Imaging apparatus, method for controlling imaging apparatus, and program

Abstract

To enable reduction of power consumption in a photographing standby state, and enable display of a recorded image during photographing.SOLUTION: An imaging apparatus has: imaging means; a first integrated circuit that generates image data to be displayed on a display on the basis of image data acquired from the imaging means; a second integrated circuit that records the image data acquired from the imaging means through the first integrated circuit in a recording medium, and generates image data to be displayed on the display and corresponding to the image data to be recorded; power supply control means that controls power supply; switching means that outputs the image data to the display; and control means that, in a photographing standby state, performs control to restrict power supply to the second integrated circuit and output the image data generated by the first integrated circuit to the display. The control means performs control to cancel the restriction of the power supply to the second integrated circuit according to an instruction to record moving images in the photographing standby state, and output the image data generated by the second integrated circuit to the display.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an imaging device, a control method for an imaging device, and a program. [Background technology]

[0002] Conventionally, an imaging device has been proposed that processes image data acquired by an imaging circuit using two LSIs, one for the front engine and one for the back engine (Patent Document 1). In a shooting standby state, the imaging device normally displays an image captured by the imaging sensor as a live view image. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-197608 Summary of the Invention [Problem to be solved by the invention]

[0004] The imaging device disclosed in Patent Document 1 needs to operate both the front engine and the rear engine while displaying a live view image. Therefore, power is required to drive both engines even while displaying a live view image. The present invention aims to reduce power consumption in a shooting standby state and to enable the display of recorded images during shooting. [Means for solving the problem]

[0005] The imaging device of the present invention comprises an imaging means, a first integrated circuit that acquires image data from the imaging means and generates image data to be displayed on a display unit based on the image data acquired from the imaging means, a second integrated circuit that acquires image data from the imaging means via the first integrated circuit, records the image data acquired via the first integrated circuit on a recording medium, and generates image data to be displayed on the display unit corresponding to the image data recorded on the recording medium based on the image data acquired from the first integrated circuit, a power supply control means that controls the supply of power to the second integrated circuit, a switching means that outputs image data generated by the first integrated circuit or image data generated by the second integrated circuit to the display unit, and a control means that, in a shooting standby state, causes the power supply control means to limit the supply of power to the second integrated circuit and controls the switching means to output the image data generated by the first integrated circuit to the display unit, wherein the control means, in response to an instruction to record a moving image in the shooting standby state, releases the power supply control means' restriction on the supply of power to the second integrated circuit and controls the switching means to switch the image data to be output to the display unit from the image data generated by the first integrated circuit to the image data generated by the second integrated circuit. [Effects of the Invention]

[0006] According to the present invention, it is possible to reduce power consumption in a shooting standby state, and to display a recorded image during shooting. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 illustrates an example of the configuration of a digital camera. [Figure 2A] 10 is a flowchart illustrating the operation of the digital camera. [Figure 2B] 10 is a flowchart illustrating the operation of the digital camera. [Figure 3] 10 is a flowchart illustrating an operation of the digital camera in a playback mode. [Figure 4] 10 is a flowchart illustrating an operation of the digital camera when outputting to an external device. [Figure 5] 10 is a flowchart illustrating an operation of the digital camera in a playback mode during external output. [Figure 6A] 10 is a flowchart illustrating the operation of the digital camera when simultaneously outputting to external devices. [Figure 6B] 10 is a flowchart illustrating the operation of the digital camera when simultaneously outputting to external devices. [Figure 7] 10 is a flowchart illustrating the operation of the digital camera in a power saving mode. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] First Embodiment Fig. 1 is a block diagram showing an example of the configuration of a digital camera 100 as an example of an imaging device according to this embodiment. In Fig. 1, a lens unit 140 is detachably attached to the digital camera 100 and has a photographing lens 141. The photographing lens 141 is usually composed of multiple lenses, but for simplicity's sake, it is shown here as only one lens. A barrier 142 covers the imaging system including the photographing lens 141 of the digital camera 100, thereby preventing the imaging system including the photographing lens 141, shutter 101, and imaging unit 102 from getting dirty or damaged.

[0010] The shutter 101 is a shutter with an aperture function. The imaging unit 102 has an imaging element that converts an optical image into an electrical signal, and an A / D converter that converts an analog signal output from the imaging element into a digital signal and outputs image data. The imaging element is, for example, a CCD image sensor or a CMOS image sensor. The imaging unit 102 may have an imaging surface phase difference sensor that outputs defocus amount information to the system control unit 122. The imaging unit 102 is capable of outputting video data at 120 frames per second, with one frame having 4K pixels (3840 pixels horizontally × 2160 pixels vertically), for example.

[0011] The front engine 120 is configured as one semiconductor integrated circuit chip (IC chip). The front engine 120 has one or more processors or circuits. The front engine 120 has an image processing unit 121 that processes image data acquired from the imaging unit 102, a system control unit 122 that controls the entire digital camera 100, and a display device control unit 125. The front engine 120 is an example of a first integrated circuit.

[0012] The front engine 120 processes the image data acquired from the imaging unit 102 in the image processing unit 121, and displays a live view image on the display unit 113. Here, live view (live view function) is a function that enables the user to check the target (subject) to be photographed, the angle of view, the shooting conditions, etc., on the image displayed on the display unit 113. The live view image is an image displayed on the display unit 113 in the live view function. When the live view function is enabled, the imaging unit 102 continuously acquires image data for multiple frames, and outputs moving image data consisting of these multiple frames as image data for the live view image.

[0013] The image processing unit 121 performs predetermined pixel interpolation, resizing such as reduction, and color conversion processing on image data acquired from the imaging unit 102. The image processing unit 121 also performs predetermined arithmetic processing using the acquired image data, and the system control unit 122 performs exposure control, distance measurement control, and the like based on the obtained arithmetic results. This allows TTL (through-the-lens) AF (autofocus) processing, AE (autoexposure) processing, and EF (flash pre-flash) processing to be performed. The image processing unit 121 may also perform predetermined arithmetic processing using the acquired image data, and TTL AWB (auto white balance) processing based on the obtained arithmetic results. The data that has undergone image processing by the image processing unit 121 is written to, for example, a memory 127.

[0014] The memory 127 is a memory for the front engine 120 that is used for various processes in the front engine 120. For example, the memory 127 is used to store image data before and after processing when the image processing unit 121 processes the image data. The memory 127 is, for example, a dynamic random access memory (DRAM) or a magnetoresistive random access memory (MRAM). It is also possible to store a portion of the image data before and after processing in a portion of the system memory 126.

[0015] The image data that has been image-processed by the image processing unit 121 can be output to the display unit 113 using the display control unit 124, the display device control unit 125, and the display signal switching unit 112. The display control unit 124 controls the startup and shutdown of the display unit 113 and issues image data output control instructions to the display device control unit 125. The display device control unit 125 has a circuit for outputting a display signal to the display unit 113, and can use this circuit to display a live view image on the display unit 113 via the display signal switching unit 112. Display signal communication between the display device control unit 125, the display signal switching unit 112, and the display unit 113 is performed using a high-speed serial I / F such as MIPI (Mobile Industry Processor Interface), for example.

[0016] The display signal switching unit 112 is connected to the display device control unit 125 of the front engine 120 and the display device control unit 135 of the main engine 130. The display signal switching unit 112 switches the output path (transmission path) of the display signal so that either the display signal generated by the front engine 120 or the display signal generated by the main engine 130 is output to the display unit 113. The display unit 113 includes an electronic viewfinder, and the image processing unit 121 generates display image data according to the type of the display unit 113. The display unit 113 may be, for example, a liquid crystal panel or an organic EL panel.

[0017] The system control unit 122 controls the entire digital camera 100. The system control unit 122 has a processor or CPU. The processor or CPU of the system control unit 122 controls the imaging device 100 by executing programs stored in a system memory 126. The system memory 126 is a non-volatile storage medium that stores programs and parameters used by the system control unit 122 to control the overall operation of the digital camera 100. The system memory 126 stores, for example, programs for executing processes realized by various flowcharts described later in this embodiment. The system memory 126 may be, for example, a flash memory.

[0018] Furthermore, the front engine 120 controls the startup of the main engine 130 in accordance with the operation mode of the digital camera 100. The front engine 120 is a semiconductor integrated circuit that is different from at least the main engine 130, which will be described later.

[0019] The main engine 130 is configured as a single semiconductor integrated circuit chip (IC chip) separate from the front engine 120. The main engine 130 has one or more processors or circuits. The main engine 130 has an image processing unit 131 that processes image data acquired by the front engine 120 from the imaging unit 102, a system control unit 132 that controls each functional unit of the main engine 130, and a display device control unit 135. The main engine 130 is an example of a second integrated circuit.

