light image formed at regular intervals for one screen.

  The photoelectric conversion output of the CCD 23 is appropriately gain-adjusted for each primary color component of RGB in the state of an analog value signal, sampled and held by the sample hold circuit 26, and converted into digital data by the A / D converter 27. The In the color process circuit 28, color process processing including pixel interpolation processing and γ correction processing is performed to generate digital luminance signals Y and color difference signals Cb, Cr, which are sent to a DMA (Direct Memory Access) controller 29. Is output.

  The DMA controller 29 once uses the luminance signal Y and the color difference signals Cb and Cr output from the color process circuit 28 by using the composite synchronization signal, memory write enable signal, and clock signal from the color process circuit 28 once. And the DMA transfer to the DRAM 31 used as the buffer memory via the DRAM interface (I / F) 30.

  The control unit 32 includes a microcomputer including a CPU 32a, a ROM 32b that stores an operation program executed by the CPU 32a, a RAM 32c used as a work memory, and the like. The control unit 32 controls the entire digital camera 1, and after the DMA transfer of the luminance and color difference signals to the DRAM 31 is completed, the luminance and color difference signals are read from the DRAM 31 via the DRAM interface 30 and the VRAM controller 33 is read. To the VRAM 34.

  The digital video encoder 35 periodically reads the luminance and color difference signals from the VRAM 34 via the VRAM controller 33, generates a video signal based on these data, and outputs the video signal to the display unit 19.

  As described above, the display unit 19 functions as a monitor display unit (electronic finder) at the time of shooting. By performing display based on the video signal from the digital video encoder 35, the display unit 19 captures from the VRAM controller 33 at that time. An image based on the image information is displayed in real time.

  As described above, when the image at that time is displayed in real time as the monitor image on the display unit 19, for example, when the shutter key 9 is pressed at a timing at which still image shooting is desired, a trigger signal is generated.

  In response to the trigger signal, the control unit 32 immediately stops the path from the CCD 23 to the DRAM 31 immediately after the DMA transfer of the luminance and color difference signals for one screen captured from the CCD 23 to the DRAM 31 is completed. , Transition to the record storage state.

  In this recording and storage state, the control unit 32 outputs the luminance and color difference signals for one frame written in the DRAM 31 to 8 pixels × 8 pixels for each of Y, Cb, and Cr components via the DRAM interface 30. The data is read out in units called basic blocks, written in a JPEG (Joint Photographic Coding Experts Group) processing block existing in the image processing unit 37, and the image processing unit 37 uses ADCT (Adaptive Discrete Cosine Transform: adaptive discrete cosine transform). ), The data is compressed by a process such as Huffman coding, which is an entropy coding method.

  The obtained code data is read out from the image processing unit 37 as a data file of one image and written in the recording memory 38. The memory 38 includes a memory card that is detachably mounted as a recording medium in addition to an internal memory such as a flash memory built in the main body in advance. With the compression processing of the luminance and color difference signals for one frame and the completion of writing all the compressed data to the memory 38, the control unit 32 activates the path from the CCD 23 to the DRAM 31 again.

  The control unit 32 is further connected with an audio processing unit 39, a USB interface (I / F) 40, a strobe driving unit 41, and a movement detection unit 42.

  The audio processing unit 39 performs input / output processing of audio data including A / D conversion and D / A conversion. When shooting a moving image, the analog processing unit 39 receives an analog input from the microphone unit (MIC) 7 in synchronization with the moving image data. Digitally capture audio signals. At the time of reproduction, the audio data separated from the moving image data with audio is converted into analog data and output through a speaker unit (SP) 13 provided on the back side of the digital camera 1.

  The USB interface 40 performs communication control when image data and other information are transmitted / received to / from another information terminal device such as a personal computer connected by wire via a USB connector. The strobe drive unit 41 charges a strobe capacitor (not shown) at the time of shooting, and then drives the strobe light emitting unit 6 to flash based on control from the control unit 32.

  The movement detection unit 42 includes, for example, a three-axis acceleration sensor and detects a movement distance when the apparatus main body is moved in an arbitrary direction during photographing. The movement distance detected by the movement detection unit 42 is used for a focus frame display process described later.

