JP5088166B2 - Image output characteristic correction system - Google Patents

Description

  The present invention relates to an image output characteristic correction system.

  A technique is known in which characteristics are adjusted for different display devices so as to achieve optimum display, respectively (see Patent Document 1).

JP 2006-13927 A

  In the prior art, it is necessary to install the display device so that the two face each other so that a display image by the display device is captured by the camera. However, it is desirable to adjust the characteristics more easily.

(1) An image output characteristic correction system according to the present invention includes a correction unit that corrects an image signal, a signal output unit that outputs a corrected image signal to an image output device, and an image output device based on the corrected image signal. An image pickup device for picking up an image output from the image pickup device, a display means for displaying an image picked up by the image pickup device, an image signal before correction by the correction means , and a correction means according to a comparison result of the image pickup signal from the image pickup device And determining means for determining the correction coefficient according to the above, and assist means for assisting framing so that an output image from the image output device is captured by the imaging device, and the image signal when the determining means determines the correction coefficient is: signal der to output adjustment image including a first indicator for positioning of position from the image output device to the central portion of the image is, the assist means causes the display means, to align the first index The corresponding second index for positioning for, superimposed on an image captured device is captured, and wherein the to be displayed on the central portion of the image.
(2) In the image output characteristic correction system according to the first aspect, the second index may have a frame shape so that the first index can be visually recognized at the center.
(3) In the image output characteristic correction system according to claim 1 or 2, the assist unit prompts the display unit to align the first index in the image captured by the image sensor with the position of the second index. A message may be displayed.
(4) In the image output characteristic correction system according to claim 1 or 2 , the assist means displays the first index in the adjustment image together with the adjustment image on the display means on the image output device. A message that prompts the user to match the position of the second index may be output.
(5) In the image output characteristic correction system according to any one of claims 1 to 4 , the assist unit may assist the image sensor so that a value corresponding to an elevation angle at which the image is captured falls within a predetermined range. it can.
(6) In the image output characteristic correction system according to ( 5 ), the assisting unit gives a message for assisting the display unit so that a value corresponding to an elevation angle at which the imaging element captures the image falls within a predetermined range. You may make it display on the said display means.
(7) In the image output characteristic correction system according to any one of claims 1 to 4, the assist means can assist the value corresponding to the magnification imaged by the image sensor to fall within a predetermined range.
(8) The image output characteristic correction system according to any one of claims 1 to 7 further determines the correction coefficient and determines the correction coefficient when the adjustment image is recognized from the image captured by the image sensor. You may provide the control means which controls a determination means and a correction means so that correction | amendment of an image signal may be started.
(9) In the image output characteristic correction system according to any one of claims 1 to 8, the image output device may be a display device, and in this case, the determining means displays from an image captured by the image sensor. It is also possible to acquire ambient light information reflected from the output surface of the apparatus and determine the gradation correction coefficient using this ambient light information.

  In the image output characteristic correction system according to the present invention, the output characteristic adjustment of the image output apparatus can be easily performed.

The best mode for carrying out the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram illustrating an image output characteristic correction system configured including an electronic camera 1 according to a first embodiment of the present invention. The image output characteristic correction system is configured by combining the electronic camera 1 and the image storage device 2. The display monitor 3 has a video display unit such as a liquid crystal display panel, a plasma display panel, a CRT, or a projection display. The display monitor 3 normally reproduces an image using a video signal supplied from the image storage device 2. User A appreciates the image displayed on the display monitor 3.

  When the user A views an image, the display characteristic of the display monitor 3 is corrected by the image output characteristic correction system. The display monitor 3 displays an image including an adjustment pattern transmitted from the electronic camera via the image storage device 2 when correcting the display characteristics. The electronic camera 1 captures a display screen by the display monitor 3 and calculates a correction value based on the captured image. The correction value is reflected in the video signal supplied from the image storage device 2 to the display monitor 3.

  The connection between the image storage device 2 and the display monitor 3 and between the image storage device 2 and the electronic camera 1 may be performed by wireless connection as shown in FIG. 1 or by wired connection using a cable.

<Electronic camera>
The electronic camera 1 is configured to be able to record captured image data in a recording medium 51 described later, and to transmit captured image data to an external device (for example, the image storage device 2).