[0020] The main engine 130 receives image data acquired by the front engine 120 from the imaging unit 102 and processes the data in the image processing unit 131. Here, the image processing performed by the image processing unit 131 has higher development processing performance than the image processing performed by the image processing unit 121. Therefore, the image processing unit 131 generates image data with a higher resolution and frame rate than the image data generated by the image processing unit 121. Furthermore, the power consumption of the image processing unit 131 is greater than the power consumption of the image processing unit 121 of the front engine 120.

[0021] The system control unit 132 of the main engine 130 has a processor and a CPU. The processor and CPU of the system control unit 132 execute programs stored in the system memory 136 to control the functions of each unit of the main engine 130 and realize these functions. The system control unit 132 has a recording and playback control unit 133 that stores image data processed by the image processing unit 131 on the recording medium 114. The recording and playback control unit 133 can also read image data from the recording medium 114 and output it to the image processing unit 131.

[0022] Image data processed by the image processing unit 131 can be output to the display unit 113 via the display control unit 134, the display device control unit 135, and the display signal switching unit 112. Like the image processing unit 121, the image processing unit 131 generates display image data according to the type of the display unit 113. Display signal communication between the display device control unit 135, the display signal switching unit 112, and the display unit 113 is performed using a high-speed serial I / F such as MIPI. Furthermore, when an external output function is enabled in the digital camera 100, the image data processed by the image processing unit 131 is output from the display device control unit 135 to the external device 115. The external device 115 includes, for example, a device that complies with the HDMI (registered trademark) standard. The external device 115 can be connected to the digital camera via a connection unit (not shown).

[0023] The system memory 136 is a non-volatile storage medium that stores programs and parameters used by the system control unit 132 of the main engine 130 to control each functional unit of the main engine 130. The system memory 136 may be, for example, a flash memory.

[0024] The memory 137 is a memory for the main engine 130 that is used for various processes in the main engine 130. For example, the memory 137 is a storage medium that stores image data before and after processing when the image processing unit 131 processes the image data. The memory 137 is, for example, a DRAM, an MRAM, or the like.

[0025] The power supply control unit 110 is composed of a battery detection circuit, a DC-DC converter, a switch circuit for switching between blocks that supply power, and the like. The power supply control unit 110 detects the state of the power switch 109, whether the power supply 111 is attached, the type of power supply 111, and the remaining power (remaining battery power) of the power supply 111. The power supply control unit 110 also controls the DC-DC converter based on the detection results and instructions from the system control unit 122 to supply necessary power for the necessary period to each unit, including the front engine 120 and the main engine 130. The power supply control unit 110 also supplies power to the recording medium 114 and the lens unit 140 under the control of the system control unit 122. When the digital camera 100 is in a shooting standby state, the power supply control unit 110 limits the power supplied to the main engine 130. Here, the shooting standby state refers to a state in which a live view image is displayed on the display unit 113 based on image data acquired by the imaging unit 102, and image data is not recorded on the recording medium 114, and image data stored on the recording medium 114 is not played back.

[0026] The power supply 111 is used as the power source for the digital camera 100. The power supply 111 is composed of a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, or a Li-ion battery, an AC adapter, or the like. The power supply 111 is detachable from the digital camera 100. The recording medium 114 is a recording medium such as a memory card for recording captured images, and is composed of a semiconductor memory, a magnetic disk, or the like.

[0027] The shutter button 107 is an operating member for issuing an instruction to capture a still image. The shutter button 107 has a first shutter switch and a second shutter switch. The first shutter switch is turned on (ON) when the shutter button 107 provided on the digital camera 100 is pressed halfway (a shooting preparation instruction) and generates a first shutter switch (SW1) signal. In response to receiving the first shutter switch (SW1) signal, the system control unit 122 executes shooting preparation operations such as AF (autofocus) processing, AE (auto exposure) processing, AWB (auto white balance) processing, and EF (pre-flash) processing. In other words, the first shutter switch (SW1) signal is a shooting preparation instruction. The first shutter switch is turned on (ON) when the shutter button 107 is pressed fully (a shooting instruction) and generates a second shutter switch (SW2) signal. In response to the second shutter switch (SW2) signal, the system control unit 122 starts a series of still image capturing and recording processing operations, from reading out a signal from the imaging unit 102 to writing the captured image to the recording medium 114 as an image file.

[0028] The moving image recording button 108 is an operating member for issuing an instruction to capture a moving image. When the moving image recording button 108 is pressed, the system control unit 122 starts a series of shooting and recording operations related to shooting a moving image, from reading out a signal from the imaging unit 102 to writing the captured image to the recording medium 114 as an image file. When the moving image recording button 108 is pressed again during the moving image shooting and recording operations, the system control unit 122 stops the moving image shooting and recording operations. The power button 109 is a button that the user uses to instruct the digital camera 100 to power on and off.

[0029] The operation unit 103 is one or more operation members for inputting various operation instructions to the system control unit 122. The operation unit 103 includes a mode changeover switch 104, a menu button 105, a play button 106, and the like.

[0030] The mode selector switch 104 switches the operating mode of the system control unit 122 between a still image capture mode, a video capture mode, etc. Modes included in the still image capture mode include an auto capture mode, an auto scene determination mode, a manual mode, an aperture priority mode (Av mode), a shutter speed priority mode (Tv mode), and a program AE mode (P mode). There are also various scene modes and custom modes that provide capture settings for specific capture scenes. The mode selector switch 104 allows the user to directly switch to one of these modes. Alternatively, the user may first switch to a list screen of capture modes using the mode selector switch 104, then select one of the displayed modes and switch using other operating members. Similarly, the video capture mode may also include multiple modes. The capture modes include a state in which a live view process is executed, which displays a live view image for capture preparation, such as checking the state and angle of view of the subject to be captured, and a state in which a capture / record process is executed, which captures an image of the subject and records the resulting image data on the recording medium 114.

[0031] The menu button 105 is an operation button for displaying a menu screen. When the menu button 105 is pressed, a menu screen that allows various settings to be made is displayed on the display unit 113, and the user can intuitively make various settings using the menu screen and operation members such as a cross key included in the operation unit 103. The image displayed on the display unit 113 is a single image in which multiple layers are superimposed, but the on-screen display layer on which the menu screen is drawn is located above the layer of display image data generated by image processing. The on-screen display image of the menu screen is generated by the system control unit 122 of the front engine 120. The user can also use the menu screen to set the screen size (number of pixels) and frame rate of the video data to be recorded. For example, if the user sets 4K and 60 fps, video data with 4K pixels per frame is shot and recorded at 60 frames per second.

[0032] The playback button 106 is an operation button for switching between a shooting mode and a playback mode, and pressing the playback button 106 during shooting mode switches to playback mode. In playback mode, images recorded on a recording medium 114 can be displayed on a display unit 113.

[0033] The operation of digital camera 100, including the control of front engine 120 and main engine 130 in each operating state, will be described below. When the user operates power button 109 to turn on the power of digital camera 100, system control unit 122 sets digital camera 100 to a shooting standby state. Then, in the shooting standby state, a live view image is displayed on display unit 113.

[0034] (When live view is displayed while waiting to shoot) In a standby state for shooting, the digital camera 100 uses the front engine 120 to display a live view image on the display unit 113. In a standby state for shooting, the main engine 130 is not used to display the live view image. Therefore, the supply of power to the main engine 130 is limited or stopped. In addition, the display signal switching unit 112 is set to output image data input from the front engine 120 by a startup process of the digital camera 100 or the like to the display unit 113. Hereinafter, the image data for display output to the display unit 113 will also be referred to as a display signal.

[0035] In a standby state, the system control unit 122 controls the imaging unit 102 to capture video data with a predetermined number of pixels and frame rate. Here, the system control unit 122 controls the imaging unit 102 to capture video data with 2K (1920 horizontal pixels × 1080 horizontal pixels) per frame at 30 fps. Furthermore, by reducing the number of pixels and frame rate of the video captured in a standby state compared to the number of pixels and frame rate of the video recorded during video recording, it is possible to reduce power consumption in a standby state. The front engine 120 processes image data acquired from the imaging unit 102 in the image processing unit 121. The image data processed by the image processing unit 121 is output to the display unit 113 using the display control unit 124, display device control unit 125, and display signal switching unit 112, and a live view image based on the image data from the front engine 120 is displayed.