  In addition to the shutter key 9 described above, the key input unit 36 includes a power key 8, a shooting mode key 10, a playback mode key 11, a macro key 14, a strobe key 15, a menu key 16, a ring key 17, and a set key. 18 and the like, and signals accompanying these key operations are sent directly to the control unit 32.

  Further, when shooting a moving image instead of a still image, the moving picture processing group (MPEG) or motion is a moving image processing block existing in the image processing unit 37 described above when the shutter key 9 is pressed. -Captured moving image data is compressed and recorded in the memory 38 by a method such as JPEG (Joint Photographic Experts Group). When the shutter key 9 is operated again, the recording of the moving image data is finished.

  On the other hand, in the playback mode, which is the basic mode, the control unit 32 selectively reads out the image data recorded in the memory 38, and the image processing unit 37 compresses the image data in a procedure that is completely opposite to the procedure of data compression in the recording mode. Decompress the image data. The decompressed image data is held in the DRAM 31 via the DRAM interface 30, and then the content held in the DRAM 31 is stored in the VRAM 34 via the VRAM controller 33. The image data is periodically read out from the VRAM 34. A video signal is generated and reproduced and output by the display unit 19.

  If the selected image data is not a still image but a moving image, the multiple frames of still image data that make up the moving image data are played back and displayed sequentially in chronological order, and all the still image data is played back. For example, the top still image data is displayed until the next playback instruction is given.

  Next, the operation of the first embodiment will be described.

  Note that the processing shown in the following flowcharts is executed when the control unit 32 (CPU 32a), which is a microprocessor, reads a program stored in the ROM 32b or the like. The same applies to processing relating to other embodiments, and is executed by the control unit 32 (CPU 32a) reading a program for realizing the embodiment.

  FIG. 3 is a flowchart showing a processing operation at the time of photographing by the digital camera 1 in the first embodiment.

  When the still image shooting mode is set by operating the shooting mode key 10 provided in the digital camera 1 after the power is turned on, the image of the subject is captured through the lens optical system 22 and the CCD 23, and after undergoing a predetermined color process. The through image is displayed on the screen of the display unit 19 (step A11).

  Here, as shown in FIG. 8, when the user designates an arbitrary plurality of portions in the through image 50 displayed on the screen of the display unit 19 as the focus target area (step A12), the control unit 32 ( The CPU 32a) displays focus frames 51 to 53 of a predetermined size in these designated areas (step A13).

  As a method for specifying the focus target area, for example, if a transparent touch panel is mounted on the screen of the display unit 19, a method of directly touching an arbitrary position on the screen with a finger or a pen, or a cursor key operation There is a method such as designating an arbitrary position on the screen. In the example of FIG. 8, three places are designated as the focus target areas, and focus frames 51 to 53 indicating the focus target areas are displayed at the designated places.

  In this state, when the user gives a focus instruction by half-pressing the shutter key 9 (Yes in Step A14), the control unit 32 performs AF processing (automatic focus on the plurality of designated focus target areas. Focusing process) is executed (step A15). The AF process (automatic focusing process) will be described in detail later with reference to FIGS.

  Subsequently, the control unit 32 executes a focus display process for displaying the focused image and color as shown in FIG. 9 (step A16). The focus display process will be described later. This will be described with reference to FIG.

  Here, when the user gives a shooting instruction by pressing the shutter key 9 (Yes in step A17), the control unit 32 executes a predetermined shooting process to capture the currently displayed through image as a still image. Then, it is compressed by a predetermined method and recorded in the memory 38 (step A18). The photographing process has been described in detail with reference to FIG.

(Automatic focusing process)
Next, the automatic focusing process executed in step A15 will be described assuming a contrast detection method.

  As shown in FIG. 10, the contrast detection method is a position where the contrast (high frequency component) of image data is detected while moving the focus lens 22a included in the lens optical system 22 on the optical axis, and the contrast becomes the largest. Is detected as the position where the pit is aligned, that is, the in-focus position.

  Normally, the above processing is performed for image data corresponding to a predetermined area such as the center of the screen (this is called an image block), but here the same processing is performed for a plurality of designated areas. The focus position is detected.

  FIG. 4 is a flowchart showing the overall flow of the automatic focusing process.

