Digital camera

A digital camera comprising an imaging device, a memory, a monitor, and a monitor controller is provided. The digital camera is used for photographing an optical image of an object as an image of a first rectangle. An aspect ratio of the first rectangle is a first aspect ratio. The imaging device generates an image signal. The monitor is a second rectangle. An aspect ratio of the second rectangle is a second aspect ratio. The second aspect ratio is decided to be lower than the first aspect ratio if the first aspect ratio is higher than one. The second aspect ratio is decided to be higher than the first aspect ratio if the first aspect ratio is lower than one. The monitor controller makes a displayed-image be displayed on the monitor according to a first or a second replay mode.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a digital camera that can display a captured image while being rotated according to a position of the digital camera on photographing.

2. Description of the Related Art

In the prior art, the imaging device used for a digital camera is formed to a rectangle, having long and short sides. The imaging device is mounted in the digital camera so that the long sides can be parallel to the horizon when the digital camera is in the regular position. In addition, the digital camera has a rectangular monitor, whose aspect ratio is the same as that of the imaging device. The monitor is usually mounted in the digital camera so that the long sides of the monitor can be parallel to the horizon when the digital camera is in the regular position.

Accordingly, a wide-width-photograph, whose width is greater than the height, is taken when the digital camera is in the regular position. On the other hand, a tall-height-photograph, whose height is greater than the width, is taken when the digital camera is in a vertical position, where the digital camera is rotated around the optical axis by 90 degrees. When the tall-height-photograph is replayed on the monitor, a user should rotate the digital camera by 90 degrees.

As for the above problem, Japanese Patent Publication No. 2002-232753 discloses a digital camera to display the tall-height-photograph automatically rotated by 90 degrees. Then, the tall-height-photograph is displayed on the monitor with a scale-down.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to provide a digital camera that can display a tall-height-photograph on the monitor without a scale-down.

According to the present invention, a digital camera comprising an imaging device, a memory, a monitor, and a monitor controller is provided. The digital camera is used for photographing an optical image of an object as an image of a first rectangle. An aspect ratio of the first rectangle is a first aspect ratio. The first rectangle has first long sides and first short sides. The imaging device generates an image signal. The image signal corresponds to an optical image of the object. The memory stores the image signal generated by the imaging device. An image corresponding to the image signal is displayed on the monitor. The monitor is a second rectangle. An aspect ratio of the second rectangle is a second aspect ratio. The second aspect ratio is decided to be lower than the first aspect ratio if the first aspect ratio is higher than one. The second aspect ratio is decided to be higher than the first aspect ratio if the first aspect ratio is lower than one. The second rectangle has first sides and second sides. The monitor controller causes a displayed-image to be displayed on the monitor according to a first or a second replay mode. The displayed-image corresponds to the image signal stored in the memory. The displayed-image is displayed such that the first long side is parallel to the first side and an aspect ratio of the displayed-image is the same as the first aspect ratio in the first replay mode. The displayed-image is displayed as being rotated by 90 degrees in the second replay mode. The displayed-image is displayed such that the first long side is parallel to the second side and the aspect ratio of the displayed-image is the same as a reciprocal number of the first aspect ratio in the second replay mode.

Further, the displayed-image is displayed at maximum along the first side in the first replay mode. The displayed-image is displayed at maximum along the second side in the second replay mode.

Further, the second aspect ratio is substantially one.

Further, the digital camera comprises a switch. The switch causes the monitor controller to switch between the first replay mode and the second replay mode.

Further, the digital camera comprises a position sensor. The position sensor detects whether the digital camera is inclined with respect to a straight line perpendicular to a light receiving surface of the imaging device. The position detector generates inclination-signal when the position sensor detects that the digital camera is inclined. The memory stores the inclination-signal associated with the image signal. The inclination-signal is generated at the same time as when the image signal is generated. The monitor controller switches between the first replay mode and the second replay mode based on the inclination-signal.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is described below with reference to the embodiment shown in the drawings.

FIG. 1illustrates a front side appearance of a digital camera of an embodiment of the present invention.FIG. 2illustrates a back side appearance of a digital camera of an embodiment of the present invention.

A photographing lens11and a flash12are mounted on the front side of the digital camera10. The photographing lens11enables an optical image of an object to be in focus on the light receiving surface of the imaging device13mounted in the digital camera10. The flash is used to illuminate an object when the periphery of the object is dark.

