JP2012165474A - Imaging apparatus, control method of the same, program and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide technology for switching an image processed by adapting it to a color gamut different from that of a recording image at arbitrary timing and displaying the image on an image display section without affecting the image in the middle of recording.SOLUTION: An imaging apparatus includes: imaging means imaging a subject; a camera signal processing section processing image data outputted from the imaging means to be adapted to a plurality of color gamuts; first selecting means selecting image data corresponding to a first color gamut from the image data processed by the camera signal processing section; second selecting means selecting image data corresponding to a second color gamut from the image data processed by the camera signal processing section; an image recording section recording the image data selected by the first selecting means; and an image display section displaying the image data selected by the second selecting means. Even if the image recording section records the image data, the first selecting means and the second selecting means can select the color gamut of the recording image to the image recording section and the color gamut of a display image to the image display section.

Description

  The present invention relates to an imaging apparatus that displays and records captured images.

  A plurality of color gamuts are defined in the RGB color gamut relating to color images, but in recent imaging apparatuses, products corresponding to a wider color gamut have been put into practical use. For example, an imaging apparatus such as a digital camera that captures a still image has so far mainly used a color gamut called sRGB. Also, in a display that displays a captured still image, the color gamut that can be displayed is mainly sRGB. However, recently, many digital cameras and displays capable of performing image processing corresponding to a color gamut called AdobeRGB having a color gamut wider than sRGB have been commercialized.

  On the other hand, with regard to a television camera for shooting a moving image, ITU-R BT. A color gamut equivalent to sRGB defined in 709 (hereinafter referred to as BT.709) has been used. However, recently, BT. A color gamut wider than 709 has been proposed, and it is an international standard as Non-Patent Document 1 from the IEC (International Electrotechnical Commission).

  The color gamut defined by this standard is called an xvYCC (moving color extended color space) color gamut, and imaging devices and display devices corresponding to this standard have been developed.

  Note that there is Patent Literature 1 as a proposal related to an imaging device and a display device using the xvYCC color gamut.

  Thus, with regard to display devices for television and computer displays, display devices capable of displaying only the sRGB color gamut and the AdobeRGB color gamut and the xvYCC color gamut have been put into practical use.

  In addition, while a plurality of different color gamuts are defined as described above, an image pick-up device typified by a digital camera allows a user to select one of the color gamuts as necessary to display an image. Products that can process and record data that matches the selected color gamut have also been put into practical use. Patent Documents 2 and 3 are conventional techniques of such an imaging apparatus.

  FIG. 14 shows a configuration of a conventional imaging device capable of selecting a plurality of color gamuts.

  In FIG. 14, an optical image from a subject is formed on a CCD 1402 via a lens 1401 and subjected to photoelectric conversion.

  The signal photoelectrically converted by the CCD 1402 is subjected to known gamma processing, color matrix processing, and the like by a camera signal processing unit 1403 and is output as camera image data.

  Camera image data output from the camera signal processing unit 1403 is input to an image recording unit 1404 and an image display unit (finder) 1405 for image confirmation.

  The image recording unit 1404 performs image compression processing such as JPEG or MPEG2 on the camera image data, and records the data on a recording medium 1406 such as a magnetic tape or a memory card.

  An operation unit 1407 performs various operations of the entire imaging apparatus such as recording start / stop and designation of a color gamut to be recorded.

  Reference numeral 1408 denotes a system controller that performs overall control of the entire imaging apparatus. A memory 1409 stores a control program of the system controller 1408, matrix coefficients corresponding to a plurality of color gamuts, and the like.

  Here, the operation of changing the color gamut of the image recorded by the user will be briefly described.

  The user operates the operation unit 1407 to specify a color gamut to be recorded from a plurality of color gamuts. Next, the system controller 1408 reads the color matrix coefficient corresponding to the selected color gamut from the memory 1409 and outputs it to the camera signal processing unit 1403.

  The camera signal processing unit 1403 performs color matrix processing according to the input color matrix coefficient, and generates image data corresponding to the designated color gamut.

