JP2013250341A - Display control device, and method of controlling display control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display control device which can reduce deterioration in image quality in the case of changing backlight brightness.SOLUTION: A display control device controls a display device including light source means and transmission means that transmits light from the light source means. The display control device includes image acquiring means, and control means for controlling, on the basis of an image obtained by the image acquiring means, brightness of the light source means in the display device and transmittance of the transmission means. The control means changes followability of a change in brightness of the light source means to a change in the image, depending on operation mode of the display control device.

Description

  The present invention relates to a display control device and a control method for the display control device.

  Conventionally, a liquid crystal display device is known as a display control device. A liquid crystal display device is generally composed of a backlight and a liquid crystal panel capable of adjusting the light transmittance. In recent years, some of these display control devices have been able to control the transmittance of a liquid crystal panel and the luminance of a backlight in accordance with a display image. For example, by reducing the luminance of the backlight and increasing the transmittance of the liquid crystal panel so as to compensate for the luminance reduction, it is possible to reduce the power consumption of the backlight while displaying an equivalent image. is there. Such backlight control is called active backlight control.

  As a technique related to such a technique, conventionally, as in Patent Document 1, for example, a liquid crystal panel that displays an image based on an input video signal and a light source that illuminates the liquid crystal panel are included, In a liquid crystal display control device that controls the light emission luminance of a light source based on the above, a display control device that variably controls the follow-up of the light emission luminance of a light source with respect to a change in the feature amount of an input video signal according to the genre of the video is disclosed. . In Patent Document 1, for example, the follow-up performance of the light emission luminance of the light source with respect to the change in the feature amount of the input video signal is slow when the genre is “movie” and fast when the genre is “golf”.

JP 2007-143122 A

  However, in Patent Document 1, the followability is constant when images of the same genre are displayed. Therefore, for example, when the followability of the backlight luminance control is fast, if an image in which the brightness of the backlight changes greatly is displayed, it may be visually recognized by the user as flicker. For example, when the follow-up performance of the backlight luminance control is slow, when an image whose gradation changes gradually is displayed, the noise on the ripples may be caused by a timing shift from the transmittance control of the liquid crystal panel. It was sometimes displayed.

  In view of such a problem, an object of the present invention is to provide a display control device capable of reducing image quality degradation when changing the brightness of a backlight.

The display control device of the present invention is a display control device that controls a display device having a light source unit and a transmission unit that transmits light from the light source unit, and is obtained by the image acquisition unit and the image acquisition unit. Control means for controlling the brightness of the light source means in the display device and the transmittance of the transmissive means based on the image;
The control means changes the followability of the brightness change of the light source means with respect to the change of the image according to the operation mode of the display control device.

  According to the present invention, it is possible to reduce image quality degradation when changing the brightness of a backlight.

It is a figure which shows the structure of the imaging device 100 of a present Example. It is a figure which shows the operation | movement flow of the imaging device 100 of a present Example. It is a figure which shows the brightness | luminance change when the follow-up property of backlight brightness | luminance is early. It is a figure which shows the luminance change in case the follow-up property of backlight luminance is slow, and the gradation change of an image.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments do not limit the invention according to the scope of claims, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention.

  In the following embodiments, an image pickup apparatus will be described as an example of a display control apparatus. However, the present invention is not limited to an image pickup apparatus, and may be any apparatus that can display an image. Applicable.

  Note that each functional block described in the present embodiment is not necessarily separate hardware. That is, for example, the functions of some functional blocks may be executed by one piece of hardware. In addition, the function of one functional block or the functions of a plurality of functional blocks may be executed by some hardware linked operations.

[First embodiment]
In the present embodiment, an imaging apparatus capable of displaying an image on a display unit having a liquid crystal panel and a backlight will be described as an example of a display control apparatus. In this embodiment, a white light source such as a cold cathode fluorescent lamp (CCFL) or a white light emitting diode (white LED) will be described as an example of the backlight. However, any light source may be used. . In addition, although a liquid crystal panel is used to control the light transmittance of the backlight, any device can be used as long as it can control the amount of light provided to the user. For example, as long as the transmittance is controlled like a liquid crystal panel, the physical shutter opening time may be controlled. Moreover, the micromirror device etc. which control the time which reflects light in the user side may be sufficient. That is, when a micromirror device is used, the reflection time can be controlled by changing the image signal. Accordingly, the transmittance of the liquid crystal in the following description is read as the reflectance when a micromirror device is used.

  In the present embodiment, the display unit is provided in the imaging device, but may be a separate body.