A release button14and a power button15are mounted on the top face of the digital camera10, hereinafter referred to as TF. The power of the digital camera10is switched on and off by pushing on the power button15. An object is photographed by pushing on the release button14.

A bottom face of the digital camera10, hereinafter referred to as BF, and the TF are parallel. Both faces are formed so that both faces can be parallel to an optical axis of the photographing lens11. Incidentally, a position where the TF and BF are parallel to the horizon is defined as a regular position of the digital camera10. On the other hand, a position where the digital camera10is rotated around the optical axis of the photographing lens11by 90 degrees is defined as a vertical position.

A replay button16, a menu button17, a cross key18, a zoom button19, and a monitor20are mounted on the back face of the digital camera10. The replay button16, the menu button17, the cross key18, and the zoom button19are used for user's command input for some functions.

The monitor20is formed as a square. The monitor20is arranged so that two sides of the monitor20are parallel to the TF and BF. Incidentally, the sides parallel to the TF and BF is defined as a first side, hereinafter referred to as FS. The side perpendicular to the TF and BF is defined as a second side, hereinafter referred to as SS.

A photographing mode, a replay mode, and a setting mode are set up for the digital camera10. A user may change and select the mode.

When the digital camera10is powered on, the digital camera10is in the photographing mode. The change between the photographing mode and the replay mode is carried out by pushing the replay button16. The change between the photographing mode and the setting mode is carried out by pushing the menu button17.

In the photographing mode, a thru-image is displayed on the monitor20. Incidentally, the thru-image is the same as the optical image of an object captured by the imaging device13in real time. In the replay mode, the saved static image of an object by a photographing operation is displayed on the monitor20. In the setting mode, a setting-image for changing some settings of the digital camera10(for example, an exposure compensation) is displayed on the monitor20, and a user may change some settings.

The zoom button19is used to adjust a focal length of the photographing lens11in the photographing mode. The zoom button19is used to zoom in and to zoom out a replayed image in the replay mode. The cross key18is used to change some settings of the digital camera10.

Next, the internal structure of the digital camera10is explained with reference toFIG. 3. The digital camera10comprises the photographing lens11, the imaging device13, a digital signal processor, hereinafter referred to as a DSP21, a system controller22, the monitor20, a memory connector23, a position sensor24, and other components.

The photographing lens11is optically connected to the imaging device13. An optical image of an object through the photographing lens11is incident to the light receiving surface of the imaging device13. The photographing lens11and the imaging device13are arranged so that an optical axis of the photographing lens11can be perpendicular to the light receiving surface of the imaging device13. The imaging device13is a CMOS imaging device. When the imaging device13captures an optical image of the object, the imaging device13generates an image signal corresponding to the optical image.

As shown inFIG. 4, an image receiving area is formed in the center of the light receiving surface of the imaging device13. A black area is formed around the image receiving area at the light receiving surface. An optical image through the photographing lens11is received by the image receiving area, and then the image receiving area generates a signal corresponding to the optical image. The black area generates a signal corresponding to a standard black level of the received optical image. The signal corresponding to the optical image and the signal corresponding to the standard black level together form one frame of the image signal. The imaging device13outputs the image signal generated as described above.

Incidentally, the image receiving area is formed so that the aspect ratio of the image receiving area is 4:3. In addition, the imaging device13is arranged inside of the digital camera10so that the longer side of the image receiving area is parallel to the TF and the BF.

The imaging device13is connected to the DSP21through an A/D converter25(seeFIG. 3). An image signal generated by the imaging device13is converted into a digital signal from an analog signal by the A/D converter25. The image signal, having undergone the A/D conversion processing, is sent to the DSP21.

The DSP21carries out predetermined signal processing for the image signal sent to the DSP21. The image signal, having undergone the predetermined signal processing, is sent to the monitor20. An image, corresponding to the image signal sent to the monitor20, is displayed on the monitor20.

When a release operation is carried out, one frame of the image signal, having undergone the predetermined signal processing, is stored on a memory card28, which is connected to the DSP21via a memory connector23. Incidentally, the memory card28may be connected to and disconnected from the memory connector23as necessary.

The DSP21is connected to the system controller22. The system controller22commands the DSP21to carry out the predetermined signal processing. In addition, the system controller22controls the entire operation of the digital camera10.

