JP2011109360A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus which easily corrects a specific color in a photographed image to a color of an actual object in detail in photographing. <P>SOLUTION: The imaging apparatus is provided with: a hue setting part 60 which sets a hue area to a color space; a hue rotation amount setting part 61 which sets a hue rotation amount to the color space; and a saturation change amount setting part 62 which sets a saturation change amount to the color space, and a specific color correction control part 63 changes a hue and saturation to the specific color in an image displayed on a liquid crystal monitor 9 on the basis of the hue rotation amount of the set hue area to be input and set saturation change amount setting information by setting an arbitrary hue area to the hue setting part 60, setting an arbitrary hue rotation amount to the hue rotation amount setting part 61, and further setting an arbitrary saturation change amount to the saturation change amount setting part 62 by pressing operations of a menu button 12 and a setting switching button 13. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an imaging apparatus such as a digital still camera and a digital video camera.

  In a digital still camera (hereinafter referred to as “digital camera”), when a subject image is incident on an image sensor such as a CCD through a photographing lens system, a signal processing unit performs a predetermined process on an image signal output from the image sensor. By performing signal processing, image data corresponding to the subject image can be obtained. Further, processing for displaying the obtained image data on a display unit (monitor screen) and processing for saving in a memory or the like are performed.

  In addition, recently, even a beginner who does not have specialized knowledge about shooting has a plurality of shooting modes so that images with appropriate image quality can be easily obtained according to various shooting scenes. A digital camera is also proposed (see, for example, Patent Document 1).

  In the imaging apparatus (camera apparatus) as in Patent Document 1, when a user sets a predetermined shooting mode, image quality parameters (saturation, hue, sharpness, contrast, white balance, etc.) corresponding to the shooting mode are set. Image data processing is performed. By the way, the image quality parameters (saturation, hue, sharpness, contrast, white balance, etc.) are stored as parameter values that are initially set so as to obtain an optimum image quality corresponding to a plurality of shooting modes.

  For this reason, when the specific color in the captured image displayed on the display unit (monitor screen) differs from the actual subject color depending on the shooting conditions, the specific color in the captured image is actually The color of the subject could not be corrected.

  Accordingly, an object of the present invention is to provide an imaging apparatus that can easily and in detail correct a specific color in a captured image to an actual subject color at the time of shooting.

  In order to achieve the above object, an imaging apparatus according to claim 1 captures image data corresponding to a captured subject image output from the imaging unit that captures a subject image, and outputs the image data to the image data. In an image forming apparatus having image processing means for performing image processing and image display means for displaying an image processed by the image processing means, a hue area setting means for setting a hue area with respect to a color space A hue rotation amount setting means for setting a hue rotation amount for the color space, a saturation change amount setting means for setting a saturation change amount for the color space, and an arbitrary value for the hue area setting means A first setting input means for setting a hue area; a second setting input means for setting an arbitrary hue rotation amount for the hue rotation amount setting means; and a saturation change amount setting means. Leave Third setting input means for setting the saturation change amount of the image, and color correction control means for changing the hue and saturation for a specific color in the image displayed on the image display means. The color correction control means sets an arbitrary hue area for the hue area setting means by the first setting input means, and sets the hue rotation amount setting means by the second setting input means. By setting an arbitrary hue rotation amount, and further setting an arbitrary saturation change amount with respect to the saturation change amount setting means by the third setting input means, the input of the set hue region to be input Based on the hue rotation amount and the set saturation change amount setting information, the hue and saturation are changed for a specific color in the image displayed on the image display means.

  The imaging apparatus according to claim 2, when an arbitrary hue region is set for the hue region setting unit by the first setting input unit, a chart indicating a color space is displayed on the image display unit, The hue area start angle and end angle are set by the first setting input means on the displayed color space chart screen.

  The imaging apparatus according to claim 3, wherein when an arbitrary hue rotation amount is set for the hue rotation amount setting unit by the second setting input unit, a chart indicating a color space is displayed on the image display unit. The hue area start angle and end angle after the hue rotation are set by the second setting input means on the displayed color space chart screen.