  The imaging apparatus of the present embodiment has a plurality of modes such as a moving image capturing mode, a still image capturing mode, a moving image playback mode, a still image playback mode, and a menu display mode. In the moving image reproduction mode, an index screen for selecting a plurality of moving image files is displayed on the display unit, the selected moving image file is reproduced, and an image of the moving image file is displayed on the display unit. During playback of a moving image file, normal speed playback, pause, frame advance, slow playback, high speed playback, reverse playback, reverse slow playback, and reverse high speed playback are performed. Also in the still image reproduction mode, an index screen for selecting a plurality of still image files is displayed on the display unit, and the selected still image file is reproduced and an image is displayed on the display unit. In addition, the imaging apparatus according to the present embodiment changes the followability of the backlight luminance in the display unit. The followability can be set in at least two stages, but may be set in multiple stages.

  Note that by changing the dynamic range of the image signal following the change in the luminance of the backlight, it is possible to provide a stable image to the user regardless of the change in the luminance of the backlight.

  In addition, the imaging apparatus according to the present embodiment makes the backlight luminance follow-up faster in the still image reproduction mode than in the still image imaging mode, for example. In the still image playback mode, the follow-up performance of the backlight luminance is made faster than in the moving image capturing mode or the moving image playback mode.

  In addition, in the moving image playback mode, for example, in the moving image playback mode, the imaging apparatus according to the present embodiment has a slower backlight luminance follow-up than during moving image pause, frame advance, or slow playback. To do.

  In addition, the imaging apparatus according to the present embodiment, for example, analyzes a motion vector of a moving image that is being played back in the moving image playback mode, and detects a motion that is greater than or equal to a predetermined amount when a motion that is greater than or equal to a predetermined amount is not detected. Decrease the brightness tracking.

  Hereinafter, such an imaging apparatus will be described.

  FIG. 1 is a block diagram illustrating a configuration of the imaging apparatus according to the present exemplary embodiment.

  The imaging apparatus 100 according to the present exemplary embodiment includes a CPU 101, a RAM 102, a flash ROM 103, and an operation unit 104. In addition, the imaging apparatus 100 includes an imaging unit 110, an image processing unit 111, an audio input unit 120, an audio processing unit 121, an image output unit 132, a recording medium 140, a recording / playback unit 141, a communication unit 150, and an encoding / decoding processing unit. 160. In addition, the imaging apparatus 100 includes a liquid crystal panel 170, a backlight 171, a backlight driver 172, a ratio control unit 173, and a backlight control unit 174. The imaging device 100 may be of any size. For example, when the imaging device 100 is portable and is driven by a battery as a power source, the imaging device 100 can be driven by power saving. Time reduction can be suppressed.

  CPU is an abbreviation for Central Processing Unit. RAM is an abbreviation for Random Access Memory.

  In the imaging apparatus 100 of the present embodiment, the CPU 101 develops various programs recorded in the flash ROM 103 using the RAM 102 as a work memory, and controls each block of the imaging apparatus 100 according to the program. The operation unit 104 includes switches for inputting various operations such as a power button, a record button, a zoom adjustment button, an autofocus button, a menu display button, a mode switch, and a determination button. Further, any type of operation element such as a cursor key, a pointing device, a touch panel, or the like may be used. The operation unit 104 transmits an operation signal to the CPU 101 when these keys, buttons, and touch panel are operated by the user. Each operation member of the operation unit 104 is appropriately assigned a function for each scene by selecting and operating various function icons displayed on the display unit, and functions as various function buttons. Examples of the function buttons include an end button, a return button, an image advance button, a jump button, a narrowing button, and an attribute change button. For example, when a menu button is pressed, various setting menu screens are displayed on the display unit. The user can make various settings intuitively using the menu screen displayed on the display unit, and the four-way buttons and the SET button. Note that the operation unit 104 may be a touch panel that can detect contact with the display unit. The touch panel may be any of various types of touch panels such as a resistive film method, a capacitance method, a surface acoustic wave method, an infrared method, an electromagnetic induction method, an image recognition method, and an optical sensor method. .

