JPH11187419A - Unit and method for signal processing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute with a simple configuration a complicated nonlinear processing in real time by inversely converting third color image signals into fourth color images which are being a first color space sequentially based on a third conversion table. SOLUTION: A color space conversion section 12 of a color processing unit 10 converts a digital red signal S1R, a digital green signal S1G, and a digital blue signal S1B, which are given from externally, into a lightness signal V1, a hue signal H1, and chromaticity signal C1 in a uniform visual perception space. The converted signals are color-processed nonlinearly by a color processing section 12, a lightness signal V2, a hue signal H2, and chromaticity signal C2 obtained by the section 12 are given to a color space inverse conversion section 13, where the signals are converted inversely into a digital red signal S3R, a digital green signal S3G, and a digital blue signal S3B of the original signal form and outputted. Then the from conversion processing, the color processing and the inverse conversion processing of the color space are conducted by means of a loockup table system employing plural nonvolatile memories.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Table of Contents] The present invention will be described in the following order.

BACKGROUND OF THE INVENTION Problems to be Solved by the Invention (FIG. 5) Means for Solving the Problems (FIGS. 1 to 4) Embodiments of the Invention (1) Colors According to the Present Embodiment Configuration of processing apparatus (FIGS. 1 to 4) (2) Conversion table write processing and change processing (FIGS. 1 to 4)
(FIG. 4) (3) Operation and effect of this embodiment (FIGS. 1 to 4) (4) Other embodiments (FIGS. 1 to 4) Effects of the invention

[0003]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing apparatus and a signal processing method, and is suitably applied to, for example, a color processing apparatus for performing color processing on a digitized color image signal.

[0004]

2. Description of the Related Art Hitherto, a color processing apparatus has been configured to perform predetermined signal processing on a color image signal based on an operation of an operator to change a color condition of a color image based on the color image signal. When repairing the color condition of an image with poor imaging conditions such as weather or lighting, or an image whose color has deteriorated due to transmission via an analog transmission line before broadcasting, or combining video and film images This is used for adjusting the delicate colors of both when performing the editing.

[0005]

Among the conventional color processing apparatuses which are capable of performing color processing on a digitized color image signal, those which can perform real-time processing include: There have been many types in which each of the red (R), green (G) and blue (B) primary color signals forming a color image signal is subjected to linear processing.

Another type of color processing apparatus capable of performing color processing in real time is an apparatus capable of adjusting the hue by rotating the phase of a color carrier signal of a composite signal. Also,
This type is used in a form incorporated in a monitor or a video tape recorder.

However, in the former type of color processing apparatuses, since the linear processing is performed on each primary color signal, it is difficult to partially adjust hue and brightness (ie, non-linear processing). There was a problem. Also, in the latter type, since the entire hue is shifted when the phase of the color carrier signal is rotated, there is a problem that it is difficult to partially adjust the hue and brightness as in the former type.

On the other hand, as a color processing apparatus on the premise of advanced color processing including non-linear processing, three primary color signals are converted into component signals of a lightness signal, a hue signal and a chromaticity signal (by converting a color space). ) Some are handled, but this is non-real-time processing by software processing, and the processing time is generally indefinite and long, so its application is centered on still image processing. Things.

As described above, conventionally, there is no color processing apparatus capable of performing complicated non-linear color processing in real time. For this reason, for example, color processing such as hue and brightness of a part of a moving image can be performed in a desired state in real time. There was a difficult problem.

In order to perform the color processing in real time, first, it is necessary to have a capability of processing one pixel at intervals of, for example, 13.5 [MHz], and the delay time is fixed and the delay time is fixed. It is also desirable that the distance be within a few frame intervals from the viewpoint of usability.

For this purpose, a CPU (Central Process i) is used to realize complicated processing by conventional software.
ng Unit), etc., or by using CPUs in parallel. However, the former method has its limitations, and the latter method requires high manufacturing costs for both software and hardware. There's a problem.

Although it is conceivable to replace the color processing with hardware processing by a digital signal processing circuit, there is a problem in achieving sufficiently high functions, and the digital signal processing circuit is not suitable for nonlinear processing. There is also.

Secondly, when a non-linear process is performed as a color processing process on a color image signal, for example, three colors are used.
It is considered necessary to have a function that enables processing in a color space suitable for nonlinear processing, instead of processing in a color space that has a theoretical problem in performing nonlinear processing, such as expressing as a combination of primary colors. .

In this case, in order to perform drastic nonlinear processing on the color image signal, brightness (brightness), color (hue) and color intensity (chromaticity) perceived by a human are completely separated. Moreover, the numerical difference is equal to the difference in human sensation (for example, a human perceives a difference of 1 bit at any level as a difference in color). For example, a so-called uniform visual perception such as a modified Munsell color space. It is desirable to be able to perform processing in space from the viewpoint of usability.

However, the process of converting the color space of the color image signal from the color space of the three primary color signals to, for example, the corrected Munsell color space is a non-linear conversion process. Therefore, such a non-linear process is performed only by hardware processing. Attempting to do so has a problem in that the construction of the conversion circuit is difficult.