The system controller22is connected to the position sensor24. The position sensor24detects whether the digital camera10is kept substantially in a vertical position. The position sensor24outputs a vertical-position signal to the system controller22when the digital camera10is kept substantially in a vertical position. The vertical-position signal is used by the system controller22when storing the image signal on the memory card28, and when displaying an image corresponding to the image signal stored on the memory card28, as described later.

The system controller22is connected to the input unit26, which comprises the replay button16, the menu button17, the cross key18, the zoom button19, the release button14, and the power button15. When a user inputs a command to the input unit26, a command signal corresponding to the command given is sent to the system controller22. The system controller22controls the components of the digital camera10according to the command signal.

For example, when the replay button16is pushed on, the system controller22commands the DSP21so that the thru-image and a static image to display on the monitor20are switched. When the menu button17is pushed on, the system controller22commands the DSP21so that the thru-image and the setting-image to display on the monitor20are switched.

Also, when the zoom button19is pushed on in the photographing mode, the system controller22commands a lens driving unit (not depicted) so that the focal length of the photographing lens11can be adjusted.

In addition, when the release button14is fully pushed on in the photographing mode, the system controller22commands a timing generator27to drive the imaging device13so that the imaging device13captures an optical image and generates an image signal. Further, if the vertical-position signal is sent to the system controller22when the release button14is fully pushed, the vertical-position signal is added to the image signal as rotate-information and stored on the memory card28.

Further, when the zoom button19is pushed on in the replay mode, the system controller22commands the DSP21so that the static image is displayed on the monitor20enlarged, and the magnification of the enlargement is adjusted.

Also, when the cross key18is pushed in the replay mode, the system controller22commands the DSP21so that the displayed static image is changed.

Next, an image, displayed on the monitor20in the photographing mode, is described in detail below with reference toFIG. 5andFIG. 6.

The thru-image is displayed on a portion of the monitor20designed for displaying the thru-image, hereinafter referred to as the image-displaying portion. The image-displaying portion is near the TF of the monitor20in the photographing mode. In addition, photographing information is displayed on a separate portion of the monitor20, hereinafter referred to as the information-displaying portion. In addition, the information-displaying portion is near the BF of the monitor20in the photographing mode. Incidentally, the photographing information is information regarding some settings of the digital camera10and the current status of the photographing mode.

The information regarding some settings of the digital camera10may contain, for example, the focus, the shutter speed, the aperture value, the on/off status of the flash, the picture quality, the white balance, the photometry area, and the ISO sensitivity. The information regarding the current status may contain, for example, the current time, the remaining power of the battery, and a histogram of the thru-image.

The photographing information is displayed symbolically using predetermined icons, characters, and/or graphs. There are top and bottom sides for the photographing information. When the digital camera10is kept in any position except for a vertical position, the photographing information is displayed so that the top and bottom sides of the photographing information are toward the TF and BF, respectively (seeFIG. 5).

On the other hand, when the digital camera10is kept in a vertical position, the photographing information is displayed so that the top and bottom sides of the photographing information are toward the left and right faces of the digital camera10, hereinafter referred to as LF and RF, respectively (seeFIG. 6).

Consequently, the top and bottom sides of the photographing information and the arrangement of the individual items comprising the photographing information are different when the digital camera10is held in the vertical position and when the digital camera10is held in any other position arrived at by rotating the digital camera10between 0-180 degrees from the vertical position. On the other hand, the locations of the image-displaying portion and the information-displaying portion are the same in the photographing mode.

It is determined that the digital camera10is in the regular position when the vertical-position signal is not added to the image signal. On the other hand, it is determined that the digital camera10is in a vertical position when the vertical-position signal is added to the image signal.

Next, an image, displayed on the monitor20in the replay mode, is described in detail below with reference toFIG. 7andFIG. 8.

The replay mode comprises a first and a second replay mode. Either the first or the second replay mode is automatically selected according to an image signal corresponding to a displayed image in the replay mode. The system controller22selects the first replay mode when the vertical-position signal is not added to the image signal. On the other hand, the system controller22selects the second replay mode when the vertical-position signal is added to the image signal.

In the first replay mode, the static image is displayed on the monitor20so that the longer side of the static image is parallel to the FS. In addition, the magnification is adjusted so that the longer side of the static image occupies proportionally the same length of the FS as the captured optical image. Incidentally, the photographing information is displayed on a portion of the monitor20separate from the portion of the monitor20for displaying the static image on the monitor20. Accordingly, the static image is displayed on the same portion of the monitor20in the first replay mode as the image-displaying portion in the photographing mode, and the photographing information is displayed on the same portion of the monitor in the first replay mode as the information-displaying portion in the photographing mode.