  The image pickup apparatus according to claim 4, wherein an arbitrary saturation change amount is set for the saturation change amount setting unit by the third setting input unit, and a saturation change amount is set in the image display unit. The displayed percentage is displayed, and the saturation change amount is set by the third setting input means on the displayed saturation change amount percentage screen.

  According to the imaging device of claim 1, even when the specific color in the captured image differs from the actual subject color depending on the captured state or the like for the captured image displayed on the image display unit, A specific color in the captured image can be easily corrected to the color of the subject.

  According to the imaging apparatus of the second aspect, the user is displayed by setting the hue region start angle and end angle by the first setting input means on the color space chart screen displayed on the image display means. It is possible to make settings while viewing the color space chart screen.

  According to the imaging apparatus of claim 3, by setting the hue region start angle and the end angle after the hue rotation on the color space chart screen displayed on the image display means by the second setting input means, The user can make settings while viewing the displayed color space chart screen, and the setting operation can be easily performed.

  According to the imaging apparatus of the fourth aspect, the user is displayed by setting the saturation change amount by the third setting input means on the saturation change amount percentage screen displayed on the image display means. This can be set while looking at the saturation change amount percentage screen, and the setting operation can be easily performed.

(A) is a front view which shows the digital camera as an example of the imaging device which concerns on Embodiment 1 of this invention, (b) is the top view, (c) is the back view. 1 is a block diagram showing an outline of a system configuration in a digital camera as an example of an imaging apparatus according to Embodiment 1 of the present invention. The block diagram which shows the structure of an image data process part. (A) is a figure which shows an example of the gamma correction curve at the time of performing input-output conversion processing in a gamma correction process part, (b) is a figure which shows an example of the output characteristic of the output signal with respect to the input signal in an image output device. . The figure which shows an example of CbCr color space. The block diagram which shows the structure of an edge emphasis processing part. The block diagram which shows the hue setting part, the hue rotation amount setting part, the saturation change amount setting part, and the specific color correction control part which were provided in the control part. 5 is a flowchart showing color correction control for a specific color in the present embodiment. 6 is a flowchart illustrating hue change setting processing according to the present embodiment. (A) is a diagram showing an example of area setting before hue change in the CbCr color space, and (b) shows an example of area setting after hue change in the CbCr color space. (A) is a diagram showing an example in which the size of the pre-hue change area and the post-hue change area is the same in the CbCr color space, and (b) is the size of the pre-hue change area and the post-hue change area in the CbCr color space. The figure which showed an example when is different.

  Hereinafter, the present invention will be described based on the illustrated embodiments. 1 is a front view showing a digital camera as an example of an imaging apparatus according to an embodiment of the present invention, FIG. 1B is a top view thereof, FIG. 1C is a rear view thereof, and FIG. It is a block diagram which shows the outline | summary of the system configuration | structure in the digital camera shown to Fig.1 (a), (b), (c).

(Appearance structure of digital camera)
As shown in FIGS. 1A, 1B, and 1C, a release button (shutter button) 2, a power button 3, a shooting / playback switching dial 4 are provided on the upper surface side of the digital camera 1 according to the present embodiment. In the front (front) side of the digital camera 1, a lens barrel unit 6 having a photographing lens system 5, a strobe light emitting unit (flash) 7, and an optical viewfinder 8 are provided.

  On the back side of the digital camera 1, there are a liquid crystal monitor (LCD) 9, an eyepiece 8 a of the optical viewfinder 8, a wide-angle zoom (W) switch 10, a telephoto zoom (T) switch 11, and a menu (MENU) button 12. , A setting switching button 13 and the like are provided. Further, a memory card storage unit 15 for storing a memory card 14 (see FIG. 2) for storing captured image data is provided inside the side surface of the digital camera 1.

(Digital camera system configuration)
As shown in FIG. 2, the digital camera 1 includes a CCD 20 serving as a solid-state imaging device on which a subject image incident through a photographing lens system 5 of a lens barrel unit 6 is formed on a light receiving surface, and electrical signals output from the CCD 20. An analog front-end unit (hereinafter referred to as “AFE unit”) 21 that processes (analog RGB image signal) into a digital signal, a signal processing unit 22 that processes a digital signal output from the AFE unit 21, and temporarily stores data SDRAM 23 for controlling, ROM 24 for storing a control program, a motor driver 25 for driving the lens barrel unit 6 and the like.