  As a result, camera image data processed in the color gamut designated by the user is output to the image recording unit 1404 and the image display unit 1405.

  In addition, when reproducing an image, there is a configuration that can adjust the saturation when the image is displayed on the image display unit 1405 according to the color gamut of the recorded image.

JP 2006-033575 A JP 2004-096400 A JP 2005-292814 A

IEC 61966-2-4

  In Patent Documents 2 and 3, for example, when the user wants to switch and display an image processed in a plurality of color gamuts on the image display unit 1405 while recording an image, the color gamut processed by the camera signal processing unit 1403 is changed. It is necessary to switch.

  However, if the user performs an operation to change the color gamut processed by the camera signal processing unit 1403 while images are being continuously recorded, the image data recorded on the recording medium 1406 is also displayed in the middle of the continuous image. The area changes and the color changes in the middle of the scene. Therefore, when an image processed with a color gamut different from the recorded image is desired to be visually recognized on the image display unit 1405 while the image is being recorded, the recording operation is temporarily stopped and the image with the color gamut switched by the image display unit 1405 is visually recognized. Therefore, it becomes a complicated work to start recording an image again.

  Thus, conventionally, it is difficult to visually recognize an image processed in a color gamut different from the image being recorded on the image display unit 1405 without affecting the color of the recorded image during image recording. .

  The present invention has been made in view of the above problems, and can switch and display an image processed in a color gamut different from the color gamut of the recorded image without affecting the image being recorded. Realize technology.

  In order to solve the above-described problems, an imaging apparatus according to the present invention includes an imaging unit that images a subject, a camera signal processing unit that performs processing for adapting image data output from the imaging unit to a plurality of color gamuts, First selection means for selecting image data corresponding to the first color gamut from the image data processed by the camera signal processing unit, and corresponding to the second color gamut from the image data processed by the camera signal processing unit A second selection unit for selecting image data; an image recording unit for recording the image data selected by the first selection unit; an image display unit for displaying the image data selected by the second selection unit; Even when the image recording unit records image data, the color gamut of the recorded image on the image recording unit and the color of the display image on the image display unit by the first selection unit and the second selection unit You can select the door.

  According to the present invention, an image having a color gamut different from the recorded image can be displayed on the image display unit without changing the color gamut of the recorded image even during image recording. Therefore, it is possible to switch and display images when processing in a plurality of color gamuts in the image display unit without affecting the color of the recorded image.

It is a block diagram which shows the structure of the video camera of embodiment which concerns on this invention. It is a block diagram which shows the structure of a 1st color gamut signal processing part. BT. 709 and 709 are diagrams illustrating the color gamut of the image sensor. It is a figure which shows the gamma characteristic of xvYCC. It is a figure which shows the relationship which converts a luminance signal into a digital value. It is a figure which shows the relationship which converts a color difference signal into a digital value. BT. It is a figure which shows the range which the signal of 709 and xvYCC can take. It is a block diagram which shows the structure of a 2nd color gamut signal processing part. BT. 7 is a diagram illustrating color gamut compression to 709. FIG. It is a figure which shows the example of a gain correction table storage in memory. It is a figure which shows the menu screen at the time of color gamut selection. It is a figure which shows the example of a display of color gamut information. It is a block diagram which shows the other structure of a 2nd color gamut signal processing part. It is a block diagram which shows the structure of the conventional imaging device.

  Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings.

  The embodiment described below is an example as means for realizing the present invention, and should be appropriately modified or changed according to the configuration of the apparatus to which the present invention is applied and various conditions. It is not limited to the embodiment.

  FIG. 1 is a block diagram showing a configuration of a video camera to which the present invention can be applied.

  In the following description, for the camera signal processing unit that performs processing corresponding to a plurality of color gamuts, the types of the color gamuts to be processed are described in the above-described xvYCC and BT. 709 will be described as two types.

  In FIG. 1, 101 is a lens, 102 is an image sensor such as a CCD, and 103 is a camera signal processing unit that performs processing corresponding to two types of color gamuts.