In addition, there are proposals for the uniform visual perception space other than the modified Munsell color space, and it is conceivable that a color space suitable for this type of processing will be proposed in the future. A device that can be changed is desired.

Third, in order to enhance the functions of the color processing apparatus, it is necessary to devise a method for easily changing the contents of the processing.
Actually, the color processing by software is relatively easy, but it is not easy to realize mainly by hardware. Fourth, it is also important from the viewpoint of practical use of the apparatus to keep the hardware scale of the entire apparatus as small as possible and to reduce its realization cost.

Under these conditions, a method of constructing a color processing apparatus as shown in FIG. 5 can be considered. In practice, in the color processing apparatus 1, for example, an 8-bit digital red signal S1R, digital green signal S1G, and digital blue signal S1B of 8 bits are supplied from the first to the first, respectively.
By combining in the third input side switch circuits 2A to 2C, a 24-bit combined signal S2 is generated, and these are respectively corresponding to the first to third nonvolatile memories 3A to 3A.
Input to C.

At this time, the first to third nonvolatile memories 3A
The ～3C, digital red signal, such as image color condition is obtained a combined signal S2 to a desired operator to enter each of 2 ²⁴ converts data to be converted into digital green signal and digital blue signals respectively synthesized The value corresponding to the signal S2 is stored as an address.

Thus, the first to third nonvolatile memories 3A
3C read the corresponding converted data using the value of the supplied composite signal S2 as an address, and output the corresponding first to third outputs as the digital red signal S3R, the digital green signal S3G, or the digital blue signal S3B, respectively. Output to the outside via the side switch circuits 4A to 4C.

Here, in the case of the color processing apparatus 1, the above-described conversion data is calculated by the personal computer 5, and under the control of the CPU 7, the correspondence of the first to third nonvolatile memories 3A to 3C is calculated. Is stored at the address location where

In practice, the personal computer 5 converts the component signals of the digital red signal S1R, the digital green signal S1G, and the digital blue signal S1B into digital images capable of obtaining brightness, hue, and chromaticity images corresponding to the operation input of the operator. Red signal S3R, digital green signal S3G or digital blue signal S3B
The value of the conversion data D1 to be converted into is calculated sequentially for each value of the composite signal S2.

The personal computer 5 converts the converted data D1 thus obtained from the one having the smaller value of the composite signal S2 and the one corresponding to the digital red signal S1R, the digital green signal S1G and the digital blue signal S1B in order. This is given to the CPU 7 via the interface circuit 6 of the color processing device 1.

The CPU 7 supplies each of the conversion data D1
To the corresponding first to third non-volatile memories 3A to 3C via the data bus 8 and the corresponding first to third output side switch circuits 4A to 4C sequentially, and together with this, the digital red signal S1R, digital green signal S
Each set of conversion data D1 corresponding to 1G and the digital blue signal S1B is taken as one set, and one set of conversion data D
Each time 1 is supplied, an address corresponding to each conversion data D1 is generated while sequentially increasing the value by one, and this is used as an address signal S4 as an address bus 9 and the corresponding first to third input-side switch circuits 2A. To 2C sequentially to the corresponding first to third nonvolatile memories 3A to 3C.

As described above, in the color processing apparatus 1, the conversion data D1 is stored in the first to third nonvolatile memories 3A to 3C at the corresponding address positions based on the address signal S4.

When a change in the color processing is subsequently input by the operator, the personal computer 5 calculates conversion data D1 corresponding to the change as described above.
The obtained converted data D1 is transmitted to the CPU 7 in the same manner as described above.
Under the control of the CPU 7 in the same manner as described above, and sequentially stores the converted data D1 at the corresponding address positions of the first to third nonvolatile memories 3A to 3C. In this way, the color processing device 1 changes each conversion data D1 to conversion data D1 having a value that can obtain an image of a color condition specified by the operator.

In such a color processing apparatus 1, the supplied digital red signal S1R, digital green signal S1G, and digital blue signal S1B are each converted into a digital red signal according to an image of a desired color condition by a look-up table system. Since the signal S3R, the digital green signal S3G, and the digital blue signal S3B are converted, the color processing can be performed in real time, and the conversion data D1 stored in the first to third nonvolatile memories 3A to 3C is adjusted. Thus, there is an advantage that only a part of the brightness, hue and / or chromaticity can be freely adjusted (non-linear processing).

However, in the color processing apparatus 1 having such a configuration,
The color processing is performed by reading the conversion data D1 stored at the corresponding address position from the first to third nonvolatile memories 3A to 3C using the value of the composite signal S2 as an address. No. 1 for each change
All the conversion data D1 (each of 2 ²⁴ ) stored in the third nonvolatile memories 3A to 3C must be changed, and the calculation of the conversion data D1 and the first to third conversion data D1 are performed.
However, there is a problem that a great amount of time is required for downloading to the nonvolatile memories 3A to 3C.

The present invention has been made in view of the above points, and it is an object of the present invention to propose a signal processing apparatus and a signal processing method capable of performing complicated nonlinear processing with a simple configuration in real time.

