JP2001078221A - Image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an image processor capable of easily obtaining desired color reproducibility even when the kind of a light source is changed. SOLUTION: In this image processor, a CPU 5 is provided with a parameter setting circuit 21 that receives an ID signal in response to the kind of a light source from an ID signal generating section 45 of a light source device 4 via a communication means 31. When receiving the ID signal, this parameter setting circuit 21 identifies a type of a lamp 43 of the basis of the ID signal, sets a coefficient for an RGB matrix arithmetic operation as a processing parameter used for the RGB matrix arithmetic operation and outputs the coefficient to an RGB matrix circuit 20. Thus, even when another light source device 4 is used, since a proper RGB matrix arithmetic operation can automatically be conducted, the desired color reproducibility can easily be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus, and more particularly, to an image processing apparatus capable of performing color reproducibility regardless of the type of light source.

[0002]

2. Description of the Related Art Conventionally, an image pickup apparatus provided with an image processing apparatus for performing signal processing on an image pickup signal obtained by photoelectrically converting a subject image has been used.
It is widely used in the fields of V cameras, electronic endoscopes and the like.
The image processing device used in such an imaging device,
A luminance signal and a chrominance signal obtained from a solid-state imaging device such as a CCD are converted into a uniquely defined matrix (hereinafter, referred to as a matrix) including predetermined coefficients.
An arithmetic process is performed using an RGB matrix, and R
After being converted into a GB digital signal, it is displayed on a display screen such as a monitor.

Generally, in an image processing apparatus, various adjustments such as a white balance adjustment and a black balance adjustment are performed in order to eliminate variations due to a difference in a light source device to be used and to realize good color reproducibility. However, in endoscopic diagnosis, the observation site or xenon,
Since the desired color reproduction differs depending on the type of light source used, such as halogen, the desired color reproducibility can be obtained by using only a uniquely defined RGB matrix irrespective of the observation site and the type of light source device used. It was difficult to realize.

On the other hand, for example, an image processing apparatus described in Japanese Patent Application No. 11-027354 filed by the present applicant prepares a plurality of types of RGB matrices and uses, for example, xenon, metal halide, halogen, or the like. There has been proposed a device in which a user can select an appropriate RGB matrix according to the type of light source to be used.

[0005]

However, in the image processing apparatus described in Japanese Patent Application No. 11-027354,
When performing an endoscope diagnosis by switching the light source to be used, it is necessary for the user to set an appropriate RGB matrix again and switch each time the type of the light source changes, so that there is a problem that it is difficult to use.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an image processing apparatus capable of easily obtaining a desired color reproducibility even when the type of a light source is changed. .

[0007]

According to a first aspect of the present invention, there is provided an image processing apparatus comprising: an image processing apparatus configured to convert an imaging signal obtained by photoelectrically converting a subject image illuminated by illumination light from a light source into a predetermined processing parameter; Signal processing means for performing signal processing based on, and input an identification signal corresponding to the type of the light source,
Parameter setting means for setting the processing parameters of the signal processing means based on the identification signal. According to a second aspect of the present invention, in the image processing apparatus according to the first aspect, the processing parameter is a coefficient used for an RGB matrix operation. With this configuration, it is possible to easily obtain desired color reproducibility even when the type of the light source is changed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 to 5 relate to an embodiment of the present invention, FIG. 1 is a configuration diagram showing a configuration of an endoscope imaging apparatus according to an embodiment of the present invention, and FIG. 2 is an embodiment of the present invention. FIG. 3 is a block diagram showing the configuration of the RGB matrix circuit of FIG. 2, FIG. 4 is a block diagram showing the configuration of the parameter setting circuit of FIG. 2, and FIG. 5 is a flowchart illustrating an operation of a setting circuit.

As shown in FIG. 1, an endoscope imaging apparatus 1 includes a camera head 2 having built-in imaging means, a scope 3 to which the camera head 2 is detachably connected, and illumination light supplied to the scope 3. A light source device 4, a camera control unit (hereinafter abbreviated as CCU) 5 as an image processing device for performing signal processing on an image signal obtained by an image pickup means provided in the camera head 2, CCU5
For displaying a standard video signal processed by the
A monitor 6 is provided.