  FIG. 2 is a block diagram illustrating a configuration example of the electronic camera 1. In FIG. 2, the electronic camera includes an imaging optical system 11, an imaging device 12, an AFE (Analog front end) circuit 13, an image processing unit 14, a buffer memory 15, an image output circuit 16, and a rear monitor 17. , RAM 18, ROM 19, CPU 20, recording interface (I / F) 21, communication interface (I / F) 22, and operation member 23.

  The CPU 20, RAM 18, ROM 19, recording interface 21, communication interface 22, image processing unit 14, buffer memory 15, image output circuit 16, and rear monitor 17 are connected via a bus 24.

  The imaging optical system 11 includes a plurality of lens groups including a zoom lens and a focusing lens, and forms a subject image on the light receiving surface of the imaging element 12. In order to simplify FIG. 1, the imaging optical system 11 is shown as a single lens.

  The image sensor 12 is configured by a CCD image sensor, a CMOS image sensor, or the like in which light receiving elements are two-dimensionally arranged on a light receiving surface. The image sensor 12 photoelectrically converts a subject image generated by a light beam that has passed through the imaging optical system 11 to generate an analog image signal. The analog image signal is input to the AFE circuit 13.

  The AFE circuit 13 performs correlated double sampling and gain adjustment on the analog image signal, and converts the analog-processed image signal into digital data. The digital image data is input to the image processing unit 14. The image processing unit 14 performs various types of image processing (color interpolation processing, gradation conversion processing, contour enhancement processing, white balance adjustment processing, image compression processing, image expansion processing, etc.) on the digital image data.

  The buffer memory 15 temporarily stores image data in the pre-process and post-process of image processing by the image processing unit 14. The image output circuit 16 generates a video signal to be sent to the external monitor 50. The image output circuit 16 can further perform a correction process on the video signal according to an instruction from the CPU 20. Transmission of the video signal to the external monitor 50 is performed from the image output circuit 16 via a cable.

  The rear monitor 17 is composed of a liquid crystal panel, and reproduces and displays images, operation menus, and the like according to instructions from the CPU 20. The RAM 18 is used as a work memory. The ROM 19 stores a program executed by the CPU 20 and stores test pattern data to be described later.

  The CPU 20 comprehensively controls operations performed by the electronic camera 1 by executing a program stored in the ROM 19. The CPU 20 also performs AF (autofocus) operation control and automatic exposure (AE) calculation. The AF operation uses, for example, a contrast detection method for obtaining a focus position of a focusing lens (not shown) based on contrast information of a through image. The through image refers to a monitor image acquired by the image sensor 12 before a shooting instruction.

  The recording interface 21 has a connector (not shown), and a recording medium 51 is connected to the connector. The recording interface 21 writes data to the connected recording medium 51 and reads data from the recording medium 51. The recording medium 51 is configured by a memory card with a built-in semiconductor memory, a hard disk drive, or the like.

  The communication interface 22 transmits / receives data to / from an external device in response to an instruction from the CPU 20. FIG. 1 illustrates a scene in which image data and correction information are transmitted to the image storage apparatus 2 that is an example of an external device by wireless communication via the communication interface 22.

  The operation member 23 includes a command dial, a cross key, an enter button, and the like. The operation member 23 sends an operation signal corresponding to each operation such as a mode switching operation and a menu selection operation to the CPU 21.

<Image storage device>
The image storage apparatus 2 in FIG. 1 supplies a video signal to the display monitor 3. The video signal supplied by the image storage device 2 is supplied to the image storage device 2 from image data stored in a hard disk drive (HDD) 24, which will be described later, or from an external device (for example, the electronic camera 1 or TV unner). Based on image data.

  FIG. 3 is a block diagram illustrating a configuration example of the image storage device 2. In FIG. 3, the image storage device 2 includes an image processing unit 14, a buffer memory 15, an image output circuit 16, a RAM 18, a ROM 19, a CPU 20, a recording interface (I / F) 21, and a communication interface (I / F) 22, an operation member 23, and a hard disk drive (HDD) 24.

  Among the configurations of the image storage device 2, the same components as those of the electronic camera 1 are denoted by the same reference numerals and description thereof is omitted. The hard disk drive 24 can store the image data file acquired via the communication interface 22 and can read the image data file stored in the drive.

  The video signal may be sent to the external monitor 50 (corresponding to the display monitor 3 in FIG. 1) from the image output circuit 16 via a cable, or by wireless communication via the communication interface 22. FIG. 1 illustrates a scene in which a video signal is transmitted to the display monitor 3 by wireless communication via the communication interface 22.

