JP6632093B2 - Imaging device - Google Patents

Description

  The present invention relates to an imaging device.

A television camera has a function of detecting a specific hue for each pixel and correcting a specific hue for each pixel, referred to as 6-color independent masking or 12-color masking (see Patent Document 1).
Meanwhile, in a single-chip color camera, color tone correction is performed electrically using an RGB gain, a linear matrix, and the like (see Patent Document 4).

Then, the color temperature of the illumination of the subject is calculated from the RGB gain, and the color temperature is displayed on a viewfinder, a monitor image, or the like (see Patent Document 6).
Further, the RGB gain and the linear matrix are changed in proportion to the color temperature of the illumination of the subject (see Patent Document 5).

A linear matrix conversion unit that performs a linear matrix conversion on an input video signal including three primary color components of red, green, and blue; and a linear matrix conversion unit that performs linear matrix conversion on the basis of a difference value between the input video signals of the three primary color components. Set the coefficients used in the matrix conversion unit. The linear matrix coefficient for objects that are close to achromatic can be reduced so that the colors of objects that are close to achromatic are not changed unnecessarily, and color correction can be performed as usual for objects that have high saturation. .
However, with the RGB gain and the linear matrix, it is difficult to make fine adjustments such as 12-color masking for detecting a specific hue for each pixel and correcting the specific hue for each pixel.

  Furthermore, in linear matrix, or in 12-color masking in which a specific hue is detected for each pixel and a specific hue is corrected for each pixel, when the color correction is performed, B noise that is noisy under low color temperature illumination becomes R noise. And G, and the execution S / N decreases. When color temperature correction is performed electrically under high color temperature illumination, the noisy R noise is mixed into B and G, and the execution S / N is reduced. Therefore, a linear matrix is generated from the LPF signal (see Patent Literature 2 and Patent Literature 3).

  In the visual characteristic color band, luminances Y and G are wide, and R, B, RY, and BY are narrow (see Non-Patent Document 1). However, video signals of R, B, RY, and BY require a band equivalent to Y, so-called 4: 4: 4, due to chroma key processing or the like. As a compromise, the so-called 4: 2: 2 transmission or recording of the band of the video signal of R, B, RY or BY is half of the band of the video signal of luminance Y or G in general.

JP-A-9-247701 JP 2007-180893 A JP 2008-118373 A JP 2010-171844 A JP-A-2004-320148 JP 2008-199207 A

The Journal of the Institute of Television Engineers of Japan 33 (12), 1008-1013, 1979-11-01 4-2 Color blur perception and chrominance signal band (NHK)

  According to the present invention, when tone correction is performed (either in a linear matrix, or in 12-color masking in which a specific hue is detected for each pixel and a specific hue is corrected for each pixel), the noisy B or R noise becomes It is also an object of the present invention to prevent the execution S / N from lowering and prevent the reduction of the execution S / N, and at the same time maintain the color band of the main line signal, improve the color correction, and maintain the execution S / N.

The present invention relates to an imaging device having a solid-state imaging device,
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Or a means for processing a G video signal and a means for processing a video signal of an RB pixel having an interval twice as long as the interval between G pixels, or a means for transmitting a G video signal and an image of an RB pixel having an interval twice as long as the interval between G pixels Means for transmitting signals, such as means for halving the band of the R image signal and the band of the B image signal with respect to the band of the G image signal. Interpolation is performed using a weighted average (including the median value or the average of the median value and the central pixel) of the central pixel image signal, and at least the bright portion also converts the B image signal into the median value of the peripheral B pixel image signal and the central pixel image. Weighted average with the signal (the median Rui is an image pickup apparatus characterized in that it comprises a color correction means for generating a color correction signal from the signal interpolated by including the average of the said median and the center pixel).

Further, in an imaging device having a solid-state imaging device,
An image sensor with color filters of Bayer array of R, G1, G2, and B and means for processing signals thereof, or a four-plate image sensor of R, G1, G2, and B, a color separation optical system, and means for processing signals thereof are provided. Then, at least in the bright portion, the R image signal is interpolated by the weighted average of the median value of the peripheral R pixel image signal and the central pixel image signal or the R image signal is calculated by dividing the median value of the peripheral R pixel image signal and the central pixel image signal. A signal obtained by interpolating on average, and interpolating the B image signal at least in the bright part by weighted average of the median value of the peripheral B pixel image signal and the central pixel image signal, or interpolating the B image signal by the median value of the peripheral B pixel image signal. An image pickup apparatus comprising a color tone correction means for generating a color tone correction signal from the image data.

Further, in the above imaging device,
RG1G2B and means for transmission (so-called DG transmission) for each color of four systems or R- (G1 + G2), G1, G2, B- (G1 + G2) or R- (Y1 + Y2), Y1, Y2, B- (Y1 + Y2) or R -G1, G1, G2, BG2 or RY1, Y1, Y2, BY2 or RG2, G1, G2, BG1 or RY2, Y1, Y2, BY1 etc. An image pickup apparatus comprising means for transmitting a signal whose luminance is mainly and a signal whose color is mainly.

Further, in the above imaging device,
Means for processing the G video signal and means for processing the video signal of the RB pixel at an interval twice the interval of the G pixel, or means for transmitting the G video signal and the video signal of the RB pixel at an interval twice the interval of the G pixel Transmitting at least one of:
A means for detecting (calculating) a color temperature, and a weighted average of at least a bright portion of the R image signal which is positively correlated with the detected (calculated) color temperature of the median value of the peripheral R pixel image signal and the center pixel image signal. At least in the bright portion, color correction from a signal obtained by interpolating the B image signal with a weighted average negatively correlated with the detected (calculated) color temperature of the median value of the peripheral B pixel image signal and the center pixel image signal. Color tone correction means for generating a signal;
Means for varying the amplification degree of the RGB video signal, and at least the bright portion correlates the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (the center is smaller when the amplification degree is small). When the image signal of the R pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated. Interpolated by a weighted average correlated with the amplification degree of the RGB video signal with the center pixel imaging signal (for a small amplification degree, the center R pixel imaging signal is mainly, and for a large amplification degree, the central value of surrounding R pixel imaging signals is mainly). And a color tone correcting means for generating a color tone correction signal from the obtained signal.

  Also, the present invention provides the image pickup device, wherein an image pickup device with a color filter of RG1G2B array and a signal processing means thereof, or a four-plate image pickup device of RG1G2B and a color separation optical system and means for processing the signal thereof, or Means for processing the G video signal and means for processing the video signal of the RB pixel at an interval twice the interval of the G pixel, or means for transmitting the G video signal and the video signal of the RB pixel at an interval twice the interval of the G pixel Means for reducing the bandwidth of the R video signal and the B video signal to half of the G video signal, such as a means for transmitting the R video signal. The image processing apparatus further includes a color tone correction unit configured to generate a color tone correction signal from a signal obtained by interpolating the average of the B image signal with the pixel image signal and interpolating the B image signal with the median value of every other peripheral B pixel image signal by G pixels. Imaging It is the location.

Further, the present invention provides an imaging device having a solid-state imaging device,
Means for signal processing of RGB signals from the three RGB plates and the color separation optical system, and at least the bright portion is provided with a median value and a central pixel image signal of the surrounding R pixel image signals every other R image signal. Interpolation by weighted average or interpolation of R imaging signals by the average of the median value of center R imaging signals and the center pixel imaging signal of every other surrounding R pixel, and at least the bright part also captures every other B imaging signal of surrounding B pixel. Color tone correction means for generating a color tone correction signal from a signal obtained by interpolating with a weighted average of the median value of the signal and the central pixel or interpolating the B image signal with the median value of every other surrounding B pixel image signal,
R- (G1 + G2), G1, G2, B- (G1 + G2) or R- (Y1 + Y2), Y1, Y2, B- (Y1 + Y2) or R-G1, G1, G2, B-G2 or R-Y1, Y1, Means for transmitting two main signals such as Y2, BY2 or RG2, G1, G2, BG1 or RY2, Y1, Y2, BY1 as a signal whose main luminance is and a main signal of color. An imaging device comprising:

  Further, the present invention provides an image pickup apparatus having a solid-state image pickup device, wherein the image pickup apparatus has three RGB plates and means for signal processing of RGB signals from a color separation optical system. Interpolate by weighted average of the median value of every other surrounding R pixel image signal and the center pixel image signal or interpolate the R image signal by the average of the median value of every other surrounding R pixel image signal and the center pixel image signal , At least in the bright part, the weighted average of the median value of the central B pixel imaging signal and the median value of the peripheral B pixel imaging signal of every other B imaging signal or the median value of the peripheral B pixel imaging signal of every other B imaging signal Color tone correction means for generating a color tone correction signal from the signal interpolated in (1), or at least the bright portion also interpolates or R Surrounding R every other imaging signal Interpolation is performed by the average of the median value of the raw imaging signal and the center pixel imaging signal, and at least the bright portion is also interpolated by the weighted average of the median of the surrounding B pixel imaging signals and every other B imaging signal. An image pickup apparatus comprising: any one of color tone correction means for generating a color tone correction signal from a signal obtained by interpolating a B image pickup signal with a median value of every other peripheral B pixel image pickup signal. .

Further, the present invention provides an imaging apparatus having a solid-state imaging device,
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Or a means for processing a G video signal and a means for processing a video signal of an RB pixel having an interval twice as long as the interval between G pixels, or a means for transmitting a G video signal and an image of an RB pixel having an interval twice as long as the interval between G pixels Means for transmitting a signal, a means for halving the band of the R video signal and the B video signal with respect to the band of the G video signal,
The bright portion interpolates the R image signal with a weighted average of the median value of the peripheral R pixel image signal and the center pixel image signal (including the median value or the average of the median value and the central pixel). A noise which is a signal obtained by interpolating an image pickup signal with a weighted average of the median value of the surrounding B pixel image pickup signal and the center pixel image pickup signal (including the median value or the average of the median value and the center pixel) as a main line video signal An imaging apparatus comprising a reduction unit.

Further, the present invention provides an imaging apparatus having a solid-state imaging device,
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Or a means for processing a G video signal and a means for processing a video signal of an RB pixel having an interval twice as long as the interval between G pixels, or a means for transmitting a G video signal and an image of an RB pixel having an interval twice as long as the interval between G pixels Means for transmitting a signal, a means for halving the band of the R video signal and the B video signal with respect to the band of the G video signal,
The means for detecting (calculating) the color temperature, and the bright portion calculates the R image signal by a weighted average that is positively correlated with the detected (calculated) color temperature of the median value of the peripheral R pixel image signal and the center pixel image signal. The interpolation is performed, and the bright portion is obtained by weighting the B image signal with a weighted average that is negatively correlated with the detected (calculated) color temperature of the median value of the surrounding B pixel image signal and the center pixel image signal (the median value or the median value). A noise reduction unit that uses a signal interpolated by using the average of the median value and the central pixel) as a main line video signal;
The means for varying the amplification degree of the RGB video signal and the bright portion correlate the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (for small amplification degree, the central R When the image signal of the pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated), and the bright portion is obtained by interpolating the B image signal with the median value of the peripheral B pixel image signal and the central pixel. Interpolation by weighted average correlated with the amplification degree of the RGB video signal with the imaging signal (when the amplification degree is small, the imaging signal of the center R pixel is mainly, and when the amplification degree is large, the median value of the imaging signals of surrounding R pixels is mainly) An image pickup apparatus comprising: a noise reduction unit that converts the converted signal into a main line video signal.
An imaging apparatus comprising: means for halving the band of the R video signal and the band of the B video signal by half with respect to the band of the G video signal.

  According to the present invention, even in a linear matrix, even in 12-color masking in which a specific hue is detected for each pixel and a specific hue is corrected for each pixel, noisy B or R noise becomes And the decrease in the execution S / N is referred to as interpolation using the median value of the surrounding pixels, the average of the median value of the surrounding pixels and the center pixel, or the weighted average of the median value of the surrounding pixels and the center pixel. The hue is corrected by correcting the hue with the noise-reduced signal, and even if a video signal of R, B, RY, or BY is required to have a Y-equivalent band, so-called 4: 4: 4, in chroma key processing or the like, It is possible to realize both the maintenance of the color band of the main line signal, the improvement of the color tone correction, and the maintenance of the execution S / N.

