JP2000078445A - Digital camera - Google Patents

Abstract

(57) [Abstract] [Problem] To check framing simultaneously with focusing. When an image of a subject is captured by a digital camera, an entire display area of a display section is set by an enlarged area setting section.
The position of the marker 75 for specifying the image area 74 to be enlarged is set and input to the image processing unit 15. The image processing unit 15 displays the marker 75 at the input position of the display unit 7 and specifies an image area to be enlarged. When the focusing operation is started, the image processing unit 15 reads out the entire image data stored in the frame memory 16 and reads out the entire display area 7 of the display unit 7.
1, the image data of the enlarged image area 74 specified by the marker 75 is read out, enlarged at a predetermined magnification, and displayed in the enlarged display area 72 of the display unit 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a digital camera, and more particularly to an accurate focusing at the time of imaging.

[0002]

2. Description of the Related Art In a digital camera, an image is taken while monitoring an image on a liquid crystal display. In a digital camera, the number of pixels of the liquid crystal display is smaller than the number of pixels of an imaging device such as a CCD and the size of the liquid crystal display itself is small. It has been difficult to confirm the correct focus during imaging. On the other hand, in the imaging apparatus disclosed in JP-A-6-70206 and JP-A-9-116792, a part of a captured image is enlarged by optical zoom and displayed on the entire liquid crystal display to check the focus. Is made easy.

[0003]

However, if a part of the captured image is enlarged and displayed on the entire liquid crystal display during confirmation of focus, framing cannot be confirmed during confirmation of focus. It is necessary to display the entire captured image on the liquid crystal display after confirmation of the above, and the operation becomes complicated.

An object of the present invention is to provide a digital camera which can solve such disadvantages and can simultaneously confirm focus and framing.

[0005]

A digital camera according to the present invention is characterized in that an entire image to be captured and an image obtained by enlarging a part of the captured image are simultaneously displayed on a display unit.

A second digital camera according to the present invention comprises:
An image obtained by enlarging an entire image to be captured, a part of the captured image, and imaging information at that time are simultaneously displayed on a display unit.

A third digital camera according to the present invention comprises:
The whole image to be captured is displayed on the display unit, and an image obtained by enlarging a part of the image to be captured according to the distance to the subject is displayed on the display unit.

It is desirable that the size and position of a part of the image to be captured can be set arbitrarily. Also, the size and position of a part of the set image to be captured can be changed according to the distance to the subject, and the size and position of the part of the set image to be captured can be determined by either the magnification of the zoom lens or the angle of view of the lens. It may be variable depending on one or both information.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A display section of a digital camera according to the present invention has an entire display area for displaying an entire image to be captured, an enlarged display area for enlarging and displaying a part of the image to be captured, and an imaging mode and other imaging modes. It has an imaging information display area for displaying information. The entire display area for displaying the entire image captured by the display unit has a marker for specifying an image area to be enlarged. The display unit is connected to an image processing unit that performs image processing, and sets a position of a marker that specifies an image region to be enlarged from the enlargement region setting unit in the image processing unit.

When an image of a subject is taken by the digital camera, first, a position of a marker for specifying an image area to be enlarged of the entire display area of the display section is set by an enlargement area setting section and input to the image processing section. The image processing unit displays a marker at the input position on the display unit and specifies an image area to be enlarged.
In this state, a focusing operation is started, image data is input to the image processing unit, and the image data is temporarily stored in the frame memory. 1
When the image portion is stored in the frame memory, the image processing unit reads out the entire image data stored in the frame memory, displays the entire image data on the entire display area of the display unit, and continuously outputs the image data of the enlarged image area specified by the marker. The image area to be read and enlarged is enlarged at a predetermined magnification, for example, a magnification corresponding to the size of the enlarged image area specified by the marker and the size of the enlarged display area of the display section, and displayed in the enlarged display area of the display section.
In this state, the image formed is focused. When focusing an image formed in this way,
By displaying the formed whole image and the image in the image area used for focusing, it is possible to focus while checking the framing by looking at the whole formed image.