<Correction of display characteristics>
Processing for correcting the display characteristics of the display monitor 3 by the image output characteristic correction system configured by the electronic camera 1 and the image storage device 2 described above will be described with reference to the flowcharts of FIGS. FIG. 4 is a flowchart for explaining the flow of processing performed by the CPU 20 of the electronic camera 1 (hereinafter referred to as the electronic camera 1). For example, when communication is established with the image storage device 2, the electronic camera 1 activates the processing illustrated in FIG. 4.

<Processing on the electronic camera>
In step S <b> 101 of FIG. 4, the electronic camera 1 determines whether or not it is connected to the display monitor 3. When the electronic camera 1 receives a signal indicating that it is connected to the display monitor 3 from the image storage device 2, the electronic camera 1 makes an affirmative decision in step S101 and proceeds to step S102. If the electronic camera 1 does not receive a signal indicating that it is connected to the display monitor 3 from the image storage device 2, the electronic camera 1 makes a negative determination in step S101 and repeats the determination process.

  In step S102, for example, the electronic camera 1 displays a message screen “corrected / not corrected” on the rear monitor 17, proceeds to step S103, and waits for a selection operation by the user.

  In step S103, when an operation signal for selecting “correct” is issued from the operation member 23, the electronic camera 1 makes an affirmative determination in step S103 and proceeds to step S104. When the operation signal for selecting “correct” is not issued, the electronic camera 1 makes a negative determination in step S103 and ends the process of FIG.

  In step S104, the electronic camera 1 reads the adjustment pattern signal from the ROM 19, transmits the signal from the communication interface 22 to the image storage device 2, and proceeds to step S105. FIG. 5 is a diagram illustrating an adjustment pattern screen displayed on the display monitor 3 by the image storage apparatus 2 that has received the adjustment pattern. In FIG. 5, the adjustment pattern is configured by combining figures having different colors and densities. A positioning guide 55 is provided at the center of the pattern.

  In step S105, the electronic camera 1 causes the image sensor 12 to start imaging for a through image, and proceeds to step S106. Thereby, the electronic camera 1 starts to acquire a through image at a frame rate of 30 frames / second, for example.

  In step S106, the electronic camera 1 sends an instruction to the rear monitor 17 to start displaying the acquired through image. The electronic camera 1 further superimposes and displays the message 65 (for example, “Please enter ◎ on the TV screen here”) and the guide 66 on the through image, and the process proceeds to step S107. Accordingly, in the scene illustrated in FIG. 1, when the user A holds the electronic camera 1 so as to capture the adjustment pattern displayed on the display monitor 3, the electronic camera 1 displays the display screen (adjustment) of the display monitor 3. Image).

  FIG. 6 is a diagram illustrating an example of a screen displayed on the rear monitor 17 of the electronic camera 1. As illustrated in FIG. 6, the center guide 55 (FIG. 5) of the adjustment pattern displayed on the display monitor 3 is included in the guide 66 displayed on the rear monitor 17 of the electronic camera 1. When the user A holds the electronic camera 1, the electronic camera 1 displays a screen as illustrated in FIG. 7 on the rear monitor 17.

  In step S107 of FIG. 4, the electronic camera 1 determines whether or not the adjustment pattern can be recognized from the through image being captured. If the electronic camera 1 is recognizable, it makes a positive determination in step S107 and proceeds to step S108. If it cannot be recognized, the electronic camera 1 makes a negative determination in step S107 and repeats the determination process. Recognition may be determined by whether or not individual figures constituting the adjustment pattern can be separated and identified.

  In step S108, the electronic camera 1 determines whether the elevation angle in the through image being captured is within a predetermined range. In general, since the size of a subject to be imaged is inversely proportional to the distance from the electronic camera 1, the subject that is farther from the electronic camera 1 appears smaller. For this reason, when the display screen of the display monitor 3 is imaged from an oblique direction rather than from the front, the adjustment pattern in the through image is imaged large on the near side and small on the opposite side (see FIG. 8). Therefore, the electronic camera 1 determines whether or not the elevation angle is possible using the ratio of the lengths h1 and h2 (FIG. 9) of the left and right sides constituting the adjustment pattern.