FIG. 2 is a block diagram showing one embodiment of the television camera of the present invention. FIG. 2 is a block diagram showing one embodiment of the television camera of the present invention. FIG. 2 is a block diagram showing one embodiment of the television camera of the present invention. FIG. 2 is a block diagram showing one embodiment of the television camera of the present invention. FIG. 2 is a block diagram showing one embodiment of the television camera of the present invention. FIG. 4 is a schematic diagram illustrating a hue range corresponding to a magnitude relationship of R / G / B. FIG. 2 is a block diagram illustrating a configuration of a hue detection correction unit according to one embodiment of the present invention. FIG. 11 is a block diagram illustrating a configuration of a hue detection / correction unit according to another embodiment of the present invention. FIG. 2 is a block diagram illustrating a configuration of a hue detection correction unit according to one embodiment of the present invention. FIG. 4 is an explanatory diagram of a hue region in color tone correction according to one embodiment of the present invention. FIG. 3 is a conceptual diagram of a hue region according to one embodiment of the present invention. FIG. 4 is an explanatory diagram of a principle of calculating a primary color component, a complementary color component, and a saturation component according to an embodiment of the present invention. FIG. 4 is a block diagram illustrating a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process according to an embodiment of the present invention. FIG. 13 is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process according to another embodiment of the present invention. FIG. 13 is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process according to another embodiment of the present invention. FIG. 4 is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. FIG. 4 is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. FIG. 5 is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method to which an addition weight variable means is added according to an embodiment of the present invention. FIG. 4 is a correction characteristic diagram according to the embodiment of the present invention. FIG. 11 is a block diagram illustrating a configuration of a hue / saturation detection correction unit according to another embodiment of the present invention. FIG. 11 is a block diagram illustrating a configuration of a hue / saturation detection correction unit according to another embodiment of the present invention. FIG. 6 is a block diagram illustrating a configuration of a hue / saturation detection / correction unit according to another embodiment of the present invention. FIG. 14 is an explanatory diagram of a hue region in color tone correction according to another embodiment of the present invention. FIG. 10 is a conceptual diagram of a hue region according to another embodiment of the present invention. FIG. 11 is an explanatory diagram of a principle of calculating a primary color component and a complementary color component according to another embodiment of the present invention. FIG. 11 is a correction characteristic diagram according to another embodiment of the present invention. It is a schematic diagram which shows the operation | movement of the conventional 6-color independent color correction. FIG. 6 is a schematic diagram showing an operation on a color vector waveform of six color inside / outside independent tone correction according to one embodiment of the present invention. It is a schematic diagram which shows operation | movement on the color vector waveform of 12 colors inside / outside independent color tone correction of another Example of this invention. It is a schematic diagram which shows the operation | movement on the color vector waveform of 24 color inside / outside independent color tone correction of another Example of this invention. FIG. 7 is a schematic diagram showing an operation on a color vector waveform of six-color independent tone correction according to another embodiment of the present invention. It is a schematic diagram which shows operation | movement on the color vector waveform of 6 color independent tone correction corresponding to the saturation of 6 color points of the vector chart of another Example of this invention. It is a schematic diagram which shows operation | movement on the color vector waveform of 12 independent color tone correction | amendment corresponding to the saturation of 6 color points of the vector chart of another Example of this invention. It is a schematic diagram which shows the operation | movement on the color vector waveform of 6 color independent saturation continuous variable tone correction of another Example of this invention. It is a schematic diagram which shows the operation | movement on the color vector waveform of 12 colors independent saturation continuous variable tone correction of another Example of this invention. It is a schematic diagram which shows the operation | movement on the color vector waveform of 24 color saturation independent continuous variable tone correction of another Example of this invention. It is a schematic diagram which shows the operation | movement of the interpolation of the center pixel of one Example of this invention with a surrounding pixel median. It is a schematic diagram which shows the operation | movement of the interpolation of the center pixel of another Example of this invention with the average of a center pixel and a surrounding pixel. It is a schematic diagram which shows the interpolation operation | movement of the center pixel of another Example of this invention with the weighted average of the center pixel and the surrounding pixel of 1: 3. It is a schematic diagram which shows the operation | movement of interpolation of the center pixel of another Example of this invention with a 3: 1 weighted average of a center pixel and a surrounding pixel median.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Hereinafter, the independent color tone correction in which the color tone correction direction is changed according to the saturation will be described with reference to FIGS. 1A, 1B, and 2. FIG.
1A and 1B are block diagrams showing one embodiment of the television camera of the present invention.
1A is a pre-gamma matrix, and FIG. 1B is a post-gamma matrix.
Incident light from a subject is formed into an image by a lens unit 31, and the formed incident light is separated into red light, green light, and blue light by a prism (color separation optical system) unit 32 of the television camera 30. (Charge Coupled Device) 33R, 33G, 33B, 33G1, 33G2 + AFE (Analog Front End Processor) or a CMOS (Complementary Metal Oxide Semiconductor) image sensor performs photoelectric conversion. The photoelectrically converted R / G / B signals are subjected to correlated double sampling, gain correction, and analog-digital conversion internally by an AFE (analog front end processor) in a CCD and in a CMOS image sensor, thereby correcting hue and saturation detection. The video signal is sent to a video signal processing unit 35 having a function, and various video signal processes such as color tone correction, contour correction, gamma correction, and knee correction are performed.

After various kinds of video signal processing are performed in the digital signal processing unit 5,
Y = 0.2126R + 0.7152G + 0.0722B Pb = 0.5389 (BY) BT of Pr = 0.6350 (RY). R / G / B is converted into a luminance signal (Y) and a color difference signal (Pb / Pr) by the calculation formula 709 or the like. Then, it is converted into a serial video signal by the parallel-serial converter 7 and output to the outside. ITU / BT. Y and Pb / Pr may be converted by the calculation formula of 2020.

  A CPU (Central Processing Unit) 39 controls each unit of the television camera 1. Further, the image display unit 40 of the viewfinder or the monitor display displays a setting menu of the image pickup apparatus and an arbitrary hue / saturation area in the specific hue.

  Here, the hue / saturation detection / correction unit 38 in the video signal processing unit 35 with the hue / saturation detection / correction function shown in FIG. 3 of the block diagram showing the configuration of the hue / saturation detection / correction unit according to one embodiment of the present invention , R / G / B, the hue / saturation range of the color of the subject is detected from the magnitude relationship between the signal levels. FIG. 2 shows a hue range corresponding to the magnitude relationship of R / G / B. Here, the hue is displayed in six divisions. However, if the magnitude relationship between the R / G / B signal levels is further subdivided, twelve independent colors, sixteen independent colors, eighteen independent colors, twenty-four independent colors, etc. More hues can be redifferentiated.

  The CPU 9 passes information on an arbitrary hue range set by the user to the hue detection / correction unit 38 in the video signal processing unit 35 with the hue detection / correction function, and sends the information to the hue detection / correction unit in the video signal processing unit 35 with the hue detection / correction function. 38 passes to the CPU 9 the hue information of the pixel matching the hue range set by the user and the saturation information of the pixel. Based on the hue information of the pixel and the saturation information of the pixel, the CPU 9 controls the hue / saturation correction calculation in the video signal processing unit 35 having the hue / saturation detection / correction function, and independently adjusts the colors having different saturations. Correction and more accurate color gamut conversion can be realized with easy adjustment.

  In the viewfinder or monitor display 40, the menu screen is superimposed on the image of the subject, and the user sets the hue range, the saturation range, and the luminance signal level while watching the menu screen. In order to confirm whether the hue range set by the user matches the color of the target object, the hue range and the saturation range set in the viewfinder or the monitor display are superimposed on the subject image of 40. A marker may be displayed in the area of the matching position.

  As described above, the first color signal of the primary color point such as ITU / BT.2020 having a wider color gamut than the primary color point of BT.709 is converted into the second color signal having a different color gamut based on the primary color of BT.709. Convert and simply convert the third color signal of the primary color point based on the primary color point of BT.709 to the fourth color signal of the primary color point such as ITU / BT.2020 in a wider color gamut than the primary color point of BT.709. When converting to a signal and correcting it, the amount and direction of color tone correction can be varied by correlating with the saturation for each pixel, or the amount and direction of color tone correction can be changed independently inside and outside of saturation. By having an independent color tone correction function for six or more colors that varies the amount and direction of color tone correction depending on the degree, color gamut conversion with higher fidelity can be realized with easy adjustment.

Hereinafter, independent color tone correction in which the color tone correction direction is changed according to the saturation will be described with reference to FIGS. 3A to 8 and FIGS. 14 to 17C.
In FIG. 3A, first, color difference signals RG, RB, and GB are calculated from input video signals R, G, and B by subtracters 1, 2, and 3, and the result is used as a hue area determination circuit. 4 and a chroma component amount, a primary color component amount, and a complementary color component amount determination circuit 5 to determine the chroma component amount, the primary color component amount, and the complementary color component amount.
Therefore, based on the operation results of the subtracters 1, 2, and 3, the hue region determination circuit 4 first determines the hue region as shown in FIG. FIG. 5 is a conceptual diagram of the hue region, in which a straight line extending from the center point in each color direction is used as a reference line, thereby dividing the hue region into six hue regions.

The saturation component amount, primary color component amount, and complementary color component amount determination circuit 5 compares the levels of the signals R, G, and B, and determines the maximum level, intermediate level, and minimum level as shown in FIG. Then, in the course of the comparison judgment, the level difference between the maximum level and the intermediate level is obtained, and this is used as the primary color component amount. Further, the level difference between the intermediate level and the minimum level is obtained, and this is used as the complementary color component amount. The level difference between the maximum level and the minimum level is obtained, and this is defined as the saturation component amount. Here, the maximum level color corresponds to the primary color, and the minimum level component corresponds to the white component. Then, the complementary color can be determined from the information of the maximum level color and the minimum level color. As a result, as shown in FIG. 4, the primary color component and the complementary color component can be determined.
That is, the color tone correction of the color tone correction in which the direction is continuously variable with the saturation shown in FIG. 17 of a schematic diagram showing the operation on the color vector waveform of the six-color independent color saturation continuously variable color correction of another embodiment of the present invention is realized. FIG. 3A is a block diagram illustrating a detailed configuration of the hue detection / correction unit according to the embodiment of the present invention.

In the example of FIG. 6, since the maximum level is R and the intermediate level is G, the primary color component is R and the complementary color component is Ye (yellow) which is an intermediate hue between R and G. The primary color component amount is RGB, the complementary color component amount is GB, and the minimum level B amount is the white component amount. Therefore, in the case of FIG. 8, the result shown in the second from the bottom in FIG. 4 is obtained. RB is the saturation component amount.
The determination result of the hue region by the determination circuit 4 is supplied to a constant selection circuit 6, a specific gain constant is selected according to the determination result, and is supplied to the multipliers 7 and 8, so that the saturation component amount and The correction is performed by multiplying the primary color component amount and the complementary color component amount determined by the primary color component amount and the complementary color component amount determination circuit 5, respectively. For this reason, a specific gain constant corresponding to each of the hue regions from region 1 to region 6 is set in the constant selection circuit 6 in advance.
The primary color component amount and the complementary color component amount multiplied by the gain constants by the multipliers 7 and 8 are added to a data selection / addition circuit 11 for selecting addition / subtraction and selecting connection for video signals R, G, and B. , Respectively, and on the other hand via complementers (-1 multipliers) 9, 10. Then, after an addition destination is selected by the data selection and addition circuit 11, the data is supplied to each of the adders 12, 13, and 14, and is added to the video signals R, G, and B.
The determination may be made after all the color differences have been calculated, and the coefficient may be calculated. Alternatively, the color difference may be calculated while making the determination, and the order does not matter.

Therefore, when performing color tone correction of the signal R, for example, in the case of correction in the saturation direction, the primary color component amount RG is multiplied by a specific constant Kr and then added to the video signal R. At this time, if the ratio based on the constant Kr is in the range of -1 to 1 times, even with this correction, the level difference between the intermediate level and the minimum level (complementary color component amount) and the minimum level amount (white component amount) are obtained. It does not change.
When correcting the signal Ye in the saturation direction, the complementary color component amount GB is multiplied by a specific constant Ky and then added to R and G, respectively. Also at this time, if the ratio based on the constant Ky is in the range of -1 to 1 times, even with this correction, the level difference between the maximum level and the intermediate level (primary color component amount) and the minimum level amount (white component amount) Does not change.

Therefore, in this case, by operating the constants Kr and Ky, it is possible to independently correct the saturation direction of the primary color R and the complementary color Ye while maintaining the white balance. In the above-described six-color independent tone correction method, the correction in the chromaticity direction can be similarly performed independently, and the independent correction can be similarly performed even when the input video signal is in another hue. Is omitted.
Further, in the present invention, the saturation of the difference between the primary color (maximum value) and white (minimum value) after the maximum value and minimum value determination is calculated, and a coefficient is calculated according to the saturation.
As shown in FIG. 17A, FIG. 17A, and FIG. 16A, the calculation of the coefficient according to the saturation is a linear change.
As shown in FIG. 15D, selecting a coefficient according to the saturation is a step change.

FIG. 14 is a schematic diagram showing the operation of the conventional six-color independent tone correction, and FIG. 15A is a schematic diagram showing the operation on the color vector waveform of the six-color inside / outside independent tone correction of one embodiment of the present invention. FIG. 16A is a schematic diagram showing an operation on a color vector waveform of 6-color internal / external independent tone correction according to another embodiment of the present invention. FIG. 17A is a schematic diagram showing an operation on a color vector waveform of six-color independent saturation continuous variable tone correction according to another embodiment of the present invention.
FIGS. 15A, 16A and 17A are schematic diagrams showing the operation on the color vector waveform of the 6-color inside / outside independent tone correction of one embodiment of the present invention. Since the holding of the hue and saturation around the white portion at the center can be adjusted independently, the degree of freedom of color tone correction at the time of color gamut conversion is increased.

