JPH0654988B2 - Hue adjuster - Google Patents

Description

TECHNICAL FIELD The present invention relates to a hue adjusting device suitable for video equipment such as a video printer of R (red), G (green), and B (blue) input systems.

(Prior Art) Conventionally, in a printing apparatus which inputs a color video signal and reproduces an image on paper or the like, an R. G. A direct color signal that has not been converted into a standard television signal like the B input is often used as an input signal.

In such a so-called direct input color video device, when the hue is adjusted, for example, R.I. G. Only the method of adjusting the hue by adjusting the level of each input signal of B has been considered.

However, if such a method of adjusting each color signal is individually used, the color saturation also changes each time, and it is very difficult to obtain a desired hue smoothly.

(Object) The present invention has an object to provide a hue adjusting device capable of solving the drawbacks of the prior art.

In particular, it is an object of the present invention to provide a hue adjusting device in which hue adjustment is easy.

(Example) The present invention will be described in detail based on the following examples.

FIG. 1 is a schematic diagram of the first embodiment of the present invention.

Reference numeral 1 denotes a matrix circuit, which has three functions using the RGB input signals as parameters (variables), for example, To form.

Here, (RY) is, for example, a first function, and (BY) is a second function.

Reference numeral 11 denotes an operation member for setting a hue, which outputs a predetermined value φ.

2 and 3 are the trigonometric functions cosφ and sinφ with this value φ variable respectively.
Is a trigonometric function circuit that outputs respectively.

Reference numerals 4 to 7 denote multiplication circuits. The multiplication circuits 4 and 5 multiply the (BY) signal by cosφ and sinφ, respectively. The multiplication circuits 6 and 7 multiply the (RY) signal by cosφ and sinφ, respectively. Circuit.

Reference numerals 8 and 9 denote mixer circuits. The circuit 8 adds the output of the circuit 4 and the output of the circuit 6, and the circuit 9 adds the inverted output of the circuit 5 and the output of the circuit 7.

Therefore, the output (BY) (φ) of the circuit 8 becomes (BY) (φ) = (BY) cosφ + (RY) sinφ ..., and the output (RY) (φ) of the circuit 9 is (RY) (φ) = − (BY) sinφ + (RY) cosφ …….

Therefore, tentatively, as shown in the second diagram, the saturation C represented by the coordinates of the (RY) axis and the (BY) axis, the color Z of the hue γ (Ccosγ,
About Csinγ) Can be expressed as Can be expressed as

That is, the color represented by Z (Ccosγ, Csinγ) on the (RY) axis and the (BY) axis is represented by the coordinate system in which the color is rotated counterclockwise by φ. Z '(Ccos (γ- φ), Csin (γ−φ)).

As a result, without changing the saturation (color saturation) at all,
The effect equivalent to shifting the hue by φ in the clockwise direction can be obtained.

In the present invention, after performing such conversion, in the matrix circuit 10, from the Y signal and the (BY) (φ), (RY) (φ) signals, R (φ), G (φ), B ( By forming each signal of φ), it is possible to finally obtain a color signal in which the hue of each color signal is shifted by φ.

Next, FIG. 3 is a diagram showing a configuration example of the trigonometric function circuit according to the present invention. The value φ output from the operating member 11 is converted into a digital signal by the A / D converter 16. This digital signal is ROM (Read Only Memory) 12, 1
It is input as the address signal of No. 3.

Data is stored in the ROMs 12 and 13 so that a function is generated by a table look-up at an address corresponding to the address signal.

That is, the cos function is stored in the ROM 12 and sin is stored in the ROM 13.
The function is remembered.

Therefore, from the ROMs 12 and 13, c corresponding to the operation member 11
Digital signals of osφ and sinφ are output and converted into analog quantities cosφ and sinφ by the D / A converters 14 and 15, respectively.

As described above, in the present invention, the hue is not adjusted by changing the level of each color signal (for example, RGB), but the color signals are once converted into two types of functions having variables, and then each function is predetermined. A multiplication circuit for multiplying a trigonometric function whose phase is the variable is provided, and the color signals are formed again after mixing the outputs of this multiplication circuit.
Hue adjustment can be easily performed by one operation member, and a desired hue can be obtained very easily. Further, since only the hue can be adjusted independently without changing the color saturation level when adjusting the hue, the operability is superior to the conventional one.

Further, in this embodiment, (RY) and (BY) are used as the first and second functions.
Since this is used, a general-purpose IC for processing television signals can also be used.

In the above embodiment, RGB input was considered, but
(Yellow), Ma (magenta), Cy (cyan), and K (black) input may be used. In addition, it is applicable to all color video equipment such as monitor TVs of the type that inputs multiple color signals independently. It goes without saying that it is possible.

Further, in the embodiment, (RY) and (BY) are considered as the first and second functions, but they may be combined with, for example, (GY).

Alternatively, one of the I signal and the Q signal in the standard television signal may be the first function and the other may be the second function.

(Effect) As described above, according to the present invention, it is possible to perform hue adjustment in a color video device that uses a direct input signal such as RGB without affecting the color saturation.

Further, the hue can be easily adjusted by operating only one operating member. In addition, there are many effects such as simplification of the circuit configuration.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a hue adjusting device of the present invention, and FIG.
FIG. 3 is a diagram for explaining the effect of the first illustrated configuration, and FIG. 3 is a diagram for explaining a configuration example of a trigonometric function circuit. 1, 10 ... Matrix circuit, 11 ... Operating member, 2, 3 ... Trigonometric function circuit, 4-7 ... Multiplication circuit, 8, 9 ... Mixer circuit.

Claims (1)

[Claims] 1. A hue setting signal generating means for generating a hue setting signal for setting a hue, and the hue setting signal generating means for the first baseband color difference signal and the second baseband color difference signal which are different from each other. The first baseband color difference signal and the second baseband, which are respectively multiplied by a first trigonometric function having a phase set by a hue setting signal generated by the The color difference signal is multiplied by a second trigonometric function different from the first trigonometric function whose variable is the phase set by the hue setting signal generated by the hue setting signal generating means, and then output. 2 multiplication means, a first baseband color difference signal multiplied by the first trigonometric function output from the first multiplication means, and the second trigonometric function output from the second multiplication means. Is multiplied And a second baseband color difference signal to form a hue-adjusted first baseband color difference signal, and output the addition means; and the first triangle output from the first multiplication means. From the second baseband color difference signal multiplied by the function, the second
Subtracting the first baseband color difference signal multiplied by the second trigonometric function outputted from the multiplying means to form a hue adjusted second baseband color difference signal, and outputting the subtraction means. A hue adjusting device having.