  The imaging unit 110 converts an optical image of a subject captured by a lens into an image signal using an imaging element such as a CCD sensor or a CMOS sensor by controlling a light amount by a diaphragm, and converts the obtained analog image signal into a digital image signal. And temporarily stored in the RAM 102. The digital image signal stored in the RAM 102 is then transmitted to the image processing unit 111. The image processing unit 111 performs an image quality adjustment process for adjusting the white balance, color, brightness, and the like of the digital image signal based on a setting value set by the user or a setting value automatically determined from the characteristics of the image. The digital image signal that has been processed is stored in the RAM 102 again. In addition, the digital image signal that has undergone image quality adjustment processing or has not been processed is transmitted to a ratio control unit 173 described later. At the time of reproduction, the image processing unit 111 reads the image quality of the image data included in the still image file or the moving image file read from the recording medium 140 by the recording / reproducing unit 141 and decoded by the encoding / decoding processing unit 160. Make adjustments. Then, the digital image signal is transmitted to a ratio control unit 173 and an image output unit 132 which will be described later.

  At the time of recording, the encoding / decoding processing unit 160 performs image compression processing based on the digital image signal processed by the image processing unit 111 and stored in the RAM 102 to generate compressed moving image data and still image data. Then, a process of temporarily storing in the RAM 102 is performed. Further, at the time of reproduction, a process is performed in which the compressed moving image data and still image data of the image file read from the recording medium 140 is decoded to extract a digital image signal and stored in the RAM 102.

  The audio input unit 120 collects (collects) sounds around the imaging apparatus 100 using, for example, a built-in omnidirectional microphone or an external microphone connected via an audio input terminal, and acquires the acquired analog The audio signal is converted into a digital signal and temporarily stored in the RAM 102. The digital audio signal stored in the RAM 102 is then transmitted to the audio processing unit 121. At the time of recording, the audio processing unit 121 performs processing such as level optimization processing and noise reduction processing on the digital audio signal stored in the RAM 102, and stores the processed digital audio signal in the RAM 102 again. Moreover, the process which compresses an audio | voice signal is performed as needed. As for the audio compression method, since a known general audio compression method such as AC3 or AAC is used, description thereof is omitted. At the time of reproduction, a process of decoding compressed audio data included in an audio file or a moving image file read from the recording medium 140 by the recording / reproducing unit 141 is also performed.

  In the recording / playback unit 141, when recording a moving image, various types of data such as the compressed moving image data generated by the encoding / decoding processing unit 160, the audio data generated by the audio processing unit 121, and the shooting date are stored in the RAM 102. Along with the information, it is written in the recording medium 140 as a moving image file. At the time of recording a still image, the still image data stored in the ROM 102 is recorded on the recording medium 140 as a still image file together with various information such as the shooting date. When recording a moving image file on the recording medium 140, a data stream composed of compressed moving image data and audio data is formed and sequentially recorded on the recording medium 140, and a file header or the like is added to a file such as FAT or exFAT. Record a video file on a recording medium in a form that conforms to the format. Further, at the time of reproduction, the moving image file and still image file recorded on the recording medium 140 are read according to the aforementioned file format. The read moving image file and still image file are analyzed for headers by the CPU 101, and compressed moving image data and still image data are extracted. The extracted compressed moving image data and still image data are stored in the RAM 102 and decoded by the encoding / decoding processing unit 160.

  Further, the recording medium 140 may be a recording medium built in the imaging apparatus or a removable recording medium. For example, the recording medium includes all types of recording media such as a hard disk, an optical disk, a magneto-optical disk, a CD-R, a DVD-R, a magnetic tape, a nonvolatile semiconductor memory, and a flash memory. When using removable recording media, the recording / reproducing unit 141 includes an interface for receiving the removable recording media.

  The communication unit 150 transmits and receives control signals, moving image files, still image files, various data, and the like with an external device different from the imaging device 100, and can be connected regardless of wired connection or wireless connection. It is. Note that any communication method may be used.

  Note that the image processing unit 111, the encoding / decoding processing unit 160, the audio processing unit 121, and the recording / reproducing unit 141 of the present embodiment may be a microcomputer equipped with a program for executing the above-described processes. Alternatively, the CPU 101 may execute a program for executing the above-described processing recorded in the flash ROM 103 on the RAM 102.

  Next, the display system will be described.

  The liquid crystal panel 170 is a liquid crystal element capable of controlling the light transmittance, and one color pixel is constituted by sub-pixels composed of a plurality of color pixels. For example, the liquid crystal panel 170 has subpixels of red pixels, green pixels, and blue pixels. In another example, the liquid crystal panel 170 may be a red pixel, a green pixel, a blue pixel, or a white pixel. The liquid crystal panel 170 can control the light transmittance of each pixel. For example, the transmittance is controlled by sandwiching liquid crystal oriented in a certain direction by two polarizing plates whose polarization directions are shifted by 90 degrees and applying a predetermined voltage to the liquid crystal corresponding to each pixel. The liquid crystal panel 170 of this embodiment controls the transmittance of each pixel based on the RGB value output from the ratio control unit 173 described later. The RGB value is a signal obtained by the ratio control unit 173 changing the dynamic range of the input digital image signal.