As shown in FIG. 16A of a schematic diagram showing the operation on the color vector waveform of the six-color inside / outside independent tone correction of another embodiment of the present invention, the correlation with the inside / outside saturation is calculated by the saturation of the six color points of the vector chart. It is possible to change the hue saturation around the pure color around the color gamut and retain the hue saturation around the white at the center of the color gamut in the color tone correction when converting between the wide color gamut and the narrow color gamut. The degree of freedom is increased because the adjustment can be made more naturally.
FIG. 3B is a block diagram illustrating a configuration of a hue detection / correction unit according to another embodiment of the present invention. FIG. 3B is a diagram showing details of realizing a tone correction in different directions between the inside and outside of FIG. 15A and a tone correction in which the correlation between the inside and outside saturation of FIG. 16A is changed corresponding to the saturation of six color points of the vector chart. FIG. 3 is a block diagram showing a configuration.
FIG. 3B is different from FIG. 3A in that the constant selection circuit 24 is changed. By the constant selection circuit 24, the color tone correction in a stepwise different direction between the inside and the outside of FIG. 15D and the correlation with the inside and outside saturation of FIG. 16A are varied in accordance with the saturation of the six color points of the vector chart. And realize.

In the stepwise variable operation according to the saturation, if the constant selection circuit 24 is installed as shown in FIG. 3B of a block diagram showing a detailed configuration for realizing color tone correction in different directions stepwise inside and outside of FIG. 15D. good.
In the stepwise variable operation according to the saturation, as in the processing of the saturation coefficient in FIG. 7D which is the operation of the constant selection circuit 24 in FIG. 3B, the color difference is calculated and the maximum value and the minimum value are determined. A coefficient may be selected according to the saturation, and the saturation coefficient may be varied stepwise according to the saturation.
The coefficient is calculated according to the saturation, but the curve change will be described later.

That is, the first color signal of a primary color point such as ITU / BT.2020 having a wider color gamut than the primary color point of BT.709 is converted into a second color signal having a different color gamut based on the primary color of BT.709, In addition, simply, the third color signal of the primary color point based on the primary color point of BT.709 is converted into the fourth color signal of the primary color point of ITU / BT.2020 etc. having a wider color gamut than the primary color point of BT.709. When making corrections, the amount and direction of color tone correction can be varied by correlating the saturation for each pixel, or the amount and direction of color tone correction can be varied independently inside and outside of saturation, and so on. By having an independent color tone correction function for six or more colors that can change the amount and direction of correction, more accurate color gamut conversion can be realized with easy adjustment.
In particular, it is better to change the correlation to the saturation inside and outside according to the saturation of the six color points of the vector chart, in the color tone correction at the time of conversion between the wide color gamut and the narrow color gamut, around the pure color around the color gamut. Since the adjustment of the conversion of the hue and saturation and the maintenance of the hue and saturation around white in the center of the color gamut can be adjusted more naturally, the degree of freedom is increased.

Hereinafter, a device for detecting and correcting color tones such as 12 independent colors and 24 independent colors will be described in detail with reference to the illustrated embodiment.
First, FIGS. 9A, 9B and 9C show an embodiment of the present invention, in which 15 is an intermediate hue setting circuit, 17 is an α / β and β / α calculation circuit, 18 is a constant selection circuit, 19, 20, and 26. Is a multiplier, 21 is a data selection addition / subtraction circuit, and the rest is the same as the technique shown in FIG.
FIG. 9A is a block diagram of an embodiment in which the amount and direction of tone correction are linearly correlated with the saturation such as the independent 12 colors in FIG. 17B and the independent 24 colors in FIG. 17C, and FIG. FIG. 17C is a block diagram of an embodiment in which the amount and direction of color tone correction are correlated to the power of saturation such as 24 independent colors in FIG. 17C, and FIG. 9C shows the inside and outside of 12 independent colors in FIG. 15B and 24 independent colors in FIG. It is a block diagram of an embodiment of color tone correction of variable direction.
FIG. 15B is a schematic diagram showing the operation on the color vector waveform of the 12-color internal / external independent tone correction of another embodiment of the present invention, and FIG. 15C is the 24-color internal / external independent tone of another embodiment of the present invention. It is a schematic diagram which shows the operation | movement on the color vector waveform of correction.

The intermediate color / hue setting circuit 15 functions to enable setting of an intermediate color to be newly set as a reference color. For example, a skin color (hue F) which is an intermediate color between R and Ye is set in advance. The primary color / complementary color area determination circuit 16 determines the hues of the input video signals R, G, and B based on the data from the hue area determination circuit 4 and the hue F provided from the intermediate hue setting circuit 15, and determines a predetermined hue. It serves to generate a control signal S.
The α / β and β / α calculating circuit 17 has a function of calculating predetermined constants α / β and β / α based on the data supplied from the intermediate hue setting circuit 15. The constants α / β and β / α will be described later. The constant selection circuit 18 functions to select and output one of the constants α / β and β / α according to the control signal S.

  The multipliers 19, 20, and 26 convert the saturation component, the primary color component amount, and the saturation component, the primary color component, and the complementary color component output from the complementary color component amount determination circuit 5 into the constant α selected by the constant selection circuit 18. / Β and β / α. The data selection addition / subtraction circuit 21 selects data according to the result of determination by the hue region determination circuit 4 and the control signal S, and performs predetermined addition / subtraction. The details of the operation of this circuit will be described later.

Next, the operation of this embodiment will be described. FIGS. 10 and 11 are diagrams illustrating saturation (color saturation) and chromaticity (hue) for explaining the operation principle of the present invention. In these figures, the direction away from the origin O is the saturation and saturation. The direction perpendicular to the degree (the direction in which the circle is drawn) represents the chromaticity.
Here, the present invention is applicable to any intermediate color correction such as an inner and outer independent tone correction function of more than six colors such as skin color independent, 12 colors independent, 16 colors independent, 18 colors independent, or 24 colors independent in addition to 6 colors independent. Can be applied, but it is considered that it is often applied particularly to correction of skin color. Therefore, in this embodiment, a description will be given below mainly of correction of skin color as an example. Then, since the hue of this flesh color is located in a region between R and Ye, that is, region 6, these FIGS. 10 and 11 show only region 6 from R (red) to Ye (yellow), Is represented by a point F.
Therefore, this point is set as the auxiliary reference color F as shown in the figure, and the data is set in the intermediate color hue setting circuit 15 as described above.

As a result, the area 6 is divided into two auxiliary areas, that is, the area (1) and the area (2), by an axis passing from the center point O to the auxiliary reference color F point, that is, an auxiliary reference line. . Next, the hue of the input video signal is divided by the primary color / complementary color area determination circuit 16 into an area (1) between R and F and an area (2) between F and Ye as shown in FIG. Is determined. Then, in this case, first, since the operation is performed when the determination result of the hue region determination circuit 4 is the region 6, the primary color component amount and the complementary color component amount output from the calculation circuit 5 are respectively It is as follows.
Primary color component amount = RG = Rc, complementary color component amount = GB = Yc

Next, whether the hue of the input video signal is in the region (1) or the region (2) is identified by the judgment of the primary color / complementary color region judgment circuit 16 and separately as shown below. The correction is made.
<Correction processing in region (1)> At this time, the output from each circuit is as follows. First, the constant selection circuit 18 selects a constant β / α, and outputs the constant β / α to the multipliers 19 and 20. Next, the data selection addition / subtraction circuit 21 outputs a signal [Rc−Yc × (β / α)], a signal (−Yc), and a signal [Yc × (β / α)]. Further, constants Kr and Kf are selected by the constant selection circuit 6, and these constants Kr and Kf are output to the multipliers 7 and 8.

  As a result, the data selection / addition circuit 11 first outputs the signal [Rc−Yc × (β / α)] × Kr + Kf × [Yc × (β / α)] to the adder 12 and outputs the signal R Then, the signal [(−Yc) × Kf] is output to the adder 14 and added to the signal B.

Therefore, in FIG. 10, when the point A is set as the coordinates of the input video signal and is represented by a vector A, the vector A is represented by a combination of the R component vector R1 and the flesh color component vector F1.
A = R1 + F1 Next, assuming that the gain constant exclusively for adjusting the saturation direction of R is Kr and the gain constant exclusively for adjusting the saturation direction of skin color is Kf, when performing color tone correction in the saturation direction of R, | It suffices to add R1 | × Kr in the saturation direction of R, that is, add it to R. To perform color tone correction in the skin color saturation direction, it is sufficient to add | F1 | × Kf in the skin color saturation direction. .

  A method of calculating these quantities | R1 | and | F1 | and a method of adding them in the skin color saturation direction will be described. To this end, all corrections can be expressed as corrections to the R, G, and B components. Good. Therefore, first, the R component basic vector is R, the flesh color basic vector is F, the Ye component basic vector is Y, and the B component basic vector is B. F = α × Y + β × R = α × (−B) + β × R And

  Next, the coordinate vector A of the input video signal is represented by combining the R component and the Ye component. Here, A = Y × Yc + R × Rc, and Rc and Yc can be easily obtained as described in the conventional color tone correction method. In this case, R> G> B, so that Rc = RG and Yc = GB, as is apparent from FIG.

  Then, A = Y × Yc + R × Rc = (1 / α) × (F−β × R) × Yc + R × Rc = F × Yc / α + R × (Rc−β × Yc / α), and | R1 | = Rc-β × Yc / α | F1 | = Yc / α.

  Therefore, if F × Yc / α is represented by vector R and vector B, F × Yc / α = (α × (−B) + β × R) × Yc / α = B × (−Yc) + R × (β × Yc / α).

  Therefore, the above results are summarized as follows. That is, first, | R1 | Kr = (Rc−β × Yc / α) × Kr may be added to R to perform color tone correction in the saturation direction of R. Next, in order to perform color tone correction in the skin color saturation direction, it is only necessary to add | F1 | × Kf in the skin color saturation direction. This means that −Yc × Kf is added to B, and (β × Yc / α) × Kf is equivalent to adding R to R.

Here, assuming that the angle between the R vector and the flesh color vector is θ, α / Sin (60 ° −θ) = β × Sin (θ), so β / α = Sin (60 ° −θ) / Sin (θ).
Therefore, when θ = 20 °, β / α = 1.8794, but when this is set to ≒ 2.0, the correction at this time is (Rc− 2 × Yc) × Kr may be added to R. For color tone correction in the skin color saturation direction, −Yc × Kf may be added to B, and 2 × Yc × Kf may be added to R. By changing β / α, the reference axis of the flesh color can be adjusted.
The above is the description of the correction in the saturation direction. However, the same concept can be applied to the correction in the chromaticity direction, and a description thereof will be omitted.

<Correction processing in region (2)> At this time, the output from each circuit is as follows. First, a constant α / β is selected by the constant selection circuit 18, and the constant α / β is output to the multipliers 19 and 20. Next, the data selection addition / subtraction circuit 21 outputs a signal [Yc−Rc × (α / β)], a signal (Rc), and a signal [−Rc × (α / β)]. Further, constants Ky and Kf are selected in the constant selection circuit 6, and these constants Ky and Kf are output to the multipliers 7 and 8.
As a result, the data selection / addition circuit 11 first outputs the signal [Rc × Kf] to the adder 12 and adds it to the signal R. Then, the signal − [Yc−Rc × (α / β) )] × Ky−Kf × [Rc × (α / β)] is output to the adder 14 and added to the signal B.

Therefore, in FIG. 3, when the point C is set as the coordinates of the input video signal and is represented by a vector C, this vector C is represented by a combination of the Ye component vector Y1 and the skin color component vector F2.
C = Y1 + F2 Next, assuming that the gain constant exclusively for adjusting the saturation direction of Ye is Ky and the gain constant exclusively for adjusting the saturation direction of flesh color is Kf, | Y1 | × Ky may be subtracted from B, and | F2 | × Kf may be added in the skin color saturation direction for color tone correction in the skin color saturation direction.

Next, the method of calculating | Y1 | and | F2 | and the method of addition in the flesh color saturation direction are the same as those in the above-described region (1), and are as follows.
C = Y × Yc + R × Rc = Y × Yc + (1 / β) × (F−α × Y) × Rc = F × Rc / β + Y × (Yc−α × Rc / β)
Therefore, | Y1 | = Yc−α × Rc / β | F2 | = Rc / β.
Here, if F × Rc / β is represented by vector R and vector B, F × Rc / β = (α × (−B) + β × R) × Rc / β = −B × (α × Rc / β) + R × Rc.

Therefore, the above results are summarized as follows. That is, first, when performing color tone correction in the saturation direction of Ye, | Y1 | × Ky = (Yc−α × Rc / β) × Ky may be subtracted from B.
Next, when performing color tone correction in the skin color saturation direction, | F2 | × Kf is added in the skin color saturation direction, which means that (−α × Rc / β) × Kf is changed to B. It is equivalent to adding Rc × Kf to R.