  First, the control unit 32 drives the motor 21 to move the focus lens to one end on the optical axis (step B11), and detects a high-frequency component of image data obtained at a predetermined position such as the center of the screen. (Step B12). And the control part 32 determines whether it is the maximum value by comparing the value of this detected high frequency component with the high frequency component detected in another lens position (step B13), and is determined as the maximum value. If so, the value is stored in a predetermined area of the RAM 32c (step B14).

  Specifically, it is assumed that the focus lens 22a is movable between P0 to P6 as shown in FIG. First, the focus lens 22a is moved to the position of P0 at one end thereof, and the value f0 of the high frequency component obtained there is detected. The detected high-frequency component value f0 is compared with the high-frequency component values detected at other lens positions to determine whether or not it is the highest value. In this case, since there is only the high-frequency component value f0 obtained at the position P0 at first, f0 is set as the maximum value.

  Subsequently, the control unit 32 moves the focus lens 22a to the position P1 (step B15 → B16), and detects the high-frequency component value f1 of the image data obtained there (step B12). Then, the control unit 32 compares the detected high-frequency component value f1 with the high-frequency component value f0 that is currently set as the maximum value (step B13). If f1 is greater than f0, the control unit 32 sets f1. Is reset as a new maximum value (step B14). If f1 is smaller than f0, the previous f0 is held as the maximum value.

  In this way, while moving the focus lens 22a one unit at a time from one end (P0) to the opposite end (P6), the value of the high-frequency component obtained at that position and the high-frequency component currently set as the maximum value are obtained. In comparison, the highest value of the high-frequency component obtained at the predetermined position (for example, the center of the screen) is obtained. The maximum value of this high frequency component is set to fmax, and based on this, the focus evaluation value in each designated area is calculated as follows.

  That is, the control unit 32 calculates evaluation values for a plurality of focus target areas designated by the user while moving the focus lens 22a from the opposite end (P6) to the one end (P0) in the reverse direction one unit at a time.

  Now, let the plurality of focus target areas designated by the user be E1 to E3. In the example of FIG. 8, areas where the focus frames 51 to 53 are displayed correspond to E1 to E3. First, the control unit 32 detects the value of the high-frequency component of the image data obtained in the focusing target areas E1 to E3 with the focus lens 22a at the opposite end P6 (step B17).

  And the control part 32 calculates the evaluation value of each focusing object area E1-E3 according to the following formula | equation (1) (step B18), respectively, and the calculated evaluation value is put into the evaluation table 57 shown in FIG. Store (step B19). The evaluation table 57 is provided in a predetermined area of the RAM 32c, for example.

Evaluation value = (SEn / fmax) × 100 (%) (1)
SEn: Value of the high frequency component of the focusing target area En (n is an integer of 1 or more)
fmax: value of the high-frequency component at the predetermined position For example, when the value of the high-frequency component at the predetermined position (center of the screen) is fmax = 100, the value of the high-frequency component in the focusing target area E1 is SE1 = 80. In this case, the evaluation value is obtained as 80. Similarly, if the high-frequency component value SE2 = 60 in the focusing target area E2 and the high-frequency component value SE3 = 50 in the focusing target area E3, the evaluation values of these areas are obtained as 60 and 50, respectively.

  Similarly, while moving the focus lens 22a one unit at a time in the opposite direction from the opposite end (P6) to the one end (P0) (step B20 → B21), the value SEn and the maximum value of the high frequency component obtained at that position Based on fmax, the evaluation values of the focusing target areas E1 to E3 are obtained, and the values are set in the evaluation table 57.

  When the focus lens 22a returns to the position P0 and evaluation values corresponding to the respective positions P0 to P6 are obtained in the evaluation table 57 for the respective focus target areas E1 to E3, the control unit 32 sets the evaluation table 57. A focus determination process is performed based on each evaluation value (step B22), and the focus lens 22a is moved to the focus position determined by the focus determination process (step B23).

  Here, two methods for focusing determination will be described.

(First method)
FIG. 5 is a flowchart showing the focus determination process executed in step B22 and the focus determination process according to the first method.