The scope 3 is, for example, an optical endoscope having an insertion section 7 for inserting an image guide fiber (not shown) for transmitting an endoscope image which is elongated and flexible. The camera head 2 is detachably connected to the eyepiece of the operation unit 8 provided at the base end of the insertion unit 7 via the adapter 2a, so that the eyepiece of the operation unit 8 is connected to the image guide fiber (not shown). The endoscope image transmitted to the section can be captured by the camera head 2. A light guide cable 9 extends from the operation unit 8 of the scope 3. By connecting the distal end of the light guide cable 9 to the light source device 4, illumination light supplied from the light source device 4 is transmitted to the light guide cable 9. And a light guide fiber (not shown) penetrating through the insertion portion 7 to make the scope 3
A subject (not shown) is illuminated from the tip of the camera. Then, the reflected light of the subject illuminated by the illumination light is imaged by the scope 3, and an image of the subject is taken by the imaging means in the camera head 2 through the scope 3.

On the other hand, in the camera head 2, a CCD 11 as an image pickup means is disposed on a focal plane of an image pickup lens (see FIG. 2), and a subject image is formed on the image pickup surface of the CCD 11 and photoelectrically converted. . The CCD 11 is connected to the CCU 5 via a camera cable 12 extending from the camera head 2 in which a CCD drive signal transmission line and a CCD output signal transmission line are inserted, and an output signal of the CCD 11 is sent to the CCU 5. Various signal processing is performed. The video signal output from the CCU 5 is sent to the TV monitor 6, and an observation image of the subject is displayed on the TV monitor 6.

As shown in FIG. 2, the CCU 5 includes a CC
A CCD driver 13 for driving and controlling the D11 is provided, and a CCD driving signal is transmitted from the CCD driver 13 via a CCD driving signal transmission line in the camera cable 12.
Signal charge supplied to the CCD 11 and stored in the CCD 11
Read as a CD output signal. The CCD output signal read from the CCD 11 is amplified by the preamplifier 14, transmitted to the CCU 5 via the CCD output signal transmission line in the camera cable 12, and input to the pre-processing circuit 15 in the CCU 5.

An A / D converter is provided after the pre-processing circuit 15.
A conversion circuit 16 and a Y / C separation circuit 17 are provided. The CCD output signal input to the pre-processing circuit 15 is subjected to pre-processing such as CDS (correlated double sampling) and S / H (sample hold). After that, the A / D conversion circuit 1
After being input to 6 and converted into a digital signal, it is input to the Y / C separation circuit 17. A color difference LPF (low pass filter) 18 and a line-sequential synchronization circuit 19 are provided downstream of the Y / C separation circuit 17.
7 is separated into a luminance signal Y and a chroma signal C. The chroma signal C is subjected to line-sequencing by a line-sequential synchronizing circuit 19 after a pseudo-color or the like is removed by a color difference LPF 18, and Y · Three digital signals of CR and CB are output.

In the subsequent stage of the line-sequential synchronization circuit 19, RGB
A matrix circuit 20 is provided.
The signals are converted into RGB digital signals by multiplying and adding coefficients used in a 3 × 3 RGB matrix operation as processing parameters to the three digital signals of CR and CB.

In the present embodiment, when converting the digital signals of the three systems of Y, CR, and CB into RGB digital signals, an identification signal corresponding to the type of the light source is input by a parameter setting circuit 21 described later. , And the coefficients used for the RGB matrix operation are set.

In the subsequent stage of the RGB matrix circuit 20,
A W / B circuit 22 and a γ correction circuit 23 are provided,
RG generated by the RGB matrix circuit 20
The B signal is white-balanced by the W / B circuit 22 and subjected to γ correction by the γ correction circuit 23,
The D / A conversion is performed by the / A converter 24, and the composite signal VBS and the RGB signal are generated by the encoder 25 and output to a monitor (not shown).

Further, the CCU 5 is provided with a reference signal generation circuit (hereinafter abbreviated as SSG) 26.
A timing signal generation circuit (hereinafter abbreviated as TG) 27 generates various timing signals to the above-mentioned various circuits based on the reference clock signal generated from 26.

Further, the CCU 5 is provided with a detection circuit 28 for detecting the brightness of the image from the RGB digital signal from the RGB matrix circuit 20, and the detection output of the detection circuit 28 is output to the CPU 29,
It is determined whether the brightness of the image is equal to or more than a predetermined value, and a setting signal and a control signal are output to an exposure control circuit (not shown) and the CCD driver 13 based on the value of the brightness of the image.