Therefore, if the angle θ between the R vector and the flesh color vector is set to 20 ° as in the above-described region (1), α / β = 0.5321. Therefore, when this is set to ≒ 0.5, When the color tone correction in the saturation direction of Ye is performed, (Yc−0.5Rc) × Ky may be subtracted from B. When the color tone correction in the saturation direction of the skin color is performed, −0.5 × Rc × Kf may be added to B, and Rc × Kf may be added to R.
The above is the description of the correction in the saturation direction. However, the same concept can be applied to the correction in the chromaticity direction, and a description thereof will be omitted.

FIG. 4 shows characteristics obtained by the correction described in each of the above-mentioned areas (1) and (2). The characteristics shown in FIG. 4 are obtained by superimposing the respective gain characteristics of the color tone correction in the saturation direction of R, the color tone correction in the saturation direction of Ye, and the color tone correction in the saturation direction of the skin color. In addition, if the skin color saturation direction gain constant Kf is controlled, the color tone correction in the skin color saturation direction can be performed regardless of the saturation direction gain constant Kr of R and the gain constant Ky in the saturation direction of Ye. I understand.
Therefore, according to this embodiment, the effect on R and Ye can be suppressed to a minimum, effective color tone correction can be performed for flesh color, and uncomfortable feeling when switching the television camera can be surely obtained. Can be eliminated.

  Next, FIG. 5 shows a correction characteristic according to another embodiment of the present invention. In this embodiment, a correction function having a gain characteristic centered on the flesh color axis F is generated and extracted. . This is added to the conventional function in the embodiment of FIG. 5, and according to this method, the correction can be made in such a manner as to compensate for the area that cannot be corrected by the conventional method.

Further, in the present invention, the saturation of the difference between the primary color (maximum value) and white (minimum value) after the maximum value and minimum value determination is calculated, and a coefficient is calculated according to the saturation.
The calculation of the coefficient according to the saturation is a linear change.
Selecting a coefficient according to the saturation is a step change.
That is, in addition to six independent colors, independent color tone correction of more than six colors such as skin color independent, 12 color independent, 16 color independent, 18 color independent, 24 color independent, etc., and the direction and amount of color tone correction corresponding to saturation. Is to adjust the conversion of the hue and saturation around the pure color around the gamut and the preservation of the hue and saturation around the white at the center of the gamut in the tone correction when converting between the wide gamut and the narrow gamut. Can be adjusted more naturally, thereby increasing the degree of freedom.

A description will be given with reference to FIG. 9B of a block diagram showing a configuration of a hue / saturation detection / correction unit according to another embodiment of the present invention.
FIG. 9B is a block diagram showing a configuration of a hue / saturation detection / correction unit according to another embodiment of the present invention. Multipliers 21, 22, and 23 are added to FIG. 9A. In FIG. 9B, the saturation component is raised to the power and applied to the data selection addition / subtraction circuit 21 in order to cope with a curve-variable operation based on the saturation. In FIG. 9B, there are three multipliers 21, 22, and 23, which are the cubes of the saturation components. However, the number of multipliers (not shown) may be two squares, and the number of multipliers (not shown) may be two fourths. .

FIG. 7C is an explanatory diagram of a color tone correction process according to the six-color inside / outside independent color tone correction method according to another embodiment of the present invention, and the amount and direction of the color tone correction are correlated with the power of saturation. The difference from FIG. 7A is that a process for raising the selected saturation component to the power of n natural numbers has been added. In FIG. 9B, multipliers for n natural numbers in FIG. 7C are added.
By changing the direction of saturation and changing the hue, the hue saturation around the pure color around the color gamut and the hue around the white at the center of the color gamut can be corrected. Since the adjustment with the holding can be adjusted more naturally, the degree of freedom is increased.

  FIGS. 17A, 17B, and 17C show an operation in which color saturation is continuously variable in the color tone correction in a direction variable, and FIGS. 15A to 15C show operations in which a threshold is set in the saturation. FIG. 15D shows the variation in the step response of the color tone correction in the direction variable with the saturation. The operation is not limited to the color tone correction operation in which the direction is variable by the linear correlation with the saturation. The operation may be a stepwise variable operation based on the saturation or a curved operation variable depending on the saturation.

  FIG. 7E of the explanatory diagram of the color tone correction processing by the six color inside / outside independent color tone correction method corresponding to the color saturation of the six color points and six colors corresponding to the color saturation of the six color points of the vector chart of another embodiment of the present invention. FIG. 16A is a schematic diagram showing the operation on the color vector waveform of the independent tone correction, and FIG. 16A is a schematic diagram showing the operation on the color vector waveform of the 12 independent color correction corresponding to the saturation of the six color points of the vector chart of another embodiment of the present invention. FIG. 16B is a schematic diagram showing the operation, FIG. 9A is a block diagram showing the configuration of a hue / saturation detection / correction unit according to one embodiment of the present invention, and the configuration of the hue / saturation detection / correction unit according to another embodiment of the present invention. The color tone correction processing by the six color inside / outside independent color tone correction method corresponding to the saturation of the six color points will be described with reference to 9C of the block diagram showing FIG.

  FIG. 16A is a schematic diagram showing an operation on a color vector waveform of six-color independent tone correction corresponding to the saturation of a color point of a vector chart according to another embodiment of the present invention, and FIG. FIG. 10 is a schematic diagram showing an operation on a color vector waveform of 12-color independent tone correction corresponding to the saturation of 6 color points of the vector chart of one embodiment of the present invention. Corresponding to the saturation of the six color points of G, B, Cy, Ye, and Mg, the saturation in pixel units such as varying the correlation between the inside and outside saturation or varying the threshold inside and outside saturation for each pixel. The operation on the color vector waveform of the independent color tone correction function for six or more colors, in which the influence method of the saturation that varies the amount and direction of the color tone correction, is shown. Corresponding to the saturation of the six color points of the vector chart, the conversion of the hue saturation around the pure color around the color gamut and the white around the center of the color gamut in the color tone correction at the time of conversion between the wide color gamut and the narrow color gamut. The degree of freedom can be increased because the adjustment with the hue / saturation can be adjusted more naturally.

In FIGS. 16A and 16B, the thresholds inside and outside the saturation are varied in accordance with the saturations of the six color points in the vector chart, but the correlation between the inside and outside saturations may be varied for each pixel.
Although FIG. 16A and FIG. 16B show the six color points of the vector chart in a fixed manner, corresponding to the movement of the six color points of the vector chart at the time of conversion between the wide color gamut and the narrow color gamut, the inside and outside of the saturation are changed. May be varied, or the correlation between the inside and outside saturation may be varied for each pixel.
In the color tone correction processing using the six color inside / outside independent color tone correction method according to one embodiment of the present invention, the color tone is adjusted to the saturation corresponding to the saturation of the six color points R, G, B, Cy, Ye, and Mg in the vector chart. The coefficient of linear correlation between the amount and direction of correction changes depending on hue.

In the block diagram of FIG. 3A or FIG. 3B, FIG. 9A, FIG. 9B, or FIG. 9C, showing the configuration of the hue detection / correction unit according to the embodiment of the present invention, the hue of the hue area determination of 4, The coefficient of the linear correlation between the amount and direction of the color tone correction changes to the saturation.
By changing the direction of saturation and changing the hue, the hue saturation around the pure color around the color gamut and the hue around the white at the center of the color gamut can be corrected. Since the adjustment with the holding can be adjusted more naturally, the degree of freedom is increased.
In the above embodiment, the hue range is limited to R and Ye. However, it is needless to say that the present invention can be applied to any hue, and the type and number of the reference colors are also different. Needless to say, it can be set arbitrarily.
The limitation of the hue range to R and Ye is an operation of tone correction of skin color independent in addition to independent of inside and outside of six colors, and is not limited to an operation of tone correction of skin color in addition to independent of inside and outside of six colors, but also 12 color saturation independent tone correction. Alternatively, an operation of 16-color internal / external independent color correction, an operation of 18-color internal / external independent color correction, or an operation of 24-color internal / external independent color correction may be used.

  In other words, independent color tone correction of more than six colors such as skin color independent, 12 color independent, 16 color independent, 18 color independent, 24 color independent, etc., in addition to 6 colors independent, and the correlation with the inner and outer chromas is represented by 6 in the vector chart. It is better to change in accordance with the saturation of the color point in the hue correction at the time of conversion between the wide color gamut and the narrow color gamut, to convert the hue saturation around the pure color around the color gamut and the white around the center of the color gamut. The degree of freedom is increased because the adjustment with the hue / saturation can be adjusted more naturally.

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1A, 1B, 3C, 7A, 7B, 7C, 7D, 7E, 7F, 18A, and 18B. I do.
1A and 1B are block diagrams showing one embodiment of the television camera of the present invention. 1A is a pre-gamma matrix, and FIG. 1B is a post-gamma matrix. FIG. 3C is a block diagram showing a configuration of a hue detection and correction unit according to an embodiment of the present invention, and is a block diagram showing a detailed configuration for realizing color temperature detection and color tone correction of six-color independent color tone correction. As one embodiment of the present invention, color temperature detection (calculation) is added to FIGS. 1A and 1B. The color temperature detection (calculation) includes a gate unit 41, an excessive signal deletion unit 42, and a peak detection unit 43 shown at the left end of FIG. 3C.

In FIGS. 1A and 1B, the R / G / B signal subjected to photoelectric conversion is subjected to gain correction by an AFE (analog front end processor) in a CCD, and is internally corrected in a CMOS image pickup device. This is a means for varying the degree of amplification of the video signal.
FIG. 7A is a block diagram showing a detailed configuration for calculating and interpolating the median of eight pixels around the color tone correction processing according to an embodiment of the present invention. The B image signal is interpolated into the peripheral B pixel median value to obtain a B video signal for color tone correction, the central pixel image signal of the B image signal is maintained, and the average of the median value of the peripheral B pixel image signal and the central pixel image signal is calculated. Switching to the median value of the surrounding B pixel image pickup signal to obtain a main line B video signal.

  FIG. 7B is a block diagram showing a detailed configuration for calculating and interpolating the median value of eight pixels around the color tone correction processing according to another embodiment of the present invention. The G imaging signal is maintained at the center pixel imaging signal and used as a video signal for color tone correction, the center pixel imaging signal of the G imaging signal is maintained, the median of the surrounding G pixel imaging signals, the average of the center pixel imaging signals, and the surrounding G pixels Switching to the median value of the imaging signal to obtain a G video signal for the main line. It is common with variable in color temperature.

  FIG. 7C is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process according to another embodiment of the present invention. The R image signal is interpolated by the average of the median value of the peripheral R pixel image signal and the center pixel image signal to obtain an R image signal for color tone correction, the center image signal of the R image signal is maintained, and the R image signal of the surrounding R pixel image signal is maintained. The average value of the center value and the center pixel image pickup signal and the center value of the surrounding R pixel image pickup signal are switched to obtain an R image signal for the main line.

FIG. 7D is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. .
The B image signal for color tone correction is obtained by interpolating the B image signal with the weighted averaging of the median value of the peripheral B pixel image signals and the center pixel image signal based on the B amplification degree including the reciprocal of the calculated screen color temperature. Signal. Maintain the center pixel image signal of the B image signal, maintain the center pixel, switch the weighted average of the median value of the peripheral B pixel image signal and the central pixel image signal to the median value of the peripheral B pixel image signal, It is assumed to be a B pixel video signal. The weighted average is correlated with the B amplification degree including the reciprocal of the calculated screen color temperature.

FIG. 7E is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. .
Based on the calculated R amplification including the color temperature of the screen, the R pixel video signal for color tone correction is interpolated by the weighted average of the median value of the surrounding R pixels and the central pixel. The R image signal is interpolated by weighted averaging of the median value of the peripheral R pixel image signal and the center pixel image signal to obtain an R pixel image signal for color tone correction. Maintaining the center pixel imaging signal of the R imaging signal, maintaining the center pixel, switching between the weighted averaging of the median value of the surrounding R pixel imaging signal and the center pixel imaging signal, and switching to the center value of the surrounding R pixel imaging signal, Let it be an R pixel video signal. The weighted average is correlated with the R amplification including the calculated color temperature of the screen.

FIG. 7F is a block diagram showing a detailed configuration for calculating and interpolating the median value of eight pixels around the color tone correction processing by the correction method to which the addition weight variable means is added according to the embodiment of the present invention.
According to the G amplification degree, the G video signal for color tone correction is interpolated by weighted averaging of the median value of the peripheral G pixels and the central pixel. The G image signal is interpolated by weighted averaging of the median value of the peripheral G pixel image signal and the center pixel image signal to obtain an R pixel image signal for color tone correction. Maintain the center pixel image signal of the G image signal, maintain the center pixel, switch the weighted average of the median value of the peripheral G pixel image signal and the central pixel image signal to the median value of the peripheral G pixel image signal, It is assumed to be a G pixel video signal. The weighted average is correlated with the G amplification degree.