  The lens barrel unit 6 includes a photographic lens system 5 having a zoom lens, a focus lens, and the like, an aperture unit 26, and a mechanical shutter unit 27. The drive units of the photographic lens system 5, the aperture unit 26, and the mechanical shutter unit 27 are as follows. It is driven by the motor driver 25. The motor driver 25 is driven and controlled by a drive signal from a control unit (CPU) 28 of the signal processing unit 22.

  In the CCD 20, RGB primary color filters (not shown) are arranged on a plurality of pixels constituting the CCD 20, and electrical signals (analog RGB image signals) corresponding to the three primary colors of RGB are output.

  The AFE unit 21 is sampled by a TG (timing signal generating unit) 30 that drives the CCD 20, a CDS (correlated double sampling unit) 31 that samples an electrical signal (analog RGB image signal) output from the CCD 20, and the CDS 31. An AGC (analog gain controller) 32 that adjusts the gain of the image signal, and an A / D converter 33 that converts the image signal gain-adjusted by the AGC 32 into a digital signal (hereinafter referred to as “RAW-RGB data”) are provided. Yes.

  The signal processing unit 22 receives the output of the screen horizontal synchronization signal (HD), the screen vertical synchronization signal (VD), and the pixel transfer clock (pixel clock) from the TG 30 of the AFE unit 21, and in accordance with these synchronization signals, A CCD interface (hereinafter referred to as “CCD I / F”) 34 that captures RAW-RGB data output from the A / D converter 33 of the AFE unit 21, a memory controller 35 that controls the SDRAM 23, and the captured RAW-RGB data Is converted into image data that can be displayed and recorded, a resizing processor 37 that changes the image size according to the size of the image data to be displayed and recorded, and the image data is displayed on a liquid crystal monitor ( LCD) Display output control unit 38 for display output and image data recorded by JPEG formation or the like A data compression unit 39 for writing, a media interface (hereinafter referred to as “media I / F”) 40 for reading image data to the memory card 14 or reading image data written to the memory card 14, and an operation unit 41. And a control unit 28 that performs system control of the entire digital camera 1 based on a control program stored in the ROM 24 based on the operation input information.

  The operation unit 41 includes a release button 2, a power button 3, a shooting / playback switching dial 4, and a wide-angle zoom provided on the external surface of the digital camera 1 (see FIGS. 1A, 1B, and 1C). The switch 10, the telephoto zoom switch 11, the menu button 12, the setting switch button 13, and the like. A predetermined operation instruction signal is input to the control unit 28 by the photographer's operation.

  The SDRAM 23 stores the RAW-RGB data captured by the CCD I / F 34 and converts the YUV data (RAW-RGB data, luminance data (Y) and color difference component image data converted by the image data processing unit 36. (YCbCr data converted into (Cb, Cr)) is stored, and further, image data such as JPEG formation compressed by the data compression unit 39 is stored.

(Image data processing during subject shooting)
Next, image data processing at the time of subject shooting by the digital camera 1 will be described.

  When the user (photographer) turns on the power button 3 and sets the photographing / playback switching dial 4 to the photographing mode, the digital camera 1 is activated in the recording mode. When the control unit 28 detects that the power button 3 is turned on and the shooting / playback switching dial 4 is set to the shooting mode, the control unit 28 outputs a control signal to the motor driver 25 to switch the lens barrel unit 6. The camera 20 is moved to a photographing position, and the CCD 20, AFE unit 21, signal processing unit 22, SDRAM 23, ROM 24, liquid crystal monitor 9 and the like are activated.

  Then, by directing the photographic lens system 5 of the barrel unit 6 toward the subject, a subject image incident through the photographic lens system 5 is formed on the light receiving surface of each pixel of the CCD 20. Then, an electrical signal (analog RGB image signal) corresponding to the subject image output from the CCD 20 is input to the A / D conversion unit 33 via the CDS 31 and the AGC 32, and is converted into RAW-RGB data by the A / D conversion unit 33. Convert. This RAW-RGB data is taken into the CCD I / F 34 of the signal processing unit 22 and stored in the SDRAM 23 via the memory controller 35.