[0030]

According to the present invention, there is provided a signal processing apparatus, comprising: a first processing unit which supplies a predetermined first conversion table based on the first conversion table stored in a first storage unit; Color space conversion means for sequentially converting a first color image signal in one color space into a second color image signal in a predetermined second color space according to human visual characteristics;
On the basis of the second conversion table stored in the second storage means, the second color image signal is sequentially converted into a third color image signal in the second color space to which a predetermined nonlinear process has been performed. Conversion means for converting, and the third color image signal output from the conversion means based on the third conversion table stored in the third storage means, in the fourth color space of the first color space Color space inverse conversion means for sequentially inversely converting image signals is provided.

As a result, in this signal processing apparatus, various complicated nonlinear processes such as a color space conversion process and an inverse conversion process and a color processing process are stored in the first to third storage means. 3 can be performed in real time by a look-up table method using the conversion table. This signal processing device can be easily constructed.

Further, according to the present invention, in the signal processing method, the first color image signal represented in the predetermined first color space is determined based on a predetermined first conversion table in accordance with human visual characteristics. The second color image signal is subjected to predetermined non-linear processing based on a first step of sequentially converting the second color image signal into a second color image signal of a predetermined second color space and a predetermined second conversion table. A second step of sequentially converting the third color image signal into a third color image signal of the second color space, and a third color image signal of the first color space based on a predetermined third conversion table. And a third step for sequentially inverting the color image signals into the four color image signals.

As a result, in this signal processing method, various complicated nonlinear processes at the time of color processing, such as color space conversion processing and inverse conversion processing, and color processing processing, are performed using the first to third conversion tables. It can be performed in real time by the up-table method. Further, the configuration of a signal processing device that performs such signal processing can be simplified.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

(1) Configuration of the Color Processing Apparatus According to the Present Embodiment In FIG. 1, reference numeral 10 denotes a color processing apparatus according to the present embodiment as a whole, and a digital red signal S1R, a digital green signal S1G, and a digital signal supplied from outside. The component signal of the blue signal S1B is converted into a color space
In the modified Munsell color space into component signals of the lightness signal V1, the hue signal H1, and the chromaticity signal C1, and these lightness signal V1, the hue signal H1, and the chromaticity signal C1 are converted.
1 is subjected to nonlinear color processing in accordance with the operation input of the operator in the color processing unit 12, and then the obtained component signals of the lightness signal V2, the hue signal H2, and the chromaticity signal C2 are subjected to color space inverse conversion. In the section 13, the digital red signal S3R, the digital green signal S3G, and the digital blue signal S3B are inversely converted into component signals and output.

Actually, in the color processing apparatus 10, the color space conversion section 11 and the color processing section 12 are configured as shown in FIG. 2, and in the color processing mode, for example, each of eight bits provided from outside is provided. The digital red signal S1R, the digital green signal S1G and the digital blue signal S1B are converted into first to third input-side switch circuits 2 of the color space converter 11.
Each of the synthesized signals is synthesized at 0A to 20C, and the obtained 24-bit synthesized signal S10 is sent to the corresponding first to third nonvolatile memories 21A to 21C.

At this time, the first to third nonvolatile memories 21
Each of A to 21C contains 2 ²⁴ conversion data for converting the synthesized signal S10 into an 8-bit lightness signal, hue signal, or chromaticity signal in the uniform visual perception space in advance.
Is stored as an address.

Thus, the first nonvolatile memory 21A
Based on the composite signal S10 supplied from the first input-side switch circuit 20A, the converted data is read from the corresponding address position using the value of the composite signal S10 as an address, and this is used as a brightness signal V1 as a first output-side switch circuit. The signal is sent to the first timing adjustment delay circuit 23A of the color processing section 12 via the second processing section 22A.

Further, the second nonvolatile memory 21 B
The composite signal S supplied from the input side switch circuit 20B of FIG.
10, the converted data is read out from the corresponding address position using the value of the composite signal S10 as an address, and this is used as the hue signal H1 as the second output-side switch circuit 22.
B and the second input-side switch circuit 2 of the color processing unit 12
4B to the second non-volatile memory 25B of the color processing unit 12 in order.

Further, based on the composite signal S10C supplied from the third input-side switch circuit 20C, the third nonvolatile memory 21C reads the conversion data from the corresponding address position using the value of the composite signal S10C as an address, This is sent as a chromaticity signal C1 to the second timing adjustment delay circuit 23B of the color processing section 12 via the third output side switch circuit 22C.

At this time, in the second non-volatile memory 25B of the color processing section 12, for example, a color close to a pure color is converted into a pure color in order to increase the purity of the color, or all the red colors are converted into a blue color. Twenty- ^eight pieces of conversion data for converting a part or all of the hue of the image into a state according to the instruction of the operator are stored with the corresponding value of the hue signal H1 as an address.

Thus, the second nonvolatile memory 25B
Based on the supplied hue signal H1, the converted data at the corresponding address position is read out using the value of the hue signal H1 as an address, and this is converted as a hue signal H2 after color processing via the second output-side switch circuit 26B. First and third
To the output side switch circuits 24A and 24C and the first to third input side switch circuits 27A to 27C of the color space inverse conversion unit 13 shown in FIG.