7A to 7E, reference numeral 9 denotes a surrounding pixel signal selection unit, 16 denotes interpolation of surrounding pixels of white defects, 18 denotes interpolation of surrounding pixels of black defects, and 19 denotes a peripheral pixel median value detecting unit, 21 and 21. Reference numerals 22, 23, 24, 25, 26, 27, 28 denote comparators, and reference numeral 29 denotes a video signal switch.
7A, 7B, 7C, 7D, 7E, and 7F, reference numerals 5 and 6 denote line memories, 7 denotes a video signal switch, and 8 denotes a delay unit. The line memories 5 and 6 generate a 1H2H image signal from the 0H image signal, and generate 1H and 2H white defect interpolation signals from the 0H white defect interpolation signal. The video signal switch 7 selects the image signals of 0H, 1H, and 2H to generate peripheral pixel signals of the image signals, and selects the white defect interpolation signals of 0H, 1H, and 2H to select the peripheral pixels of the white defect interpolation signal. Generate a signal. Instead of the line memories 5 and 6, a frame memory (not shown) may be used.

7A to 7E, the delay unit 8 delays the imaging signal by the delay of the surrounding pixel median value detection unit 19 and delays the white spot interpolation signal. Then, the surrounding pixel median value detection unit detects the surrounding pixel median value of the imaging signal or the white flaw interpolation signal from the surrounding pixel signal of the imaging signal using the comparators 21 to 28, and uses the comparator 21 to detect the surrounding pixel median of the white flaw interpolation signal. In steps 21 to 28, the median value of the peripheral pixels of the white defect interpolation signal is detected.
Then, in accordance with the video signal timing (address) of the white flaw and the video signal timing (address) of the white flaw at the time of determining the white flaw level or less from the white flaw interpolation determination 15 at the time of standard imaging, pixels surrounding the white flaw are determined. The interpolation unit 29 interpolates the imaging signal to one of the median value of the surrounding pixels of the imaging signal, the average of the median pixel and the median value of the surrounding pixels, and the weighted average of the median value of the pixel and the median pixel. The main line video signal.
In addition, Y: RY: BY in Non-Patent Document 1 has a visual characteristic color band of 3: 1: 0.7 = 4.3: 1.4: 1. Even if interpolation is performed on the average of the central pixel and the median value of the surrounding pixels, and B is interpolated on the median value of the surrounding pixels, it is not noticeable in visual characteristics. When the main line video signal is used for the chroma key, if only the color tone correction signal is interpolated without interpolating the main line video signal, the noise increase due to the color tone correction is not noticeable.

  FIG. 18A is a schematic diagram showing the operation of interpolating the central pixel with the median value of surrounding pixels according to the embodiment of the present invention, and is effective when the numerical value is largely different due to the noise of the median value. FIG. 18B is a schematic diagram showing the operation of interpolation of the center pixel of another embodiment of the present invention by averaging the center pixel and the center value of surrounding pixels. It is effective when it is. If 16384 of 14bit is 800%, 4096 of 12bit becomes 200%, 1024 of 10bit becomes 50%, and 256 of 8bit becomes 12.5%.

In FIG. 18A, the imaging signal 1024 of the 200% central pixel is interpolated by the median 4096 of the surrounding normal pixel imaging signals 4096, 4300, 3800, 3900, 4000, 4200, 4100, 8192. The imaging signal 2048 of the 50% central pixel is interpolated by the median value 1024 of the surrounding normal pixel imaging signals 1024, 1000, 996, 1090, 1000, 1048, 1100, 998. The image signal 1024 of the 12.5% central pixel is interpolated by the median value 256 of the surrounding normal pixel image signals 256, 260, 200, 240, 270, 300, 248 and 220.
In FIG. 18B,
The average of 200% of the central pixel and the peripheral pixel median is (3328 + 4096) ÷ 2 = 3712,
The average of 50% of the central pixel and the peripheral pixel median is (1280 + 1024) / 2 = 1152,
The average of 12.5% of the central pixel and the peripheral pixel median is (448 + 256) / 2 = 352.

Depending on the type of the solid-state imaging device, noise is inversely proportional to the sensitivity and proportional to the amplification in order to increase the amplification by the lower sensitivity. Therefore, if the color tone correction signal is generated from the signal interpolated by the weighted average correlated with the amplification degree, the noise reduction effect is large without reducing the color band of the video signal of the main line.
Further, if the signal interpolated by the weighted average correlated with the amplification degree is used as the video signal of the main line, the noise reduction effect is greater. However, if the interpolated signal is a main line video signal, the color band is also reduced, so that the execution sensitivity is prioritized over color reproduction.

That is, one embodiment of the present invention has an image pickup apparatus having a solid-state image pickup device, and has means for performing signal processing on RGB signals from three RGB plates and a color separation optical system.
The Y: RY: BY of Non-Patent Document 1 converts the R image signal of both the dark part and the bright part according to the visual characteristic color band of 3: 1: 0.7 = 4.3: 1.4: 1. Interpolation or weighted average of the median value of every other surrounding R pixel image signal and the center pixel image signal or R image signal is calculated by averaging the median value of every other surrounding R pixel image signal and the center pixel image signal. Interpolation, at least the bright portion also interpolates or weights the B image signal every other B pixel image signal with the median value of the center value and the center pixel image signal of every other B image signal. It has color tone correction means for generating a color tone correction signal from the signal interpolated by the median value, or means for varying the amplification degree of the RGB video signal. Correlation with the amplification between the median value of the signal and the center pixel imaging signal (for small amplification, imaging of the center R pixel When the signal is main and the amplification degree is large, the median value of the imaging signals of the surrounding R pixels is mainly calculated). And at least the bright portion correlates with the median value of every other peripheral B pixel imaging signal and the amplification degree of the central pixel imaging signal in every other B imaging signal. When the amplification degree is large, the median value of the imaging signals of the surrounding B pixels is mainly used). A color tone correction signal is obtained from a signal obtained by interpolating with a weighted average or interpolating the B imaging signal with the median value of every other surrounding B pixel imaging signals. An image pickup apparatus comprising any one of color tone correcting means for generating color tone.

In the above imaging apparatus,
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Or a means for processing the G video signal and a means for processing the video signal of the RB pixel having an interval twice as long as the interval of the G pixel, and a means for halving the band between the R video signal and the B video signal with respect to the G video signal. The R image signal is interpolated by the average of the median value and the center pixel image signal of every other peripheral R pixel image signal of every Y pixel, and the B image signal of the every other peripheral B pixel image signal of every Y pixel. An image pickup apparatus comprising any one of color tone correction means for generating a color tone correction signal from a signal interpolated by a median value.

As described above, according to the present invention, even in a linear matrix, even in 12-color masking in which a specific hue is detected for each pixel and a specific hue is corrected for each pixel, when a tone correction is performed, B The fact that noise is mixed in other colors and the execution S / N is reduced is determined by the median value of the peripheral pixel image signal or the average of the median value of the peripheral pixel image signal and the central pixel image signal or the center of the peripheral pixel image signal. It is prevented by correcting the hue with a noise-reduced signal called interpolation using a weighted average of the value and the center pixel imaging signal, and the R, B, RY, and BY video signals are equivalent to Y in chroma key processing and the like. Even if a bandwidth of 4: 4: 4 is required, it is possible to realize both the maintenance of the color band of the main line signal, the improvement of the color tone correction, and the maintenance of the execution S / N.
In particular, if the R image signal is interpolated by the average of the median value of the peripheral R pixel image signal and the central pixel image signal, and the B image signal is interpolated by the median value of the peripheral B pixel image signal, the color band of color tone correction is also Y: RY: BY of Patent Document 1 can be approximated to a visual characteristic color band of 3: 1: 0.7 = 4.3: 1.4: 1.

Further, according to the present invention, in the above imaging device,
Means for processing the G video signal and means for processing the video signal of the RB pixel at an interval twice the interval of the G pixel, or means for transmitting the G video signal and the video signal of the RB pixel at an interval twice the interval of the G pixel Transmitting at least one of:
Means for varying the amplification degree of the RGB video signal, and at least the bright portion correlates the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (the center is smaller when the amplification degree is small). When the image signal of the R pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated. A weighted average correlated with the amplification degree of the RGB video signal with the imaging signal of the central pixel (the imaging signal of the central R pixel is mainly used when the amplification degree is small, and the median value of the imaging signals of surrounding R pixels is mainly used when the amplification degree is large). And a color tone correction means for generating a color tone correction signal from the signal interpolated in step (1).
In other words, the invention prioritizes the maintenance of the execution S / N in maintaining both the color band maintenance of the main signal and the improvement of the color tone correction and the maintenance of the execution S / N.
In particular, if the R image signal is interpolated by the average of the median value of the peripheral R pixel image signal and the central pixel image signal, and the B image signal is interpolated by the median value of the peripheral B pixel image signal, the color band of the main line signal is also non-interpolated. Y: RY: BY of Patent Document 1 can be approximated to a visual characteristic color band of 3: 1: 0.7 = 4.3: 1.4: 1.

Further, the present invention provides an imaging apparatus having a solid-state imaging device,
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Alternatively, the bandwidth of the R video signal and the bandwidth of the B video signal are reduced by half with respect to the bandwidth of the G video signal, such as a means for processing the G video signal and a means for processing the video signal of the RB pixel at an interval twice the interval between the G pixels. Having means,
Means for varying the degree of amplification of the RGB video signal; and a bright portion for calculating the weighted average of the R image signal between the median value of the peripheral R pixel image signal and the center pixel image signal (the median value or the average value of the median value and the center pixel). Interpolation is performed by using the average, and the bright part is obtained by weighting the B image signal between the median value of the peripheral B pixel image signal and the center pixel image signal (including the median value or the average of the median value and the center pixel). An image pickup apparatus comprising a noise reduction unit that uses a signal interpolated in step (1) as a main line video signal.

Further, the present invention provides an imaging apparatus having a solid-state imaging device,
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Or a means for processing a G video signal and a means for processing a video signal of an RB pixel having an interval twice as long as the interval between G pixels, or a means for transmitting a G video signal and an image of an RB pixel having an interval twice as long as the interval between G pixels Means for transmitting a signal, a means for halving the band of the R video signal and the B video signal with respect to the band of the G video signal,
The means for varying the amplification degree of the RGB video signal and the bright portion correlate the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (for small amplification degree, the central R When the image signal of the pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated. Interpolation by weighted average correlated with the amplification degree of the RGB video signal with the imaging signal (when the amplification degree is small, the imaging signal of the center R pixel is mainly, and when the amplification degree is large, the median value of the imaging signals of surrounding R pixels is mainly) An imaging apparatus comprising: a noise reduction unit configured to convert the converted signal into a main line video signal.
In other words, the invention prioritizes maintaining the effective S / N over maintaining the color band of the main signal. This invention is suitable for news gathering and surveillance applications.
Further, if the R image signal is interpolated by the average of the median value of the peripheral R pixel image signal and the central pixel image signal, and the B image signal is interpolated by the median value of the peripheral B pixel image signal, the color band of the main line signal is also non-interpolated. Y: RY: BY of Patent Document 1 can be approximated to a visual characteristic color band of 3: 1: 0.7 = 4.3: 1.4: 1.

(Embodiment 2) Interpolation by weighted averaging of color temperature detection, amplification degree, median value of surrounding pixels, and center pixel Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1A, 1B, 1C, 1D, and 1E. 3C, FIG. 7B, FIG. 7D, FIG. 7E, FIG. 7F, FIG. 18C, and FIG. 18D, focusing on differences from the first embodiment.
1A and 1B are block diagrams showing one embodiment of the television camera of the present invention. 1A is a pre-gamma matrix, and FIG. 1B is a post-gamma matrix. FIG. 3C is a block diagram showing a configuration of a hue detection and correction unit according to an embodiment of the present invention, and is a block diagram showing a detailed configuration for realizing color temperature detection and color tone correction of six-color independent color tone correction.
As one embodiment of the present invention, color temperature detection is added to FIGS. 1A and 1B.
The color temperature detection includes a gate section 41, an excessive signal deletion section 42, and a peak detection section 43 shown at the left end of FIG. 3C.

In FIG. 1A, FIG. 1B, FIG. 1C, FIG. 1D, and FIG. 1E, the gain of the photoelectrically converted R / G / B signal is corrected by an AFE (analog front end processor) in a CCD, and the internal , Which is a means for varying the amplification degree of the RGB video signal.
1A and 1B, the prism (color separation optical system) 32 and the image pickup devices 33R, 33G, 33B are similar to the prism (color separation optical system) 32 and the image pickup devices 33R, 33G, 33G2, 33B as shown in FIG. 1C. Alternatively, four-plate image sensors R, G1, G2, and B may be used.
Further, as shown in FIG. 1D, a single plate of an image pickup element 47 with an on-chip color filter having a Bayer arrangement of R, G1, G2, and B may be used.