The light source device 4 controls the lamp 43 as a light source based on a reference clock signal generated from a reference signal generating circuit (hereinafter abbreviated as SG) 41, thereby illuminating the lamp 43. The light passes through the stop 44, is condensed by a lens (not shown), and is emitted to the light guide fiber of the endoscope. The light source device 4 outputs an ID signal as an identification signal from the ID signal generator 45 to the parameter setting circuit 21 in the CCU 5 via the communication means 31 based on the reference clock signal of the SG 41. . The communication means 31 uses, for example, an interface standardized by IEEE (for example, IEEE1394), a standard such as Ethernet, or a digital communication means such as USB or RS-232c.

The light source device 4 is different for each type of lamp 43 such as xenon, metal halide and halogen. The ID signal generator 45 has an ID signal set according to the type of lamp 43. It should be noted that different lamps 43 may be exchanged for each type in the same light source device 4 and an ID signal corresponding to the type of the lamp 43 may be set in the ID signal generator 45.

In the configuration described above, in the present embodiment, in particular, the coefficients used for the RGB matrix calculation in the RGB matrix circuit 20 are automatically determined based on the ID signal input through the communication means 31. It is configured to be set dynamically.

Hereinafter, this embodiment will be described in detail with reference to FIGS. First, the RGB matrix circuit will be described. As shown in FIG. 3, the RGB matrix circuit 20 includes, for example, a CPU interface 51 that receives an input from the parameter setting circuit 21,
A coefficient register 52 for holding coefficients relating to the RGB matrix transmitted from the U interface 51;
/ C separation circuit 17 and an input register 50 for holding a signal, and multipliers 53a to 53i and adders 54a to 54c for performing a predetermined RGB matrix operation based on the coefficient held in the coefficient register 52 And an output register 53 for holding the same.

According to this configuration, an RGB matrix operation represented by the following equation is realized.

[0024]

(Equation 1) For the RGB matrix calculation, coefficients used in the RGB matrix calculation as processing parameters corresponding to the type of the lamp 43 used, such as xenon, metal halide, or halogen, are given by, for example, the following matrix coefficients.

[0025]

[Table 1] The parameters of these RGB matrix calculations are set by the parameter setting circuit 21 by inputting the ID signal of the light source device 4. It should be noted that a lamp other than xenon, metal halide, and halogen may be used as a light source and RGB matrix calculation coefficients corresponding to the lamp may be set.

As shown in FIG. 4, the parameter setting circuit 21 includes, for example, a CPU 61, a ROM 62, a RAM 6
3, an MPU composed of a serial port 64 and a parallel port 65, which rewrites the coefficients of the RGB matrix operation equation using a bus line of an address bus 21a and a data bus 21b in accordance with a coefficient setting flow described later.

The operation of the present embodiment thus configured will be described. Inserting the insertion portion 7 of the scope 3 into the body cavity, supplying illumination light from the light source device 4 to the scope 3,
The endoscope image transmitted to the eyepiece is transferred to the CCD of the camera head 2.
An image is taken at 11. The CCU 5 processes the image signal and displays an endoscope image on a monitor (not shown). Here, when the light source device 4 is changed, an ID signal from the ID signal generation unit 45 in the light source device 4 is output to the parameter setting circuit 21 in the CCU 5 via the communication unit 31.

ID input to parameter setting circuit 21
The signals are supplied to the address bus 21a under the control of the CPU 61,
The data is read into the RAM 63 via the data bus 21b (step S1) and compared with the ID stored in the ROM 62. For example, if the changed lamp 43 of the light source device 4 is a xenon lamp, the CPU 61 determines whether or not ID = 1. Is identified (step 2), and when ID = 1, the matrix coefficient A described in, for example, Table 1 stored in the ROM 62 is written in the RAM 63 (step S3), and RGB is transmitted via the address bus 21a and the data bus 21b. The data is output to the matrix circuit 20, and the operation of coefficient setting is completed (step S4).

If the lamp 43 of the changed light source device 4 is a metal halide lamp, it is determined whether ID = 2 or not.
PU 61 identifies (step 5), and when ID = 2, R
For example, the matrix coefficient B stored in the OM 62 is written into the RAM 63 (step S6), output to the RGB matrix circuit 20, and the coefficient setting operation ends (step S4). On the other hand, if the changed lamp 43 of the light source device 4 is a halogen lamp (ID = 3), for example, the matrix coefficient C is written in the RAM 63 (step S7), output to the RGB matrix circuit 20, and the coefficient setting operation ends. (Step S4).