  The CCD I / F 34 of the signal processing unit 22 calculates an AF (automatic focus) evaluation value, an AE (automatic exposure) evaluation value, and an AWB (auto white balance) evaluation value from the captured RAW-RGB data.

  The AF evaluation value is calculated by, for example, the output integrated value of the high frequency component extraction filter or the integrated value of the luminance difference between adjacent pixels. When in the in-focus state, the edge portion of the subject is clear, so the high frequency component is the highest. By utilizing this, at the time of AF operation (at the time of focus detection operation), an AF evaluation value at each focus position of the taking lens system 5 is acquired, and the AF operation is performed with the point where the maximum is obtained as the focus detection position. Executed.

  The AE evaluation value and the AWB evaluation value are calculated from the integrated values of the RGB values in the RAW-RGB data. For example, the screen corresponding to the light receiving surfaces of all the pixels of the CCD 20 is equally divided into 256 areas (16 horizontal divisions and 16 vertical divisions), and the RGB integration of each area is calculated. Then, the control unit 28 reads the calculated RGB integrated value, and in the AE process, calculates the luminance of each area of the screen and determines an appropriate exposure amount from the luminance distribution. Based on the determined exposure amount, exposure conditions (the number of electronic shutters of the CCD 20, the aperture value of the aperture unit 26, etc.) are set. In the AWB process, an AWB control value that matches the color of the light source of the subject is determined from the RGB distribution.

  When a still image shooting operation in which the release button 2 is pressed (half-pressed to fully pressed) is started, a still image recording process is performed.

  That is, when the release button 2 is pressed (half-pressed to full-pressed), the focus lens of the photographing lens system 5 is moved by a drive command from the control unit 28 to the motor driver 25, and is referred to as so-called hill-climbing AF, for example. The contrast evaluation AF operation is executed. When the AF (focusing) target range is the entire region from infinity to close, the focus lens of the photographing lens system 5 moves to each focus position from close to infinity, or from infinity to close, and CCDI / The control unit 28 reads out the AF evaluation value at each focus position calculated in F34. Then, the focus lens is moved to the in-focus position with the point where the AF evaluation value at each focus position is maximized as the in-focus position, and in-focus.

  Then, the AE process described above is performed, and when the exposure is completed, the mechanical shutter unit 27 is closed by a drive command from the control unit 28 to the motor driver 25, and an analog RGB image signal for a still image is output from the CCD 20. Then, it is converted into RAW-RGB data by the A / D conversion unit 33 of the AFE unit 21.

  The RAW-RGB data is taken into the CCD I / F 34 of the signal processing unit 22, converted into YUV data by an image data processing unit 36 described later, and stored in the SDRAM 23 via the memory controller 35. The YUV data is read from the SDRAM 23, converted into a size corresponding to the number of recorded pixels by the resizing processing unit 37, and compressed into image data such as JPEG format by the data compression unit 39. The compressed image data such as JPEG format is written back to the SDRAM 23, read out from the SDRAM 23 through the memory controller 35, and stored in the memory card 14 through the media I / F 40.

  As shown in FIG. 3, a white balance (WB) processing unit 50, γ for converting the captured RAW-RGB data into image data that can be displayed and recorded and outputting the image data to the image data processing unit 36. A correction processing unit 51, an interpolation processing unit 52, a YCbCr conversion processing unit 53, a color correction processing unit 54, and an edge enhancement processing unit 55 are provided.

  Based on the AWB evaluation value calculated by the CCD I / F 34, the white balance (WB) processing unit 50 adjusts the white balance according to the color of the light source of the subject from the distribution of the RGB filters arranged on all the pixels of the CCD 20. WB processing for determining the control value is performed to adjust the white balance.

  That is, a color filter of any one of R (red), G (green), and B (blue) is Bayer-arranged in each pixel of the CCD 20 that accumulates the amount of light from the subject. Since the amount of transmitted light varies depending on the amount of charge, the amount of charge accumulated in each pixel differs. In the RGB color filter with the Bayer arrangement, the G filter has the highest pixel sensitivity, and the R and B filters have about half the pixel sensitivity compared to the G filter. Therefore, in the WB processing, processing for multiplying the output from the R filter and B filter pixels is performed in order to compensate for the pixel sensitivity difference between these color filters and to make white in the captured image appear white.