1C, 1D, and 1E are block diagrams showing one embodiment of the television camera of the present invention. In addition, color temperature detection is added to FIGS. 1C, 1D, and 1E.
FIG. 1C shows a pre-gamma matrix of a camera using a four-chip image sensor of R, G1, G2, and B and a color separation optical system. It has means for processing signals. FIG. 1D is a single-chip camera of an image pickup device with an on-chip color filter having a Bayer array, and a matrix after gamma. The image pickup device with an on-chip color filter having a Bayer array of R, G1, G2, and B and means for processing signals thereof. Have. FIG. 1E shows a pre-gamma matrix of a camera using an RGB three-plate image sensor and a color separation optical system.

  Further, in FIGS. 1C and 1D, means for transmitting (so-called DG transmission) RG1G2B and four colors for each color or R- (G1 + G2), G1, G2, B- (G1 + G2) or R- (Y1 + Y2), Y1, Y2, B- (Y1 + Y2) or R-G1, G1, G2, B-G2 or R-Y1, Y1, Y2, B-Y2 or R-G2, G1, G2, B-G1 or R-Y2, Y1, There are means for transmitting two main signals, such as Y2 and B-Y1, such as a signal having a main luminance and a signal having a main color. That is, although the details will be described in the third embodiment, FIGS. 1C and 1D have a unit for reducing the band or luminance of the R video signal and the B video signal by half with respect to the band of the G video signal.

  In FIG. 1C and FIG. 1D, a G video signal, every other B video signal, and every other R video signal are converted and processed by the 34 parallel-serial conversion units. After the signal processing, means for transmitting (so-called DG transmission) for each of the four colors of R, G1, G2, and B by 44 serial-to-parallel conversion units with matrices or R- (G1 + G2), G1, G2, B- ( G1 + G2) or R- (Y1 + Y2), Y1, Y2, B- (Y1 + Y2) or R-G1, G1, G2, B-G2 or R-Y1, Y1, Y2, B-Y2 or R-G2, G1, G2 , BG1, or RY2, Y1, Y2, BY1, etc., are converted into a main signal of luminance and a main signal of color and transmitted. The transmitted video signal is converted to a G video signal, every other B video signal, and every other R video signal by the matrix-to-parallel-to-serial conversion unit 45, and subjected to signal processing.

  FIG. 1E is a block diagram (matrix after gamma) showing an embodiment of the television camera of the present invention, in which (R− (G1 + G2), G1, G2, B− (G1 + G2) or R− (Y1 + Y2), Y1). , Y2, B- (Y1 + Y2) or R-G1, G1, G2, B-G2 or R-Y1, Y1, Y2, B-Y2 or R-G2, G1, G2, B-G1 or R-Y2, Y1 , Y2, and B-Y1, etc., are transmitted as a main signal of luminance and a main signal of color.

FIG. 7B is a block diagram showing a detailed configuration for calculating and interpolating the median value of eight pixels around the color tone correction processing according to another embodiment of the present invention.
The G imaging signal is maintained at the center pixel imaging signal and used as a video signal for color tone correction, the center pixel imaging signal of the G imaging signal is maintained, the median of the surrounding G pixel imaging signals, the average of the center pixel imaging signals, and the surrounding G pixels Switching to the median value of the imaging signal to obtain a G video signal for the main line. It is common with variable in color temperature.

FIG. 7D is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. .
The B image signal is interpolated by weighted averaging of the median value of the peripheral B pixel image signals and the center pixel image signal to obtain a B pixel video signal for color tone correction. Maintain the center pixel image signal of the B image signal, maintain the center pixel, switch the weighted average of the median value of the peripheral B pixel image signal and the central pixel image signal to the median value of the peripheral B pixel image signal, It is assumed to be a B pixel video signal. The weighted average is correlated with the B amplification degree including the reciprocal of the calculated screen color temperature.

FIG. 7E is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. The R pixel video signal for color tone correction is interpolated by weighted averaging of the median of the surrounding R pixels and the central pixel.
The R image signal is interpolated by weighted averaging of the median value of the peripheral R pixel image signal and the center pixel image signal to obtain an R pixel image signal for color tone correction. Maintaining the center pixel imaging signal of the R imaging signal, maintaining the center pixel, switching between the weighted averaging of the median value of the surrounding R pixel imaging signal and the center pixel imaging signal, and switching to the center value of the surrounding R pixel imaging signal, Let it be an R pixel video signal. The weighted average is correlated with the R amplification including the calculated color temperature of the screen.

FIG. 7F is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method to which an addition weight variable means is added according to an embodiment of the present invention, and a G image for color tone correction. The signal is interpolated by the weighted average of the median value of the surrounding G pixels and the central pixel.
The G image signal is interpolated by weighted averaging of the median value of the peripheral G pixel image signal and the center pixel image signal to obtain an R pixel image signal for color tone correction. Maintain the center pixel image signal of the G image signal, maintain the center pixel, switch the weighted average of the median value of the peripheral G pixel image signal and the central pixel image signal to the median value of the peripheral G pixel image signal, It is assumed to be a G pixel video signal. The weighted average is correlated with the G amplification degree.

FIG. 18C is a schematic diagram showing the operation of interpolation of the center pixel by another weighted average of 1: 3 between the center pixel and the center value of the surrounding pixels according to another embodiment of the present invention. This is effective when the values are slightly different.
FIG. 18D is a schematic diagram showing the operation of interpolation of the center pixel of another embodiment of the present invention by a weighted average of 3: 1 between the center pixel and the center value of the surrounding pixels. This is effective when the numerical values are slightly different.
If 16384 of 14bit is 800%, 4096 of 12bit becomes 200%, 1024 of 10bit becomes 50%, and 256 of 8bit becomes 12.5%.

In FIG. 18C,
The average of 1: 3 between the 200% central pixel and the peripheral pixel median is (1280 × 1 + 4096 × 3) ÷ 4 = 3392,
The average of 50% of the central pixel and the peripheral pixel median is (1920 × 1 + 1024 × 3) ÷ 4 = 1248,
The average of 12.5% of the central pixel and the peripheral pixel median is (512 × 1 + 256 × 3) ÷ 2 = 320.

In FIG. 18D,
The 3: 1 average of the 200% central pixel and the peripheral pixel median is (3700 × 3 + 4096 × 1) ÷ 4 = 3799,
The average of 50% of the central pixel and the peripheral pixel median is (1150 × 3 + 1024 × 1) ÷ 4 = 1118.5 ≒ 1119,
The average of 12.5% of the central pixel and the peripheral pixel median is (372 × 3 + 256 × 1) × 2 = 343.

That is, another embodiment of the present invention relates to an imaging device having a solid-state imaging device,
An image sensor with a color filter of Bayer array of R, G1, G2, and B and means for processing signals thereof, or a four-chip image sensor of RG1G2B, a color separation optical system, and means for processing signals thereof, and at least a bright portion Also, the R image signal is interpolated by a weighted average of the median value of the peripheral R pixel image signal and the center pixel image signal or the R image signal is interpolated by the average of the median value of the peripheral R pixel image signal and the center pixel image signal, At least the bright portion also interpolates the B image signal with a weighted average of the median value of the peripheral B pixel image signal and the central pixel image signal or the color tone correction signal from the signal obtained by interpolating the B image signal with the median value of the peripheral B pixel image signal. Having color tone correction means for generating;
Means for signal processing of RGB signals from the three RGB plates and the color separation optical system, and at least the bright portion is provided with a median value and a central pixel image signal of the surrounding R pixel image signals every other R image signal. Interpolation by weighted average or interpolation of R imaging signals by the average of the median value of center R imaging signals and the center pixel imaging signal of every other surrounding R pixel, and at least the bright part also captures every other B imaging signal of surrounding B pixel. Having a tone correction means for generating a tone correction signal from a signal obtained by interpolating with a weighted average of the median value of the signal and the center pixel image signal or interpolating the B image signal with the median value of every other surrounding B pixel image signal When,
An image pickup apparatus comprising any one of the video signal processing means and the color tone correction means.

Another embodiment of the present invention relates to an image pickup device with a color filter having a Bayer array of R, G1, G2, and B, and a means for processing signals thereof, or a four-plate image pickup device of R, G1, G2, and B. A color separation optical system and a unit for processing the signal, or a unit for processing the G video signal and a unit for processing the video signal of the RB pixel having an interval twice as large as the interval of the G pixel. Means for halving the band between the video signal and the B video signal,
At least the bright portion also interpolates the R image signal with a weighted average (including only the median value) of the median value of the peripheral R pixel image signal and the central pixel image signal, and at least the bright portion also converts the B image signal into the surrounding B pixel image signal. An image pickup apparatus characterized by having a color tone correcting means for generating a color tone correction signal from a signal interpolated by a weighted average (including only the median value) of the median value of the central pixel and the central pixel image pickup signal.

  Further, another embodiment of the present invention relates to an image pickup device with a color filter of a Bayer array of R, G1, G2, and B, and a means for processing signals thereof, or a four-plate image pickup device of RG1G2B, a color separation optical system, and a color separation optical system. R video signal and B video signal for the band of the G video signal, such as a means for processing a signal, a means for processing a G video signal, and a means for processing a video signal of an RB pixel having an interval twice as long as the interval between G pixels. And a means for halving the band of the R image signal. The R image signal is interpolated by the average of the median value and the center pixel image signal of every other R pixel image signal of every other Y pixel, and the B image signal is extracted by one Y pixel. An image pickup apparatus comprising any one of a color tone correction unit and a color tone correction unit that generates a color tone correction signal from a signal interpolated by a median value of the image signals of other surrounding B pixels.

  As described above, according to the present invention, even in a linear matrix, even in 12-color masking in which a specific hue is detected for each pixel and a specific hue is corrected for each pixel, when a tone correction is performed, B The fact that noise is also mixed in other colors and the execution S / N is reduced means that the median value of the surrounding pixels or the average of the median value of the surrounding pixels and the center pixel or the weighting of the median value of the surrounding pixels and the center pixel. The hue is corrected by correcting the hue with a noise-reduced signal, which is averaged by interpolation, and R, B, RY, and BY video signals require a band equivalent to Y, so-called 4: 4: 4, in chroma key processing and the like. Even so, it is possible to realize both the maintenance of the color band of the main line signal, the improvement of the color tone correction, and the maintenance of the execution S / N.

Here, a method of detecting (calculating) the color temperature will be described.
In FIG. 3C, the white balance adjustment adjusts the gain of each color video signal or adjusts the sensitivity of the image sensor so that the video signals of red R, green G, and blue B become 1: 1: 1 when capturing a white object. Adjustments have been made. A white balance detection circuit shown at the left end of FIG. 3C is used. A high-luminance portion of a video signal is extracted by a gate unit 41, and an excessive-level high-luminance portion such as illumination or the sun is deleted by an excessive signal deletion unit 42. , The peak detection unit 43 detects the peak values Rp, Gp, and Bp of the red R, green G, and blue B video signals, and adjusts the gains of the red and blue signals so that the peak values of the video signals are equal. Is used.

Based on the gain control values of the red and blue signals obtained by performing the white balance adjustment, the color temperature of the subject is calculated (detected) by the following sixth-order approximation formula.
Y = (0.0000005 * X ⁶ -0.000002 * X ⁵ -0.00006 * X ⁴ + 0.0006 * X ³
+ 0.0096 * X ² −0.1445 * X + 3.1848) * 1000 Note that X is a gain difference between red and blue = (Rg−Bg) dB.

According to another embodiment of the present invention, color tone correction is performed from a signal obtained by interpolating an RB image signal with a weighted average correlated to a color temperature, using the color temperature of the subject calculated (detected) by the above sixth-order approximation formula. Generate a signal.
At a low color temperature of about 3200K, the sensitivity of the R image signal is about the same as the sensitivity of the G image signal, and the sensitivity of the B image signal is half of the sensitivity of the G image signal, although it depends on the type of solid-state image sensor. The noise is inversely proportional to the sensitivity because the sensitivity is low, the noise of the R image signal is about the same as the noise of the G image signal, and the noise of the B image signal is the noise of the G image signal. More than double the noise. At a medium color temperature of about 5600K, the sensitivity of the R and B imaging signals is slightly lower than the sensitivity of the G imaging signal, and the noise of the R and B imaging signals is slightly higher than the noise of the G imaging signal. At a high color temperature of about 10000K, the sensitivity of the R image signal is less than half the sensitivity of the G image signal, the sensitivity of the B image signal is about the same as the sensitivity of the G image signal, The noise is at least twice the noise of the G image signal, and the noise of the B image signal is substantially equal to the noise of the G image signal.
Therefore, if a color tone correction signal is generated from a signal interpolated with a weighted average correlated with the color temperature and with the amplification degree, the noise reduction effect is large.