Then, based on the output coefficients, RG
A predetermined RGB matrix operation is performed in the B matrix circuit 20, and the three digital signals of Y, CR, and CB are converted into RGB digital signals according to the type of the lamp 43 used, such as xenon, metal halide, and halogen.

As a result, even when the type of the light source is changed,
It is possible to easily obtain desired color reproducibility.

In the present embodiment, the scope 3 is an optical endoscope provided with the insertion section 7 having a built-in image guide fiber. However, the scope 3 is not limited to this. It is needless to say that an endoscope or an electronic endoscope provided with a solid-state imaging device in the distal end portion of the insertion portion which does not require the use of the camera head 2 can obtain the same operation and effect.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the present invention.

[Supplementary note] (Supplementary note 1) Signal processing means for subjecting an image signal obtained by photoelectrically converting a subject image illuminated by illumination light from a light source to signal processing based on predetermined processing parameters, and corresponding to the type of the light source An image processing apparatus, comprising: a parameter setting unit that receives an identification signal and sets the processing parameter of the signal processing unit according to the light source.

(Appendix 2) The processing parameter is R
2. The image processing apparatus according to claim 1, wherein the coefficient is a coefficient used for a GB matrix operation.

(Additional Item 3) The image processing apparatus according to additional item 2, wherein the light source is different for each type of light source lamp that emits illumination light.

(Additional Item 4) The image processing apparatus according to additional items 1 to 3, wherein the parameter setting means communicates the identification signal by digital communication means.

[0038]

As described above, according to the image processing apparatus of the present invention, even when the type of the light source is changed, an appropriate RGB matrix operation can be automatically performed according to the type of the light source. There is an effect that color reproducibility can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of an endoscope imaging apparatus according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a configuration of a CCU provided with one embodiment of the present invention.

FIG. 3 is a circuit block diagram showing a configuration of an RGB matrix circuit of FIG. 2;

FIG. 4 is a circuit block diagram showing a configuration of a parameter setting circuit of FIG. 2;

FIG. 5 is a flowchart illustrating the operation of the parameter setting circuit of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope imaging device 2 ... Camera head 2a ... Adapter 3 ... Scope 4 ... Light source device 5 ... CCU (image processing device) 6 ... TV monitor 11 ... CCD 20 ... RGB matrix circuit 21 ... Parameter setting circuit (parameter setting means) 21a ... data bus 21b ... address bus 31 ... communication means (digital communication means) 45 ... ID signal generator 61 ... CPU 62 ... ROM 63 ... RAM 64 ... parallel port 65 ... serial port

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 9/04 G06F 15/62 390Z 5C066 (72) Inventor Akihiko Mochida 2-43-2 Hatagaya, Shibuya-ku, Tokyo No. Olympus Optical Co., Ltd. (72) Inventor Makoto Tsunakawa 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Hideki Tashiro 2-43-2, Hatagaya, Shibuya-ku, Tokyo No. Olympus Optical Co., Ltd. (72) Inventor Noboru Kusamura 2-43-2 Hatagaya, Shibuya-ku, Tokyo F-term within Olympus Optical Co., Ltd. 2H040 CA04 GA01 GA05 4C061 AA00 BB01 CC06 DD00 JJ18 LL00 MM02 NN05 TT04 5B057 AA07 BA02 CE06 CE17 CE18 5C054 AA01 AA05 CA04 CB02 CC07 EA01 EB05 EB07 ED07 ED13 EE04 EE06 EF01 EF02 FA 01 FB04 HA12 5C065 AA04 BB01 CC02 CC03 CC09 DD02 DD17 EE03 EE12 FF07 GG12 GG15 GG18 GG21 GG23 GG32 GG35 5C066 AA01 BA20 CA17 DC06 DD07 DD08 EA13 EA14 EC01 EC05 EE03 GA01 GA02 KE02 KE02 KE02 KE02 KE02 KE03

Claims (2)

[Claims] 1. A signal processing means for performing signal processing on an imaging signal obtained by photoelectrically converting a subject image illuminated by illumination light from a light source based on a predetermined processing parameter; and an identification signal corresponding to a type of the light source; An image processing apparatus comprising: a parameter setting unit configured to set the processing parameter of the signal processing unit based on the identification signal. 2. The image processing apparatus according to claim 1, wherein the processing parameter is a coefficient used for an RGB matrix operation.