  The backlight 171 provides light to the liquid crystal panel 170 and uses, for example, a white light source such as a cold cathode fluorescent lamp (CCFL) or a white light emitting diode (white LED). The amount of light of the backlight 171 is controlled by the backlight driver 172. In this embodiment, the backlight driver 172 determines the brightness of the backlight 171 according to the “BL control signal” from the backlight control unit 174. To control. The control of the amount of light of the backlight 171 differs depending on the type of light source used. For example, the brightness is controlled by applying a voltage proportional to the backlight luminance ratio or passing a current proportional to the backlight luminance ratio. be able to. Further, when the backlight is an LED or the like, it is also possible to control the brightness by changing the duty ratio by pulse width modulation (PWM). Further, when the brightness of the backlight light source has a non-linear characteristic, the desired brightness can be obtained by controlling the brightness of the backlight by obtaining the applied voltage or applied current to the light source from the backlight luminance rate using a lookup table. There is also a way to control it.

  In the following description, a unit including the liquid crystal panel 170, the backlight 171 and the backlight driver 172 may be referred to as a display unit.

  The ratio control unit 173 acquires a digital image signal (image acquisition) from the image processing unit 111 under the control of the CPU 101, and controls the liquid crystal panel 170 and the backlight driver 172 based on the acquired digital image signal. The display control unit can perform ON / OFF control of image display of the liquid crystal panel 170 under the control of the CPU 101.

  The ratio control unit 173 performs image analysis of the input digital image signal, and determines a backlight emission ratio (“BL value”) in the backlight 172. Here, the backlight emission ratio is, for example, 100% emission when displaying a white image, that is, when the transmittance of each of the red pixel, the green pixel, and the blue pixel is maximized and the backlight luminance is maximized. It is specified as a ratio. That is, the case where the backlight emission ratio is 50% indicates half the maximum luminance. In the present embodiment, for example, the maximum value of the luminance of the image signal, the average luminance, the frequency of luminance greater than a predetermined threshold level, and the like are detected as the characteristic amount of the input digital image signal, and according to the characteristic amount. The “BL value” is determined. Then, gradation conversion of the input digital image signal is performed according to the calculated BL value, and the output RGB value is transmitted to the liquid crystal panel 170. For example, when the “BL value” is decreased, gradation conversion is performed to increase the dynamic range of the image signal.

  The calculation method of the light emission ratio “BL value” of the backlight by image analysis of the input digital image signal here is based on the maximum value and average value (APL) of the luminance and gradation value of the input digital image signal. However, the present invention is not limited to this, and various “BL value” determination methods and gradation conversion methods of digital image signals can be applied.

  Here, an example of the method for determining the light emission ratio “BL value” of the backlight and the gradation conversion method of the digital image signal will be described.

  For example, a histogram of the input digital image signal is created, and the gradation that is a predetermined ratio (for example, exceeds 90%) is obtained by counting from the smaller side of the gradation of each pixel included in the digital image signal. Then, the gradation conversion is performed by regarding that the obtained predetermined ratio of gradations is the maximum gradation. Then, the luminance of the backlight is calculated from the determined predetermined ratio of gradations and the ratio of the maximum gradation of the image signal.

  For example, when it is determined that 90% of pixels are included in the 127th gradation out of 255 gradations, the dynamic range of the digital image signal is expanded so that the 127th gradation is converted to 255 gradations. . In this case, each pixel value of the digital image signal is converted to about twice. By doing so, the backlight luminance can be reduced by about 50% compared to the case where gradation conversion and backlight adjustment are not performed.

  That is, in this example, gradation conversion is performed according to the feature amount of the digital image signal to determine the light emission ratio “BL value” of the backlight. As a matter of course, the light emission ratio “BL value” of the backlight may be determined first, and gradation conversion may be performed based on the “BL value”.