[0011]

FIG. 1 is an external view showing an embodiment of the present invention. As shown in FIG. 1A, a surface on the imaging side of the digital camera 1 has a lens 2, an optical finder 3 and a strobe 4, and a shutter button 5 on an upper surface. As shown in FIG. 1B, the back surface of the digital camera 1 has a plurality of setting buttons 6 for setting an imaging mode and the like and a display unit 7 composed of a liquid crystal display.
Storage unit. The display unit 7 includes an entire display area 71 for displaying the entire image to be captured, an enlarged display area 72 for enlarging and displaying a part of the image to be captured, and an imaging mode, the number of images that can be captured, and a strobe mode. It has an imaging information display area 73 for displaying imaging information. The entire display area 71 for displaying the entire image captured by the display unit 7 has a marker 75 for specifying the image area 74 to be enlarged, as shown in the display diagram of FIG.

As shown in the block diagram of FIG. 3, the digital camera 1 includes a plurality of lenses 11, an aperture 12 for adjusting the amount of light incident from the lens 11, a CCD 13 for converting the incident light into an electric signal, A CDS / CDS that removes a noise component included in an output signal of the CCD 13, amplifies the signal component, and converts the amplified analog signal into a digital signal.
A / D converter 14, pixel interpolation, gain correction for each color, γ
Image processing unit 1 that performs image processing such as correction and aperture correction
5, a frame memory 16 for temporarily storing image data to be processed by the image processing unit 15, a DCT / coder 17 for compressing and expanding image data, and an SRA for storing image data.
A memory 18 such as an M or a flash memory, a D / A converter 19 for converting image data, which is a digital signal, into an analog signal and outputting it as a video signal to the outside, and moving each lens of the lens 1 with a motor, a solenoid or the like. Lens drive unit 20 for changing the focus position of an image formed on CCD 3 by means of a diaphragm, aperture drive unit 21 for changing the aperture of aperture 12 with a solenoid or the like, and drive pulses for CCD 13 and CDS / A / D converter 14 Generator 2 that generates
2, an automatic exposure control unit 23 that controls the amount of incident light on the CCD 3 from the output of the image processing unit 15, an automatic focus detection unit 24 that detects the focus position of an image to be captured from the output of the image processing unit 15, and an image processing unit. 15, a white balance control unit 25 for controlling the white balance of the image captured from the output, a CPU 26 for controlling the operation of the entire apparatus, and a display unit 7 for capturing an image.
Has an enlarged area setting section 27 for setting the position of the marker 75 provided in the entire display area 71 of the image forming apparatus. Enlarged area setting unit 2
7 is a setting button 6, a touch panel, a joystick,
It consists of a joypad and the like.

The operation of the digital still camera configured as described above when recording an image will be described.

When the power button of the digital camera 1 is turned on to set the image recording mode, and then the shutter button is half-pressed, the amount of light of the image incident on the lens 11 is adjusted by the aperture 12 to form an image on the CCD 13. The image formed on the CCD 13 is converted into an electric signal according to the amount of light for each pixel, and is sequentially sent to the CDS / A / D conversion unit 14 at regular intervals. The CDS / A / D converter 14 removes and amplifies the noise component of the transmitted signal, converts it to digital signal image data, and sends it to the image processor 15. The image data sent to the image processing unit 15 is once stored in the frame memory 16.
The frame memory 16 has a capacity capable of storing the image of the CCD 13 for two screens or more, and outputs the previously stored image data to the image processing unit 15 in the same manner as storing the image data sent from the image processing unit 15. . This frame memory 1
The area for storing the image data and the area for outputting the image data are switched for each screen of the image sent from the image processing unit 15. 1 which is changed and output from the frame memory 16
The image data before the screen is red R, green G,
Blue B or Yellow Ye, Cyan Cy, Magenta M
g, green G, etc., having color data of color filters formed on the light receiving elements of the CCD 13. Image processing unit 15
Performs pixel interpolation of the transmitted image data, and if the color filter of the CCD 13 is other than R, G, B, performs conversion to R, G, B, so that each pixel has a signal of each color of R, G, B. To Then, image processing such as gain correction, γ correction, and aperture correction is performed for each color, and further converted into a luminance signal and a color difference signal, and the converted image data is sent to the display unit 7 to display a monitor image. The monitor image displayed on the display unit 7 is updated at regular intervals. The image processing unit 15 is provided with a white balance control unit 25 separately from the output to the display unit 7.
And outputs a signal of each color of R, G, B for each pixel, and creates and outputs a luminance signal from the signal of each color of R, G, B to the automatic exposure control unit 23 and the automatic focus detection unit 24.