In the second replay mode, the static image is displayed on the monitor20so that the longer side of the static image is parallel to the SS. In addition, the magnification is adjusted so that the longer side of the static image occupies proportionally the same length of the SS as the captured optical image. In addition, the static image is displayed on a portion of the monitor20near the LF of the monitor20. Incidentally, the photographing information is displayed on a portion of the monitor20separate from the portion of the monitor20for displaying the static image on the monitor20. Accordingly, the portion of the monitor20displaying the photographic information is near the RF of the monitor20.

Incidentally, the top and bottom sides of the photographing information are toward the TF and BF, respectively.

Next, some operations in the photographing or replay mode carried out by the system controller22and the DSP21are explained below, using the flowcharts ofFIG. 9andFIG. 10.

The photographing mode starts when the power of the digital camera10is switched on, the replay button16is pushed on in the replay mode, or the menu button17is pushed on in the setting mode. At step S100, the DSP21receives an image signal generated by the imaging device13. Then the predetermined signal processing is carried out for the received image signal.

At step S101, it is determined whether the position sensor24outputs the vertical-position signal. If the vertical-position signal is output, the process goes to step S102. At step S102, the thru-image and the photographing information are displayed on the monitor20. Incidentally, the direction and the location of the displayed photographing information are adjusted so that the direction from the top side to the bottom side of the photographing information is parallel to the FS (seeFIG. 6).

If the vertical-position signal is not output at step S101, the process goes to step S103. Also at step S103, the thru-image and the photographing information are displayed on the monitor20. Incidentally, the direction and the location of the displayed photographing information are adjusted so that the direction from the top side to the bottom side of the photographing information is parallel to the SS (seeFIG. 5).

After step S102or step S103, the process goes to step S104. At step S104, it is determined whether the release switch14is switched on. If the release switch14is not switched on, the process returns to step S100, and step S100˜step S104are repeated until the release switch14is switched on.

If the release switch14is switched on, the process goes to step S105. At step S105, the image signal, having undergone the predetermined signal processing, is stored on the memory card28.

After storing the image signal on the memory card28, the process goes to step S106. At step S106, it is determined whether the position sensor24outputs the vertical-position signal. If the vertical-position signal is output, the process goes to step S107. At step S107, the vertical-position signal is added to the image signal, and the image signal is stored on the memory card28.

If the vertical-position signal is not output at step S106, or after finishing the processing of step S107, the process goes to step S108. At step S108, it is determined whether there is a command to finish photographing, such as a command by pushing the replay button16, or by pushing the menu button17. If such a command is not input, the process returns to step S100, and step S100˜step S108are repeated until such a command is input. If such a command is input at step S108, the operations in the photographing mode are finished.

The replay mode starts when the replay button16is pushed on in the photographing mode, as described above. In the replay mode, a user may select an image to display on the monitor20. At step S200, the DSP21receives an image signal, corresponding to the selected image to display, from the memory card28. After receiving, the process goes to step S201. At step S201, it is determined whether a vertical-position signal was added to the received image signal.

If, at step S201, the vertical-position signal was not added to the received image signal, the process goes to step S202. At step S202, the first replay mode is selected, and then the static image of wide width is displayed on the monitor20while the digital camera10is kept in the regular position.

If, at step S201, the vertical-position signal was added to the received image signal, the process goes to step S203. At step S203, the second replay mode is selected, and then the static image of tall height is displayed on the monitor20while the digital camera10is kept in the regular position.

After displaying the static image of wide width or of tall height, the operations to display a static image are finished.

In the above embodiment, it is possible to display a rotated static image of tall height that is photographed in a vertical position of the digital camera10even if the magnification of the enlargement of the displayed static image is the same as that of the static image of wide width. The reason is described as follows. The first side of the monitor20is as long as the second side of the monitor20. The static image of wide width is displayed so that the longer side of the static image is as long as the first side of the monitor20and the static image of tall height is displayed so that the longer side of the static image is as long as the second side of the monitor20.

In addition, a user can easily check the photographing information in the photographing mode, especially in the vertical position of the digital camera10. The reason is that the direction of the displayed photographing information changes according to whether the digital camera10is kept in a vertical position.