[0036] (When shooting and recording video) The following describes video shooting and recording. When the user operates the video recording button 108 in a shooting standby state and issues an instruction to start video shooting, the video shooting and recording process begins. Based on the instruction to start video shooting, the system control unit 122 of the front engine 120 starts a series of video shooting and recording process operations related to video shooting, from reading signals from the imaging unit 102 to writing captured images to the recording medium 114 as image files. In response to the instruction to start video recording, the system control unit 122 controls the imaging unit 102 to shoot video with the number of pixels and frame rate set by the user. In response to receiving the instruction to start video shooting, the system control unit 122 also lifts restrictions on power supply to the main engine 130 or controls the power supply control unit 110 to start power supply, thereby starting the main engine 130. When video shooting begins, the system control unit 122 receives image data for each frame from the imaging unit 102 and outputs it to the main engine 130. The main engine 130 receives image data output from the front engine 120, processes the data in the image processing unit 131, and records the processed image data on the recording medium 114. When video shooting begins, the system control unit 122 outputs the image data from the imaging unit 102 to the main engine 130 without performing the above-mentioned processing for display.

[0037] Furthermore, the image data processed by the image processing unit 131 is output to the display unit 113 using the display control unit 134, the display device control unit 135, and the display signal switching unit 112, and a live view image based on the image data from the main engine 130 is displayed. This makes it possible to check on the display unit 113 high-quality (high resolution, high frame rate) image data generated by the image processing unit 131 and corresponding to the image data to be recorded on the recording medium 114. When shooting and recording a moving image, a switching instruction is issued from the display device control unit 125 of the front engine 120 to the display signal switching unit 112 to switch the engine (display signal output engine) that outputs image data to the display unit 113. Here, a switching instruction is output to the display signal switching unit 112 to switch the display signal output engine from the front engine 120 to the main engine 130. In response to this display signal output engine switching instruction, the display signal switching unit 112 switches the display signal output path so that the display signal input from the main engine 130 is output to the display unit 113.

[0038] In this way, after video shooting and recording has started, if the user operates the video recording button 108 again to issue an instruction to end video shooting, the video shooting and recording process is stopped. When the instruction to end video shooting is received, the system control unit 122 controls the power supply control unit 110 to limit the power supplied to the main engine 130 or to stop the power supply, thereby stopping the main engine 130. Furthermore, as described above, the system control unit 122 controls the imaging unit 102 to shoot video with a predetermined number of pixels and frame rate, and starts processing image data for live view images by the image processing unit 121. At the same time, the system control unit 122 controls the display device control unit 125 to output a switching instruction to the display signal switching unit 112 to switch the display signal output engine from the main engine 130 to the front engine 120. In response to this display signal output engine switching instruction, the display signal switching unit 112 switches the display signal output path so that the display signal input from the front engine 120 is output to the display unit 113. In this way, the video shooting and recording process ends, and the camera returns to the shooting standby state.

[0039] (When taking and recording still images) The following describes the operation when capturing and recording still images. When the shutter button 107 for capturing and recording still images is operated and half-pressed during standby for capturing images, a first shutter switch (SW1) signal (a capture preparation instruction) is input to the system control unit 122 of the front engine 120. In response to receiving the first shutter switch (SW1) signal, the system control unit 122 either lifts the restriction on the power supply to the main engine 130 or controls the power supply control unit 110 to start the supply of power, thereby starting the main engine 130.

[0040] Thereafter, when the shutter button 107 is operated and fully pressed, a second shutter switch (SW2) signal (still image capture instruction) is input to the system control unit 122 of the front engine 120. In response to receiving the second shutter switch (SW2) signal, the system control unit 122 starts a series of shooting and recording process operations related to still image capture, from reading out a signal from the imaging unit 102 to writing the captured image as an image file to the recording medium 114. When the SW2 signal is input, the system control unit 122 receives one frame of image data from the imaging unit 102 in response to the instruction of the SW2 signal, and outputs it to the main engine 130. The main engine 130 receives the image data from the front engine 120, processes it in an image processing unit 131, and records the processed image data on the recording medium 114.

[0041] Furthermore, in the shooting and recording process of still images, image data processed by image processing unit 131 is output to display unit 113 using display control unit 134, display device control unit 135, and display signal switching unit 112, and an image based on the image data is displayed as a preview image. System control unit 122 controls display device control unit 125 to output a display signal output engine switching instruction to display signal switching unit 112 so as to switch from image data from front engine 120 to image data from main engine 130. In response to this display signal output engine switching instruction, the display signal output path in display signal switching unit 112 is switched so that the display signal input from main engine 130 is output to display unit 113.

[0042] After displaying the preview image for a predetermined time, the digital camera 100 stops displaying the preview image and transitions to a shooting standby state. After displaying the preview image for a predetermined time, the system control unit 122 starts processing image data for a live view image by the image processing unit 121. At the same time, the system control unit 122 controls the display device control unit 125 to output an instruction to the display signal switching unit 112 to switch from image data from the main engine 130 to image data from the front engine 120. In response to this instruction to switch the display signal output engine, the display signal switching unit 112 switches the display signal output path so that the display signal input from the front engine 120 is output to the display unit 113. The system control unit 122 also controls the power supply control unit 110 to limit or stop the power supply to the main engine 130, thereby stopping the operation of the main engine 130. In this way, the still image shooting and recording process ends, and the digital camera transitions to a shooting standby state.

[0043] (When playing back images from a recording medium) The following describes image playback from a recording medium. When the user operates the playback button 106 while the digital camera 100 is in a standby state and receives an image playback instruction, the digital camera 100 starts playback processing of an image recorded on the recording medium 114. Upon receiving the image playback instruction, the system control unit 122 either lifts the restriction on power supply to the main engine 130 or controls the power supply control unit 110 to start supplying power, thereby starting the main engine 130. The recording and playback control unit 133 reads image data from the recording medium 114 and outputs it to the image processing unit 131, which then processes the image. The image data processed by the image processing unit 131 is output to the display unit 113 using the display control unit 134, display device control unit 135, and display signal switching unit 112, and an image based on the image data is displayed. When playing back a recorded image, the system control unit 122 controls the display device control unit 125 and outputs an instruction to the display signal switching unit 112 to switch from image data from the front engine 120 to image data from the main engine 130. In response to this display signal output engine switching instruction, the display signal output path in display signal switching unit 112 is switched so that the display signal input from main engine 130 is output to display unit 113. When a still image is played back, image data of the still image played back from recording medium 114 is output to and displayed on display unit 113. When a moving image is played back, image data of the moving image played back from recording medium 114 is output to and displayed on display unit 113. Then, when the user gives an instruction to stop playing the moving image, playing of the moving image is stopped, and the image data of the screen that was displayed at the time of the instruction to stop playing is repeatedly displayed on display unit 113.

[0044] As described above, when the user issues an instruction to switch from playback mode to shooting mode by operating SW1 or the like while playback of still images or videos is stopped, the system control unit 122 performs the following operation. The system control unit 122 controls the power supply control unit 110 to limit or stop the supply of power to the main engine 130, thereby stopping the main engine 130. The system control unit 122 also controls the display device control unit 125 to output an instruction to the display signal switching unit 112 to switch from image data from the main engine 130 to image data from the front engine 120. In response to this instruction to switch the display signal output engine, the display signal switching unit 112 switches the display signal output path so that the display signal input from the front engine 120 is output to the display unit 113. In this way, playback processing of the recorded image ends, and the system transitions to a shooting standby state.

[0045] 2A and 2B are flowcharts illustrating the overall operation of the digital camera 100 according to this embodiment. When the power switch 109 is turned from OFF to ON, the digital camera 100 starts the processing of the flowcharts shown in FIGS. 2A and 2B.

[0046] In S201, startup processing for the front engine 120 is executed. The power supply control unit 110 supplies power to the front engine 120 in response to receiving a startup instruction from the power supply switch 109 after the power supply switch 109 has been turned on. The system control unit 122 reads out a startup program and parameters from the system memory 126 and executes the startup operation. Meanwhile, the power supply control unit 110 does not supply the power necessary for the main engine 130 to operate in a normal state (it limits the supply of power to the main engine 130 or stops the supply of power).

[0047] In S202, a startup process is executed for the display system (functional units related to image display) related to the front engine 120. The system control unit 122 powers on the display unit 113, reads out setting data stored in the memory 127, and performs initialization to set various parameters for the display control unit 124 and the display device control unit 125. The system control unit 122 also sets the display signal switching unit 112 to output a display signal input from the front engine 120 to the display unit 113.