When the image data obtained by converting the R, G, and B signals of each pixel into a luminance signal from the image processing unit 15 is input from the image processing unit 15, the automatic exposure control unit 23 sets a predetermined range in the input image data. , The exposure amount of the CCD 13 is calculated, and the calculated exposure amount calculation value is sent to the CPU 26. C
The PU 26 controls the CCD 13 based on the sent exposure calculation value.
CDS / A / D conversion unit 14 so that the exposure amount of
, The aperture drive 12 is operated to adjust the aperture 12, and the electronic shutter speed of the CCD 13 is changed via the timing generator 22. When the automatic focus detection unit 24 receives image data obtained by converting the R, G, and B signals of each pixel into a luminance signal from the image processing unit 15,
The amount of high frequency components included in the image data is calculated for a preset range in the input image data. This operation is performed for a plurality of positions while moving the lens 11 by the lens driving unit 20 and changing the focus position of the image formed on the CCD 13 from infinity to the close distance or from the close distance to infinity. Then, the position where the calculation result becomes maximum is output to the CPU 26 as the focus position of the image formed on the CCD 13. CPU2
Reference numeral 6 denotes a lens driving unit 2 so as to be at an input focus position.
0 is operated to move and position the lens 11. When the image data of each color of R, G, B for each pixel is input from the image processing unit 15, the white balance control unit 25 receives the input from the distribution of each color of R, G, B for a preset range in the input image data. The color deviation of the image is calculated and output to the CPU 26. The CPU 26 changes the gain of the color correction of the image processing unit 15 for each color so as to eliminate the color bias from the sent color bias calculation result.

After the image pickup conditions are determined by the automatic exposure control unit 23, the automatic focus detection unit 24, and the white balance control unit 25, the photographer is notified by turning on an LED or the like. In this state, the photographer further presses the shutter button to capture an image. The image data processed by the image processing unit 15 is compressed by the DCT / coder 17 and stored in the memory 18.
Is stored in When displaying the image data stored in the memory 18 on the display unit 7, the data compressed by the DCT / coder 17 is expanded, and the image processing unit 15 prints the characters, numerals, pictograms, Are displayed on the display unit 7. Further, the image data stored in the memory 18 is converted into analog data by a D / A converter 19 and output to the outside as a video output.

The digital camera 1 configured as described above
The operation for focusing an image formed on the CCD 13 when imaging an object with the camera will be described with reference to the flowchart of FIG.

When the focusing is started, first, as shown in FIG. 3, a position of a marker 75 for specifying an image area 74 to be enlarged in the entire display area 71 of the display section 7 is set in the enlarged area setting section 27. The image processing unit 15 which inputs the image data to the image processing unit 15 displays a marker 75 at the input position of the display unit 7 and specifies the image area 74 to be enlarged (step S).
1). When the focusing operation is started in this state, CP
U26 operates the lens drive unit 20 to move the lens 11 to the focus detection operation start position, and from the CCD 13 to the CDS
Image data is input to the image processing unit 15 through the A / D conversion unit 14, and is temporarily stored in the frame memory 16 (steps S2 and S3). When one image is stored in the frame memory 16, the image processing unit 15 switches the area for storing the image data in the frame memory 16 and reads out the image data already stored in the frame memory 16 line by line to the display unit 7 line by line. It performs pixel interpolation, image processing, conversion into a luminance signal and a color difference signal, displays the result on the display unit 7, and performs a focus detection operation. In the reading method, first, one line of the entire display area 71 is read and displayed in the entire display area (step S4), and then it is determined whether the reading of the enlarged area specified by the marker 75 has been completed. (Step S5) If the reading is not completed,
One line of the image area to be enlarged specified by the marker 75 is read out, displayed on the enlarged display area 72 following the end of one line of the entire display area 71, and sent to the focus detection unit 24 at the same time (step S6). The focus detection unit 24 performs an operation for focus detection (step S7). On the other hand, when the reading has been completed, one row of the background signal is stored in the imaging information display area 73 following the end of one row of the entire display area 71 so that the enlarged area has a constant color and brightness. Output (Step S8). Then, it is determined whether the reading of the entire display area 71 has been completed (step S9), and this operation is repeated until the reading of the entire display area 71 is completed (steps S4 to S9).