  When the liquid crystal panel 170 is a red pixel, a green pixel, a blue pixel, or a white pixel, a different calculation method is performed. For example, the image of the input digital image signal is analyzed, and the most frequently used gradation of each of the red component, the green component, and the blue component in the display screen of one screen is determined. For example, assume that the red component has 180 gradations, the green component has 100 gradations, and the blue component has 120 gradations. Then, in this example, the minimum value of the determined gradation values of the red component, the green component, and the blue component is obtained, and there are 100 gradations of the green component. Next, a predetermined ratio of the minimum gradation is assigned to the white component. For example, if the setting is such that 50% of the minimum gradation is assigned to the white component, in this example, 50 gradations out of 100 gradations of the green component are assigned to the white component. As a result, 50 gradations for the red component and the blue component are assigned to the white component, and the red component is assigned with 130 gradations, the green component is 50 gradations, the blue component is 70 gradations, and the white component is 50 gradations. It can be carried out. When performing such gradation conversion, the dynamic range is expanded and the backlight brightness is reduced compared to the display with only red, green, and blue pixels depending on the gradation assigned to the white component. Can be made. In this case, if the maximum gradation of each color is 255 gradations, each gradation is 50/255, the brightness of the backlight is reduced by about 20%, and the gradation value of each gradation is increased by 20%. Become.

  As described above, even when a liquid crystal panel of red pixels, green pixels, blue pixels, and white pixels is used, the backlight emission ratio “BL value” and gradation conversion processing can be performed.

  That is, also in this example, gradation conversion is performed according to the feature amount of the digital image signal to determine the light emission ratio “BL value” of the backlight. As a matter of course, the light emission ratio “BL value” of the backlight may be determined first, and gradation conversion may be performed based on the “BL value”.

  The backlight control unit 174 controls the brightness of the backlight 171 by transmitting a backlight control signal to the backlight driver 172. The backlight control signal “BL control signal” controls the backlight driver 172 so that the backlight 171 emits light at a luminance based on the backlight emission ratio “BL value” calculated by the ratio control unit 173. Control signal.

  Next, backlight luminance and gradation conversion followability will be described. For example, T1 shown in FIG. 3 indicates the followability of the backlight luminance when the display is switched from the state where the image A is displayed to the image B, and the case where the display is switched from the state where the image B is displayed to the image A. This shows the followability of backlight luminance. Also, T2 shown in FIG. 4 indicates the followability of the backlight luminance when the display is switched from the state in which the image C is displayed to the image D.

  In this embodiment, T1 and T2 are referred to as “Dimming time”.

  In the example of FIG. 3, for example, T1 is, for example, 66 milliseconds corresponding to the display time of 2 frames. In the example of FIG. 4, for example, T1 is, for example, 330 milliseconds corresponding to the time of 10 frames. That is, T1 <T2.

  In the imaging apparatus according to the present embodiment, it is possible to switch between a first setting with a fast follow-up of backlight luminance and a second setting with a follow-up of backlight brightness slower than the first setting. . Note that the imaging apparatus according to the present embodiment can switch not only in two stages but also in multiple stages as the follow-up switching. For example, T1 is an example of a first setting with fast followability, and T2 is an example of a second setting with slow followability. In the present embodiment, the setting values for performing these settings are referred to as “Dimming time setting values”.

  When the first setting with fast follow-up is performed, for example, the ratio control unit 173 refers to the feature amount of the image of the past two frames, and sets the backlight emission ratio according to the feature amount of the image. Decide and perform tone conversion. On the other hand, when the second setting with slow follow-up is performed, for example, the ratio control unit 173 refers to the feature amount of the image of the past 10 frames, and emits backlight according to the feature amount of the image. The ratio is determined and gradation conversion is performed. For example, in the first setting with fast followability, the weighting amount for the feature amount of the past frame is lowered, and in the second setting with slow followability, the weighting amount for the feature amount of the past frame is increased. May be.

  In the imaging apparatus 100 of the present embodiment, the CPU 101 transmits a “Dimming time setting value” for setting the “Dimming time” to the ratio control unit 173 to control the followability of the backlight luminance. As described above, when the backlight luminance is switched, gradation conversion of the digital image signal is also performed. Therefore, the “Dimming time” can also be said to be a follow-up property of the gradation conversion. That is, in the ratio control unit 173, the follow-up property of the tone conversion is switched together with the follow-up property of the backlight luminance. The ratio control unit 173 performs determination of the backlight luminance ratio “BL value” and gradation conversion of the digital image signal with the followability set by the “Dimming time set value”.

  In the present embodiment, for example, in the still image playback mode, the CPU 101 sets the “Dimming time setting value” in proportion to the mode of the imaging device so that the follow-up performance of the backlight brightness is faster than in the still image capturing mode. It transmits to the control part 173. Further, in the still image reproduction mode, “Dimming time setting value” is transmitted to the ratio control unit 173 according to the mode of the imaging device so that the follow-up performance of the backlight luminance is faster than the moving image imaging mode or the moving image reproduction mode. That is, when the operation mode is a mode for displaying a still image, the “Dimming time setting value is set so that the follow-up of the change in the luminance of the backlight is faster than in a mode other than the mode for displaying a still image. Is transmitted to the ratio control unit 173.