In addition, a user can easily observe a thru-image or a static image, and the photographing information, together. In the prior art, the photographing information is superimposed on a thru-image or a static image. However, in the above embodiment, the photographing information is displayed on a portion of the monitor20separate from the portion of the monitor20for displaying a thru-image or a static image of the monitor20. Consequently, the thru-image or the static image and the photographing information are observed respectively easily, as described above.

The monitor20is formed as a square in the above embodiment. However, the monitor20may be formed as a rectangle as long as the aspect ratio of the monitor20is lower than the aspect ratio of the image receiving area of the imaging device13, which is 4/3, for displaying the static image of tall height as tall as possible. Further, it is preferable that the aspect ratio of the monitor20be higher than a reciprocal number of the aspect ratio of the image receiving area in order to prevent the displayed static image of wide width from being too small. Further, it is more preferable that the aspect ratio of the monitor20be near one.

In the above embodiment, the width of the image receiving area of the imaging device13is greater than the height in the regular position of the digital camera10, and the aspect ratio of the image receiving area is higher than one. However, the height of the image receiving area may be greater than the width, as long as the aspect ratio of the monitor20is higher than the aspect ratio of the image receiving area for displaying the static image of wide width as wide as possible. Further, it is preferable in this case that the aspect ratio of the monitor20be lower than the reciprocal number of the aspect ratio of the image receiving area in order to prevent the displayed static image of tall height from being too small.

A static image is displayed in the replay mode so that a longer side of the static image is as long as either the FS or the SS of the monitor20in the above embodiment. However, the length of the longer side may be different from either the FS or the SS. Of course, an entire static image may be displayed as large as possible within the portion of the monitor for the image both in the first and in the second replay mode, such as in the above embodiment. However, even if the entire static image cannot be displayed as large as possible either in the first or in the second replay mode, the entire static image, both in the first and in the second replay mode, can still be larger than in the prior art.

A position sensor24is used in the above embodiment. However, another device or another system, which informs the system controller22of whether the digital camera10is kept in a vertical position in the photographing or the replay mode, may alternatively be used. For example, a position change switch may be used. The position change switch may be used for the user's command input when the user changes the position of the digital camera10in the photographing mode. Alternatively, the position change switch may be used for a user to select the first or the second replay mode directly.

The position sensor24is used for determining whether the digital camera10is kept in a vertical position in the above embodiment. However, a tilt sensor that detects an angle of inclination to the ground may alternatively be used. Such a sensor may detect the angle of rotation of the digital camera10around an imaginary axis perpendicular to the light receiving surface relative to the regular position. In addition, a situation in which the angle of inclination from the regular position is over 45 degrees may be regarded as a vertical position if the tilt sensor is used. Accordingly, the direction of the photographing information may be rotated, or a vertical-position signal may be added to the image signal, when the angle of inclination is over 45 degrees.

The photographing information is displayed on a portion of the monitor20separate from the portion of the monitor20for displaying a static image on the monitor20in the above embodiment. However, the photographing information may, alternatively be superimposed on the static image. The rotated static image may then be displayed without lowering the magnification, even while the photographing information is superimposed. Of course, the photographing information should be displayed on a portion of the monitor20separate from the portion of the monitor20for displaying the static image on the monitor20, for a user's easy viewing. Incidentally, in any embodiment, when the static image is zoomed in by adjusting the magnification, the photographing information may be superimposed on the static image. In addition, when the magnification is over a predetermined cited value, the photographing information may disappear.

The aspect ratio of a static image is the same as that of the image receiving area of the imaging device13in the above embodiment. However, the aspect ratio of the static image may be decided according to signal processing carrying out at the DSP21. For example, a static image, whose aspect ratio is different from that of the image receiving area, may be generated by trimming, at the DSP21, a image captured by the image receiving area. The aspect ratio of the monitor20should be between the aspect ratio of the trimmed static image and the reciprocal number of the aspect ratio of the trimmed static image if the aspect ratio of the static image is decided according to the signal processing.

A static image is displayed on the monitor20in the above embodiment. However, the static image may alternatively be displayed on another monitor of a display that is connected to the memory card28storing the image signal having the vertical-position signal. In addition, the static image may be displayed on another monitor of a display that is connected to the digital camera10.

Although the embodiments of the present invention have been described herein with reference to the accompanying drawings, obviously many modifications and changes may be made by those skilled in this art without departing from the scope of the invention.

The present disclosure relates to subject matter contained in Japanese Patent Application No. 2006-014039 (filed on Jan. 23, 2006), which is expressly incorporated herein, by reference, in its entirety.