When reading the entire display area of the image data stored in the frame memory 16 and the image area 74 to be enlarged, the image processing section 15 sets the horizontal m pixels × the vertical n pixels of the frame memory 16 as shown in FIG. A block of pixels (m and n are integers equal to or greater than 2) is sequentially read out at a fixed pattern interval in the horizontal direction from the read target pixel at the top of the row. In the enlarged image area 74 specified by the marker 75, blocks of m horizontal pixels × n vertical pixels (m and n are integers of 2 or more) are sequentially read from the head pixel. When moving to the next line, the whole display area 71 moves to a line vertically spaced from the previous line at a fixed interval, and moves to an adjacent line without a space in the enlarged area 74 designated by the marker 75. When the reading of the entire display area 71 is completed, the focus detection unit 24 ends the calculation of the focus detection at the current focus position and stores the result inside (step S10). The CPU 26 performs this operation by moving the lens 11 by the lens
3 is performed for a plurality of positions while changing the focus position of the image formed on 3 from infinity to a close distance or from the close distance to infinity (steps S11, S3 to S3).
S10). After the calculation of the focus detection at all positions is completed (step S11), the focus position is determined from the calculation result of the focus detection for each focus position stored in the focus detection unit 24 and output to the CPU 26 (step S12). CPU2
Reference numeral 6 denotes a lens drive unit which moves the lens 11 to a position where the focus is detected by the focus detection unit 24 (step S13).

When the image formed on the CCD 13 is focused as described above, the entire image formed on the CCD 13 and the image of the image area 74 used for focusing are displayed, respectively. Accurate focusing can be performed while checking framing by looking at the entire image to be formed.

In the above embodiment, focusing is performed automatically. However, when focusing is performed manually, an image is displayed in both the entire display area 71 and the enlarged display area 72 of the display unit 7 as in the above embodiment. By displaying, it is possible to perform accurate focusing while checking the framing while viewing the entire image to be formed.

In the above embodiment, the case where the enlarged image area 74 of the entire display area 71 of the display unit 7 is surrounded by the marker 75 and specified is described. However, as shown in the display diagram of FIG. The display of the image area 74 to be enlarged and the display of the other areas may be displayed with a luminance difference. By providing the luminance difference in this way, it is possible to easily set the image area 74 to be enlarged.

When displaying the image area 74 which is enlarged with respect to the enlarged display area 72 of the display section 7, it is preferable to display the imaging information at that time in the imaging information display area 73. By displaying the imaging information together with the enlarged image area 74, the imaging information at that time can be confirmed while focusing.

Although the above embodiment has been described with respect to the case where images are displayed in the entire display area 71 and the enlarged display area 72 of the display unit 7 when focusing, the CPU 26 responds to the output of the lens drive unit 20 in accordance with the output. It is also possible to switch between displaying the image only in the whole display area 71 or displaying the image in both the whole display area 71 and the enlarged display area 72. For example, as shown in FIG.
Only in the macro area where the imaging distance becomes short and the depth of field becomes shallow, the image is displayed in both the entire display area 71 and the enlarged display area 72. In this way, by switching between displaying the image only in the entire display area 71 or displaying the image in both the entire display area 71 and the enlarged display area 72 according to the distance to the subject, accurate framing can be performed while confirming framing. Focusing can be facilitated.