  In this embodiment, for example, in the moving image playback mode, during normal playback of a moving image, the follow-up performance of the backlight luminance is made slower than when the moving image is paused, during frame advance, or during slow playback. Therefore, the CPU 101 transmits “Dimming time setting value” corresponding to the playback state of the moving image in the moving image playback mode to the ratio control unit 173.

  Hereinafter, a specific operation of the imaging apparatus 100 according to the present embodiment will be described.

  First, when mode switching is instructed by the mode switching switch of the operation unit 104 of the imaging apparatus 100 according to the present exemplary embodiment, the CPU 101 can switch the operation mode. For example, the imaging apparatus 100 according to the present embodiment has a plurality of modes such as a moving image capturing mode, a still image capturing mode, a moving image playback mode, a still image playback mode, and a menu display mode. Furthermore, as a mode included in the still image capturing mode, there are an auto shooting mode, an auto scene discrimination mode, a manual mode, various scene modes for shooting settings for each shooting scene, a program AE mode, a custom mode, and the like. In addition, a plurality of sub modes may be prepared in the moving image capturing mode, the still image reproduction mode, and the moving image reproduction mode. When a changeover switch for displaying the menu screen is operated, the CPU 101 switches to a mode for displaying the menu screen on the display unit. In the still image capturing mode and the moving image capturing mode, the digital image signal obtained by the image capturing unit 110 is transmitted to the display system without being processed or processed by the image processing unit 111, and an image being captured is displayed. In the still image reproduction mode and the moving image reproduction mode, a moving image file or a still image file image reproduced from the recording medium 140 by the recording / reproducing unit 141 is transmitted to the display system, and an image of each file is displayed. In the mode for displaying the menu screen, the CPU 101 transmits the digital image signal recorded in the flash ROM 103 or the RAM 102 to the display system to display the menu screen.

  Further, in the moving image reproduction mode, an index screen for selecting a plurality of moving image files can be displayed on the display unit, the selected moving image file can be reproduced, and an image of the moving image file can be displayed on the display unit. During playback of a moving image file, normal speed playback, pause, frame advance, slow playback, high speed playback, reverse playback, reverse slow playback, and reverse high speed playback can be performed for the video file. Also in the still image reproduction mode, an index screen for selecting a plurality of still image files can be displayed on the display unit, and the selected still image file can be reproduced and an image can be displayed on the display unit.

  The control operation of the image pickup apparatus 100 according to the present embodiment described below is executed when the CPU 101 develops in the RAM 102 a control program for the image pickup apparatus recorded in the flash ROM 103 or the like. FIG. 2 shows a control operation of the imaging apparatus 100 of the present embodiment.

  First, when the power is turned on, the CPU 101 of the imaging apparatus 100 of the present embodiment determines the current operation mode (S201).

  If the CPU 101 determines that the still image recording mode or the moving image recording mode is set as a result of the determination in S201, the CPU 101 sets the “Dimming time setting value” to a second setting with a slow follow-up property (S202).

  On the other hand, if the CPU 101 determines that the index screen is being displayed in the still image playback mode, the menu screen display mode, the still image playback mode, or the movie playback mode as a result of the determination in S201, the CPU 101 sets the “Dimming time set value” to the follow-up property. The first setting is fast (S203).

  If the result of determination in S201 is that it is determined that the video playback mode is in effect, the playback operation is determined. In this embodiment, it is determined whether or not normal speed reproduction is performed (S204).

  If it is determined as a result of the determination in S204 that normal speed reproduction is being performed, the CPU 101 sets the “Dimming time setting value” to a second setting with a slow follow-up property (S202).

  On the other hand, if the CPU 101 determines that normal speed reproduction is not performed as a result of the determination in S204, the CPU 101 sets the “Dimming time setting value” to the first setting with fast follow-up (S203). The case where normal speed playback is not performed is, for example, pause, frame advance, slow playback, high speed playback, reverse playback, reverse slow playback, reverse high speed playback, and the like.

  Next, the CPU 101 determines whether or not a power-off instruction has been input (S205). If a power-off instruction has been input, the process ends. If the power-off instruction has not been input, the process of S201 is performed again.