On the other hand, the brightness signal V1 given to the first timing adjustment delay circuit 23A of the color processing section 12 is a predetermined time during which the hue signal H1 is converted into the hue signal H2 in the first timing adjustment delay circuit 23A. After being delayed by an amount, the signal is supplied to a first input side switch circuit 24A,
After being combined with the hue signal H2 in the first input side switch circuit 24A, the 16-bit lightness and hue signal VH
1 is given to the first nonvolatile memory 25A.

At this time, the first non-volatile memory 25A of the color processing unit 12 stores, for example, the dynamic range of the brightness of only the portion having no color, or the brightness of the pure color portion to make the screen vivid. When the value is increased, converted data for converting part or all of the brightness of the original image into a state in accordance with the instruction of the operator becomes 2 ^{8 for} each hue level.
The values corresponding to the brightness and hue signal VH1 are stored as addresses, one by one.

Thus, the first nonvolatile memory 25A
Using the values of the supplied lightness and hue signal VH1 as an address, the converted data at the corresponding address position is read out, and this is converted into a lightness signal V2 after color processing, via a first output-side switch circuit 26A, to a color space inverse converter. 13 (FIG. 3) to the first to third switch circuits 27A to 27C, respectively.

Similarly, the chromaticity signal C1 supplied to the second timing adjustment delay circuit 23B of the color processing section 12 is converted into the hue signal H1 by the first timing adjustment delay circuit 23B. After being delayed by a predetermined time to be converted into the subsequent hue signal H2, the signal is applied to the third input side switch circuit 24C, and is combined with the hue signal H2 in the third input side switch circuit 24C.
The chromaticity and hue signal CH1 of the bit is supplied to the third nonvolatile memory 25C.

At this time, in the third nonvolatile memory 25C of the color processing section 12, for example, if the chromaticity value of only the pure color portion is increased to make the screen vivid, part or conversion for converting all of the state in accordance with an instruction of the operator data is stored the corresponding values of the chromaticity and the hue signal CH1 by two ^eight per level of each color as an address.

Thus, the third nonvolatile memory 25C
Using the value of the supplied chromaticity and hue signal CH1 as an address, the conversion data at the corresponding address position is read out, and this is converted as a chromaticity signal C2 after color processing through the third output-side switch circuit 26C to reverse the color space. The signal is sent to the first to third input-side switch circuits 27A to 27C of the conversion unit 13, respectively.

Further, in this manner, the color space inverse converter 13
Brightness signal V2, hue signal H2 and chromaticity signal C2 supplied to the first to third input side switch circuits 27A to 27C.
Are the first to third input-side switch circuits 27A to 27A
7C, the synthesized signal S of 24 bits is synthesized.
11 corresponding to the first to third nonvolatile memories 28A
~ 28C.

At this time, each of the first to third non-volatile memories 28A to 28C has a combined signal S of 24 bits.
8-bit digital red signal of the 11A～S11C, digital green signal or ²⁴ converts the data synthesis signal S11A~S11C for converting the digital blue signal
Is stored as an address.

Thus, the first to third nonvolatile memories 28
A to 28C read the converted data stored at the corresponding address positions based on the combined signals supplied from the corresponding first to third input-side switch circuits 27A to 27C, and read the converted data from the digital red signal S3.
R, which is output to the outside as a digital green signal S3G or a digital blue signal S3B.

Thus, in the color processing apparatus 10,
The brightness, hue, and chromaticity of a part or all of the image based on the supplied digital red signal S1R, digital green signal S1G, and digital blue signal S1B are color-processed to a state designated in advance by an operator, and the digital red signal S3R is processed. It is output to the outside as a digital green signal S3G and a digital blue signal S3B.

The first to third nonvolatile memories 21A to 21C of the color space converter 11 (FIG. 2) and the first to third nonvolatile memories 28A to 28C of the color space inverse converter 13 (FIG. 3) Is shown in FIG.

As is clear from FIG. 4, the first to third nonvolatile memories 21A to 21C of the color space conversion unit 11
The first to third non-volatile memories 28A to 28C of the color space inverse conversion unit 13 are general-purpose 21-input and 8-output 16-megabit RAMs (Random Access Memory) 30A to 30A, respectively.
It is constructed using eight Hs.

Each of these 16 megabit RAMs 30A
-30H are input 24-bit synthesized signals S10 and S10.
The converted data for each class when 2 ²⁴ 8-bit converted data respectively corresponding to each value of 11 are divided into 8 classes according to, for example, upper 3 bits or lower 3 bits of the composite signals S10 and S11. (2 ²¹ pieces) are stored. Each of these 16 megabit RAMs 30A-30
H is provided with data corresponding to the lower 21 bits or upper 21 bits corresponding to the combined signals S10 and S11 to be input.

Thus, each of these 16 megabit RAM 30
A to 30H are input lower 21 bits or upper bits, respectively.
Using the values of the composite signals S10 and S11 for 21 bits as an address, the conversion data at the address position is read out, and this is converted from the most significant bit (MSB) to the LSB.
(Least Signicant Bit) 1st to 8th by 1 bit
To the data selector circuits 31A to 31H.