  If the ratio of h1 and h2 is within the predetermined range, the electronic camera 1 makes an affirmative determination in step S108 and proceeds to step S109. If the ratio of h1 and h2 is not within the predetermined range, the electronic camera 1 makes a negative determination in step S108 and proceeds to step S111. move on.

  In step S111, the electronic camera 1 superimposes and displays a message (for example, “Please take a picture from the front of the television screen”) over the through image being displayed on the rear monitor 17, and then returns to step S107. As a result, the user A can be prompted to take the adjustment pattern displayed on the display monitor 3 from the front of the display monitor 3.

  In step S109, the electronic camera 1 determines whether or not the size of the adjustment pattern in the through image being captured is within a predetermined range. If the adjustment pattern in the through image is too large, the adjustment pattern is deviated from the through image, and if the adjustment pattern in the through image is too small, it is difficult to recognize the adjustment pattern from the through image. Therefore, the electronic camera 1 has a predetermined length h1 or h2 of the left and right sides (or upper and lower sides) constituting the adjustment pattern in the through image with respect to the length of the corresponding side of the through image. If it falls within the ratio (for example, 50 to 90%), an affirmative decision is made in step S109 and the process proceeds to step S112. If the length h1 or h2 does not fall within the predetermined ratio with respect to the corresponding side length of the through image, the electronic camera 1 makes a negative determination in step S109 and proceeds to step S110.

  In step S110, the electronic camera 1 drives the zoom lens (not shown) to move back and forth in the optical axis direction, thereby changing the magnification of the captured through image, and returns to step S109. Thereby, the magnification of the through image displayed on the rear monitor 17 is changed, and the size of the adjustment pattern in the through image is changed.

  In step S112, the electronic camera 1 acquires adjustment pattern information from the through image, and proceeds to step S113. Specifically, data corresponding to the adjustment pattern is extracted from the data of the through image. In step S113, the electronic camera 1 determines whether correction is necessary. The electronic camera 1 compares the adjustment pattern data transmitted to the image storage apparatus 2 in step S104 with the adjustment pattern data extracted in step S113. The electronic camera 1 compares the color component ratios (for example, RGB signal ratios) and signal values of the data constituting the corresponding figure (rectangle in this example) between the data of both adjustment patterns, and the difference between these is predetermined. It is determined whether or not the determination threshold is exceeded.

  The electronic camera 1 makes an affirmative determination in step S113 and proceeds to step S114 when the difference between the signal values constituting the graphic exceeds the determination threshold for at least one of the corresponding graphics. The electronic camera 1 makes a negative determination in step S113 when the difference between the signal values is equal to or less than the determination threshold in all of the corresponding graphics, and ends the process of FIG. The negative determination in step S113 is a case where it is determined that the display characteristics of the display monitor 3 need not be corrected.

  In step S114, the electronic camera 1 that has determined that it is necessary to correct the display characteristics of the display monitor 3 calculates a correction coefficient so as to reduce the difference between the signal values constituting the corresponding graphic, and proceeds to step S115. As the correction coefficient, a common value is calculated over the entire area of the image.

(Color correction)
For example, the correction coefficient for the R signal is a common value for the entire image based on the color component ratio of the data constituting all the corresponding figures. Similarly, with respect to the correction coefficients for the G signal and B signal, a common value is obtained for the entire image area based on the color component ratio of the data constituting all the corresponding figures.

(Gradation correction)
The luminance correction coefficient is obtained as follows. FIG. 10 is a diagram illustrating the gradation characteristics of the display monitor 3. The horizontal axis represents the input signal, and the vertical axis represents the output signal. Usually, the brightness of the screen by the display monitor 3 includes a reflected light component of ambient light (for example, indoor illumination light) unless the environment is completely dark. Therefore, the luminance characteristics of the display screen by the display monitor 3 in the through image acquired by the electronic camera 1 change depending on the reflected light component.

  FIG. 11 is a diagram illustrating screen brightness by the display monitor 3. The horizontal axis represents the input signal, and the vertical axis represents the screen brightness. As illustrated in FIG. 11, even when the input signal is 0, the screen luminance varies depending on the reflected light component of the ambient light. Therefore, the electronic camera 1 changes the gradation characteristic curve according to the screen luminance corresponding to the input signal of 0.

  FIG. 12 is a diagram for explaining gradation characteristic curve correction according to the present embodiment. When the screen reflection of ambient light is small and the screen brightness is low, the electronic camera 1 corrects the gradation characteristic curve so that a dark signal is displayed darker than usual. On the contrary, when the screen reflection of the ambient light is large and the screen brightness is high, the gradation characteristic curve is corrected so that a dark signal is displayed brighter than usual.