  First, the control unit 32 reads the evaluation values of the focusing target areas E1 to E3 corresponding to the position P0 in the evaluation table 57, and obtains the total value by adding these evaluation values (step C11). . For example, as shown in FIG. 11, if the evaluation values of the focusing target areas E1 to E3 corresponding to the position of P0 are 80, 60, and 50, the total value is obtained as 190. Similarly, the other positions P1 to P6 are similarly calculated by adding the evaluation values of the focusing target areas E1 to E3.

  Thus, when the total value of each evaluation value is obtained for all the positions P0 to P6 (Yes in Step C12), the control unit 32 detects the one having the highest total value from these (Step C13). ). If the detected total value is equal to or greater than the predetermined value (Yes in step C14), the control unit 32 determines that each focusing target area E1 to E3 is in focus, and determines the lens position (total value). Is determined as the in-focus position (step C15).

  On the other hand, if the detected total value is less than the predetermined value (No in Step C14), the control unit 32 determines that the in-focus areas E1 to E3 are not in focus and switches to pan focus (Step S14). C16). Pan focus is also called “ordinary focus” or “fixed focus” and does not focus on a specific part of the subject, but fixes the focus at a place of 2 to 3 m, for example, to increase the depth of field. This means that the entire range from the close range to the telephoto range is in focus.

(Second method)
In the first method, all evaluation values are used as determination elements. However, in the second method, evaluation values that are less than a predetermined value are excluded from the target, and the remaining evaluation values, that is, evaluations that are equal to or higher than the predetermined value are excluded. The focus position is determined from the value.

  FIG. 6 is a flowchart showing the focus determination process executed in step B22 and the focus determination process by the second method.

  First, the control unit 32 selects only the evaluation values of the focus target areas E1 to E3 corresponding to the position P0 in the evaluation table 57 that are equal to or greater than a predetermined value (step D11), and uses these evaluation values. The sum is obtained by addition (step D12). For example, when the predetermined value = 50, in the example of FIG. 11, the evaluation value 50 of E3 out of the focus target areas E1 to E3 corresponding to the position P0 is excluded, and the evaluation values of E1 and E2 Only the total value is obtained. The same applies to the other positions P1 to P6, and the total value is obtained only for evaluation values equal to or greater than a predetermined value.

  The subsequent processing is the same as in FIG. That is, when the total value of the evaluation values is obtained for all the positions P0 to P6 (Yes in Step D13), the control unit 32 detects the one having the highest total value (Step D14). If the detected total value is equal to or greater than the predetermined value (Yes in step D15), the control unit 32 determines that each focusing target area E1 to E3 is in focus, and the lens position (total value). Is determined as the in-focus position (step D16).

  On the other hand, if the detected total value is less than the predetermined value (No in Step D15), the control unit 32 determines that the in-focus areas E1 to E3 are not in focus and switches to pan focus (Step S15). D17).

  In this way, evaluation values that are less than the predetermined value are excluded from the beginning, and the focusing position is determined from the remaining evaluation values, that is, evaluation values that are equal to or higher than the predetermined value, thereby improving the focusing accuracy and more appropriately. The in-focus position can be obtained.

(Focus display processing)
Next, the focus display process executed in step A15 will be described. The in-focus display process refers to a process for displaying an image and color of a focused part on the through image screen.

  FIG. 7 is a flowchart showing the flow of the focus display process.

  When the focus is adjusted for the plurality of focus target areas E1 to E3 designated by the user by the automatic focusing process described above, the focus frames 51 to 53 displayed in the focus target areas E1 to E3 are displayed. It is indicated that the focus has been changed by changing the form (step E11). Changing the display form of the focus frames 51 to 53 is, for example, changing the display color or shape. Note that when the focus target areas E1 to E3 cannot be focused and the pan focus is achieved, the focus display process here is not performed.

  Here, for example, when the user issues an in-focus image display instruction by operating the menu key 16 (Yes in Step E12), the control unit 32 starts from the currently displayed through image 50 to each image in the focus frames 51 to 53. Is extracted as an image of a portion in focus (referred to as a focused image) (step E13). And the control part 32 opens the window screens 54a-54c as shown in FIG. 9 in the predetermined position on a screen, and each displays the said focused images 55a-55c there (step E14). In this example, since “flower”, “person's face”, and “signboard” are in focus from the left toward the subject, images of these portions are displayed as focused images 55a to 55c. It will be.