  Reference numeral 104 denotes a first selection unit that selects one of the image signals processed corresponding to the two types of color gamut for the image display unit 106.

  Reference numeral 105 denotes a second selection unit that selects one of the image signals processed corresponding to the two types of color gamut for the image recording unit 107.

  Reference numeral 106 denotes an image display unit that displays an image, 107 denotes an image recording unit that performs processing such as image compression related to recording of image data, and 108 denotes a storage medium configured by a magnetic tape, nonvolatile memory, or the like on which image data is recorded. It is.

  Reference numeral 109 denotes a system controller that performs overall control of the entire video camera.

  Reference numeral 110 denotes an operation unit that receives an operation by a user, and 111 denotes a memory that stores a program of the system controller 109, a gain correction table described later, and the like.

  Next, the operation of each block shown in FIG. 1 will be described.

  First, an optical image from a subject is adjusted on zoom, focus, and aperture by a lens 101 and formed on the image sensor 102. The image sensor 102 generates R, G, and B signals corresponding to the optical image of the subject.

  Note that the image sensor 102 in this embodiment is a BT. Suppose that it has characteristics corresponding to a color gamut wider than the primary color points of R, G, and B defined in 709.

  Here, BT. The primary color point 709 and the primary color point of the image sensor of the present embodiment will be described with reference to FIG.

  FIG. 3 is a general xy chromaticity diagram. In the figure, the area inside the triangle indicated by 301 is BT. Gamut range defined by R, G, and B primary color points defined in 709.

  A region inside the triangle indicated by 302 is a color gamut range constituted by R, G, and B primary color points of the image sensor 102. The range inside 303 is the entire range of visible light that can be recognized by humans.

  In this embodiment, BT. R, G, and B signals output from an image sensor that can handle a color gamut wider than 709 are input to the camera signal processing unit 103.

  The camera signal processing unit 103 includes a first color gamut signal processing unit 103-1 and a second color gamut signal processing unit 103-2, and a signal output from the first color gamut signal processing unit 103-1 is the second. Input to the color gamut signal processing unit 103-2.

  A signal output from the image sensor 102 described above is first input to a first color gamut signal processing unit 103-1 in the camera signal processing unit 103.

  Here, the configuration and operation of the first color gamut signal processing unit 103-1 will be described.

  FIG. 2 is a block diagram illustrating a configuration of the first color gamut signal processing unit.

  Note that the processing method of the first signal processing unit in this embodiment is BT. 709 is a processing method for a signal having a color gamut wider than the primary color points of R, G, and B defined in 709, and details thereof are described in Non-Patent Document 1 and Patent Document 1 described above. Only the outline of will be described.

  In FIG. 2, reference numeral 201 denotes a linear matrix processing unit that performs 3 × 3 linear matrix processing on R, G, and B signals output from the image sensor 102, and performs BT. 709 is converted into R_ex, G_ex, and B_ex signals.

  In this linear matrix processing, the input primary color points of the image sensor 102 are BT. When the signal is in the vicinity of the primary color point defined in 709, the output R_ex, G_ex, and B_ex signals change between 0 and 1.

  However, as shown by 302 in FIG. When it is wider than the primary color point defined in 709, the output R_ex, G_ex, and B_ex signals may be negative and greater than 1.

  The R_ex, G_ex, and B_ex signals subjected to linear matrix processing in this way are then input to the gamma processing unit 202 of 202. The input / output characteristics of the gamma processing performed by the gamma processing unit 202 are shown in FIG.

  As described above, the R_ex, G_ex, and B_ex signals input to the gamma processing unit 202 may be negative and larger than 1 in addition to 0 or more and 1 or less.

  Therefore, when the input is 0 or more and 1 or less, BT. The gamma characteristic defined in 709 is taken, and when the input is negative and larger than 1, it is an extended characteristic.

  The R_ex_g, G_ex_g, and B_ex_g signals that have been gamma processed with the characteristics shown in FIG. 4 are input to the YC matrix processing unit 203.