  As described above, in the imaging apparatus 100 according to the present embodiment, the followability of the change in backlight luminance is changed according to the mode of the imaging apparatus 100. Therefore, image degradation can be reduced in each mode.

  That is, in the moving image recording mode, the still image recording mode, and the moving image normal speed reproduction in the moving image reproduction mode, the followability of the change in backlight luminance is slowed. Therefore, the occurrence of flicker can be suppressed. In these operation modes, since there is a high possibility that a moving image is displayed, there is almost no possibility of occurrence of ripple noise. Further, in the still picture playback mode, menu display mode, moving picture playback mode, and still picture playback mode index screen, the follow-up performance of the change in backlight luminance is fast, so that ripple noise does not occur. In these operation modes, since a still image is displayed, there is almost no possibility of occurrence of flicker.

  In the present embodiment, in the moving image playback mode, the first setting has a fast follow-up except for the normal playback. However, in the moving image playback mode, the “Dimming time setting value” "May be set as the second setting with low follow-up performance.

  In the present embodiment, the “Dimming time set value” is set to the first setting with fast follow-up while the index screen is displayed. However, even if the index screen is displayed in the moving image playback mode, the “Dimming time setting value” is set to the second setting that is slow to follow, and in the still image playback mode, “Dimming” is displayed even if the index screen is displayed. The “time setting value” may be the first setting with fast follow-up.

  Further, the “Dimming time set value” may be determined using the motion vector. That is, when a motion vector of a moving image being reproduced is analyzed and a motion exceeding a predetermined value is detected, the “Dimming time setting value” is set to a second setting with a slow follow-up property. The “Dimming time set value” is set as the first setting with fast followability. Specifically, the motion vector of the target pixel is detected from the difference between a plurality of frames of the input image. Then, when the magnitude of the motion vector exceeds a predetermined threshold level, it is determined that there is a predetermined level or more, and when the magnitude of the motion vector is smaller than the predetermined threshold level, the level of motion greater than the predetermined level is detected. Judge that there is no. The motion vector analysis may be performed only in the moving image recording mode, the still image recording mode, and the moving image reproduction mode.

  The imaging apparatus 100 according to the present embodiment may have a mode for displaying an image input from an external apparatus on the display control apparatus. In this case, the motion vector of the image input from the external device is analyzed, and when a motion exceeding a predetermined value is detected, the “Dimming time setting value” is set as the second setting with a slow follow-up property, and the motion exceeding the predetermined value is detected. If not detected, the “Dimming time set value” is set as the first setting with fast follow-up.

  In this embodiment, the image pickup apparatus is described as an example of the position of the display control apparatus. However, for example, any apparatus may be used as long as the apparatus can display an image on the display control apparatus. . For example, any device such as a personal computer, a PDA, a game machine, an electronic book reader, a printer, or a digital photo frame may be used.

  The present invention has been described in detail based on the preferred embodiments thereof, but the present invention is not limited to these specific embodiments, and various forms within the scope of the present invention are also included in the present invention. included. A part of the above-described embodiments may be appropriately combined.

[Other embodiments]
The above-described embodiments can also be realized in software by a computer of a system or apparatus (or CPU, MPU, etc.). Accordingly, the computer program itself supplied to the computer in order to implement the above-described embodiment by the computer also realizes the present invention. That is, the computer program itself for realizing the functions of the above-described embodiments is also one aspect of the present invention.

  The computer program for realizing the above-described embodiment may be in any form as long as it can be read by a computer. For example, it can be composed of object code, a program executed by an interpreter, script data supplied to the OS, but is not limited thereto. A computer program for realizing the above-described embodiment is supplied to a computer via a storage medium or wired / wireless communication. Examples of the storage medium for supplying the program include a magnetic storage medium such as a flexible disk, a hard disk, and a magnetic tape, an optical / magneto-optical storage medium such as an MO, CD, and DVD, and a nonvolatile semiconductor memory.

  As a computer program supply method using wired / wireless communication, there is a method of using a server on a computer network. In this case, a data file (program file) that can be a computer program forming the present invention is stored in the server. The program file may be an executable format or a source code. Then, the program file is supplied by downloading to a client computer that has accessed the server. In this case, the program file can be divided into a plurality of segment files, and the segment files can be distributed and arranged on different servers. That is, a server apparatus that provides a client computer with a program file for realizing the above-described embodiment is also one aspect of the present invention.