  The ambient light reflection component (that is, the screen luminance corresponding to an input signal of 0) is the darkest part of the figure constituting the adjustment pattern in the through image (in this example, the figure Bs located at the lower left in FIG. 5). ) Is acquired using the signal value included in.

  In step S115 of FIG. 4, the electronic camera 1 transmits data (correction value information) indicating the calculated correction coefficient to the image storage device 2 and returns to step S112.

<Processing of image storage device>
FIG. 13 is a flowchart for explaining the flow of processing performed by the CPU 20 of the image storage device 2 (hereinafter referred to as the image storage device 2). For example, when communication is established with the electronic camera 1, the image storage device 2 activates the processing illustrated in FIG.

  In step S <b> 201 of FIG. 13, the image storage apparatus 2 determines whether or not it is connected to the display monitor 3. When communication with the display monitor 3 is established, the image storage device 2 makes a positive determination in step S201 and proceeds to step S202. If communication with the display monitor 3 is not established, the image storage apparatus 2 makes a negative determination in step S201 and repeats the determination process.

  In step S202, the image storage apparatus 2 transmits a signal indicating that it is connected to the display monitor 3 to the electronic camera 1, and proceeds to step S203. In step S <b> 203, the image storage device 2 determines whether image data has been received from the electronic camera 1. If the image storage apparatus 2 has received the image data, the determination in step S203 is affirmative and the process proceeds to step S204. If the image data is not received, the determination in step S203 is negative and the process proceeds to step S208.

  In step S <b> 204, the image storage device 2 uses the received image data (in this example, adjustment pattern data) to generate a video signal necessary for playback display on the display monitor 3, and the video is output to the display monitor 3. The transmission of the signal is started and the process proceeds to step S205. Here, the image storage device 2 superimposes a message (for example, “Please point the camera at this point so that the ◎ of the screen is placed on the ○ of the camera monitor”) on the playback image displayed on the display monitor 3. Message information is included in the video signal for display.

  In step SS205, the image storage device 2 determines whether correction information has been received from the electronic camera 1. If the correction value information is received, the image storage apparatus 2 makes a positive determination in step S205 and proceeds to step S206. If the correction value information is not received, the image storage apparatus 2 makes a negative determination in step S205 and proceeds to step S208.

  In step S <b> 206, the image storage device 2 corrects the video signal transmitted to the display monitor 3. Specifically, using the correction value information, the image data (adjustment pattern data) received in step S203 is corrected in order of pixels. For example, each of the R component data of the adjustment pattern data is multiplied by the correction coefficient of the R signal included in the correction value information. The same applies to the other color components. For the gradation correction coefficient, the correction coefficient included in the correction value information is multiplied according to the signal value of the adjustment pattern data. When the image storage apparatus 2 performs the correction process as described above, the process proceeds to step S207.

  In step S207, the image storage apparatus 2 stores the latest correction value information and returns to step S205. The image storage apparatus 2 is configured to perform correction using the stored correction value information on the video signal transmitted to the display monitor 3 until new correction information is received thereafter. That is, after the correction of the display characteristics of the display monitor 3 is completed, an image based on the image data acquired by the image storage apparatus 2 via the communication interface 22 or the image data stored in the hard disk drive 24 is reproduced on the display monitor 3. Even in the case of display, correction using the stored correction value information is performed.

  In step S208, the image storage apparatus 2 determines whether or not a timeout has occurred. When the image storage device 2 measures a predetermined time (for example, 20 seconds), the determination in step 208 is affirmative, and the processing in FIG. 13 is terminated. The image storage apparatus 2 makes a negative determination in step 208 and returns to step S203 before measuring a predetermined time (for example, 20 seconds).

According to the first embodiment described above, the following operational effects can be obtained.
(1) Since the positioning guide 55 is included in the adjustment pattern (FIG. 5) displayed on the display monitor 3 when the display output characteristic is corrected by the display monitor 3 (FIG. 5), the user A displays it on the electronic camera 1 It becomes a mark for framing aiming at the output surface (screen) of the monitor 3. This makes it possible to correct the display characteristics of the display monitor 3 while holding the electronic camera 1 without using a tripod or the like.