[0048] In S203, the system control unit 122 determines whether the external output function of the digital camera 100 is enabled. The system control unit 122 reads setting data stored in the system memory 126 and determines whether the external output function is enabled. Here, the external output function is a function that outputs an image to the external device 115 via a communication unit (not shown). The setting related to the external output function is set in advance by operating a menu screen. The menu screen is displayed on the display unit 113, and the user operates the operation unit 103 to set it to either enabled or disabled. If the system control unit 122 determines that the external output function is enabled (YES in S203), the process proceeds to S401 in FIG. 4. If the system control unit 122 determines that the external output function is disabled (NO in S203), the process proceeds to S204.

[0049] In S204, the system control unit 122 determines whether the operation mode of the digital camera 100 is the shooting mode. The system control unit 122, for example, reads out setting data stored in the system memory 126 to confirm the operation mode of the digital camera 100. Alternatively, for example, the system control unit 122 may confirm the operation mode of the digital camera 100 based on the operation mode indicated by the mode selector switch 104. If the system control unit 122 determines that the operation mode is the shooting mode (YES in S204), the process proceeds to S205. If the system control unit 122 determines that the operation mode is not the shooting mode (NO in S204), the process proceeds to S301 in FIG. 3. In this embodiment, if the operation mode is not the shooting mode, it is described as being the playback mode, but other modes may also be set.

[0050] In S205, the system control unit 122 executes live view processing. The live view processing is processing of image data acquired from the imaging unit 102 to generate a live view image and displays it on the display unit 113. When the live view processing is executed, an image (live view image) based on the image data acquired from the imaging unit 102 is displayed on the display unit 113. Note that the live view processing by the front engine 120 is executed at a low frame rate or low resolution, regardless of the camera settings related to shooting and recording that are set based on user operations or the like and stored in the memory 127. For example, even if the camera settings related to shooting and recording are set to an image recording frame rate of 60 fps and a recording size of 4K images, the system control unit 122 executes the live view processing in S205 by reading image data from the imaging unit 102 at 30 fps and with the pixel count of an FHD (2K) image. Therefore, a live view image can be generated and displayed with less power consumption than when the live view processing in S209, which will be described later, is executed. The system control unit 122 uses the display control unit 124, the display device control unit 125, and the display signal switching unit 112 to display on the display unit 113 a live view image generated by processing image data acquired from the imaging unit 102 in the image processing unit 121. The user can check the live view image displayed on the display unit 113 and determine the shooting conditions, etc., of the image to be shot (recorded). After the live view process is executed, the digital camera 100 stands by for shooting without performing the image capture and recording process until an instruction to shoot a still image is input by pressing the shutter button 107, etc., or an instruction to shoot a video is input by pressing the video recording button 108, etc.

[0051] In S206, the system control unit 122 determines whether a video shooting operation has been performed. That is, the system control unit 122 determines whether the user has pressed the video recording button 108 and issued a video shooting instruction by pressing the video recording button 108. If the system control unit 122 determines that a video shooting operation has been performed (YES in S206), the process proceeds to S207. If the system control unit 122 determines that a video shooting operation has not been performed (NO in S206), the process proceeds to S214.

[0052] In S207, a startup process is executed for the main engine 130. The system control unit 122 controls the power supply control unit 110 to instruct it to start supplying power to the main engine 130. That is, the power supply control unit 110 either removes the restriction on the power supplied to the main engine 130 or starts supplying power. The system control unit 122 also controls the system control unit 132 to execute a startup operation for the main engine 130.

[0053] In S208, a startup process for the display system (functional units related to image display) for the main engine 130 is executed. The system control unit 132 reads out setting data stored in the memory 137 and performs initialization to set various parameters for the display control unit 134 and the display device control unit 135. Here, by initializing the display control unit 134 and the display device control unit 135, the display signal for the image output from the main engine 130 is output from the display device control unit 135 to the display signal switching unit 112. However, at this point, the internal selector of the display signal switching unit 112 is set to output the display signal input from the display device control unit 125 to the display unit 113. Therefore, the display signal from the display device control unit 135 is not output to the display unit 113.

[0054] In S209, the system control unit 132 executes live view processing. In the live view processing in the main engine 130, RAW images acquired from the imaging unit 102 are transferred to the memory 137 via the memory 127 and processed by the image processing unit 131. The live view processing in S209 is performed at a frame rate or resolution according to the camera settings for shooting and recording that are set based on user operations or the like and stored in the memory 127. For example, if the camera settings for shooting and recording specify an image recording frame rate of 60 fps and a recording size of 4K images, as described above, image data is read from the imaging unit 102 at 60 fps and with the pixel count of a 4K image, and processing is performed. Therefore, unlike the case where the live view processing in S205 described above is performed, it is possible to generate a live view image that is the same as the image to be captured and recorded. Unlike the live view image generated in S205 for the purpose of power saving, the image generated in the live view processing in S209 can be processed at a high resolution and therefore may be enlarged.

[0055] In S210, the system control unit 122 determines whether or not the display destination ME switching process in S211, which will be described later, has not been performed. That is, the system control unit 122 determines whether or not the display destination ME switching process in S211 has already been performed. The display destination ME switching process is a process in which the display signal switching unit 112 switches the display signal input from the main engine 130 so that it is output to the display unit 113. If the system control unit 122 determines that the display destination ME switching process in S211 has not been performed (YES in S210), the process proceeds to S211. If the system control unit 122 determines that the display destination ME switching process has already been performed (NO in S210), the process proceeds to S212. In this way, the display destination ME switching process is performed only once when the ME startup process is performed.

[0056] In S211, a display destination ME switching process is executed. The system control unit 122 controls the display signal switching unit 112 to switch the internal selector of the display signal switching unit 112 so as to switch the display signal to be displayed on the display unit 113 to the display signal input from the main engine 130. This allows an image based on the RAW image generated in the live view process in S209 to be displayed on the display unit 113 as a live view image.

[0057] In S212, the system control unit 132 executes video shooting and recording processing. The video shooting and recording processing is a series of processes from applying high-quality development processing to RAW images acquired (captured) by the imaging unit 102 to recording the images on a predetermined recording medium.

[0058] In S213, the system control unit 122 determines whether a video recording end operation has been performed. That is, the system control unit 122 determines whether the user has pressed the video recording button 108 and issued an instruction to end video recording by pressing the video recording button 108. Note that the video recording end operation is not limited to pressing the video recording button 108, but also includes other operations that end video recording. If the system control unit 122 determines that a video recording end operation has been performed (YES in S213), the process proceeds to S221 in FIG. 2B. If the system control unit 122 determines that a video recording end operation has not been performed (NO in S213), the process returns to S209, and the main engine 130 performs live view processing again.

[0059] In S214, the system control unit 122 determines whether a first shutter switch (SW1) signal has been input. That is, the system control unit 122 determines whether the user has half-pressed the shutter button 107 to capture and record a still image, and whether a shooting preparation command has been issued by the first shutter switch (SW1) signal. If the system control unit 122 determines that a first shutter switch (SW1) signal has been input (YES in S214), the process proceeds to S215. If the system control unit 122 determines that a first shutter switch (SW1) signal has not been input (NO in S214), the process proceeds to S225 in FIG. 2B.

[0060] In S215, a startup process for the main engine 130 is executed. The system control unit 122 controls the power supply control unit 110 to instruct it to start supplying power to the main engine 130. That is, the power supply control unit 110 either removes the restriction on the power supplied to the main engine 130 or starts supplying power. The system control unit 122 also controls the system control unit 132 to execute a startup operation for the main engine 130.

[0061] In S216, the system control unit 122 determines whether a second shutter switch (SW2) signal has been input. That is, the system control unit 122 determines whether the user has fully pressed the shutter button 107 and issued a still image capture instruction via the second shutter switch (SW2) signal. If the system control unit 122 determines that a second shutter switch (SW2) signal has been input (YES in S216), the process proceeds to S217. If the system control unit 122 determines that a second shutter switch (SW2) signal has not been input (NO in S216), the process returns to S214.

[0062] In S217, a startup process is executed for the display system (functional units related to image display) related to the main engine 130. The system control unit 132 reads the setting data stored in the memory 137 and performs initialization to set various parameters for the display control unit 134 and the display device control unit 135.

[0063] In S218, the system control unit 132 executes still image shooting and recording processing. The still image shooting and recording processing is a series of processes from applying high-quality development processing to a RAW image acquired (captured) by the imaging unit 102 to recording the image on a predetermined recording medium. Here, the still image shooting and recording processing is performed based on camera settings related to shooting and recording that are set based on user operations, etc., and stored in memory 127. In other words, the still image shooting and recording processing is executed by reading image data from the imaging unit 102 in accordance with the image size for recording that is set as the camera setting related to shooting and recording.