  The window screens 54a to 54c may be opened one by one in order according to a predetermined operation, or all may be opened at once.

  Moreover, as a display method of the focused images 55a to 55c, the entire focused images 55a to 55c may be displayed, or only a part including the center may be displayed. At that time, the image may be enlarged and displayed in a predetermined size.

  On the other hand, when the user gives a color display instruction, for example, by operating the menu key 16 (Yes in step E15), the control unit 32 starts from the currently displayed through image 50 to the center portion 1 of the image within the focus frames 51 to 53. The dot color data is extracted as the color of the in-focus portion (step E16). Then, the control unit 32 opens the window screens 54a to 54c as shown in FIG. 9 at predetermined positions on the screen, and displays the color marks 56a to 56c there based on the detected color data (step E17). . In this example, since “flower”, “person's face”, and “signboard” are in focus, the corresponding color marks 56a to 56c are displayed.

  The shapes and sizes of the color marks 56a to 56c are arbitrarily set, and can be arbitrarily selected by the user from various shapes such as a rectangle and a circle, and can be arbitrarily changed according to the mark size. .

  In the example of FIG. 9, the focused images 55a to 55c and the color marks 56a to 56c are displayed in the same window screens 54a to 54c. However, they may be displayed on separate window screens.

  Such in-focus images 55a to 55c and color marks 56a to 56c are, for example, explicitly instructed to cancel the display by operating the menu key 16, or until the focus lock is released by releasing the finger from the shutter key 9. Is displayed during

  As described above, according to the first embodiment, any plurality of portions on the screen can be designated as the in-focus target area, and anyone can easily obtain a still image in which these designated portions are in focus. be able to.

  In addition, it is possible to display an image and color of a portion focused by a predetermined operation. Thus, the user can take a picture while accurately grasping where the subject is in focus.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.

  In the first embodiment, the user designates an arbitrary plurality of portions on the screen as the focus target area. However, in the second embodiment, when the user designates an arbitrary color, It is characterized by focusing on the specified color part.

  Note that the external configuration and circuit configuration of the digital camera 1 are the same as those in the first embodiment, and therefore, differences in processing will be described here.

  FIG. 12 is a flowchart showing a processing operation at the time of photographing by the digital camera 1 in the second embodiment of the present invention.

  When the still image shooting mode is set by operating the shooting mode key 10 provided in the digital camera 1 after the power is turned on, the image of the subject is captured through the lens optical system 22 and the CCD 23, and after undergoing a predetermined color process. The through image is displayed on the screen of the display unit 19 (step F11).

  Here, for example, when the color designation mode is instructed by operating the menu key 16 (Yes in Step F12), the control unit 32 (CPU 32a) displays a color designation window 61 as shown in FIG. 14 (Step F12).

  The color designation window 61 is provided with a number of color samples 62a, 62b, 62c. The user selects a sample corresponding to the color to be focused from among these color samples 62a, 62b, 62c. As a method for selecting a color sample, for example, if a transparent touch panel is mounted on the screen of the display unit 19, the portion where the desired color sample is displayed on the screen with a finger or a pen is directly touched for selection. And a method of selecting by operating a cursor key.

  Further, the color designation window 61 is not limited to the configuration shown in FIG. 14, but may be configured to input R, G, and B numerical values constituting color data, for example.

  When the color to be focused is designated by the display of the color designation window 61 as described above, the control unit 32 stores the data of the designated color in a predetermined area of the RAM 32c (step F14), and then presents the current color. An image block having the color data is detected from the image data displayed as a through image (step F15).

  Specifically, for example, when RGB data is taken as an example of color data, dots whose numerical values of R, G, and B are within the specified color range (for example, R ± 10, G ± 10, B ± for the specified color). An image block including a predetermined number or more of dots within the range of 10 is detected.

  As shown in FIG. 15, the image block is one unit when the entire area of the image data is divided into, for example, 8 × 8 pixels. If this image block has a predetermined number or more of dots (pixels) within the range of the designated color, it is set as a focus target area. In the example in the figure, the hatched portion indicates the corresponding dot collection, and the image block surrounded by the thick line is detected as the focus target area.