(2) When the through image obtained by the electronic camera 1 capturing the output surface (screen) of the display monitor 3 is displayed on the rear monitor 17 of the electronic camera 1, the positioning guide 66 is displayed over the through image (see FIG. 6) The user A becomes a mark for framing with the electronic camera 1 aiming at the output surface (screen) of the display monitor 3. This makes it possible to correct the display characteristics of the display monitor 3 while holding the electronic camera 1 without using a tripod or the like.

(3) Since the electronic camera 1 automatically changes the magnification of the through image captured by driving a zoom lens (not shown) forward and backward in the optical axis direction (step S110), the recognition of the adjustment pattern is simple. The display screen by the display monitor 3 can be imaged at a magnification suitable for the display.

(4) The electronic camera 1 determines the elevation angle using the ratio of the lengths h1 and h2 (FIG. 9) of the left and right sides constituting the adjustment pattern (step S108), and sends a message according to the determination result. Therefore, the user A can be prompted to take the adjustment pattern displayed on the display monitor 3 from the front of the display monitor 3 with the electronic camera 1 (step S111).

(5) The electronic camera 1 proceeds to the correction process when the adjustment pattern information is recognized from the through image. If it is not recognized, the process does not proceed to the correction process, so that inappropriate correction can be prevented.

(6) The electronic camera 1 proceeds to the correction process when the values indicating the magnification and the elevation angle are appropriate. Since the process does not proceed to the correction process if it is inappropriate, the user A can know whether or not the imaging necessary for the correction has been performed by whether or not the electronic camera 1 proceeds to the correction process.

(7) The electronic camera 1 (a) corrects the gradation characteristic curve so that a dark signal is displayed darker than normal when the ambient light reflection is small on the screen of the display monitor 3 and the screen brightness is low, ( b) When the screen of the display monitor 3 has a large reflection of ambient light and the screen brightness is high, the gradation characteristic curve is corrected so that a dark signal is displayed brighter than usual. Since the ambient light is not directly measured but the correction is performed by using the reflected light from the screen of the display monitor 3 (imaging), an effect is obtained in that the dark area of the image is naturally expressed.

(8) Since the dark part (figure Bs) is included in the adjustment pattern, the electronic camera 1 captures the screen of the display monitor 3 displaying the adjustment pattern, and the ambient light reflection component (the input signal becomes 0). (Corresponding screen brightness) can be easily acquired and used for the correction of (7) above.

(Second embodiment)
In the second embodiment, at the time of correcting the display characteristics of the display monitor 3, the electronic camera 1 transmits adjustment pattern information obtained by photographing the display screen of the display monitor 3 to the image storage device 2. The image storage device 2 calculates a correction value based on the adjustment pattern information, and reflects the calculated correction value in the video signal supplied to the display monitor 3.

  A process in which the image output characteristic correction system according to the second embodiment corrects the display characteristics of the display monitor 3 will be described with reference to the flowcharts of FIGS. FIG. 14 is a flowchart for explaining the flow of processing performed by the CPU 20 of the electronic camera 1 (hereinafter referred to as the electronic camera 1). The electronic camera 1 activates the process of FIG. 14 instead of the process of FIG.

<Processing on the electronic camera>
In FIG. 14, when the same processing as in FIG. 4 is performed, the same step number is assigned and the description is omitted. The difference between FIG. 4 and FIG. 14 is that step S113B is provided instead of the processing of steps S113 to S115 in FIG.

  In step S113B following step S112, the electronic camera 1 transmits the adjustment pattern information acquired from the through image to the image storage device 2 and returns to step S112.

<Processing on the image storage device side>
In FIG. 15, when the same processing as in FIG. 13 is performed, the same step number is assigned and description thereof is omitted. The difference between FIG. 13 and FIG. 15 is that steps S210 to S212 are provided instead of the process of step S205 of FIG.

  In step S <b> 210 that follows step S <b> 204, the image storage device 2 determines whether or not adjustment pattern information has been received from the electronic camera 1. The image storage apparatus 2 makes a positive determination in step S210 when the adjustment pattern information is received and proceeds to step S211. If not received, the image storage apparatus 2 makes a negative determination in step S210 and proceeds to step S208.

  In step S211, the image storage apparatus 2 determines whether correction is necessary. The image storage device 2 compares the adjustment pattern data received from the electronic camera 1 in step S203 with the adjustment pattern information received in step S210, and the electronic storage device 1 according to the first embodiment (step 113). The determination is performed in the same manner.

  In step S212, the image storage apparatus 2 that has determined that the display characteristics of the display monitor 3 need to be corrected calculates the correction coefficient in the same manner as the electronic camera 1 (step 114) according to the first embodiment, and proceeds to step S206. Step S206 and subsequent steps are the same as in the first embodiment. That is, the image storage device 2 corrects the video signal to be transmitted to the display monitor 3 thereafter with the correction coefficient.

According to the second embodiment described above, the following functions and effects can be obtained in addition to the functions and effects of the first embodiment.
(1) Since the image storage apparatus 2 calculates the correction value based on the adjustment pattern information, the trouble of calculating the correction value in the electronic camera 1 can be saved.

(2) Since the correction value calculated by the image storage device 2 can be immediately reflected in the video signal supplied from the image storage device 2 to the display monitor 3, it can be quickly followed even when the ambient light changes.

(Third embodiment)
In the third embodiment, the adjustment pattern information is stored in the image storage device 2, and when the display characteristics of the display monitor 3 are corrected, the adjustment pattern information is transmitted from the image storage device 2 to the display monitor 3. An image including the adjustment pattern is displayed. The electronic camera 1 transmits adjustment pattern information obtained by photographing the display screen by the display monitor 3 to the image storage device 2. The image storage device 2 calculates a correction value based on the adjustment pattern information, and reflects the calculated correction value in the video signal supplied to the display monitor 3.

  A process in which the image output characteristic correction system according to the third embodiment corrects the display characteristics of the display monitor 3 will be described with reference to the flowcharts of FIGS. FIG. 16 is a flowchart for explaining the flow of processing performed by the CPU 20 of the electronic camera 1 (hereinafter referred to as the electronic camera 1). The electronic camera 1 activates the process of FIG. 16 instead of the process of FIG.

<Processing on the electronic camera>
In FIG. 16, when the same processing as in FIG. 14 is performed, the same step number is assigned and the description is omitted. The difference between FIG. 14 and FIG. 16 is that the process of step S104 of FIG. 14 is skipped. Since the adjustment pattern information is stored in the image storage device 2, there is no need to transmit it from the electronic camera 1 to the image storage device 2.

<Processing on the image storage device side>
In FIG. 17, when the same processing as in FIG. 15 is performed, the same step number is assigned and description thereof is omitted. The difference between FIG. 15 and FIG. 17 is that step S203 in FIG. 15 is skipped, and step S204B is provided instead of step S204.

  In step S204B following step S202, the image storage apparatus 2 reads out the adjustment pattern signal from the ROM 19, generates a video signal necessary for reproduction display on the display monitor 3 using the signal data, and displays the display monitor 3 on the display monitor 3. Then, transmission of the video signal is started and the process proceeds to step S210. Here, the image storage device 2 superimposes a message (for example, “Please point the camera at this point so that the ◎ of the screen is placed on the ○ of the camera monitor”) on the playback image displayed on the display monitor 3. Message information is included in the video signal for display. The subsequent steps are the same as in the second embodiment.

According to the third embodiment described above, the following operational effects can be obtained in addition to the operational effects of the first embodiment.
(1) Since the image storage device 2 stores the adjustment pattern signal, the adjustment pattern signal is transmitted from the electronic camera 1 to the image storage device 2 as compared with the first embodiment and the second embodiment. This saves you time and effort.

(2) Since the image storage device calculates the correction value based on the adjustment pattern information, the trouble of calculating the correction value in the electronic camera 1 can be saved.

(3) Since the correction value calculated by the image storage device 2 can be immediately reflected in the video signal supplied from the image storage device 2 to the display monitor 3, it can be quickly followed even when the ambient light changes.

(Modification 1)
In the above description, the display monitor 3 has been described as an example of the image output device. As another example of the image output apparatus, the present invention can be applied to a printer. In this case, the electronic camera 1 captures an image of a printing surface (an adjustment pattern is printed) printed by the printer. When the image storage device 2 transmits the corrected video signal to the printer, the printer changes the tone characteristics indicating the relationship between the ink color component ratio and the input signal and the amount of ink to be ejected, thereby correcting the printing characteristics.

(Modification 2)
You may comprise so that step S102 and step S103 in a flowchart may be skipped. In this case, when communication between the electronic camera 1 and the image storage device 2 is established, the process proceeds to step S104, so that the adjustment pattern screen (FIG. 5) is displayed on the display monitor 3 immediately after the communication is established.