[0064] In S219, a display destination ME switching process is executed. The system control unit 122 controls the display signal switching unit 112 to switch the internal selector of the display signal switching unit 112 so as to switch the display signal to be displayed on the display unit 113 to the display signal input from the main engine 130.

[0065] In S220, the system control unit 132 executes a preview process. The preview process by the main engine 130 is a process of displaying, as a preview image on the display unit 113 for a predetermined time, an image for recording obtained by the still image shooting and recording process (an image that has been developed and has not yet been compressed). This allows the image for recording that is processed and generated by the image processing unit 131 to be displayed as a preview image on the display unit 113. After the preview image has been displayed for the predetermined time, the process proceeds to S221 in FIG. 2B.

[0066] 2B, the system control unit 122 executes live view processing. The live view processing in S221 is the same as the live view processing in S205 described above.

[0067] In S222, a display destination FE switching process is executed. The display destination FE switching process is a process in which the display signal switching unit 112 switches the display signal input from the front engine 120 so as to output it to the display unit 113. The system control unit 122 controls the display signal switching unit 112 to switch the internal selector of the display signal switching unit 112 so as to switch the display signal to be displayed on the display unit 113 to the display signal input from the front engine 120. This allows the live view image generated in the live view process in S221 to be displayed on the display unit 113.

[0068] In S223, the system control unit 132 performs a process of terminating the display control unit 134 and the display device control unit 135. By terminating the display control unit 134 and the display device control unit 135, the output of the image display signal from the main engine 130 stops.

[0069] In S224, processing is executed to stop the main engine 130. The system control unit 122 controls the system control unit 132 to execute the operation to stop the main engine 130. Then, the system control unit 122 controls the power supply control unit 110 to instruct the power supply control unit 110 to stop the power supply to the main engine 130 (to limit the power supply to the main engine 130).

[0070] In S225, the system control unit 122 determines whether an instruction to end the operation of the digital camera 100 has been input. Specifically, the system control unit 122 determines whether the power switch 109 has been operated from on (ON) to off (OFF). Alternatively, if no operation has been performed on the digital camera 100 for a predetermined period of time, the system control unit 122 may determine that an instruction to end the operation of the digital camera 100 has been input (so-called sleep operation). If the system control unit 122 determines that an instruction to end the operation of the digital camera 100 has been input (YES in S225), the process proceeds to S226. If the system control unit 122 determines that an instruction to end the operation of the digital camera 100 has not been input (NO in S225), the process returns to S203.

[0071] In S226, system control unit 122 executes a process to stop front engine 120 including itself, and also executes a process to stop each of the other units of digital camera 100. As a result, the entire operation of digital camera 100 stops.

[0072] Next, the operation when the system control unit 122 determines in S204 of Fig. 2A that the operating mode is not the shooting mode but the playback mode will be described with reference to Fig. 3. Fig. 3 is a flowchart illustrating the operation of the digital camera 100 in the playback mode.

[0073] In S301, a startup process is executed for the main engine 130. The startup process for the main engine 130 in S301 is similar to the startup process for the main engine 130 in S207 in FIG. 2A. In S302, a startup process is executed for the display system (functional units related to image display) for the main engine 130. The startup process for the display system for the main engine 130 in S302 is similar to the startup process for the display system for the main engine 130 in S208 of FIG. 2A.

[0074] In S303, a playback process is executed. The playback process is a process of reading image data recorded on the recording medium 114 and displaying an image based on the read image data on the display unit 113. The system control unit 132 controls the recording and playback control unit 133 to read the image data from the recording medium 114, and controls the image processing unit 131 to perform image processing according to the format of the image data and generate display image data.

[0075] In S304, the system control unit 122 determines whether or not the display destination ME switching process in S305, which will be described later, has not been performed. That is, the system control unit 122 determines whether or not the display destination ME switching process in S305 has already been performed. If the system control unit 122 determines that the display destination ME switching process in S305 has not been performed (YES in S304), the process proceeds to S305. If the system control unit 122 determines that the display destination ME switching process has already been performed (NO in S304), the process proceeds to S306. In this way, the display destination ME switching process is performed only once when the ME startup process is performed.

[0076] In S305, a display destination ME switching process is executed. The display destination ME switching process in S305 is the same as the display destination ME switching process in S211 of FIG. 2A.

[0077] In S306, the system control unit 122 determines whether a playback end operation has been performed. That is, the system control unit 122 determines whether the user has performed an operation to end the playback process, such as an operation on the shutter button 107 related to still image shooting, an operation on the video recording button 108 related to video shooting, or a playback end button operation. If the system control unit 122 determines that a playback end operation has been performed (YES in S306), the process proceeds to S221 in FIG. 2B. If the system control unit 122 determines that a playback end operation has not been performed (NO in S306), the process returns to S303, and the playback process is performed again.

[0078] Next, an operation at the time of external output that is executed when the system control unit 122 determines that the external output function is enabled in S203 of Fig. 2A will be described with reference to Fig. 4. Fig. 4 is a flowchart illustrating the operation at the time of external output of the digital camera 100.

[0079] In S401, the system control unit 122 determines whether or not the external device 115 is connected via an external terminal (not shown) provided in the digital camera 100. If the system control unit 122 determines that the external device 115 is connected to the digital camera 100 (YES in S401), the process proceeds to S402. If the system control unit 122 determines that the external device 115 is not connected to the digital camera 100 (NO in S401), the process proceeds to S204 in FIG. 2A.

[0080] In S402, a startup process is executed for the main engine 130. The startup process for the main engine 130 in S402 is similar to the startup process for the main engine 130 in S207 in FIG. 2A. In S403, a startup process is executed for the display system (functional units related to image display) for the main engine 130. The startup process for the display system for the main engine 130 in S403 is similar to the startup process for the display system for the main engine 130 in S208 of FIG. 2A.

[0081] In S404, the system control unit 122 determines whether the operation mode of the digital camera 100 is the shooting mode. If the system control unit 122 determines that the operation mode is the shooting mode (YES in S404), the process proceeds to S405. If the system control unit 122 determines that the operation mode is not the shooting mode (NO in S404), the process proceeds to S501 in FIG. 5.

[0082] In S405, the system control unit 122 executes live view processing. The live view processing in S405 is processing of image data acquired from the imaging unit 102 to generate a live view image and display it on the external device 115. Similar to the live view processing in S205 of FIG. 2A , the live view processing in S405 is performed at a low frame rate or low resolution, regardless of the camera settings related to shooting and recording stored in the memory 127. In the live view processing in S405, the image data acquired from the imaging unit 102 is processed by the image processing unit 121 and transferred to the memory 137 of the main engine 130 via the memory 127 of the front engine 120. The system control unit 132 displays the live view image based on the image data transferred to the memory 137 on the external device 115 using the display control unit 134 and the display device control unit 135.

[0083] In S406, the system control unit 122 determines whether a moving image shooting operation has been performed. If the system control unit 122 determines that a moving image shooting operation has been performed (YES in S406), the process proceeds to S407. If the system control unit 122 determines that a moving image shooting operation has not been performed (NO in S406), the process proceeds to S225 in FIG. 2B.

[0084] In S407, the system control unit 132 executes live view processing. The live view processing in S407 is similar to the live view processing in S209 in FIG. 2A. In S408, the system control unit 132 executes the moving image shooting and recording process. The moving image shooting and recording process in S407 is similar to the moving image shooting and recording process in S212 of FIG.

[0085] In S409, the system control unit 122 determines whether or not a video shooting end operation has been performed. If the system control unit 122 determines that a video shooting end operation has been performed (YES in S409), the process proceeds to S410. If the system control unit 122 determines that a video shooting end operation has not been performed (NO in S409), the process returns to S407, and the main engine 130 performs live view processing again.

[0086] In S410, processing is executed to stop the main engine 130. The processing to stop the main engine 130 in S410 is similar to the processing to stop the main engine 130 in S224 in Fig. 2B. After the processing to stop the main engine 130 in S410 is completed, the processing proceeds to S225 in Fig. 2B.

[0087] Next, with reference to Fig. 5, an operation will be described in the case where the system control unit 122 determines in S404 of Fig. 4 that the operating mode is not the shooting mode but the playback mode. Fig. 5 is a flowchart illustrating the operation of the digital camera 100 in the playback mode during external output.