  In the YC matrix processing unit 203, the BT. A process of converting R_ex_g, G_ex_g, and B_ex_g into a luminance signal Y_ex and color difference signals Cr_ex and Cb_ex by the 3 × 3 matrix equation defined in 709 is performed.

  Next, the 8-bit digital value (0 to 255) is assigned to the luminance signal Y_ex obtained by the above equation as shown in FIG. For example, when the signal level of Y_ex obtained by the above equation is 0, it is assigned to 16 digital values, and when the signal level is 1.0, it is assigned to 235 digital values.

  Further, the signals of the color difference signals Cr_ex and Cb_ex are assigned with 8-bit values (0 to 255) as shown in FIG. For example, when the signal level of Cr_ex or Cb_ex obtained by the above equation is −0.5, it is assigned to 16 digital values, and when the signal level is +0.5, it is assigned to 240 digital values.

  FIG. 7 shows a range of values that can be taken by the luminance signal Y_ex and the color difference signals Cr_ex and Cb_ex signals assigned to these digital values.

  In the figure, a region surrounded by a rectangle 701 is a range of values that the luminance signal Y_ex and the color difference signals Cr_ex and Cb_ex can take.

  In the figure, the hatched area 702 is a range that can be taken when R_ex, G_ex, and B_ex are 0 or more and 1 or less. 709 corresponds to the color gamut.

  That is, in FIG. 7, the region outside the region 702 is a region that can be taken when any of R_ex, G_ex, and B_ex is negative or larger than 1.

  The luminance signal Y_ex and the color difference signals Cr_ex and Cb_ex processed by the first color gamut signal processing unit 103-1 are output from the terminal 103 a of the camera signal processing unit 103, and the terminal 104 a and the second selection unit 105 of the first selection unit 104. Are respectively input to the terminals 105a.

  On the other hand, the signal processed by the first color gamut signal processing unit 103-1 is input to the second color gamut signal processing unit 103-2 in the camera signal processing unit 103.

  In the present embodiment, an example in which the luminance signal Y_ex and the color difference signals Cr_ex and Cb_ex processed by the first color gamut signal processing unit 103-1 are input to the second color gamut signal processing unit 103-2 will be described.

  The second color gamut signal processing unit 103-2 performs processing for making the signal processed by the first color gamut signal processing unit 103-1 correspond to the second color gamut, and its block configuration is shown in FIG. .

  In FIG. 8, reference numeral 801 denotes a YC gain correction unit that corrects the luminance and the gain of the color difference signal in accordance with data of a three-dimensional LUT described later.

  Reference numeral 802 denotes a three-dimensional reference table, a so-called look-up table (hereinafter referred to as LUT), which has gain correction data corresponding to a three-dimensional signal composed of three signals of the input luminance signal Y_ex and color difference signals Cr_ex and Cb_ex. Have.

  An example of the gain correction operation of the second color gamut signal processing unit having such a configuration will be described with reference to FIG.

  FIG. 9 is an enlarged view of a portion indicated by a broken line region 703 in FIG. Note that the correction is originally three-dimensional correction based on luminance and color difference, but here, in order to simplify the description, a two-dimensional diagram shown in FIG. 9 will be used.

  For example, the luminance signal Y_ex and the color difference signals Cr_ex and Cb_ex are set to values such as P901, P902, and P903 in FIG. In this case, referring to the LUT gain correction data, each of them is converted into P901 ', P902', and P903 ', and correction processing is performed so as to enter the area 702.

  That is, by performing such gain correction processing, all signals existing outside the area 702 in FIG. 7 are compressed inside the area 702, and all signals are BT. 709 is compressed into the color gamut.

  Note that the method of compressing to a specific color gamut by gain correction in this way does not necessarily have to be a correction pattern as shown in FIG. For example, there are various methods for gamut compression, such as a gamut compression method that minimizes the color difference before and after compression, a gamut compression method that maintains luminance, and a gamut compression method that maintains hue. Are known.