  When an image block having the designated color data is detected in this way, the control unit 32 sets the detected image block as a focusing target area, and displays that effect on the corresponding part on the screen. Is performed (step F16). In this case, if there are a plurality of corresponding image blocks, these are set as the focusing target area, and a display to that effect is displayed. Specifically, as shown in FIG. 16, focus frames 71 to 71 are provided on a portion detected as a focus target area in the image data displayed as the through image 70, that is, a portion having a color designated by the user. 73 is displayed.

  With such display of the focus frames 71 to 73, the user can know the portion focused by color designation. In the example of FIG. 16, for example, by specifying “skin color”, focus frames 71 to 73 are respectively displayed on the “right hand”, “face”, and “left hand” of the person from the left side toward the subject. You can see that the focus is on the part of.

  By the way, in the method of automatically focusing on the color portion designated by the user, the portion intended by the user is not necessarily focused. For example, even if you specify "skin color" to focus on a person's face, if another person is nearby, the focus will be adjusted including that person's face. .

  Therefore, in order to avoid such a problem, after the focus target area is displayed in step F16, the control unit 32 executes a process for changing the focus target area in accordance with a user instruction (step F17). .

  FIG. 13 shows a flowchart of the focusing object changing process.

  That is, for example, when the user issues a deletion instruction by a predetermined operation such as touching a portion to be deleted from the focus target area on the screen (Yes in step G11), the control unit 32 corresponds to the specified portion. By searching for an image block, the image block is deleted from the focusing target area (step G12). Specifically, a process of deleting the image block from a management table (not shown) that manages the focus target area is performed. As a result, the focus frame displayed in the deleted image block also disappears.

  Further, for example, when the user gives an addition instruction by a predetermined operation such as touching a part to be added as a focus target area on the screen (Yes in step G13), the control unit 32 corresponds to the designated part. The image block is searched, and the image block is added to the focus target area (step G14). Specifically, processing such as adding the image block from a management table (not shown) that manages the focusing target area is performed. As a result, the focus frame is additionally displayed at the portion corresponding to the added image block.

  Subsequent processing is the same as in the first embodiment.

  That is, when the user gives a focus instruction by half-pressing the shutter key 9 (Yes in Step F18), the control unit 32 performs AF processing (automatic focus) on a plurality of focus target areas set by the color designation. Process) (step F19), and subsequently, an in-focus display process for displaying the image and color of the portion focused by the AF process is executed (step F20).

  Here, when the user gives a shooting instruction by depressing the shutter key 9 (Yes in Step F21), the control unit 32 executes a predetermined shooting process to capture the currently displayed through image as a still image. Then, it is compressed by a predetermined method and recorded in the memory 38 (step F22). The photographing process has been described in detail with reference to FIG.

  Further, the AF process executed in step F19 is the same as that shown in FIGS. That is, by detecting a high frequency component (contrast) obtained at each lens position while moving the focus lens 22a, an evaluation value corresponding to each focus target area is obtained, and the focus position is determined based on the evaluation value. Process.

  Further, the focus display process executed in step F20 is the same as that in FIG. That is, for example, when there is an in-focus image display instruction by operating the menu key 16, each of the images in the focus frames 71 to 73 from the currently displayed through image 70 is an in-focus image (in-focus). (Referred to as an image), and each of the extracted focused images is displayed in a window.

  Specifically, window screens 74a to 74c as shown in FIG. 17 are opened at predetermined positions on the screen, and the extracted focused images 75a to 75c are displayed there, respectively. In this example, by specifying “skin color”, the person's “right hand”, “face”, and “left hand” are in focus from the left side toward the subject, so the images of these portions are in-focus images. It will be displayed as 75a-75c.

  The window screens 74a to 74c may be opened one by one in order according to a predetermined operation, or all may be opened at once.

  Moreover, as a display method of the focused images 75a to 75c, the entire focused images 75a to 75c may be displayed, or only a part including the center may be displayed. At that time, the image may be enlarged and displayed in a predetermined size.

  On the other hand, for example, when there is a color display instruction by operating the menu key 16, a portion where the color data of one dot center of each image in the focus frames 71 to 73 is in focus from the currently displayed through image 70 is in focus. These colors are detected and displayed in a window.