That is, another embodiment of the present invention relates to an imaging apparatus having a solid-state imaging device,
Means for processing the G video signal and means for processing the video signal of the RB pixel at an interval twice the interval of the G pixel, or means for transmitting the G video signal and the video signal of the RB pixel at an interval twice the interval of the G pixel Transmitting at least one of:
The means for varying the amplification degree of the RGB video signal and the bright portion correlate the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (for small amplification degree, the central R When the image signal of the pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated), and the bright portion is obtained by interpolating the B image signal with the median value of the peripheral B pixel image signal and the central pixel. Interpolation by weighted average correlated with the amplification degree of the RGB video signal with the imaging signal (when the amplification degree is small, the imaging signal of the center R pixel is mainly, and when the amplification degree is large, the median value of the imaging signals of surrounding R pixels is mainly) Color tone correction means for generating a color tone correction signal from the resulting signal,
A means for detecting (calculating) a color temperature, and a weighted average of at least a bright portion of the R image signal which is positively correlated with the detected (calculated) color temperature of the median value of the peripheral R pixel image signal and the center pixel image signal. At least in the bright portion, color correction from a signal obtained by interpolating the B image signal with a weighted average negatively correlated with the detected (calculated) color temperature of the median value of the peripheral B pixel image signal and the center pixel image signal. An image pickup apparatus including a color tone correction unit that generates a signal.

As described above, according to another embodiment of the present invention, the R imaging signal is positively correlated with the detected (calculated) color temperature of the median value of the surrounding R pixel imaging signal and the center pixel imaging signal, and the amplification degree The weighted average is negatively correlated with the detected (calculated) color temperature of the median value of the peripheral B pixel image signal and the center pixel image signal, and is correlated with the amplification degree. By generating a color tone correction signal from the signal interpolated in step (1), it is possible to reduce noise of a color having a high amplification degree and a large amount of noise from being mixed into other colors, thereby improving color tone correction and improving execution S / N. Maintenance can be better balanced.
In particular, this is effective when G has high sensitivity under low illuminance shooting conditions and the G video signal is also noisy. This is an invention in which maintenance of the execution S / N is prioritized over maintenance of the color band of the color tone correction. This is an invention suitable for news coverage.

Further, the present invention provides an imaging apparatus having a solid-state imaging device,
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Alternatively, the bandwidth of the R video signal and the bandwidth of the B video signal are reduced by half with respect to the bandwidth of the G video signal, such as a means for processing the G video signal and a means for processing the video signal of the RB pixel at an interval twice the interval between the G pixels. Having means,
The means for varying the amplification degree of the RGB video signal and the bright portion correlate the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (for small amplification degree, the central R When the image signal of the pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated. Interpolation by weighted average correlated with the amplification degree of the RGB video signal with the imaging signal (when the amplification degree is small, the imaging signal of the center R pixel is mainly, and when the amplification degree is large, the median value of the imaging signals of surrounding R pixels is mainly) Noise reduction means for making the main signal a video signal,
The means for detecting (calculating) the color temperature, and the bright portion calculates the R image signal by a weighted average that is positively correlated with the detected (calculated) color temperature of the median value of the peripheral R pixel image signal and the center pixel image signal. The interpolation is performed, and the bright portion is obtained by weighting the B image signal with a weighted average that is negatively correlated with the detected (calculated) color temperature of the median value of the surrounding B pixel image signal and the center pixel image signal (the median value or the median value). An image pickup apparatus comprising: a noise reduction unit that uses a signal interpolated by using the average of the median value and the center pixel as a video signal of a main line.
In particular, this is effective when G has high sensitivity under low illuminance shooting conditions and the G video signal is also noisy. In other words, the invention prioritizes maintaining the effective S / N over maintaining the color band of the main signal. This is an invention suitable for monitoring use.

(Embodiment 3) Transmission of two systems with a main signal of luminance and a main signal of color Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1C, 1D, 1E, 3C, 7A, 7B and 7B. 7C, FIG. 7D, FIG. 7E, and FIG. 7F, description will be made focusing on differences between the first embodiment and the second embodiment.
The prism 32 and the imaging devices 33R, 33G, and 33B in FIGS. 1A, 1B, and 1E may be four-plate imaging devices, such as the prism 32 and the imaging devices 33R, 33G, 33G2, and 33B, as shown in FIG. 1C. Further, as shown in FIG. 1D, an image pickup device 47 with an on-chip color filter having a Bayer array of R, G1, G2, and B may be used.

In FIG. 1C, FIG. 1D, and FIG. 1E, the gain of the photoelectrically converted R / G / B signal is corrected by an AFE (analog front end processor) in a CCD, and the gain is corrected internally in a CMOS image sensor. This is a means for varying the amplification degree of the RGB video signal.
1C, 1D, and 1E are block diagrams showing one embodiment of the television camera of the present invention. FIG. 1C shows a pre-gamma matrix, and FIG. 1D shows a post-gamma matrix.
Further, as one embodiment of the present invention, color temperature detection is added to FIGS. 1C and 1D.

  In FIG. 1C and FIG. 1D, means for transmitting RG1G2B and each color of four systems (so-called DG transmission), or R- (G1 + G2) for R color difference, B- (G1 + G2) for B color difference, or R for R color difference. -(Y1 + Y2), Y1, Y2, B- (Y1 + Y2) of B color difference or R-G1, G1, G2 of R color difference, BG2 of B color difference, or R-Y1, Y1, Y2, B color difference of R color difference Signals and colors are mainly luminance signals of two systems such as B-Y2 or R-G2, G1, G2, B-G1 of B color difference or R-Y2, Y1, Y2 of R color difference, and B-Y1 of B color difference. And means for transmitting the signal.

  In FIG. 1C and FIG. 1D, the parallel-serial converter 34 converts the signal into a G image signal, every other B image signal, and every other R image signal, and performs signal processing. After the signal processing, the serial-to-parallel conversion unit with matrices 44 transmits the RG1G2B and the four colors (so-called DG transmission) for each color or R-color difference R- (G1 + G2), G1, G2, and B color difference B- (G1 + G2). ) Or R-color difference R- (Y1 + Y2), Y1, Y2, B-color difference B- (Y1 + Y2) or R-color difference R-G1, G1, G2, B-color difference BG2 or R-color difference R-Y1, Y1 , Y2, B-Y2 for B color difference or R-G2, G1, G2 for R color difference, BG1 for B color difference or RY2, Y1, Y2 for R color difference, and B-Y1 for B color difference. The signal is converted into a main signal of luminance and a main signal of color, and transmitted. The transmitted video signal is converted to a G video signal, every other B video signal, and every other R video signal by the matrix-to-parallel-to-serial conversion unit 45, and subjected to signal processing.

  FIG. 1E is a block diagram (matrix after gamma) showing an embodiment of the television camera of the present invention, in which R-color difference R- (G1 + G2), G1, G2, B color difference B- (G1 + G2) or R color difference. R- (Y1 + Y2), Y1, Y2, B-color difference B- (Y1 + Y2) or R color difference R-G1, G1, G2, B color difference BG2 or R color difference R-Y1, Y1, Y2, B There are two main types of luminance, such as color difference BY2 or R color difference RG2, G1, G2, B color difference BG1 or R color difference RY2, Y1, Y2, B color difference BY1. The signal and the color are transmitted by the main signal.

FIG. 3C is a block diagram showing a configuration of a hue detection and correction unit according to an embodiment of the present invention, and is a block diagram showing a detailed configuration for realizing color temperature detection and color tone correction of six-color independent color tone correction.
The color temperature detection includes a gate section 41, an excessive signal deletion section 42, and a peak detection section 43 shown at the left end of FIG. 3C.

FIG. 7B is a block diagram showing a detailed configuration for calculating and interpolating the median value of eight pixels around the color tone correction processing according to another embodiment of the present invention.
The G imaging signal is maintained at the center pixel imaging signal and used as a video signal for color tone correction, the center pixel imaging signal of the G imaging signal is maintained, the median of the surrounding G pixel imaging signals, the average of the center pixel imaging signals, and the surrounding G pixels Switching to the median value of the imaging signal to obtain a G video signal for the main line. It is common with variable in color temperature.

FIG. 7D is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. .
The B image signal is interpolated by weighted averaging of the median value of the peripheral B pixel image signals and the center pixel image signal to obtain a B pixel video signal for color tone correction. Maintain the center pixel image signal of the B image signal, maintain the center pixel, switch the weighted average of the median value of the peripheral B pixel image signal and the central pixel image signal to the median value of the peripheral B pixel image signal, It is assumed to be a B pixel video signal. The weighted average is correlated with the B amplification degree including the reciprocal of the calculated screen color temperature.

FIG. 7E is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method in which a color temperature detection unit and an addition weight variable unit are added according to an embodiment of the present invention. The R pixel video signal for color tone correction is interpolated by weighted averaging of the median of the surrounding R pixels and the central pixel.
The R image signal is interpolated by weighted averaging of the median value of the peripheral R pixel image signal and the center pixel image signal to obtain an R pixel image signal for color tone correction. Maintaining the center pixel imaging signal of the R imaging signal, maintaining the center pixel, switching between the weighted averaging of the median value of the surrounding R pixel imaging signal and the center pixel imaging signal, and switching to the center value of the surrounding R pixel imaging signal, Let it be an R pixel video signal. The weighted average is correlated with the R amplification including the calculated color temperature of the screen.

FIG. 7F is a block diagram showing a detailed configuration for calculating and interpolating a median value of eight pixels around a color tone correction process by a correction method to which an addition weight variable means is added according to an embodiment of the present invention, and a G image for color tone correction. The signal is interpolated by the weighted average of the median value of the surrounding G pixels and the central pixel.
The G image signal is interpolated by weighted averaging of the median value of the peripheral G pixel image signal and the center pixel image signal to obtain an R pixel image signal for color tone correction. Maintain the center pixel image signal of the G image signal, maintain the center pixel, switch the weighted average of the median value of the peripheral G pixel image signal and the central pixel image signal to the median value of the peripheral G pixel image signal, It is assumed to be a G pixel video signal. The weighted average is correlated with the G amplification degree.

In other words, one embodiment of the present invention is based on the following principle: (a R, G1, G2, B image sensor signal with a color filter in a Bayer array or a video signal from the four plates R, G1, G2, B and the color separation optical system) Signal processing means, and at least the bright portion is interpolated with the weighted average of the median value and the center pixel image signal of the surrounding R color difference pixel image signal or the R color difference image signal of the surrounding R color difference pixel image Interpolation is performed by the average of the median value of the signal and the center pixel image signal, and at least the bright portion is interpolated by the weighted average of the median value of the surrounding B color difference pixel image signal and the center pixel image signal or the B color difference image is obtained. A color tone correction unit that generates a color tone correction signal from a signal obtained by interpolating the signal with the median value of the surrounding B color difference pixel imaging signal,
R, G1, G2, B means for transmitting each color of four systems (so-called DG transmission), or R- (G1 + G2) for R color difference, B- (G1 + G2) for G1, G2, B color difference or R- for R color difference (Y1 + Y2), Y1, Y2, B- (Y1 + Y2) of B color difference or R-G1, G1, G2 of R color difference, BG2 of B color difference, or R-Y1, Y1, Y2, R color difference B of B color difference The main signal and color are luminance of two systems such as -Y2 or R-color difference RG2, G1, G2, B-color difference BG1 or R-color difference RY2, Y1, Y2, B-color difference BY-1. Has means for transmitting the main signal and the main signal.

As described above, according to the present invention, even in a linear matrix, even in 12-color masking in which a specific hue is detected for each pixel and a specific hue is corrected for each pixel, when a tone correction is performed, B The fact that noise is also mixed in other colors and the execution S / N is reduced means that the median value of the surrounding pixels or the average of the median value of the surrounding pixels and the center pixel or the weighting of the median value of the surrounding pixels and the center pixel. The hue is corrected by correcting the hue with a noise-reduced signal, which is averaged by interpolation, and R, B, RY, and BY video signals require a band equivalent to Y, so-called 4: 4: 4, in chroma key processing and the like. Even so, it is possible to realize both the maintenance of the color band of the main line signal, the improvement of the color tone correction, and the maintenance of the execution S / N.
In particular, if the R image signal is interpolated by the average of the median value of the peripheral R pixel image signal and the central pixel image signal, and the B image signal is interpolated by the median value of the peripheral B pixel image signal, the color band of the color tone correction can be viewed. The characteristic color band can be approximated.

  Further, the R image signal is interpolated by a weighted average that is positively correlated with the detected color temperature of the center value of the surrounding R pixel image signal and the center value of the center pixel image signal, and the B image signal is calculated as the median value of the surrounding B pixel image signal. By generating a color tone correction signal from a signal interpolated by a weighted average negatively correlated with the detected color temperature of the center pixel imaging signal and the center pixel imaging signal, noise of a color having a high amplification degree and a large amount of noise is reduced to another color. The mixing can be reduced, and the improvement of the color tone correction and the maintenance of the execution S / N can be better balanced.