[0088] In S501, a startup process is executed for the main engine 130. The startup process for the main engine 130 in S501 is similar to the startup process for the main engine 130 in S207 in FIG. 2A. In S502, a playback process is executed, which is the same as the playback process in S303 in FIG.

[0089] In S503, the system control unit 122 determines whether a playback end operation has been performed. That is, the system control unit 122 determines whether the user has performed an operation to end the playback process, such as an operation on the shutter button 107 related to still image shooting, an operation on the video recording button 108 related to video shooting, or a playback end button operation. If the system control unit 122 determines that a playback end operation has been performed (YES in S503), the process proceeds to S221 in FIG. 2B. If the system control unit 122 determines that a playback end operation has not been performed (NO in S503), the process returns to S502, and the playback process is performed again.

[0090] According to the first embodiment, the digital camera 100 limits the power supply to the main engine 130 when the camera is in standby mode. Furthermore, the front engine 120 displays live view images processed at a low frame rate and low resolution on the display unit 113, regardless of the pixel count and frame rate settings of the video to be recorded, thereby reducing power consumption during live view display. This enables the digital camera 100 to reduce power consumption when the camera is in standby mode. Furthermore, when shooting and recording moving images, the restriction on the power supply to the main engine 130 is lifted to start up the main engine 130. The main engine 130 then processes the images at the frame rate and resolution for recording moving images set by the user, and outputs the resulting image data to the display unit 113 via the display signal switching unit 112, where it is displayed as a live view image. This makes it possible to display images being recorded during shooting.

[0091] Second Embodiment In the second embodiment, an example will be described in which the digital camera 100 is capable of simultaneously outputting a display signal (capable of displaying an image) to the display unit 113 and the external device 115. In the following, in the second embodiment, explanations of the same points as in the first embodiment will be omitted, and only points different from the first embodiment will be explained. Figures 6A and 6B are flowcharts explaining the overall operation of the digital camera 100 in the second embodiment. The operation when simultaneously outputting a display signal to the display unit 113 and the external device 115 will be explained with reference to the flowcharts of Figures 6A and 6B.

[0092] In S601, a start-up process is executed for the front engine 120. The start-up process for the front engine 120 in S601 is similar to the start-up process for the front engine 120 in S201 in FIG. 2A. In S602, a startup process is executed for the display system (functional unit related to image display) for the front engine 120. The startup process for the display system for the front engine 120 in S602 is the same as the startup process for the display system for the front engine 120 in S202 of FIG. 2A.

[0093] In S603, the system control unit 122 determines whether the external output function of the digital camera 100 is enabled. If the system control unit 122 determines that the external output function is enabled (YES in S603), the process proceeds to S604. If the system control unit 122 determines that the external output function is disabled (NO in S603), the process proceeds to S204 in FIG. 2A because simultaneous display signal processing is not performed.

[0094] In S604, a startup process is executed for the main engine 130. The startup process for the main engine 130 in S604 is similar to the startup process for the main engine 130 in S207 in FIG. 2A. In S605, a startup process is executed for the display system (functional units related to image display) for the main engine 130. The startup process for the display system for the main engine 130 in S605 is similar to the startup process for the display system for the main engine 130 in S208 of FIG. 2A.

[0095] In S606, the system control unit 122 determines whether the operation mode of the digital camera 100 is the shooting mode. If the system control unit 122 determines that the operation mode is the shooting mode (YES in S606), the process proceeds to S607. If the system control unit 122 determines that the operation mode is not the shooting mode (NO in S606), the process proceeds to S501 in FIG. 5.

[0096] In S607, the system control unit 122 of the front engine 120 executes live view processing. The live view processing during simultaneous external output is processing image data acquired from the imaging unit 102 to generate a live view image, and outputting the image data to both the display unit 113 and the external device 115. The live view processing in S607 is performed at a frame rate or resolution according to the camera settings for shooting and recording that are set based on user operations or the like and stored in the memory 127. In the live view processing in S607, an image based on the RAW image acquired from the imaging unit 102 and generated through processing by the image processing unit 121 is displayed on the display unit 113 using the display control unit 124, the display device control unit 125, and the display signal switching unit 112. The RAW image acquired from the imaging unit 102 is transferred to the memory 137 via the memory 127. The system control unit 132 displays the image based on the RAW image transferred to the memory 137 on the external device 115 as a live view image using the display control unit 134 and the display device control unit 135.

[0097] In S608, the system control unit 122 determines whether a moving image shooting operation has been performed. If the system control unit 122 determines that a moving image shooting operation has been performed (YES in S608), the process proceeds to S609. If the system control unit 122 determines that a moving image shooting operation has not been performed (NO in S608), the process proceeds to S614.

[0098] In S609, the system control unit 132 executes live view processing. The live view processing in S609 is similar to the live view processing in S209 in FIG. 2A.

[0099] In S610, the system control unit 122 determines whether or not the display destination ME switching process in S611, which will be described later, has not been performed. If the system control unit 122 determines that the display destination ME switching process in S611 has not been performed (YES in S610), the process proceeds to S611. If the system control unit 122 determines that the display destination ME switching process has already been performed (NO in S610), the process proceeds to S612. In this way, the display destination ME switching process is performed only once when the ME startup process is performed.

[0100] In S611, a display destination ME switching process is executed. The system control unit 122 controls the display signal switching unit 112 to switch the internal selector of the display signal switching unit 112 so as to switch the display signal to be displayed on the display unit 113 to the display signal input from the main engine 130. This allows an image based on the RAW image generated in the live view process in S609 to be displayed as a live view image on the display unit 113. Note that during simultaneous output, the system control unit 132 continues to output the display signal of the image to the external device 115 using the display control unit 134 and the display device control unit 135.

[0101] In S612, the system control unit 132 executes a moving image shooting and recording process. The moving image shooting and recording process in S612 is similar to the moving image shooting and recording process in S212 in FIG. 2A.

[0102] In S613, the system control unit 122 determines whether or not a video shooting end operation has been performed. If the system control unit 122 determines that a video shooting end operation has been performed (YES in S613), the process proceeds to S618 in Fig. 6B. If the system control unit 122 determines that a video shooting end operation has not been performed (NO in S613), the process returns to S609, and the main engine 130 performs live view processing again.

[0103] In S614, the system control unit 122 determines whether a second shutter switch (SW2) signal has been input. That is, the system control unit 122 determines whether the user has fully pressed the shutter button 107 and issued a still image capture instruction via the second shutter switch (SW2) signal. If the system control unit 122 determines that a second shutter switch (SW2) signal has been input (YES in S614), the process proceeds to S615. If the system control unit 122 determines that a second shutter switch (SW2) signal has not been input (NO in S614), the process proceeds to S621 in FIG. 6B.

[0104] In S615, the system control unit 132 executes a still image shooting and recording process. The still image shooting and recording process in S615 is similar to the still image shooting and recording process in S218 in Fig. 2A. In S616, a display destination ME switching process is executed. The display destination ME switching process in S616 is the same as the display destination ME switching process in S219 in FIG. 2A. In S617, the system control unit 132 executes preview processing. The preview processing in S617 is the same as the preview processing in S220 in Fig. 2A. After the preview image is displayed for a predetermined time in the preview processing, the process proceeds to S618 in Fig. 6B.

[0105] In S618 of Fig. 6B, the system control unit 122 executes live view processing. The live view processing in S618 is similar to the live view processing in S205 of Fig. 2A and S221 of Fig. 2B. In S619, a display destination FE switching process is executed. The display destination FE switching process in S619 is the same as the display destination FE switching process in S222 of FIG. 2B. In S620, the system control unit 132 performs a process of terminating the display control unit 134 and the display device control unit 135. The process of terminating the display control unit 134 and the display device control unit 135 in S620 is the same as the process of terminating the display control unit 134 and the display device control unit 135 in S223 of FIG. 2B.

[0106] In S621, the system control unit 122 determines whether or not an instruction to end the operation of the digital camera 100 has been input. If the system control unit 122 determines that an instruction to end the operation of the digital camera 100 has been input (YES in S621), the process proceeds to S622. If the system control unit 122 determines that an instruction to end the operation of the digital camera 100 has not been input (NO in S621), the process proceeds to S606.

[0107] In S622, processing is performed to stop the main engine 130. The processing to stop the main engine 130 in S622 is similar to the processing to stop the main engine 130 in S224 in FIG. 2B. In S623, the system control unit 122 executes processing to stop the front engine 120, including itself. The processing to stop the front engine 120 in S623 is the same as the processing to stop the front engine 120 in S226 in Fig. 2B. As a result, the entire operation of the digital camera 100 stops.