  In addition, a storage medium in which the computer program for realizing the above-described embodiment is encrypted and distributed is distributed, and key information for decrypting is supplied to a user who satisfies a predetermined condition, Installation may be allowed. The key information can be supplied by being downloaded from a homepage via the Internet, for example. Further, the computer program for realizing the above-described embodiment may use an OS function already running on the computer. Further, a part of the computer program for realizing the above-described embodiment may be configured by firmware such as an expansion board attached to the computer, or may be executed by a CPU provided in the expansion board. Good.

Claims (15)

A display control device for controlling a display device having a light source means and a transmission means for transmitting light from the light source means,
Image acquisition means;
Control means for controlling the brightness of the light source means in the display device and the transmittance of the transmission means based on the image obtained by the image acquisition means;
The display control device, wherein the control unit sets a followability of a change in brightness of the light source unit with respect to a change in the image according to an operation mode of the display control device.   When the operation mode of the display device is a mode for displaying a moving image, the control unit is slower in following the change in the brightness of the light source unit than in a mode other than the mode for displaying the moving image. The display control apparatus according to claim 1, wherein:   When the operation mode of the display device is a mode for displaying a still image, the control unit can follow the change in brightness of the light source unit more than when the operation mode is a mode other than the mode for displaying the still image. The display control apparatus according to claim 1, wherein the display control device is set earlier. Reproducing means for reproducing a moving image or still image recorded on a recording medium,
When the control unit is in a mode for reproducing a moving image recorded on the recording medium, the control unit can follow the change in brightness of the light source unit more than in a mode for reproducing a still image recorded on the recording medium. The display control device according to claim 1, wherein the display control device is set late. Having imaging means;
When the control unit is in a mode for recording the image obtained by the imaging unit on a recording medium, the control unit is less likely to follow the change in brightness of the light source unit than in the mode for reproducing the still image. The display control apparatus according to claim 4, wherein the display control apparatus is set.   When the control unit is in a mode for reproducing a moving image recorded on the recording medium, the display unit displays the followability of a change in brightness of the light source unit with respect to a change in the image according to a reproduction operation of the moving image. The display control device according to claim 4, wherein the display control device is set according to an operation mode of the control device.   In the mode in which the moving image recorded on the recording medium is played back, the control means has brightness of the light source means when the playback state of the moving image is normal speed playback than when the normal speed playback is not performed. The display control apparatus according to claim 6, wherein the follow-up property of the change in the delay time is set late. A display control device for controlling a display device using a light source means and a transmission means,
Image acquisition means;
Based on the image obtained by the image acquisition means, the brightness of the light source means in the display device, and a control means for controlling the transmittance of the transmission means,
The display control apparatus, wherein the control means sets the followability of a change in brightness of the light source means with respect to a change in the image depending on whether or not the display control apparatus is in a state of displaying a moving image.   When the display device is in a state of displaying a moving image, the control unit sets the follow-up property of the brightness change of the light source unit to be slower than in a state of not displaying the moving image. The display control apparatus according to claim 8. A display control device for controlling a display device using a light source means and a transmission means,
Playback means for playing back a moving image recorded on a recording medium;
Control means for controlling the brightness of the light source means in the display device and the transmittance of the transmission means based on the image of each frame of the moving image reproduced by the reproduction means;
The display control apparatus, wherein the control means sets a followability of a change in brightness of the light source means with respect to a change in the image according to a reproduction state of the moving image.   The control means, when the playback state of the moving image is normal speed playback, sets slower follow-up of the brightness change of the light source means than when the normal speed playback is not performed. 10. The display control device according to 10.   The display control apparatus according to claim 1, wherein the display control apparatus includes the display apparatus. A control method of a display control device for controlling a display device using a light source means and a transmission means,
Based on the acquired image, when controlling the brightness of the light source means and the transmittance of the transmission means in the display device, the followability of the brightness change of the light source means with respect to the change of the image, A control method for a display control device, wherein the control method is set according to an operation mode of the display control device. A control method of a display control device for controlling a display device using a light source means and a transmission means,
Based on the acquired image, when controlling the brightness of the light source means in the display device and the transmittance of the transmission means, the followability of the change in the brightness of the light source means with respect to the change in the image, A control method for a display control device, wherein the display control device is set according to whether or not the display control device is in a state of displaying a moving image. A control method of a display control device for controlling a display device using a light source means and a transmission means,
The brightness of the light source means with respect to changes in the image when controlling the brightness of the light source means in the display device and the transmittance of the transmission means based on the image of each frame of the moving image reproduced from the recording medium. A control method for a display control apparatus, wherein the followability of the change of the video is set according to the reproduction state of the moving image.

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