  Specifically, window screens 74a to 74c as shown in FIG. 17 are opened at predetermined positions on the screen, and color marks 76a to 76c are displayed there based on the detected color data. In this example, since the “right hand”, “face”, and “left hand” of the person are in focus by designating “skin color”, “skin color” is displayed as the color marks 76a to 76c corresponding to each. Will be.

  The shapes and sizes of the color marks 76a to 76c are arbitrarily set, and can be arbitrarily selected by the user from various shapes such as a rectangle and a circle, and can be arbitrarily changed according to the mark size. .

  In the example of FIG. 17, the focused images 75a to 75c and the color marks 76a to 76c are displayed in the same window screens 74a to 74c. However, they may be displayed on separate window screens.

  Such in-focus images 75a to 75c and color marks 76a to 76c are explicitly instructed to cancel display by, for example, operating the menu key 16, or until the focus lock is released by releasing the finger from the shutter key 9. Is displayed during

  As described above, according to the second embodiment, by designating a color, it is possible to focus on the designated color. In this case, even if the part has the specified color, if the part is not intended by the user, it can be deleted or another part added to focus on the part desired by the user. Shooting can be performed.

  Further, by displaying the image and color of the portion that has been focused by a predetermined operation, the user can more accurately grasp where the subject is focused and perform shooting.

  In the above embodiment, the digital camera has been described as an example. However, the present invention is not limited to this, and a through image is displayed on a screen such as a digital movie camera capable of taking a still image or a mobile phone with a camera. However, the present invention can be applied to all electronic devices provided with a function capable of shooting a still image.

  In addition, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the respective embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  In addition, the methods described in each of the above-described embodiments are, as programs that can be executed by a computer, for example, a recording medium such as a magnetic disk (flexible disk, hard disk, etc.), an optical disk (CD-ROM, DVD, etc.), and a semiconductor memory. The program itself can be applied to various apparatuses, or the program itself can be transmitted through a transmission medium such as a network to be applied to various apparatuses. A computer that implements this apparatus reads a program recorded on a recording medium or a program provided via a transmission medium, and performs the above-described processing by controlling the operation by this program.

FIGS. 1A and 1B are diagrams illustrating an external configuration when a digital camera is taken as an example of an imaging apparatus according to a first embodiment of the present invention, in which FIG. 1A is mainly a front configuration, and FIG. FIG. FIG. 2 is a block diagram showing an electronic circuit configuration of the digital camera in the embodiment. 6 is a flowchart showing processing operations at the time of shooting by the digital camera in the embodiment. 6 is a flowchart showing the flow of the entire automatic focusing process of the digital camera in the embodiment. It is a flowchart which shows the focus determination process by the 1st method, which is the focus determination process of the digital camera in the embodiment. It is a flowchart which shows the focus determination process by the 2nd method which is a focus determination process of the digital camera in the embodiment. 6 is a flowchart showing a flow of focus display processing of the digital camera in the embodiment. It is a figure which shows an example of the through image display screen of the digital camera in the embodiment, and is a figure when a plurality of places are designated as the focus target area. The figure which shows an example of the window screen for displaying the image and color of the part which adjusted the focus of the digital camera in the embodiment. The figure for demonstrating the contrast detection system used for the digital camera in the embodiment. The figure which shows the structure of the evaluation table with which the digital camera in the embodiment is equipped. 9 is a flowchart showing processing operations at the time of photographing by a digital camera according to the second embodiment of the present invention. 6 is a flowchart showing focusing target change processing of the digital camera in the embodiment. FIG. 5 is a diagram showing an example of a color designation window displayed when color designation is performed on the digital camera according to the embodiment. FIG. 4 is a diagram for explaining a method for detecting a color-designated image block of the digital camera according to the embodiment. It is a figure which shows an example of the through image display screen of the digital camera in the embodiment, and is a view when focusing is performed by color designation. The figure which shows an example of the window screen for displaying the image and color of the part which adjusted the focus of the digital camera in the embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Digital camera, 2 ... Body, 3 ... Shooting lens, 4 ... Self-timer lamp, 5 ... Optical finder window, 6 ... Strobe light emission part, 7 ... Microphone part, 8 ... Power key, 9 ... Shutter key, 10 ... Photographing Mode key, 11 ... Playback mode key, 12 ... Optical viewfinder, 13 ... Speaker unit, 14 ... Macro key, 15 ... Strobe key, 16 ... Menu (MENU) key, 17 ... Ring key, 18 ... Set key, DESCRIPTION OF SYMBOLS 19 ... Display part, 21 ... Motor, 22 ... Lens optical system, 23 ... CCD, 24 ... Timing generator (TG), 25 ... Driver, 26 ... Sample hold circuit (S / H), 27 ... A / D converter 28 ... Color process circuit, 29 ... DMA controller, 30 ... DRAM interface (I / F), 31 ... DRAM, 32 ... Control unit, 33 ... VR M controller, 34 ... VRAM, 35 ... digital video encoder, 36 ... key input unit, 37 ... image processing unit, 38 ... memory, 39 ... audio processing unit, 40 ... USB interface (I / F), 42 ... movement detection unit 50 ... Through image, 51-53 ... Focus frame, 54a-54c ... Window screen, 55a-55c ... Focus image, 56a-56c ... Color mark, 57 ... Evaluation table, 61 ... Color designation window, 62a, 62b, 62c ... color sample, 71-73 ... focus frame, 74a-74c ... window screen, 75a-75c ... focused image, 76a-76c ... color mark.