  Also, as indicated by 1001 to 1003 in FIG. 10A, gain correction LUTs corresponding to a plurality of color gamut compression methods are recorded in the memory 111, and the user determines which type of color gamut compression method to use. You may make it the structure which can be selected. In that case, the type of gain correction LUT selected by the user may be read from the memory 111 into the three-dimensional LUT indicated by 802 in FIG.

  The second color gamut signal processing unit 103-2 causes the BT. The luminance signal Y_709 and the color difference signals Cr_709 and Cb_709 converted into the color gamut 709 are output from the terminal 103b of the camera signal processing unit 103. Then, the signals are input to the terminal 104b of the first selection unit 104 and the terminal 105b of the second selection unit 105, respectively.

  Next, operations of the first selection unit 104 and the second selection unit 105 to which signals processed by the two color gamuts are input will be described.

  11A and 11B illustrate menu screens for selecting the color gamut of the image display unit and the image recording unit.

  In the figure, reference numeral 1101 denotes a part for selecting a color gamut of an image to be displayed on the image display unit 106, and reference numeral 1102 denotes a part for selecting a color gamut of an image to be recorded. In addition, each of these can change the selection state independently.

  In the example of FIG. 11A, the image display unit 106 is selected to display in the xvYCC color gamut, and the recorded image is BT. A state in which recording in the color gamut 709 is selected is shown.

  In the example of FIG. 11B, the image display unit 106 has BT. It is selected that display in the 709 color gamut is selected, and the recorded image is selected to be recorded in the xvYCC color gamut.

  When setting is made as shown in FIG. 11A, the system controller 109 outputs a control signal to the first selection unit 104 so as to select the signal of the terminal 104a, and the terminal 105ab to the second selection unit 104. A control signal is output so as to select a signal.

  As a result, a display image processed in the xvYCC color gamut is displayed on the image display unit 106, and the BT. A recorded image processed in the color gamut 709 is output.

  When the operation unit 110 is set as shown in FIG. 11B, the system controller 109 outputs a control signal to the first selection unit 104 so as to select the signal of the terminal 104b, and the second selection unit. A control signal is output to 104 so as to select the terminal 105a signal.

  As a result, the BT. A display image processed in the 709 color gamut is displayed, and a recorded image processed in the xvYCC color gamut is output to the image recording unit 107.

  First or second selection in which each of the image display unit 106 and the image recording unit 107 selects an image with respect to a plurality of image signals processed in the camera signal processing unit 103 in accordance with a plurality of color gamuts in this way. Each of the selection units can independently select an image signal.

  That is, even when the video camera is recording a moving image, the selection state of the second selection unit 105 is maintained, and only the first selection unit 104 is switched to the image display unit 106 to display the xvYCC color gamut or BT. . Images processed in the 709 color gamut can be arbitrarily switched and displayed.

  Therefore, even during image recording, it is possible to switch and display an image processed in a plurality of color gamuts on the image display unit 106 without affecting the recorded image.

  FIG. 12 shows a display example by the image display unit of the present embodiment. As shown by 1201, the color gamut information of the image selected by the image recording unit 107 (REC) and the image display unit 106 (EVF) is shown. You may make it the structure which can display and a user can visually recognize.

  In addition, the color gamut is switched by making the image display unit 106 display a primary color point (chromaticity point) of the widest color gamut among a plurality of color gamuts that can be processed by the camera signal processing unit 103. It is possible to make it easier to recognize a change in color in some cases.

  In addition, when image recording is started in a state where the color gamut of the recorded image and the image displayed on the image display unit 106 is different, the gamut information 1201 in FIG. You may be warned.

  Furthermore, the color gamut processed by the second color gamut signal processing unit 103-2 is set to BT. The configuration is not limited to 709 and may be compressed to a plurality of other color gamuts narrower than the first color gamut.