[0108] According to the second embodiment, when digital camera 100 is in simultaneous external output mode and is on standby for shooting, live view images that have been processed at a low frame rate and low resolution by front engine 120 regardless of the camera settings are displayed on display unit 113 and external device 115. This allows digital camera 100 to reduce power consumption while on standby for shooting. Furthermore, when shooting and recording moving images, the main engine 130 processes the images at the frame rate and resolution for recording the moving images set by the user, and outputs the resulting image data to the display unit 113 via the display signal switching unit 112, where it is displayed as a live view image. This makes it possible to display the image being recorded while shooting.

[0109] <Third embodiment> In the third embodiment, a configuration will be described that allows the user to switch whether or not to limit the power supply to the main engine 130 in a shooting standby state. The state in which the power supply to the main engine 130 is set to be limited is called a power saving mode. In the following, in the third embodiment, explanations of the same points as in the first embodiment will be omitted, and only points different from the first embodiment will be explained. FIG. 7 is a flowchart explaining the overall operation of the digital camera 100 in the third embodiment. The operation when an image display signal is output to the display unit 113 when the power saving mode is enabled or disabled will be explained with reference to the flowchart in FIG. 7.

[0110] In S701, a startup process for the front engine 120 is executed. The power supply control unit 110 supplies power to the front engine 120 in response to receiving a startup instruction from the power switch 109 after the power switch 109 is turned on. The system control unit 122 reads a startup program and parameters from the system memory 126 and executes the startup operation. Meanwhile, the power supply control unit 110 does not supply the power necessary for the main engine 130 to operate in a normal state (it limits the power supply to the main engine 130 or stops the power supply). Note that when the front engine 120 is started, the setting data stored in the memory 127 is set to disable the power saving mode. The user can set whether to enable or disable the power saving mode by operating the menu button 105, etc. Alternatively, it may be possible to set whether to enable or disable the power saving mode using a separate component of the operation unit 103.

[0111] In S702, a startup process is executed for the display system (functional units related to image display) for the front engine 120. The startup process for the display system for the front engine 120 in S702 is the same as the startup process for the display system for the front engine 120 in S202 of FIG. 2A.

[0112] In S703, the system control unit 122 determines whether the external output function of the digital camera 100 is enabled. If the system control unit 122 determines that the external output function is enabled (YES in S703), the process proceeds to S401 in Fig. 4. If the system control unit 122 determines that the external output function is disabled (NO in S703), the process proceeds to S704.

[0113] In S704, the system control unit 122 determines whether the operation mode of the digital camera 100 is the shooting mode. If the system control unit 122 determines that the operation mode is the shooting mode (YES in S704), the process proceeds to S705. If the system control unit 122 determines that the operation mode is not the shooting mode (NO in S704), the process proceeds to S301 in FIG. 3.

[0114] In S705, the system control unit 122 executes live view processing. The live view processing in S705 is similar to the live view processing in S205 in FIG. 2A.

[0115] In S706, the system control unit 122 determines whether the power saving mode of the digital camera 100 is enabled. The system control unit 122 reads the setting data stored in the system memory 126 and determines whether the power saving mode is enabled. If the system control unit 122 determines that the power saving mode is disabled, that is, that the setting does not limit the supply of power to the main engine 130 (NO in S706), the process proceeds to S707. On the other hand, if the system control unit 122 determines that the power saving mode is enabled (YES in S706), the process proceeds to S206 in FIG. 2A. Here, after the process proceeds to S206 in FIG. 2A, the system control unit 122 monitors whether the power saving mode has been canceled, and if the power saving mode has been canceled and the power saving mode has been set to disabled, the process proceeds to S707.

[0116] In S707, a startup process is executed for the main engine 130. The startup process for the main engine 130 in S707 is similar to the startup process for the main engine 130 in S207 of FIG. 2A. In S708, a startup process is executed for the display system (functional units related to image display) for the main engine 130. The startup process for the display system for the main engine 130 in S708 is similar to the startup process for the display system for the main engine 130 in S208 of FIG. 2A. In S709, the system control unit 132 executes live view processing. The live view processing in S709 is similar to the live view processing in S209 in FIG. 2A.

[0117] In S710, the system control unit 122 determines whether or not the display destination ME switching process in S711, which will be described later, has not been performed. If the system control unit 122 determines that the display destination ME switching process in S711 has not been performed (YES in S710), the process proceeds to S711. If the system control unit 122 determines that the display destination ME switching process has already been performed (NO in S710), the process proceeds to S712. In this way, the display destination ME switching process is performed only once when the ME startup process is performed.

[0118] In S711, a display destination ME switching process is executed. The display destination ME switching process in S711 is the same as the display destination ME switching process in S211 of FIG. 2A.

[0119] In S712, the system control unit 122 determines whether a moving image shooting operation has been performed. If the system control unit 122 determines that a moving image shooting operation has been performed (YES in S712), the process proceeds to S713. If the system control unit 122 determines that a moving image shooting operation has not been performed (NO in S712), the process proceeds to S715. In S713, the system control unit 132 executes a moving image shooting and recording process. The moving image shooting and recording process in S713 is similar to the moving image shooting and recording process in S212 of FIG. 2A.

[0120] In S714, the system control unit 122 determines whether or not a video recording end operation has been performed. If the system control unit 122 determines that a video recording end operation has been performed (YES in S714), the process proceeds to S221 in FIG. 2B. Note that after the process proceeds to S221 in FIG. 2B, if the system control unit 122 determines that an instruction to end the operation of the digital camera 100 has not been input in S225 in FIG. 2B (NO), the process proceeds to S703. If the system control unit 122 determines that a video recording end operation has not been performed (NO in S714), the process returns to S709, and the main engine 130 performs live view processing again.

[0121] In S715, the system control unit 122 determines whether a second shutter switch (SW2) signal has been input. That is, the system control unit 122 determines whether the user has fully pressed the shutter button 107 and issued a still image capture instruction via the second shutter switch (SW2) signal. If the system control unit 122 determines that a second shutter switch (SW2) signal has been input (YES in S715), the process proceeds to S716. If the system control unit 122 determines that a second shutter switch (SW2) signal has not been input (NO in S715), the process proceeds to S706.

[0122] In S716, the system control unit 132 executes a still image shooting and recording process. The still image shooting and recording process in S716 is similar to the still image shooting and recording process in S218 in Fig. 2A.

[0123] In S717, the system control unit 132 executes preview processing. The preview processing in S717 is the same as the preview processing in S220 of Fig. 2A. After the preview image is displayed for a predetermined time in the preview processing, the processing proceeds to S221 of Fig. 2B. Note that after the processing proceeds to S221 of Fig. 2B, if the system control unit 122 determines in S225 of Fig. 2B that an instruction to end the operation of the digital camera 100 has not been input (NO), the processing proceeds to S703.

[0124] According to the third embodiment, while the power saving mode is enabled, the digital camera 100 can reduce power consumption in a shooting standby state and display images being recorded during shooting, as in the first embodiment. When the power saving mode is disabled, the main engine 130 can process image data at the frame rate and resolution for recording moving images set by the user, and display the processed image data on the display unit 113 as a live view image.

[0125] (Another embodiment of the present invention) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0126] It should be noted that the above-described embodiments are merely examples of specific embodiments for carrying out the present invention, and the technical scope of the present invention should not be construed as being limited by these embodiments. In other words, the present invention can be carried out in various forms without departing from its technical concept or main features.