Therefore, for example, the first data selector circuit 3
1A is supplied with MSB data of each converted data output from each 16-megabit RAM 30A, and the second data selector circuit 31B is provided with the second most significant bit data of each converted data output from each 16-megabit RAM. Similarly, the third to eighth data selector circuits are supplied with the corresponding bit data of the respective converted data output from the respective 16 megabit RAMs.

At this time, each of the first to eighth data selector circuits 31A to 31H has these 16-megabit RAMs.
The synthesized signal S1 to be input together with the corresponding bit data of each converted data output from each of 30A to 30H.
0, data of upper 3 bits or lower 3 bits of S11 are given.

Thus, the first to eighth data selector circuits 31A to 31H supply the combined signals S10, S11
Based on the data of the upper 3 bits or lower 3 bits, the conversion data read from the corresponding 16-megabit RAMs 30A to 30H is read and output.

Thus, the nonvolatile memory 21A
To 21C and 28A to 28C are the combined signals S10 and S10 as the whole of the first to eighth data selector circuits 31A to 31H.
8 bits of converted data read from the 16 megabit RAMs 30A to 30H corresponding to the data values of the 11 upper 3 bits or the lower 3 bits are output.
Thus, as described above, the brightness signal V1 and the hue signal H
1. Output as chromaticity signal C1, digital red signal S3R, digital green signal S3G or digital blue signal S3B.

(2) Conversion Table Writing Processing and Change Processing Here, the first to third nonvolatile memories 21A to 21C of the color space conversion section 11 and the first to third nonvolatile memories of the color processing section 12 The process of writing the conversion tables into the first to third nonvolatile memories 28A to 28C of the color space inverse conversion unit 13 and the process of changing these conversion tables are performed by the following procedure.

That is, in the case of the color processing apparatus 10, the digital red signal S 1
R, digital green signals S1G and digital blue signal value signal V1 of 8 bits of equal visual perception space S1B, hue signal H1 and respectively converted to the 2 ⁸ conversion data D10A~D10C for the chromaticity signal C1 personal The conversion data D10A to D10C calculated by the computer 40 are sequentially provided to the CPU 42 via the interface circuit 41 of the color processing apparatus 10.

The CPU 42 supplies each conversion data D
The data bus 43 and the color space conversion unit 1
And the corresponding first to third non-volatile memories 21A to 21A through the corresponding one of the output-side switch circuits 22A to 22C.
1C, while generating a corresponding address together with the address, and using this as an address signal S20.
And the corresponding input-side switch circuit 2 of the color space conversion unit 11
0A to 20C are sequentially applied to the corresponding first to third nonvolatile memories 21A to 21C.

As a result, each of the converted data D10A to D10C
Correspond to the first to third nonvolatile memories 21A to 21C.
Are applied to the corresponding 16-bit RAMs 30A to 30H via the first to eighth data selectors 31A to 31H, and the address signal S20 is also supplied to the corresponding 16-bit RAM 30A to 30H.
When given to AMs 30A to 30M, each converted data D10A to D11C is converted to a corresponding 16 megabit RA in first to third nonvolatile memories 21A to 21C, respectively.
It is stored in the corresponding address position in M30A-30M.

In the initial stage, the personal computer 40 similarly converts the lightness signal V2, the hue signal H2 and the chromaticity signal C2 into an 8-bit digital red signal R3R and a digital green signal R3G in the color space inverse converter 13.
And calculating the respective 2 ⁸ conversion data D11A~D11C for converting each of the digital blue signal R3B,
These are given to the CPU 42 via the interface circuit 41 of the color processing device 10.

The CPU 42 converts the supplied conversion data D
The first to third nonvolatile memories 28A to 28A to 11A to D11C are sequentially passed through the data bus 43 and the corresponding output-side switch circuits 29A to 29C of the color space inverse converter 13.
28C, while generating a corresponding address together with the address, and using this as an address signal S20.
4 and the corresponding first to third non-volatile memories 28A to 28C via the corresponding input side switch circuits 27A to 27C of the color space inverse conversion unit 13 sequentially.

As a result, each conversion data D11A to D11C
Correspond to the first to third nonvolatile memories 28A to 28C.
Are applied to the corresponding 16-bit RAMs 30A to 30H via the first to eighth data selectors 31A to 31H, and the address signal S20 is also supplied to the corresponding 16-bit RAM 30A to 30H.
The conversion data D11A to 11D are supplied to the AMs 30A to 30M so that the converted data D11A to 11D respectively correspond to the corresponding 16-megabit RAMs 3 of the first to third nonvolatile memories 28A to 28C.
It is stored in the corresponding address position in 0A to 30M.

[0068] Further the personal-computer 40, initial time, 2 and ⁸ conversion data D12B to convert the hue signals H1 to the hue signal H2 of 8 bits corresponding to the operation input by the operator in the color processing section 12, the brightness and the 2 ⁸ × 2 ⁸ pieces of conversion data D12A to convert the hue signals VH1 to lightness signal V2 operations 8 bits corresponding to the input operator, corresponding to chromaticity and color signals CH1 to an operation input of the operator 8 bits of for converting the chromaticity signal C2 2 ⁸ × 2 ⁸ pieces of conversion data D12C and was calculated, giving the CPU42 through the INTERFACE circuit 41 of the sequential color processing apparatus 10.