  Further, the R image signal is interpolated by a weighted average that is positively correlated with the detected color temperature of the median value of the peripheral R pixel image signal and the central pixel image signal, and the B image signal is median of the peripheral B pixel image signal. By generating a color tone correction signal from a signal interpolated by a weighted average negatively correlated with the detected color temperature of the center pixel imaging signal and the center pixel imaging signal, noise of a color having a high amplification degree and a large amount of noise is reduced to another color. The mixing can be reduced, and the improvement of the color tone correction and the maintenance of the execution S / N can be better balanced.

  4: 4: 4 full-band RGB signal processing and 4: 4: 4 of down-conversion from an image sensor signal with an on-chip color filter having a Bayer array of R, G1, G2, and B pixels having more than twice the number of pixels both vertically and horizontally. In full band transmission or RGB signal processing of 4: 4: 4 full band from RGB three plates and color separation optical system and transmission of 4: 4: 4 full band, pixel enlargement display of display and signal system May cause a side effect of band reduction of color tone correction. Therefore, the present invention is suitable for news coverage in which maintenance of the execution S / N is prioritized over maintenance of the color band of color tone correction.

  However, means for transmitting (so-called DG transmission) for each of the four colors of R, G1, G2, and B, or R- (G1 + G2) for R color difference, B- (G1 + G2) for G1, G2, B color difference, or R-color difference. R- (Y1 + Y2), Y1, Y2, B- (Y1 + Y2) of B color difference or R-G1, G1, G2 of R color difference, BG2 of B color difference or R-Y1, Y1, Y2, B color difference of R color difference The main signal is the luminance of two systems, such as B-Y2 or R-color difference R-G2, G1, G2, B-color difference B-G1 or R-color difference R-Y2, Y1, Y2, B-color difference BY-1. In the case of transmitting the main color and the main signal, the side effect of the band reduction of the color tone correction hardly appears even by the enlarged display of the pixel of the display or the up-conversion of the signal system.

  In other words, according to another embodiment of the present invention, means for transmitting (so-called DG transmission) for each of the four colors R, G1, G2, and B, or R- (G1 + G2), G1, G2, B-color difference B- (G1 + G2) or R color difference R- (Y1 + Y2), Y1, Y2, B color difference B- (Y1 + Y2) or R color difference R-G1, G1, G2, B-color difference BG2 or R R-Y1, Y1, Y2 of color difference, B-Y2 of B color difference or R-G2, G1, G2 of R color difference, B-G1 of B color difference or R-Y2, Y1, Y2 of R color difference, B of B color difference -By transmitting two main signals, such as Y1 and the like, of a main signal and a main signal of color, the side effect of the band reduction of the color tone correction by generating the color tone correction signal from the signal interpolated by the weighted average is more significant. The improvement of the color tone correction and the maintenance of the effective S / N. It is possible to stand.

Further, the present invention provides an imaging device having a solid-state imaging device,
Means for transmitting the G video signal and means for transmitting the RB pixel video signal having an interval twice as long as the interval of the G pixel, and halving the bandwidth of the R video signal and the B video signal with respect to the bandwidth of the G video signal Has,
The bright portion interpolates the R image signal with a weighted average of the median value of the peripheral R pixel image signal and the center pixel image signal (including the median value or the average of the median value and the central pixel). A noise which is a signal obtained by interpolating an image pickup signal with a weighted average of the median value of the surrounding B pixel image pickup signal and the center pixel image pickup signal (including the median value or the average of the median value and the center pixel) as a main line video signal An imaging apparatus comprising a reduction unit.

  In particular, this is effective when G has high sensitivity under low illuminance shooting conditions and the G video signal is also noisy. In other words, the invention prioritizes maintaining the effective S / N over maintaining the color band of the main signal. This is an invention suitable for monitoring use.

  The image pickup apparatus according to the embodiment of the present invention can perform a noisy B or R by performing a color tone correction on a linear matrix or a 12-color masking for detecting a specific hue for each pixel and correcting a specific hue for each pixel. Noise is mixed in other colors, and the execution S / N is reduced. The median value of the peripheral pixels or the average of the median value of the peripheral pixels and the central pixel, or the weight of the median value of the peripheral pixels and the central pixel. This is prevented by correcting the hue with a noise-reduced signal called interpolation and averaging, and in chroma key processing or the like, the video signal of R, B, RY, and BY has a band equivalent to Y, that is, a so-called 4: 4: 4. Even if requested, it is possible to realize both the maintenance of the color band of the main signal, the improvement of the color tone correction, and the maintenance of the execution S / N.

  As described above, one embodiment of the present invention has been described in detail. However, the present invention is not limited to the above-described embodiment, and can be implemented with various modifications without departing from the spirit of the present invention. This application claims the benefit of priority based on Japanese Patent Application No. 2006-188232 filed on Sep. 27, 2016, the entire disclosure of which is incorporated herein by reference.

Interpolate the R signal with the average of the median surrounding value and the center, and generate a hue correction signal by interpolating the B signal with the median surrounding value, or generate the center of the surrounding image that correlates the R signal and the B signal with the color temperature or the amplification degree By generating a hue correction signal in which an R signal and a B signal are interpolated by a weighted average of a surrounding median value, such as generating a hue correction signal interpolated by a weighted average of values, color band maintenance and The present invention can be applied to an application in which improvement of color tone correction and maintenance of execution S / N are compatible. It is effective for studio photography, theater photography, concert photography, weather camera, medical use, inspection use, etc.
Also, by weighting and averaging the main line video signal with the median value and the central pixel in correlation with the color temperature or the amplification degree, priority is given to improvement of color tone correction and maintenance of the execution S / N over maintenance of the color band of the main line signal. Can be applied to In particular, under low illuminance shooting conditions, G also has high sensitivity, and the G video signal is effective in applications with much noise. It is effective for surveillance use, news coverage use, academic use, etc.

  1, 2, 3: subtractor, 4: hue area determination circuit, 5: saturation component amount, primary color component amount, and complementary color component amount determination circuit, 6: constant selection circuit, 7, 8: multiplier 9, 10: complement number Multiplier (-1 multiplier), 11: data selection and addition circuits 12, 13, 14: adder, 15: intermediate color hue setting circuit, 17: α / β, α / β calculation circuit, 18, 24, 25: constant Selection circuit, 16, 19, 20, 21, 22, 23, 26: multiplier, 21: data selection addition / subtraction circuit, 30: television camera, 31: lens, 32: prism (color separation optical system), 33R, 33G , 33B, 33G1, 33G2: CCD (charge coupled device) + AFE (analog front end processor) or CMOS image sensor, 34: parallel-serial converter, 35: video signal processor with hue detection correction function, 37: parallel- Shi Real conversion section, 39: CPU, 40: Viewfinder, 41: Gate section, 42: Excessive signal deletion section, 43: Peak detection section, 44: Serial-parallel conversion section with matrices, 45: Parallel-serial conversion section with matrices , 46: gamma correction unit, 47: imaging device with on-chip color filter.

Claims (7)

  In an imaging apparatus having a solid-state imaging device, the imaging apparatus includes means for halving the band of the R image signal and the band of the B image signal by half with respect to the band of the G image signal. And the center pixel image pickup signal are interpolated by a weighted average (including the median value or the average of the center value and the center pixel). An imaging apparatus comprising: a color tone correction unit configured to generate a color tone correction signal from a signal interpolated by a weighted average (including the median value or the average of the median value and the central pixel) of the imaging signal. In an imaging device having a solid-state imaging device,
An image sensor with color filters of Bayer array of R, G1, G2, and B and means for processing signals thereof, or a four-plate image sensor of R, G1, G2, and B, a color separation optical system, and means for processing signals thereof are provided. Then, at least in the bright portion, the R image signal is interpolated by a weighted average of the median value of the peripheral R pixel image signal and the center pixel image signal, or the R image signal is calculated by dividing the median value of the peripheral R pixel image signal and the center pixel image signal. A signal obtained by interpolating on average, and interpolating at least the bright portion of the B image signal by the weighted average of the median value of the peripheral B pixel image signal and the central pixel image signal or interpolating the B image signal by the median value of the peripheral B pixel image signal An image pickup apparatus comprising: a color tone correction unit that generates a color tone correction signal from the image data. The imaging device according to claim 2,
Means for transmitting (so-called DG transmission) for each of the four systems of R, G1, G2, and B, or R- (G1 + G2), G1, G2, B- (G1 + G2) or R- (Y1 + Y2), Y1, Y2, B -(Y1 + Y2) or RG1, G1, G2, BG2 or RY1, Y1, Y2, BY2 or RG2, G1, G2, BG1 or RY2, Y1, Y2, B -An imaging apparatus comprising means for transmitting two main signals, such as Y1 and the like, mainly of luminance and color. The imaging device according to any one of claims 1 to 3,
Means for processing the G video signal and means for processing the video signal of the RB pixel at an interval twice the interval of the G pixel, or means for transmitting the G video signal and the video signal of the RB pixel at an interval twice the interval of the G pixel Transmitting at least one of:
A means for detecting (calculating) a color temperature, and a weighted average of at least a bright portion of the R image signal which is positively correlated with the detected (calculated) color temperature of the median value of the peripheral R pixel image signal and the center pixel image signal. At least in the bright portion, color correction from a signal obtained by interpolating the B image signal with a weighted average negatively correlated with the detected (calculated) color temperature of the median value of the peripheral B pixel image signal and the center pixel image signal. Color tone correction means for generating a signal;
Means for varying the amplification degree of the RGB video signal, and at least the bright portion correlates the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (the center is smaller when the amplification degree is small). When the image signal of the R pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated. Interpolated by a weighted average correlated with the amplification degree of the RGB video signal with the center pixel imaging signal (for a small amplification degree, the center R pixel imaging signal is mainly, and for a large amplification degree, the central value of surrounding R pixel imaging signals is mainly). And a color tone correcting means for generating a color tone correction signal from the obtained signal. The imaging device according to claim 1, wherein
R, G1, G2, B imagers with color filters in a Bayer array and means for processing their signals, or R, G1, G2, B four-plate imagers, color separation optical system and means for processing their signals, Or a means for processing a G video signal and a means for processing a video signal of an RB pixel having an interval twice as long as the interval between G pixels, or a means for transmitting a G video signal and an image of an RB pixel having an interval twice as long as the interval between G pixels Means for transmitting signals, means for halving the band between the R video signal and the B video signal with respect to the G video signal, and the like. The image processing apparatus further includes a color tone correction unit configured to generate a color tone correction signal from a signal obtained by interpolating the average of the B pixel image signal with the center pixel image signal and interpolating the B image signal with the median value of every other peripheral B pixel image signal in G pixels. Imaging device.   In an image pickup apparatus having a solid-state image pickup device, there are provided three RGB plates and a means for signal processing of RGB signals from a color separation optical system. Interpolation by weighted average of the median value and the center pixel image signal or interpolation of the R image signal by the average of the median value and the center pixel image signal of every other surrounding R pixel image signal, and at least the bright part is also the B image signal A color tone correction signal is generated from a signal obtained by interpolating the B image signal with the median value of the center pixel of every other surrounding B pixel image pickup signal or the center value of the center pixel of every other surrounding B pixel image pickup signal. R- (G1 + G2), G1, G2, B- (G1 + G2) or R- (Y1 + Y2), Y1, Y2, B- (Y1 + Y2) or R-G1, G1, G2, B- G2 or R-Y1, Y1, Means for transmitting two signals, such as 2, 2, BY2 or R-G2, G1, G2, B-G1 or R-Y2, Y1, Y2, BY1, etc., as a signal mainly having luminance and a signal mainly having color. An imaging device comprising: In an imaging device having a solid-state imaging device,
Means for halving the band of the R video signal and the band of the B video signal with respect to the band of the G video signal,
The means for detecting (calculating) the color temperature, and the bright portion calculates the R image signal by a weighted average that is positively correlated with the detected (calculated) color temperature of the median value of the peripheral R pixel image signal and the center pixel image signal. The interpolation is performed, and the bright portion is obtained by weighting the B image signal with a weighted average that is negatively correlated with the detected (calculated) color temperature of the median value of the surrounding B pixel image signal and the center pixel image signal (the median value or the median value). A noise reduction unit that uses a signal interpolated by using the average of the median value and the central pixel) as a main line video signal;
The means for varying the amplification degree of the RGB video signal and the bright portion correlate the R imaging signal with the amplification degree of the R video signal between the median value of the surrounding R pixel imaging signal and the center pixel imaging signal (for small amplification degree, the central R When the image signal of the pixel is main and the amplification degree is large, the median value of the image signals of the surrounding R pixels is mainly interpolated), and the bright portion is obtained by interpolating the B image signal with the median value of the peripheral B pixel image signal and the central pixel. Interpolation by weighted average correlated with the amplification degree of the RGB video signal with the imaging signal (when the amplification degree is small, the imaging signal of the center R pixel is mainly, and when the amplification degree is large, the median value of the imaging signals of surrounding R pixels is mainly) An image pickup apparatus comprising: a noise reduction unit that converts the converted signal into a main line video signal.

Images