JPH02230885A - Color signal processing unit - Google Patents

Abstract

PURPOSE:To adjust the brightness and chromaticity of 3 color signals independently by adjusting the transmission quantity of a luminance signal Y and color difference signals R-Y, B-Y, applying signal conversion and obtaining the 3 color signals adjusted into desired brightness and chromaticity. CONSTITUTION:The unit is provided with a 1st signal conversion circuit 2 obtaining a luminance signal Y and color difference signals R-Y, BY based on R, G, B color signals and with an adjustment means 3 adjusting the transmission quantity of the luminance signal Y and color difference signals R-Y, B-Y. Moreover, the unit is provided with a 2nd signal conversion circuit 4 obtaining color signals R', G', B' whose brightness and chromaticity are adjusted based on the luminance signal Y, to be adjusted and the color difference signals R-Y', B-Y' to be adjusted. The brightness of the color signals R, G, B is adjusted by adjusting the transmission quantity of the luminance signal Y, and the chromaticity of a color signal G obtained by eliminating the color signals R, B from the luminance signal as well as th color signals R, B is desirably adjusted by adjusting the transmission quantity of the color difference signals R-Y and B-Y. Thus, the brightness and the chromaticity are easily adjusted.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a color signal processing circuit, and in particular to a color signal processing circuit that controls brightness and saturation in various video equipment such as TV receivers, VTRs, electronic cameras, and video printers. It is suitable for use when adjusting.

[Conventional technology] The video equipment generally has red (R), green (G), and blue (B) colors.
Color images are projected or printed on recording materials such as recording paper based on the color signals.

Then, by adjusting the signal level of each of the R, G, and B color signals, white balance and overall color adjustment can be performed.

However, when the color adjustment is performed, for example, when the level of red (R) is adjusted, the entire color image becomes reddish, and the brightness, saturation (color density, color It is not possible to adjust the vividness or color saturation.

Therefore, in the past, methods using matrix circuits and methods using digital processing circuits were considered in order to adjust the brightness and saturation of individual colors, but these color signal processing methods have the following problems. there were.

[Problems to be Solved by the Invention] That is, the method using a matrix circuit has problems such as it is difficult to adjust the coefficients, and the digital processing circuit has a complicated circuit configuration, which contributes to high costs. There is.

In order to solve the above problem, it is conceivable to provide an adjustment means for adjusting the overall level brightness and chroma for each of the R, G, and B color signals.

However, according to this adjustment method, it is necessary to provide as many as nine adjustment means such as volume, which causes problems such as not only the adjustment means becoming complicated but also the adjustment work becoming troublesome.

The present invention has been made in view of the above-mentioned circumstances, and its object is to provide a color signal processing circuit that can easily adjust the brightness and saturation of each color of a color image.

[Means for Solving the Problems] The object of the present invention is to calculate the transmission amount of the luminance signal Y obtained based on the R, G, and B color signals and the R-Y and B-Y color difference signals. At the same time, the desired brightness and saturation are adjusted based on the brightness signal Y and the color difference signals R-Y and B-Y, in other words, the brightness signal to be adjusted and the color difference signal to be adjusted in the present invention, whose transmission amount has been adjusted. This is achieved by configuring the system to obtain R, G, and B color signals.

[Operation] In the present invention configured as described above, the luminance signal Y
By adjusting the amount of transmission, the brightness of the color signals R, G, and B can be adjusted.

Furthermore, by adjusting the amount of transmission of the color difference signals R-Y and B-Y, not only the color signals R and B but also the color signal G obtained by dividing the color signal RSB from the luminance signal can be adjusted to the desired saturation. Can be adjusted.

The adjustment means includes a transmission path for the luminance signal Y and a color difference signal R-Y.
.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1 is a circuit diagram showing the basic concept of the present invention, FIG. 2 is a circuit diagram of a video printer showing an example of application of the present invention, and FIG. 3 is a perspective view of essential parts of a recording apparatus.

First, the basic concept of a color signal processing device to which the present invention is applied will be explained with reference to FIG.

A color signal processing circuit 1 includes a first signal conversion circuit 2 that obtains a luminance signal Y1 and a color difference signal R-Y, B-Y based on RSG and B color signals, and transmits a luminance signal Y1 and a color difference signal R-YSB-Y. Adjustment means 3 for adjusting the amount, and color signals R', G', B' whose luminance and saturation are adjusted based on the luminance signal Y' to be adjusted and the color difference signal R-Y', B-Y' to be adjusted. and a second signal conversion circuit 4 that obtains the following signal.

To explain the circuit operation below, the color signals RSG and B transmitted to the manual terminal are input to the input level adjustment volume VRI.
, VR2 and VR3, and the adder 11
, are supplied to subtractors 12 and 13.

The adding circuit 11 adds the color signals R and GSB to obtain a luminance signal Y. The ratio of addition is adjusted by the volumes VR1 to VR3, but according to the NTSC system, the luminance signal Y is Y=0.30ER+0.59EG
+O. It is obtained by adding the ratio of IIEB. Note that if the ratios of the color signals R, G, and B are determined in advance, the volumes VRI to VR3 may be deleted.

The subtraction circuit 12 subtracts the luminance signal Y from the color signal R to obtain a color difference signal RY, and the subtraction circuit 13 subtracts the luminance signal Y from the color signal R.
The color difference signal B-Y is obtained by subtracting the luminance signal Y from the signal Y.

Volumes VRII, VR12, and VR13 are provided on the transmission paths of the luminance signal Y and color difference signals RY, BY as adjusting means for adjusting the amount of transmission (level adjustment).

These volumes VRII to VR13 are provided to obtain color signals R', G', and B' whose brightness and saturation have been adjusted.

First, the adjustment of the brightness signal Y will be explained. By adjusting the volume VR12, the adjusted brightness signal Y' adjusted to a desired level can be obtained.

On the other hand, the volumes VRII and VR1 have an interlocking structure.
By adjusting 3, adjusted color difference signals R-Y' and B-Y' adjusted to desired levels can be obtained.

Incidentally, the addition circuits 21 and 22 and the subtraction circuit 23 are provided to obtain a color signal based on a luminance signal and a color difference signal, contrary to the addition circuit 11 and subtraction circuits 12 and 13.

That is, the adding circuit 21 adds the adjusted luminance signal Y' adjusted to the desired level to the adjusted color difference signal RY' adjusted to the desired level.

Then, from the addition circuit 21, a color signal R' adjusted to desired luminance and saturation is obtained.

The adding circuit 22 adds the adjusted luminance signal Y' adjusted to the desired level to the adjusted color difference signal B-Y' adjusted to the desired level.

Then, from the addition circuit 22, a color signal B' adjusted to desired brightness and saturation is obtained.

The subtraction circuit 23 extracts color signals B', B', and B' from the luminance signal Y' to be adjusted.
The color signal G' is obtained by subtracting R', so to speak, the first
The adder circuit 11 in the signal conversion circuit 2 performs the opposite operation.

The color signals R', G'B' obtained in this way are adjusted to desired brightness and saturation by the volumes VRII to VR13, which are adjusting means.

Moreover, the volumes VRII and VR13 are interlocked, so in reality, by adjusting the two volumes,
The brightness and saturation of each color signal will be adjusted.

The color signal processing circuit 1 described above can be widely applied to video equipment using color signals of three colors, and an example of its application to a video printer will be described below.

A video printer prints a color image based on a video signal photographed by an electronic still camera or the like or a video signal recorded.

In the video printer to which the present invention is applied, the color signal processing circuit 1 described with reference to FIG. be done.

Since the input circuit 31 is provided with the adjustment means as described above, the color signals R', G', and B' whose brightness and saturation are individually adjusted are obtained and supplied to the switch circuit 32. Ru.

On the other hand, the decoder 31 obtains normal color signals R and GSB separated into three colors from the luminance signal Y and color signal C supplied via the S terminal.

In this way, by providing two types of manual circuits, the video printer can be used for multiple purposes.

The switch circuit 32 selects the color signal obtained from the human circuit 30 and the color signal obtained from the decoder 31, and when switched as shown by the solid line, the color signal R'
, G', and B' are supplied to the encoder 33. Note that when the switch circuit 32 is switched as shown by the dotted line, the color signals R and GSB obtained from the decoder 31 are supplied to the encoder 33. A video signal with contrast, tint, brightness and color adjustment is obtained from the encoder 33 so that it can be viewed by the monitor TV.

The image printing operation for the color signals R', G', and B' will be explained below.The switch S1 is switched and the color signals R', G', and B' are sequentially supplied to the A/D converter 34. .

The print controller 35 performs interpolation correction processing on the digitized color signal, supplies this color signal, that is, image information to the line memory 36, and sequentially writes it into predetermined addresses.

When printing an image, the user operates the operation unit 37 to give a print instruction to the system controller 38.

The print controller 35 is the system controller 3
8, the image information written in the line memory 36 is read out, gamma correction, transfer characteristics, etc. are corrected, and then transferred to the thermal head 39.

While the above operations are performed, the system controller 38
A control signal is supplied from the servo circuit 40 to the servo circuit 40. and,
A servo circuit 40 controls a motor for running ink paper 51 and recording paper 52, which will be described later, and a drive mechanism 53.
control is performed.

Note that the clock signal generation circuit 41 includes a print controller 35, a line memory 36, and a system controller 3.
This is to supply a clock signal to the 8 etc. Further, the operation unit 37 is provided with a switch for selecting an operation mode of the video printer, a pilot for displaying the operation mode, and the like.

Next, the image recording section will be explained with reference to FIG.

The ink paper 51 coated with sublimable dye is configured to run in eight directions indicated by arrows by a pair of rollers 54a and 54b. Ink paper 51 is yellow Y, magenta M
The recording paper 52 is a three-color sequential roll coated with sublimation dye M of cyan C, and is wound around a platen drum 55.
The image is transferred during three rotations. That is, when a current pulse corresponding to image information is supplied from the print controller 35 to the electrodes of the thermal head 39, it is converted into thermal energy by the heating element.

This thermal energy heats the ink layer of the ink paper 51, vaporizes the sublimable dye, transfers it to the receiving layer of the recording paper 52, and solidifies it.

The transfer operation, in other words, the image recording operation is performed using Y, M, C.
By synchronizing the transfer positions, image transfer without color shift is performed.

In the video printer described above, the color signal processing circuit 1 of the present invention is applied as the human power circuit 30, and the color signal is adjusted to the desired brightness and saturation and then converted into image information, so that excellent images can be obtained. Records can be made.

Although the color signal processing circuit 1 of the present invention and its application examples have been described above, the present invention is not limited to the above.

For example, for the color signal processing circuit 1, the volume VR
Although II and VR 13 are constructed in an interlocking manner, they may be configured so that each can be adjusted independently. Further, the application of the color signal processing circuit 1 is not limited to the video printer described above, but can be widely used for color adjustment of TV receivers, VTR cameras, electronic still cameras, etc.

[Effects of the Invention] As described above, according to the color signal processing device of the present invention, signal conversion is performed after adjusting the amount of transmission of the luminance signal Y and the color difference signals R-Y, B-Y, and the desired signal is converted. Since it is configured to obtain color signals of three colors adjusted to the brightness and saturation of
The brightness and saturation of the three color signals can be adjusted independently.

Therefore, even if the brightness and saturation of the 10 color signals are adjusted, there is no problem such as the color of the entire color image changing.

Further, since the above adjustment can be performed simply by adjusting the transmission l of the three types of color signals, the circuit configuration becomes simple, and together with the reduction in the number of parts, it is possible to achieve a significant cost reduction.

Furthermore, adjustment work becomes easier, and the usability of the video equipment to which the present invention is applied can be improved.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing the basic concept of a color signal processing device to which the present invention is applied, FIG. 2 is a circuit diagram of a video printer, and FIG. 3 is a perspective view of main parts of a recording device. Reference numeral 1 in the figure: Two-color signal processing circuit 2: First signal conversion circuit 3: Adjustment means 4: Second signal conversion circuit l1, 21, 22: Addition circuit 12, 13, 23: Subtraction circuit 30: Human power circuit 51: Ink paper VR11 to VR13: Volume R, G, B: Color signal Y: Luminance signal RY, B-Y: Color difference signal. Figure Figure

Claims (1)

[Claims] Regarding a first signal conversion circuit that obtains a luminance signal and first and second color difference signals based on three color signals, and the luminance signal and the first and second color difference signals. an adjusting means for adjusting the transmission amount; and three colors adjusted to desired luminance and saturation based on the adjusted luminance signal, the first adjusted color difference signal, and the second adjusted color difference signal, which are adjusted to the desired transmission amount. and a second signal conversion circuit for obtaining a color signal.