In the above embodiment, the position of the marker 75 for specifying the image area 74 to be enlarged is set by the enlarged area setting section 27. The position may be changed by the CPU 26 according to the position of each lens output from the lens driving unit 20 when focusing. For example, FIG.
As shown in (a), the subject shows a large area in the image when the distance to the subject is short, but as shown in (b) and (c), as the distance to the subject increases, the image becomes larger. Area becomes smaller. Therefore, as the distance to the subject increases, the enlarged image area 74 specified by the marker 75 is reduced, and the magnification of the image displayed in the enlarged display area 72 is increased. By thus increasing the enlargement ratio of the image displayed in the enlarged display area 72, it is possible to achieve more accurate focusing.

Further, as shown in FIG. 9, when a zoom control unit 28 is provided and a zoom lens is used as the lens 11, any one of the position and angle of view of each lens output from the zoom control unit 28 is used. It is preferable to change the size and position of the marker 75 set by the enlarged area setting unit 27 by one or both. Thus, by changing the size and position of the marker 75 according to the position and angle of view of each lens, it is possible to accurately perform focusing while checking framing even when the magnification is changed. Further, as shown in FIG. 10, whether or not to display in the enlarged area setting unit 27 may be selected according to the angle of view of the lens and the distance to the subject.

[0027]

As described above, according to the present invention, when focusing an image to be formed, the entire image formed and the image in the image area used for focusing are displayed. It is possible to focus while checking the framing by looking at the entire image to be formed.

Further, by displaying the imaging information at that time together with the formed whole image and the image of the image area used for focusing, it is possible to accurately confirm the imaging information at that time while focusing. it can.

Further, by displaying an enlarged image of a part of the image to be captured according to the distance to the subject,
Accurate focusing can be performed while checking framing.

Further, since the size and position of a part of the image to be enlarged and displayed can be arbitrarily set, accurate focusing can be performed more easily.

The size and position of a part of the set image to be picked up can be changed according to the distance to the subject, or the set size and position of the part of the image to be picked up can be changed by the magnification of the zoom lens and the angle of view of the lens. By varying the information in accordance with one or both of the information, accurate focusing can be reliably performed.

[Brief description of the drawings]

FIG. 1 is an external view of an embodiment of the present invention.

FIG. 2 is a display diagram of a display unit of the embodiment.

FIG. 3 is a block diagram showing a configuration of the embodiment.

FIG. 4 is a flowchart showing the operation of the embodiment.

FIG. 5 is an explanatory diagram showing an operation of reading image data from a frame memory.

FIG. 6 is a display diagram showing another display example of the display unit.

FIG. 7 is an explanatory diagram illustrating a display state according to a distance to a subject.

FIG. 8 is a display diagram showing changes in the size and position of a marker depending on the distance to a subject.

FIG. 9 is a block diagram illustrating a configuration of a digital camera using a zoom lens.

FIG. 10 is an explanatory diagram showing a display state based on a field angle of a lens and a distance to a subject.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Digital camera 7 Display part 71 Entire display area 72 Enlarged display area 73 Imaging information display area 74 Image area to be enlarged 75 Marker 11 Lens 12 Aperture 13 CCD 15 Image processing part 16 Frame memory 20 Lens drive part 24 Automatic focus detection part 26 CPU 27 Enlarged area setting section

Claims (6)

[Claims] 1. A digital camera wherein an entire image to be captured and an image obtained by enlarging a part of the captured image are simultaneously displayed on a display unit. 2. A digital camera, wherein an entire image to be captured, an image obtained by enlarging a part of the captured image, and imaging information at that time are simultaneously displayed on a display unit. 3. A digital camera, wherein an entire image to be captured is displayed on a display unit, and an image obtained by enlarging a part of the image to be captured according to a distance to a subject is displayed on the display unit. 4. The digital camera according to claim 1, wherein the size and position of a part of the captured image can be arbitrarily set. 5. The digital camera according to claim 4, wherein a size and a position of a part of the set image to be picked up are changed according to a distance to a subject. 6. The digital camera according to claim 4, wherein the size and the position of a part of the set image to be picked up are changed according to one or both of the magnification of the zoom lens and the angle of view of the lens. .