Claims (12)

Imaging means for imaging a subject;
Display means for displaying the image data of the subject obtained by the photographing means as a through image;
Designating means for designating an arbitrary plurality of portions in the through image displayed by the display means as an in-focus target area;
Evaluation value calculating means for calculating a focus evaluation value based on image data corresponding to a plurality of focus target areas specified by the specifying means;
An imaging apparatus comprising: control means for focusing on each focus target area based on the focus evaluation value calculated by the evaluation value calculation means.   The imaging apparatus according to claim 1, wherein the control unit switches to pan focus when the focus target areas are not in focus. Color detection means for detecting the color of the in-focus portion from the through image;
The image pickup apparatus according to claim 1, further comprising color display means for displaying the color detected by the color detection means in a predetermined format. Image extracting means for extracting an image of a portion in focus from the through image;
The imaging apparatus according to claim 1, further comprising: an image display unit that displays the image extracted by the image extraction unit in a predetermined format. Imaging means for imaging a subject;
Display means for displaying the image data of the subject obtained by the photographing means as a through image;
A designation means for designating an arbitrary color;
A focus target setting means for detecting a portion having a color designated by the designation means in the through image displayed by the display means, and setting the corresponding portion as a focus target area;
An imaging apparatus comprising: control means for focusing on a focus target area set by the focus target setting means.   6. The focus target changing means for deleting the focus target area set by the focus target setting means or adding another part as the focus target area. Imaging device. Color detection means for detecting the color of the in-focus portion from the through image;
6. The imaging apparatus according to claim 5, further comprising color display means for displaying the color detected by the color detection means in a predetermined format. Image extracting means for extracting an image of a portion in focus from the through image;
6. The imaging apparatus according to claim 5, further comprising: an image display unit that displays an image extracted by the image extraction unit in a predetermined format. A focusing processing method used in an imaging device including an imaging device that images a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image,
Designating any plurality of portions in the through image displayed on the display unit as an in-focus target area;
Calculating a focus evaluation value based on image data corresponding to the plurality of designated focus target areas;
And a step of focusing on each focus target area based on the calculated focus evaluation value. A focusing processing method used in an imaging device including an imaging device that images a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image,
A step of specifying an arbitrary color;
Detecting a portion having the specified color in the through image displayed on the display unit, and setting the corresponding portion as a focusing target area;
And a step of focusing on the set focus target area. A program used for a computer that controls an imaging device including an imaging device that images a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image,
In the computer,
A function of designating an arbitrary plurality of portions in the through image displayed on the display unit as a focus target area;
A function for calculating a focus evaluation value based on image data corresponding to the plurality of designated focus target areas;
A program that realizes a function of focusing on each focus target area based on the calculated focus evaluation value. A program used for a computer that controls an imaging device including an imaging device that images a subject and a display unit that displays image data of the subject obtained by the imaging device as a through image,
In the computer,
The ability to specify any color,
A function of detecting a part having the designated color in the through image displayed on the display unit and setting the corresponding part as a focus target area;
A program characterized by realizing a function of focusing on the set focus target area.

Images