  In addition, since the color of the object changes depending on the light source color (for example, sunlight, fluorescent lamp, etc.), the white balance (WB) processing unit 50 is configured to use an R filter so that the white color looks white even if the light source changes. It has a function of changing and controlling the gain applied to the output from the pixel of the B filter.

  The γ correction processing unit 51 performs input / output conversion processing on each pixel output data whose white balance is adjusted by the white balance (WB) processing unit 50 by using, for example, a γ correction curve as shown in FIG. Do. In FIG. 4A, the horizontal axis is an input signal, and the vertical axis is an output signal.

  That is, in the image output device such as the liquid crystal monitor (LCD) 9 of the digital camera 1, for example, as shown in FIG. 4B, the output signal is output with nonlinear characteristics with respect to the input signal. In FIG. 4B, the horizontal axis represents the input signal, and the vertical axis represents the output signal. In the case of such a non-linear output, the gradation of displayed images is different. Therefore, a γ correction process is performed on the input signal in advance so that the output characteristics of the image output apparatus maintain linearity.

  The interpolation processing unit 52 performs an interpolation calculation process for interpolating from the surrounding pixels in order to supplement the missing two colors of data with respect to the raw data having only one color of data per pixel.

  The YCbCr conversion processing unit 53 performs processing for converting RGB data into YUV data (hereinafter referred to as “YCbCr data”) that can be displayed and recorded.

That is, in a JPEG image of a file format generally used in a digital camera or the like, an image is created from YCbCr data, so it is necessary to convert RGB data to YCbCr data. As this conversion formula, for example, the following formula can be used.
Y = 0.299 × R + 0.587 × G + 0.114 × B
Cb = −0.299 × R + 0.587 × G + 0.886 × B
Cr = 0.701 × R−0.587 × G−0.114 × B

  Examples of color correction processing performed by the color correction processing unit 54 include saturation setting, hue setting, partial hue change setting, and color suppression setting.

  Saturation setting is a parameter setting process for determining color intensity. For example, in the CbCr color space as shown in FIG. 5, R (red) from the origin with respect to the color of R (red) in the second quadrant. The longer the vector length to the dot, the darker the color. The hue setting is a parameter setting process for determining a hue. For example, in the CbCr color space of FIG. 5, even if the vector length is the same for the G (green) color in the third quadrant, The hue changes if the orientation is different.

  The partial hue change setting is, for example, a process of partially rotating the color area as shown in the fourth quadrant in the CbCr color space of FIG. Further, when the saturation is strong, the color becomes darker, while the color noise tends to become stronger. Therefore, the color suppression setting is a process for suppressing color noise by setting a threshold value for a luminance signal, for example, and suppressing saturation for an area lower or higher than the threshold value.

  The edge enhancement processing unit 55 is a process for performing edge enhancement in accordance with the image on the YCbCr data converted by the YCbCr conversion processing unit 53. As shown in FIG. 6, the edge enhancement processing unit 55 extracts an edge portion from the luminance (Y) signal of the image, and multiplies the edge extracted by the edge extraction filter unit 56 with a gain. The gain multiplication unit 57, the low-pass filter (LPF) unit 58 that removes image noise in parallel with the edge extraction in the edge extraction filter unit 56, the edge extraction data after gain multiplication and the image data after low-pass filter processing An adder 59 for adding is provided.

  Note that the strength of the edge is determined by the gain of the gain multiplier 57, and the edge becomes stronger when the gain is large, and the edge becomes weak when the gain is small.

  During the normal photographing, the image data processing unit 36 controls the image data (white balance (WB) processing, γ correction processing, interpolation processing, YCbCr conversion processing, color correction processing, edge enhancement processing) under the control of the control unit 28. ) Is automatically performed.