At this time, the CPU 42 converts the supplied conversion data D12A to D12C into the data bus 43 and the corresponding output-side switch circuits 26A to 26 of the color processing unit 12.
C, the corresponding first to first color processing units 12
While being supplied to the third nonvolatile memories 25A to 25C, a corresponding address is generated together therewith, and this is generated as an address signal S20 by the address bus 44 and the color processing unit 12.
Corresponding to the first to third nonvolatile memories 225A to 225A through the corresponding input-side switch circuits 24A to 24C.
Give 5C. In this way, the CPU 42 determines whether each of the first to third color processing units 12 is based on the address signal S20.
The conversion data D12A to D12C respectively corresponding to the corresponding address positions of the nonvolatile memories 25A to 25C are stored.

On the other hand, when the personal computer 40 subsequently converts the color space in which the color processing is performed by, for example, an operation of the operator, the personal computer 40 similarly converts the converted data D10A to D10A to D10A to D10A to D10A corresponding to the new color space. D10C,
D11A to D11C are the first of the color space conversion unit 11, respectively.
To the third nonvolatile memories 21A to 21C and the first to third nonvolatile memories 28A to 28C of the color space inverse conversion unit 13.
Is stored in the address position corresponding to.

As described above, in the color processing system including the color processing apparatus 10 and the personal computer 40, the color space conversion processing in the color space conversion unit 11 and the color space inverse conversion processing in the color space inverse conversion unit 13 Can be easily changed to a conversion process or an inverse conversion process corresponding to a new color space according to the operation of the operator.

Similarly, upon completion of the above-described initialization, the personal computer 40 receives an operation input to change the brightness, hue, and / or chromaticity to a state desired by the operator, for example, by an operation of the operator. ,
Converting the color signals H1 2 and ⁸ conversion data D12B to convert the hue signal H2 of 8 bits in response thereto, the brightness and hue signals VH1 to lightness signal V2 of 8 bits corresponding to the operation input by the operator 2 ⁸ × 2 ⁸ pieces of conversion data D12A and, 2 ⁸ × 2 ⁸ pieces of conversion data for converting the chromaticity and hue signal CH1 to the chromaticity signal C2 of 8 bits corresponding to the operation input by the operator D12C for Are calculated, and these are sequentially supplied to the CPU 42 via the interface circuit 41 of the color processing apparatus 10.

As a result, each of these converted data D12A-D
12C is stored in the corresponding first to third non-volatile memories 25A to 25C of the color processing unit 12 under the control of the CPU 42 as described above.

As described above, in the color processing system including the color processing device 10 and the personal computer 40, the contents of the color processing in the color processing section 12 can be easily changed to the contents of a new color processing in accordance with the operation of the operator. It can be changed to.

(3) Operation and Effect of the Present Embodiment In the above configuration, the color processing apparatus 10 converts the digital red signal S1R, digital green signal S1G, and digital blue signal S1B supplied from the outside into the color space conversion unit 11 After converting into a lightness signal V1, a hue signal H1, and a chromaticity signal C1 in the uniform visual perception space, and performing a non-linear color processing in the color processing unit 12, the obtained lightness signal V2, hue signal H2, and color The degree signal C2 is inversely converted by the color space inverse converter 13 into a digital red signal S3R, a digital green signal S3G, and a digital blue signal S3B in the original signal form and output.

In this case, in the color processing apparatus 10, the color space conversion processing in the color space conversion unit 11 is performed by the synthesized signal S10.
The corresponding conversion data D10A to D10C stored in the first to third non-volatile memories 21A to 21C of the color space conversion section 11 of the color space conversion section 11 are used as address signals. The color processing in the color processing section 12 also includes the lightness signal V1 and the hue signal H.
1 or the third non-volatile memory 25A of the color processing unit 12 using the chromaticity signal C1 as the address signal.
To the corresponding converted data D11A to
D11C readout is performed by the look-up table method, and the color space inverse conversion process in the color space inverse conversion unit 13 is also performed by the first to third color space inverse conversion units 13 using the synthesized signal S11 as an address signal. Non-volatile memory 28A-2
8C corresponding conversion data D12A to 12
The reading of C is performed by a look-up table method.

Therefore, in the color processing apparatus 10, the supplied digital red signal S1R and digital green signal S1R are supplied.
The color processing for the G and digital blue signals S1B can be performed in substantially real time (processing delay time is fixed and within several frame intervals).

In the color processing apparatus 10, the color space conversion processing, the color processing processing, and the color space reverse conversion processing are performed by a plurality of nonvolatile memories 21A to 21C, 25A to 25A.
C, 28A to 28C, and a look-up table method is used, so that it is possible to easily construct the entire system irrespective of including nonlinear processing.