  That is, as indicated by 1021 to 1023 in FIG. In addition to 709, gain correction LUTs corresponding to a plurality of other color gamuts (for example, AdobeRGB) narrower than xvYCC are stored. Then, it may be configured such that the user can select which type of color gamut to compress.

  In this embodiment, the example in which the luminance signal Y_ex and the color difference signals Cr_ex and Cb_ex processed by the first color gamut signal processing unit 103-1 are input to the second color gamut signal processing unit 103-2 has been described. The processing method in the second color gamut signal processing unit 103-2 is not limited to this. For example, as shown in FIG. 13, an RGB signal that has been gamma processed by the first color gamut signal processing unit 103-1 may be input to perform color gamut compression. In that case, the three-dimensional LUT 1302 in FIG. 13 may be configured to hold a gain correction value for correcting each RGB.

  Further, the example in which the camera signal processing unit 103 is provided with the two color gamut signal processing units 103-1 and 103-1 has been described, but three or more color gamut signal processing units may be provided. In this case, the image signal processed by each color gamut signal processing unit may be configured so that the image display unit 106 and the image recording unit 107 can arbitrarily select them independently.

  The color gamut to be processed is xvYCC and BT. Although not limited to 709, AdobeRGB, WideGamutRGB, ITU-R BT. It goes without saying that other color gamuts such as 601 may be used.

[Other Embodiments]
Further, the present invention can be applied when each signal processing unit is implemented by hardware or by software processing using a computer, and similar effects can be obtained. In this case, the program code itself of the software realizes the functions of the above-described embodiment. The program code itself and means for supplying the program code to the computer (for example, a storage medium storing the program code) constitute the present invention. As a storage medium for storing the program code, for example, a floppy (registered trademark) disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

  The functions of the above-described embodiments are not only realized by executing the program code supplied by the computer. That is, the program code is also included in the embodiment of the present invention even when the function shown in the above-described embodiment is realized in cooperation with the OS or other application software running on the computer. Needless to say.

  Further, the supplied program code is stored in a memory provided in a function expansion board of the computer or a function expansion unit connected to the computer. Thereafter, the CPU or the like provided in the function expansion board or function expansion unit performs part or all of the actual processing based on the instruction of the program code, and the functions of the above-described embodiments are realized by the processing. It is included in the present invention.

In order to solve the above problems, an imaging apparatus of the present invention includes an imaging unit that captures an image of a subject, and a signal processing unit that performs processing corresponding to a plurality of color gamuts on image data obtained by the imaging unit When an image recording means for recording the image data processed by said signal processing means in a storage medium, and image display means for displaying the image data processed by said signal processing means, an image to be recorded before Symbol image recording means a first selecting means for selecting a color gamut data, and a second selecting means for selecting a color gamut of image data to be displayed before Symbol image display means, the image data thus being recorded on the image recording unit Regardless of the color gamut, the second selection means can select the color gamut of the image data displayed on the image display means .

According to the present invention, without even during image recording to change the color gamut of recorded images, it is possible display the images of different color gamut than the recorded image. Therefore, it is possible to display by switching the image when treated with a color gamut of Ku number multiple things affect the color of the recorded image.

The processing method of the first color gamut signal processing unit in this embodiment is BT. 709 is a processing method for a signal having a color gamut wider than the primary color points of R, G, and B defined in 709, and details thereof are described in Non-Patent Document 1 and Patent Document 1 described above. Only the outline of will be described.

Claims (1)

Imaging means for capturing an image of a subject;
A signal processing unit that performs processing according to a plurality of color gamuts on the image data obtained by the imaging unit;
An image recording unit for recording image data processed by the signal processing unit;
An image display unit for displaying the image data processed by the signal processing unit;
A first selection means for selecting a color gamut of image data to be recorded in the image recording unit from the plurality of color gamuts;
Second selection means for selecting a color gamut of image data to be displayed on the image display unit from the plurality of color gamuts,
An image pickup apparatus, wherein a color gamut of image data to be displayed on the image display unit can be selected by the second selection unit regardless of a color gamut of image data being recorded in the image recording unit.

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