  In the present embodiment, a specific color (hereinafter, referred to as “color”) in the captured image is captured with respect to the captured image displayed on the liquid crystal monitor 9 via the display output control unit 38 after the subject is captured and the image data is processed. As shown in FIG. 7, a hue region is set for the color space in the control unit 28 of the digital camera 1 so that color correction (change of hue and saturation) can be performed for “specific color”. The hue setting unit 60, the hue rotation amount setting unit 61 that sets the hue rotation amount with respect to the color space, the saturation change amount setting unit 62 that sets the saturation change amount with respect to the color space, and the liquid crystal monitor 9 A specific color correction control unit 63 that performs color correction control on a specific color in the displayed captured image is provided.

  In the present embodiment, when the “specific color correction setting mode” is set by pressing the menu button 12 and the setting switching button 13 of the digital camera 1 when performing color correction on a specific color, the liquid crystal monitor 9 is set. A chart indicating the CbCr color space and a percentage indicating the saturation change amount can be displayed. In the present embodiment, the first, second, and third setting input means correspond to the menu button 12 and the setting switching button 13.

(Color correction (change of hue and saturation) control for specific colors)
Color correction (change of hue and saturation) control for a specific color in the present embodiment will be described with reference to a flowchart shown in FIG.

  When the user photographs a subject with the digital camera 1, the photographed image is displayed on the liquid crystal monitor 9 through the display output control unit 38 by the image data processing described above. At this time, the specific color in the captured image displayed on the liquid crystal monitor 9 may be different from the color of the actual subject directly viewed by the user depending on the shooting situation or the like.

  Therefore, in such a case, the user wants to correct the color of the specific color in the captured image so that the user matches the actual color of the subject at the time of shooting with the specific color in the captured image displayed on the liquid crystal monitor 9. When the determination is made, the menu button 12 and the setting switch button 13 are pressed to switch to the “specific color correction setting mode” on the screen of the liquid crystal monitor 9 (step S1). When the mode is switched to the “specific color correction setting mode” in step S1, hue change setting is first performed (step S2).

  In the hue change setting process in step S2, as shown in the flowchart of FIG. 9, in order to set the hue area to be changed first, the start angle setting before the change and the end angle setting before the change are performed (step S11). ). That is, for example, as shown in FIG. 10A, a CbCr color space is displayed on the screen of the liquid crystal monitor 9, and when the user presses the menu button 12 and the setting switch button 13, the hue setting unit 60 Then, the start angle θ1 and end angle θ2 of the region in which the hue is changed in the CbCr color space (the first quadrant in the figure) on this screen are set.

  Then, when it is determined that there is OK in the region between the start angle A1 before change and the end angle A2 before change set in step S11 (step S12), as shown in FIG. Is set with the changed start angle θ3 and the changed end angle θ4 (step S13). Then, it is determined that the area is between the changed start angle θ3 and the changed end angle θ4 set by the photographer in step S13 (step S14).

  When the hue change setting in step S2 is completed (step S3), the saturation change setting is then performed (step S4). That is, the user presses the menu button 12 and the setting switch button 13 to set the saturation change amount for the current saturation on the screen of the liquid crystal monitor 9 and display the set saturation change amount as a percentage.

  When the saturation change setting in step S4 ends (step S5), the specific color correction control unit 63 inputs the hue rotation amount setting information set in step S2 and the saturation change set in step S4. Based on the setting information, color correction (change in hue and saturation) is controlled for a specific color, and the specific color in the photographed image is corrected to match the actual subject color (step S6). After the color correction for the specific color is performed in step S6, a photographed image whose color is corrected so that the color of the specific color matches the color of the actual subject is displayed on the liquid crystal monitor 9.

As a method for correcting the color of the specific color in step S6 (changing the hue and saturation for the specific color), for example, as shown in FIG. 11A, an area before changing the hue (before changing the hue). Simple hue rotation when the size of the area after the hue change (the area between the start angle θ1 and the end angle θ2) and the area after the hue change (area between the start angle θ3 and the end angle θ4 after the hue change) are the same To do. The angle between the start angle θ1 of the region before hue change and the start angle θ3 of the region after hue change is θ5, the color information before color correction is Cb, Cr, and the color information after color correction is Cb ′, Cr When the saturation change amount is A (%), the color information (Cb ′, Cr ′) after the color correction of the specific color can be calculated from the following equation.
Cb ′ = (cos θ5 × Cb−sin θ5 × Cr) × A / 100
Cr ′ = (sin θ5 × Cb + cos θ5 × Cr) × A / 100

  Further, for example, as shown in FIG. 11B, the area before the hue change (area between the start angle θ1 and the end angle θ2 before the hue change) and the area after the hue change (hue change). When the sizes of the subsequent start angle θ3 and the end angle θ4 are different (in FIG. 11B, the post-hue change area is larger), the calculation can be performed as follows.

That is, the angle between the start angle θ1 and the end angle θ2 of the region before hue change is θa, the angle between the start angle θ3 and the end angle θ4 of the region after hue change is θb, and the angle of color information for color correction is θ. Assuming that the color information before color correction is Cb, Cr, the color information after color correction is Cb ′, Cr ′, and the saturation change amount is A (%), the color information (Cb ′, Cr ′) can be calculated from the following equation.
Cb ′ = (cos θ6 × Cb−sin θ6 × Cr) × A / 100
Cr ′ = (sin θ6 × Cb + cos θ6 × Cr) × A / 100
However, θ6 = (θ−θ1) × θb / θa + (θ3−θ1)

  As described above, according to the present embodiment, when a user captures a subject with the digital camera 1, a captured image displayed on the liquid crystal monitor 9 via the display output control unit 38 by image data processing is captured. Even if the specific color in the photographed image differs from the actual subject color depending on the situation or the like, the user sets an arbitrary color space region and displays the hue rotation amount and saturation change amount on the screen of the liquid crystal monitor 9. Therefore, the specific color in the captured image can be corrected easily and in detail according to the color of the subject. Therefore, faithful color reproducibility can be obtained.

  In the above embodiment, the color space is described as the CbCr space, but the present invention is not limited to this.

1 Digital camera (imaging device)
5 Shooting Lens System 9 LCD Monitor 12 Menu Button 13 Setting Switch Button 20 CCD
21 Analog front end unit 22 Signal processing unit 28 Control unit 36 Image data processing unit 60 Hue setting unit 61 Hue rotation amount setting unit 62 Saturation change amount setting unit 63 Specific color correction control unit

JP 2004-48786 A

Claims (4)

An imaging unit that captures a subject image, an image processing unit that captures image data corresponding to the captured subject image output from the imaging unit, and performs image processing on the image data, and image processing by the image processing unit In an image forming apparatus having an image display means for displaying a processed image,
A hue area setting means for setting a hue area for the color space;
A hue rotation amount setting means for setting a hue rotation amount with respect to the color space;
A saturation change amount setting means for setting a saturation change amount for the color space;
First setting input means for causing the hue area setting means to set an arbitrary hue area;
A second setting input means for causing the hue rotation amount setting means to set an arbitrary hue rotation amount;
Third setting input means for causing the saturation change amount setting means to set an arbitrary saturation change amount;
Color correction control means for changing the hue and saturation for a specific color in the image displayed on the image display means,
The color correction control means sets an arbitrary hue area for the hue area setting means by the first setting input means, and arbitrarily sets the hue rotation amount setting means by the second setting input means. The hue rotation amount of the set hue area to be input is set by setting an arbitrary saturation change amount for the saturation change amount setting means by the third setting input means. An image formation characterized by changing a hue and saturation for a specific color in an image displayed on the image display means based on a rotation amount and the set saturation change amount setting information apparatus.   When an arbitrary hue area is set for the hue area setting means by the first setting input means, a chart showing a color space is displayed on the image display means, and the chart showing the color space is displayed on the displayed color space chart screen. 2. The image forming apparatus according to claim 1, wherein the hue area start angle and end angle are set by the first setting input means.   When an arbitrary hue rotation amount is set for the hue rotation amount setting means by the second setting input means, a chart showing a color space is displayed on the image display means, and the displayed color space chart screen 2. The image forming apparatus according to claim 1, wherein the hue area start angle and end angle after hue rotation are set by the second setting input means.   When an arbitrary saturation change amount is set for the saturation change amount setting means by the third setting input means, a percentage indicating the saturation change amount is displayed on the image display means, and the displayed saturation is displayed. The image forming apparatus according to claim 1, wherein a saturation change amount is set by the third setting input unit on a degree change amount percentage screen.

Images