Further, in the color processing apparatus 10, the nonvolatile memories 21A to 21A for the color space conversion processing and the inverse conversion processing are provided.
1C, 28A to 28C, and the non-volatile memories 25A to 25C for color processing, the rewrite processing of the conversion data when frequently changing the content of the color processing is performed. and 2 ⁸ × 2 ⁸ pieces of conversion data D12A stored in the first nonvolatile memory 25A, the second
2 and ⁸ conversion data D12B stored in the nonvolatile memory 25B, it is only updated with the third stored in non-volatile memory 25C 2 ⁸ × 2 ⁸ conversion data D12c, correspondingly color processing The arithmetic processing of the conversion data D12A to D12C when the processing content is changed,
The rewriting process of 12A to D12C can be performed easily and quickly.

Further, in the color processing apparatus 10, the nonvolatile memories 21A to 21A for the color space conversion processing and the inverse conversion processing are provided.
1C, 28A to 28C, and the non-volatile memories 25A to 25C for color processing, the contents of the color space conversion and inverse conversion processing can be easily changed. Even if a suitable space is proposed, it can be easily and quickly dealt with.

In addition, in the color processing apparatus 10, the first to third nonvolatile memories 21A to 21A of the color space conversion unit 11
Each conversion data D10A to D10C stored in 21C,
First to third nonvolatile memories 28 of the color space inverse conversion unit 13
Conversion data D12A to D12C stored in A to 28C
Can be separated from the operator who actually uses the color processing apparatus 10, so that a small number of former users can use the effective conversion data D10A to D1 based on advanced technical knowledge.
OCC, D12A-D12C can be created so that many latter can easily perform non-linear processing that is difficult to understand.

According to the above configuration, the digital red signal S1R and the digital green signal S1G given from the outside.
The digital blue signal S1B is converted into a lightness signal V1, a hue signal H1 and a chromaticity signal C1 of the uniform visual perception space by a look-up table system in a color space conversion unit 11, and these are processed in a look-up table system in a color processing unit 12. After the nonlinear color processing, the obtained lightness signal V2, hue signal H2, and chromaticity signal C2 are converted to the original digital red signal S3R and digital green signal S by the look-up table method in the color space inverse converter 13.
3G and digital blue signal S3B are inversely converted and output, so that the digital red signal S1R, digital green signal S1G and digital blue signal S1B to be input are color-processed almost in real time while improving usability. Thus, it is possible to realize a color processing system capable of performing complicated non-linear color processing in real time with a simple configuration.

(4) Other Embodiments In the above embodiment, the case where the present invention is applied to the color processing apparatus 1 has been described. However, the present invention is not limited to this, and the present invention is not limited to this. The present invention can be widely applied to various other signal processing devices that perform predetermined signal processing including non-linear processing.

In the above-described embodiment, the non-volatile memory 2 is used as storage means for storing various conversion tables.
1A to 21C, 25A to 25C, and 28A to 28C have been described. However, the present invention is not limited to this, and various other storage means capable of storing a corresponding conversion table can be widely applied. it can.

Further, in the above-described embodiment, the color image signal supplied from outside is the digital red signal S
The present invention has been described in connection with the case where component signals are 1R, a digital green signal S1G, and a digital blue signal S1B (that is, a color space of a color image signal supplied from the outside is a color space representing a color as a combination of three primary colors). However, the present invention is not limited to this, and the color space of a color image signal supplied from the outside may be another color space.

Further, in the above-described embodiment, the actual color processing for the input color image signals S1R, S1G, S1B is performed in a color space in which a color is expressed as a combination of hue, chromaticity and lightness. However, the present invention is not limited to this, and the point is that if color processing is performed in a color space corresponding to human visual characteristics, the color space may be various other color spaces. Can be widely applied.

Further, in the above-described embodiment, the first color image signals (that is, the digital red signal S1R, the digital green signal S1G, and the digital green signal S1G) in the supplied first color space are supplied based on the predetermined first conversion table. The component signal of the digital blue signal S1B) into the hue signal H
1. A case has been described in which the color space conversion unit 11 as a color space conversion means for converting into the chromaticity signal C1 and the lightness signal V1 is configured as shown in FIG. 2, but the present invention is not limited to this. Various other configurations can be widely applied.

Further, in the above-described embodiment, the second color image signal composed of the component signals of the hue signal H1, the chromaticity signal C1, and the lightness signal V1 is converted into the predetermined state based on the predetermined second conversion table. The color processing section 12 as a color processing means for converting into a third color image signal composed of component signals of the hue signal H2, the chromaticity signal C2, and the lightness signal V2, which has been color-processed as shown in FIG. However, the present invention is not limited to this, and various other configurations can be widely applied.

Further, in the above-described embodiment, the hue signal H2 and the chromaticity signal C
The third color image signal composed of the component signals of the second and lightness signals V2 is converted into a fourth color image signal (that is, a digital red signal S1R, a digital green signal S1G, and a digital blue signal) in a color space in which colors are represented by a combination of three primary colors. Although the case where the color space inverse conversion section 13 as the color space inverse conversion means for performing the inverse conversion to S1B) is configured as shown in FIG. 3 has been described, the present invention is not limited to this, and various other configurations are available. Can be widely applied.