[0127] The disclosure of this embodiment includes the following configurations, methods, etc. (Configuration 1) An imaging means; a first integrated circuit that acquires image data from the imaging means and generates image data to be displayed on a display unit based on the image data acquired from the imaging means; a second integrated circuit that acquires image data from the imaging means via the first integrated circuit, records the image data acquired via the first integrated circuit on a recording medium, and generates image data to be displayed on the display unit, which corresponds to the image data recorded on the recording medium, based on the image data acquired from the first integrated circuit; power supply control means for controlling the supply of power to the second integrated circuit; a switching means for outputting the image data generated by the first integrated circuit or the image data generated by the second integrated circuit to the display unit; a control unit that controls the power supply control unit to limit the supply of power to the second integrated circuit in a shooting standby state, and controls the switching unit to output image data generated by the first integrated circuit to the display unit, The control means, in response to an instruction to record a moving image in the shooting standby state, releases the restriction on the power supply to the second integrated circuit by the power supply control means, and controls the switching means to switch the image data output to the display unit from image data generated by the first integrated circuit to image data generated by the second integrated circuit. (Configuration 2) 2. The imaging device according to configuration 1, wherein the image data generated by the first integrated circuit has at least one of a frame rate and a resolution lower than that of the image data generated by the second integrated circuit. (Configuration 3) the control means controls the imaging means in response to an instruction to record the moving image so as to acquire image data in accordance with settings related to the number of pixels and frame rate of the moving image for recording; 3. The imaging device according to configuration 1 or 2, characterized in that, in the shooting standby state, the imaging means is controlled to acquire image data with a predetermined number of pixels and frame rate, regardless of the settings for recording. (Configuration 4) the second integrated circuit reproduces image data from the recording medium, and generates image data to be displayed on the display unit based on the reproduced image data; The imaging device described in any one of configurations 1 to 3, characterized in that when reproducing image data recorded on the recording medium, the control means releases the restriction on the supply of power to the second integrated circuit by the power supply control means, and controls the switching means to output image data generated by the second integrated circuit based on the reproduced image data to the display unit. (Configuration 5) the power supply control means is capable of setting whether or not to limit the supply of power to the second integrated circuit; The imaging device described in any one of configurations 1 to 4, characterized in that the control means controls the switching means to output image data generated by the second integrated circuit to the display unit in a shooting standby state if the setting does not restrict the supply of power to the second integrated circuit. (Configuration 6) 6. The imaging device according to any one of configurations 1 to 5, wherein the switching means is located outside the first integrated circuit and the second integrated circuit, or inside the first integrated circuit. (Configuration 7) 7. The imaging device according to any one of configurations 1 to 6, wherein the control means is included in the first integrated circuit. (Method 1) A control method for an imaging device having an imaging means, a first integrated circuit that acquires image data from the imaging means and generates image data to be displayed on a display unit based on the image data acquired from the imaging means, and a second integrated circuit that acquires image data from the imaging means via the first integrated circuit, records the image data acquired via the first integrated circuit on a recording medium, and generates image data to be displayed on the display unit that corresponds to the image data recorded on the recording medium based on the image data acquired from the first integrated circuit, a power supply control step of controlling the supply of power to the second integrated circuit; a switching step of outputting the image data generated by the first integrated circuit or the image data generated by the second integrated circuit to the display unit; a control step of limiting the supply of power to the second integrated circuit in the power supply control step in a shooting standby state, and performing control so that image data generated by the first integrated circuit is output to the display unit, A control method for an imaging device, characterized in that, in the control step, in response to an instruction to record a moving image in the shooting standby state, the power supply control step releases the restriction on the supply of power to the second integrated circuit, and controls so that the image data to be output to the display unit is switched from image data generated by the first integrated circuit to image data generated by the second integrated circuit. (Program 1) a first integrated circuit that acquires image data from the imaging means and generates image data to be displayed on a display unit based on the image data acquired from the imaging means; and a second integrated circuit that acquires image data from the imaging means via the first integrated circuit, records the image data acquired via the first integrated circuit on a recording medium, and generates image data to be displayed on the display unit that corresponds to the image data recorded on the recording medium based on the image data acquired from the first integrated circuit, a power supply control step of controlling the supply of power to the second integrated circuit; a switching step of outputting the image data generated by the first integrated circuit or the image data generated by the second integrated circuit to the display unit; a control step of limiting the supply of power to the second integrated circuit in the power supply control step in a shooting standby state, and performing control so that image data generated by the first integrated circuit is output to the display unit; A program that performs control in the control step to release the restriction on the supply of power to the second integrated circuit in response to an instruction to record a moving image in the shooting standby state, and to switch the image data to be output to the display unit from image data generated by the first integrated circuit to image data generated by the second integrated circuit. [Explanation of symbols]

[0128] 100: Digital camera 102: Imaging unit 103: Operation unit 104: Mode switch 105: Menu button 106: Playback button 107: Shutter button 108: Video recording button 109: Power switch 110: Power supply control unit 111: Power supply 112: Display signal switching unit 113: Display unit 114: Recording medium 115: External device 120: Front engine 130: Main engine 121, 131: Image processing unit 122, 132: System control unit 133: Recording and playback control unit 124, 134: Display control unit 125, 135: Display device control unit 126, 127: System memory 127, 137: Memory

Claims

1. An imaging means; a first integrated circuit that acquires image data from the imaging means and generates image data to be displayed on a display unit based on the image data acquired from the imaging means; a second integrated circuit that acquires image data from the imaging means via the first integrated circuit, records the image data acquired via the first integrated circuit on a recording medium, and generates image data to be displayed on the display unit, which corresponds to the image data recorded on the recording medium, based on the image data acquired from the first integrated circuit; power supply control means for controlling the supply of power to the second integrated circuit; a switching means for outputting the image data generated by the first integrated circuit or the image data generated by the second integrated circuit to the display unit; a control unit that controls the power supply control unit to limit the supply of power to the second integrated circuit in a standby state, and controls the switching unit to output image data generated by the first integrated circuit to the display unit, The control means, in response to an instruction to record a moving image in the shooting standby state, releases the restriction on the supply of power to the second integrated circuit by the power supply control means, and controls the switching means to switch the image data output to the display unit from image data generated by the first integrated circuit to image data generated by the second integrated circuit.

2. 2. The imaging device according to claim 1, wherein the image data generated by the first integrated circuit has at least one of a frame rate and a resolution lower than that of the image data generated by the second integrated circuit.

3. the control means controls the imaging means in response to an instruction to record the moving image so as to acquire image data in accordance with settings related to the number of pixels and frame rate of the moving image for recording; 2. The imaging device according to claim 1, wherein, in the standby state, the imaging means is controlled so as to acquire image data with a predetermined number of pixels and frame rate, regardless of the settings for recording.

4. the second integrated circuit reproduces image data from the recording medium, and generates image data to be displayed on the display unit based on the reproduced image data; The imaging device described in claim 1, characterized in that, when reproducing image data recorded on the recording medium, the control means releases the restriction on the supply of power to the second integrated circuit by the power supply control means, and controls the switching means to output image data generated by the second integrated circuit based on the reproduced image data to the display unit.

5. the power supply control means is capable of setting whether or not to limit the supply of power to the second integrated circuit; The imaging device according to claim 1, characterized in that, when the control means is set not to restrict the supply of power to the second integrated circuit, the control means controls the switching means so that, in a shooting standby state, image data generated by the second integrated circuit is output to the display unit.

6. 2. The imaging device according to claim 1, wherein the switching means is located outside the first integrated circuit and the second integrated circuit, or inside the first integrated circuit.

7. 2. The imaging device according to claim 1, wherein the control means is included in the first integrated circuit.

8. A control method for an imaging device having an imaging means, a first integrated circuit that acquires image data from the imaging means and generates image data to be displayed on a display unit based on the image data acquired from the imaging means, and a second integrated circuit that acquires image data from the imaging means via the first integrated circuit, records the image data acquired via the first integrated circuit on a recording medium, and generates image data to be displayed on the display unit that corresponds to the image data recorded on the recording medium based on the image data acquired from the first integrated circuit, a power supply control step of controlling the supply of power to the second integrated circuit; a switching step of outputting the image data generated by the first integrated circuit or the image data generated by the second integrated circuit to the display unit; a control step of limiting the supply of power to the second integrated circuit in the power supply control step in a shooting standby state, and performing control so that image data generated by the first integrated circuit is output to the display unit, A control method for an imaging device, characterized in that, in the control process, in response to an instruction to record a moving image in the shooting standby state, the power supply control process releases the restriction on the supply of power to the second integrated circuit, and controls so that the image data to be output to the display unit is switched from image data generated by the first integrated circuit to image data generated by the second integrated circuit.

9. a first integrated circuit that acquires image data from the imaging means and generates image data to be displayed on a display unit based on the image data acquired from the imaging means; and a second integrated circuit that acquires image data from the imaging means via the first integrated circuit, records the image data acquired via the first integrated circuit on a recording medium, and generates image data to be displayed on the display unit that corresponds to the image data recorded on the recording medium based on the image data acquired from the first integrated circuit, a power supply control step of controlling the supply of power to the second integrated circuit; a switching step of outputting the image data generated by the first integrated circuit or the image data generated by the second integrated circuit to the display unit; a control step of limiting the supply of power to the second integrated circuit in the power supply control step in a shooting standby state, and of controlling the image data generated by the first integrated circuit to be output to the display unit; A program that, in the control step, controls the power supply control step to release the restriction on the supply of power to the second integrated circuit in response to an instruction to record a moving image in the shooting standby state, and controls the image data to be output to the display unit to be switched from image data generated by the first integrated circuit to image data generated by the second integrated circuit.

Images