(Modification 3)
The electronic camera 1 and the image storage device 2 constitute an image output characteristic correction system. However, the electronic output characteristics of the display monitor 3 may be corrected by an electronic camera in which the electronic camera 1 and the image storage apparatus 2 are integrated. Absent.

  The above description is merely an example, and is not limited to the configuration of the above embodiment.

It is a figure which illustrates the image output characteristic correction system by a first embodiment of the present invention. It is a block diagram explaining the structural example of an electronic camera. It is a block diagram explaining the structural example of an image storage apparatus. It is a flowchart explaining the flow of the process which an electronic camera performs. It is a figure which illustrates the pattern screen for adjustment. It is a figure which shows an example of the screen displayed on the back monitor of an electronic camera. It is a figure which shows an example of the screen displayed on the back monitor of an electronic camera. It is a figure which shows an example of the screen displayed on the back monitor of an electronic camera. It is a figure explaining determination of the propriety of an elevation angle. It is a figure which illustrates the gradation characteristic of a display monitor. It is a figure which illustrates the screen brightness | luminance by a display monitor. It is a figure explaining gradation characteristic curve correction. It is a flowchart explaining the flow of the process which an image storage apparatus performs. It is a flowchart explaining the flow of the process which the electronic camera of 2nd embodiment performs. It is a flowchart explaining the flow of the process which the image storage apparatus of 2nd embodiment performs. It is a flowchart explaining the flow of the process which the electronic camera of 3rd embodiment performs. 14 is a flowchart illustrating a flow of processing performed by the image storage apparatus according to the third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electronic camera 2 ... Image storage apparatus 3 ... Display monitor 12 ... Image pick-up element 16 ... Image output circuit 17 ... Back monitor 20 ... CPU
22. Communication interface 55, 66 ... Guide

Claims (9)

Correction means for correcting the image signal;
Signal output means for outputting the corrected image signal to an image output device;
An image sensor that captures an image output by the image output device based on the corrected image signal;
Display means for displaying an image captured by the image sensor;
A determination unit that determines a correction coefficient by the correction unit according to a comparison result between an image signal before correction by the correction unit and an image signal from the image sensor;
Assist means for assisting framing so that an output image from the image output device is captured by the image sensor,
Said image signal when said determining means determines a correction coefficient, Ri signal der to output adjustment image including a first indicator for positioning at the center portion of the image from said image output apparatus,
The assist means causes the display means to display a corresponding second index for positioning for aligning the first index on the image captured by the imaging element and display it on the center of the image. An image output characteristic correction system characterized by this. The image output characteristic correction system according to claim 1,
2. The image output characteristic correction system according to claim 1, wherein the second index has a frame shape so that the first index can be visually recognized at a central portion thereof . The image output characteristic correction system according to claim 1 or 2,
The assist means causes the display means to display a message that prompts the first index in the image captured by the image sensor to be aligned with the position of the second index . The image output characteristic correction system according to claim 1 or 2 ,
The assist means causes the image output device to output a message that prompts the first index in the adjustment image to be aligned with the position of the second index displayed on the display means together with the adjustment image. A characteristic image output characteristic correction system. In the image output characteristic correction system according to any one of claims 1 to 4,
The image output characteristic correction system according to claim 1, wherein the assist unit assists a value corresponding to an elevation angle at which the image sensor captures the image to fall within a predetermined range . The image output characteristic correction system according to claim 5 ,
The assist means causes the display means to display a message for assisting so that a value corresponding to an elevation angle at which the image pickup device picks up the image falls within a predetermined range . In the image output characteristic correction system according to any one of claims 1 to 4,
The image output characteristic correction system according to claim 1, wherein the assist means assists a value corresponding to a magnification taken by the image sensor to fall within a predetermined range. In the image output characteristic correction system according to any one of claims 1 to 7,
When the adjustment image is recognized from an image captured by the image sensor, the determination unit and the correction unit are controlled to start the correction coefficient determination and the correction of the image signal by the determined correction coefficient. An image output characteristic correction system further comprising control means. In the image output characteristic correction system according to any one of claims 1 to 8,
The image output device is a display device;
The determining means obtains ambient light information reflected from the output surface of the display device from an image captured by the image sensor, and determines a gradation correction coefficient using the ambient light information. Characteristic correction system.

Images