Further, in the above embodiment, the actual color processing for the input color image signals S1R, S1G, S1B is performed in the color space of the modified Munsell, which is one of the uniform visual perception spaces. However, the present invention is not limited to this, and various other equivalent visual perception spaces can be widely applied.

[0091]

As described above, according to the present invention, based on the first conversion table, the first color space of the first color space to be supplied is determined.
The color image signal of the predetermined second according to the human visual characteristics
A color space conversion means for sequentially converting the color image into a second color image signal in a color space, and a third color image obtained by subjecting the second color image signal to predetermined non-linear processing based on a second conversion table. A conversion unit for sequentially converting the third color image signal into a fourth color image signal of the first color space based on a third conversion table; By doing so, complicated various nonlinear processing can be performed in real time by the look-up table method using the first to third conversion tables, and the configuration can be simplified. With such a configuration, it is possible to realize a signal processing device capable of performing complicated nonlinear processing in real time.

Further, according to the present invention, based on a predetermined first conversion table, a supplied first color image signal of a first color space is converted to a predetermined second color signal corresponding to human visual characteristics. A third step in which the second color image signal is subjected to predetermined nonlinear processing based on a first step of sequentially converting the space into a second color image signal and a predetermined second conversion table.
A second step of sequentially converting the third color image signal into a fourth color image signal of the first color space based on a predetermined third conversion table. By providing three steps, complicated various nonlinear processing can be performed in real time by the look-up table method using the first to third conversion tables, and thus complicated nonlinear processing can be performed. A signal processing method that can be performed in real time can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an overall configuration of a color processing apparatus according to an embodiment.

FIG. 2 is a block diagram illustrating a configuration of a color space conversion unit and a color processing unit;

FIG. 3 is a block diagram illustrating a configuration of a color space inverse conversion unit.

FIG. 4 is a block diagram showing a configuration of a nonvolatile memory.

FIG. 5 is a block diagram illustrating a configuration example of a color processing apparatus.

[Explanation of symbols]

10: color processing device, 11: color space conversion unit, 12:
Color processing unit 13, 13 Color space inverse conversion unit, 21A to 21
C, 25A to 25C, 28A to 28C: nonvolatile memory, 40: personal computer, 42: CP
U, D10A-D10C, D11A-D11C, D12
A to D12C conversion data S1R, S3R digital red signal S1G, S3G digital green signal S1B, S3B digital blue signal S10
S11 ... combined signal, S20 ... address signal, V1,
V2: brightness signal, H1, H2: color difference signal, C1, C
2. Chromaticity signal.

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁶ Identification symbol FI H04N 9/79 H04N 1/46 Z 9/79 Z (72) Inventor Yuichi Kojima 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (11)

[Claims] A first conversion table storing a predetermined first conversion table;
Based on the first conversion table stored in the first storage means, and converts the supplied first color image signal of the predetermined first color space into human visual characteristics. A color space conversion unit for sequentially converting the image data into a second color image signal in a predetermined second color space in accordance with the second color image signal; and a second storage unit for storing a predetermined second conversion table. Conversion means for sequentially converting the second color image signal into a third color image signal in the second color space, which has been subjected to a predetermined non-linear processing, based on the second conversion table stored in the means And a third storage unit for storing a predetermined third conversion table, wherein the third storage unit outputs the third conversion table based on the third conversion table stored in the third storage unit. Color image signal of the fourth color space of the first color space Signal processing apparatus characterized by comprising a color space inverse conversion means for inversely converting sequential image signal. 2. The signal processing apparatus according to claim 1, wherein said non-linear processing is color processing. 3. The signal processing apparatus according to claim 1, wherein said second color space is a color space in which colors are represented by hue, chromaticity, and lightness. 4. The signal processing apparatus according to claim 1, wherein the second color space is a uniform visual perception space. 5. The signal processing apparatus according to claim 1, wherein said first, second and third storage means store the corresponding first to third conversion tables in a freely changeable manner. apparatus. 6. The conversion means for performing a conversion process of the lightness and the chromaticity on the second color image signal on the basis of the hue based on the second conversion table. The signal processing device according to claim 3. 7. A first color image signal expressed in a predetermined first color space based on a predetermined first conversion table is converted to a first color image signal in a predetermined second color space according to human visual characteristics. A second step for sequentially converting the second color image signal into a second color image signal based on a first step for sequentially converting the second color image signal into a second color image signal based on a predetermined second conversion table; A second step of sequentially converting the third color image signal into a third color image signal, and a reverse conversion of the third color image signal into a fourth color image signal in the first color space based on a predetermined third conversion table. Signal processing method comprising the third step of: 8. The signal processing method according to claim 7, wherein said non-linear processing is color processing. 9. The signal processing method according to claim 7, wherein said second color space is a color space in which colors are represented by hue, chromaticity, and lightness. 10. The signal processing method according to claim 7, wherein said second color space is a uniform visual perception space. 11. In the second step, the brightness and chromaticity conversion processing is performed on the second color image signal based on the hue based on the second conversion table. The signal processing method according to claim 9, wherein: