JPH0918790A - Camera equipment - Google Patents

Abstract

PURPOSE: To obtain a beautiful video image without defects apparently by adding the position of an image defect of an image pickup element as auxiliary information and allowing a signal processing section to supplement data of the picture element defect based on the added information. CONSTITUTION: The equipment is provided with an addition means adding a position of a picture element defect of a CCD 101 for each line to a digital video signal from a camera head section as auxiliary information and a means using a signal processing section to compensate data of the picture element defect based on the information added by the additional means. Then a position and a number (N) for each line of the picture element defect of the CCD 101 are recorded in a storage means 11. A number N of the picture element defect in the line is read from the storage means 11 by an ADR generating section 12. The ADR generating section 12 generates an address output signal ADR representing an output period of address data. An OR section 14 generates a BLK signal rising faster by (N+1) clocks than the CBLK from the ADR and CBLK signal. The CBLK signal is a signal denoting the effective area of the image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera device used as an image input device such as a personal computer or a workstation.

[0002]

2. Description of the Related Art Recently, it has come to be noticed that a camera is connected to a computer system to hold a video conference and to be applied to edit an image captured by the camera. A digital camera that can obtain digital image data has been attracting attention because of its good signal compatibility with a computer system.

An example of such a digital camera is shown in FIG.
Shown in In FIG. 8, reference numeral 100 denotes a camera head portion, 10
1 is a CCD unit (imaging device), 102 is a drive circuit, 103
Is a CDS (correlated double sampling) circuit / AGC (automatic gain control) circuit, 104 is an ADC (analog-digital conversion) circuit, 105 is a transmission circuit, 200 is a computer system, 201 is an I / F unit, 202 is a main memory, Two
Reference numeral 03 is a CPU.

In the digital camera shown in FIG. 8, incident light is converted into an electric signal by the CCD 101, and the CDS
After being processed by the circuit / AGC circuit 103, it is converted into digital data by the ADC circuit 104, a synchronization signal is added to the video data by the transmission circuit 105, and a bit string is output.

FIG. 10 shows how one screen of image data having the CCD filter structure shown in FIG. 9 is transmitted. In FIG. 9, the CBLK signal is a signal indicating the effective image data area in all the image data, and is the transmission circuit 105.
Transmits the image data of this effective area. Transmission circuit 1
05 indicates the start of the effective area for each horizontal line SS
The YN signal and the sync signal of the ESYN signal indicating the end of the effective area are added and transmitted. Here, the image data is parallel, but in order to reduce the number of wires, the transfer rate may be increased and serial transmission may be performed.

In the computer system, the I / F unit 20
Input the bit string from the camera head 100 with 1,
The data is input to the main memory 202 by being mounted on an expansion bus such as a PCI bus. The CPU 203 performs calculation to obtain a luminance signal Y and color difference signals R-Y and B-Y. At this time, it is possible to obtain a sharp image with less noise by performing S / N improvement utilizing line correlation and correction such as edge enhancement.

[0007]

In the digital camera constructed as described above, the image pickup element often has pixels that cannot be converted into electric signals from the image pickup light. Since this is a manufacturing defect, it is difficult to completely eliminate it. If the image pickup element has a pixel defect in this way, the video signal in the vicinity thereof will not have a correct value. In order to correct this pixel defect, the signals before and after the pixel defect are replaced, so the position of the pixel defect is required.

Usually, as disclosed in Japanese Patent Laid-Open No. 6-112236, this is realized by storing the position of the pixel defect of the image pickup device in a storage means such as a memory and reading it out. Is different for each image pickup device, so in a head-separated camera, when the camera head is replaced or the images of a plurality of camera heads are switched and processed, the data in the storage means provided in the signal processing unit is replaced each time. Alternatively, it is necessary to prepare a signal line for sending data to the signal processing unit by providing the camera head unit with storage means.

Further, since the obtained image has a shape of a medium bulge due to the aberration of the lens, it is disclosed in JP-A-62-8118.
No. 0, JP-A-62-230267, etc., a method for correcting distortion by the lens is provided, but in a configuration in which the camera head section and the signal processing section are separated from each other, When the camera head is replaced, the lens is also replaced, so it is necessary to change the data used for correction.

Further, in the S / N improvement by the line correlation,
The contour in the vertical direction is blurred, so that contour enhancement is performed. However, when the level of the input signal is amplified by AGC, the S / N ratio is usually poor. If contour enhancement is performed in such a case, it is included in the signal. The random noise generated is emphasized, and the S / N ratio is further deteriorated.

As disclosed in Japanese Patent Publication No. 5-16708, there is a method of controlling the strength of the contour enhancement and the S / N improving action by the gain level of AGC, which is realized by a head separation type camera. Attempting to do so requires a signal line for transmitting a continuously changing AGC level to the signal processing unit.

[0012]

A camera device according to the present invention solves the above problems. In the invention according to claim 1, a digital video signal from a camera head unit is provided for each line as auxiliary information. Further, it is provided with an adding means for adding the position of the pixel defect of the image pickup device, and a means for compensating the data of the pixel defect in the signal processing unit based on the information added by the adding means.

In addition, in the invention described in claim 2, the addition means of the invention described in claim 1 stores the position and the number of the pixel defect of each line of the image pickup element for each line, and the storage means for each line. Line data adding means for adding the position data of the pixel defect of the line to the horizontal blanking period of the video signal, and the invention according to claim 3 provides the invention according to claim 2 above. The line data adding means includes an ADR generation section and an OR section.

Further, in the invention according to claim 4,
It is provided with a storage means for storing auxiliary information, an initial data addition means for adding the information to the video signal in the vertical blanking period at the time of initialization, and a transmission means for sending the video signal including the initial setting data. .

Furthermore, in the present invention as defined in claim 5, an A / D converter for converting the gain level of the AGC into digital data, a data adding means for adding information in the vertical blanking period, and a video signal for adding an auxiliary signal are transmitted. The transmission means is provided.

[0016]

According to the present invention, there is provided a camera device having the above structure.
According to the third aspect of the invention, the information indicating the position of the pixel defect of the image sensor is added to each line and transmitted. According to the fourth aspect of the invention, information on image distortion due to the lens used in the camera head is added and transmitted at the time of initialization. Then, in the invention according to claim 5, the information about the gain of the AGC is added and transmitted.

[0017]

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

First, a first embodiment of the camera device of the present invention will be described with reference to FIGS. 1 to 3. The CCD unit 101, the drive circuit 102, the CDS / CDS /
AGC circuit 103, ADC circuit 104, transmission circuit 105
The description of the configuration and operation of is omitted.

In FIG. 1, the storage means 11 records the position (address data) and the number (N) of each pixel defect of the image pickup device for each line. As shown in FIG. 9, the addresses are 1, 2, 3, ...
Is assigned, indicating which pixel from the beginning of the data is the defective pixel.

First, the storage means 11 to the ADR generator 12
Then, the number N of pixel defects on that line is read. A
The DR generator 12 generates an address output signal ADR indicating the output period of the address data. In the OR section 14, AD
From the R and CBLK signals, a BLK signal having an N + 1 clock rising edge faster than that of CBLK as shown in FIG. 2 is generated. The CBLK signal is a signal indicating the effective area of the image. The timing of these pulses is shown in FIG.

For example, if there are n defective pixels in a certain line, the data N read from the storage means 11 will be described.
= N is input to the ADR generation unit 12. The ADR generator is composed of a counter and a decoder, and the counter is a CB.
The BK pulse resets CBLK during the "H" period.

As shown in FIG. 2, it is assumed that the CBLK pulse rises and M clocks rise (MFCK).
It depends on the driving method of CCD), and the ADR signal is C
From the falling edge of BLK (release of reset) to M- (n +
1) It is generated so that it rises at the clock and falls at the rise of CBLK.

The multiplexer unit 13 outputs the image data while the ADR signal is "L", and sequentially outputs the address data when the ADR signal becomes "H". The signal PDO output from the multiplexer unit 13 is in a format in which the data N of the defective pixel number is added n + 1 clocks before the image data PDI and n address data is sequentially added from the clock n clocks before. Further, the transmission circuit 105 outputs image data while the BLK signal is “H”. The data format output from the transmission circuit 105 is shown in FIG.

In FIG. 3, SSYN and ESYN are timing reference signals indicating horizontal and vertical synchronization of images. For example, if only the pixels marked with * in FIG. 9 are defective pixels on the first line, the output signals on the first line are SSYN, 1 , 3 , C4 ₁ , C3 ₁ , * C4 ₂ , C3 ₂ , ..., ESYN N Adress It becomes a video signal. Since the BLK signal is at the “H” level while the number of data N, the address data and the effective image data are being output, the data string as shown in FIG. 3 is output by the transmitting circuit.

In the above-mentioned first embodiment, the case where the transmission circuit carries out parallel transmission has been shown, but it may also carry out serial transmission. The data string thus transmitted is received by the personal computer system and is corrected based on the data.

For example, when the pixel at the address m on a certain line is defective, the output signal of the image pickup device having a complementary color filter is C1, C2, C1, as shown in FIG.
C2, C1 ..., or C4, C3, C4, C3 ..
.., the m-th data D _m is the output of the same filter as the defective pixel and the m-th data D _m-2 and m +.
From the second data D _{m + 2}

[0027]

[Equation 1]

Is obtained as This calculation is for a case where the filter array is of a complementary color system, and the data used for calculation also changes if the filter array or driving method of the image sensor changes.

Next, a second embodiment of the camera device of the present invention will be described with reference to FIGS. 4 to 6. Similar to the first embodiment, the CCD section 101, the drive circuit 102, which are the same parts as the conventional example, CDS / AGC circuit 103, ADC circuit 10
4. The description of the configuration and operation of the transmission circuit 105 will be omitted.

In FIG. 4, the storage means 21 stores information about image distortion due to the lens mounted on the camera head. The storage means 21 detects the start of a line by the horizontal reference signal HD, reads the data of the line, and outputs it as the data PT.

The CBLK signal is a pulse indicating the effective area of the image, and is a 1CKDLY section 22, an AND section 23, and an OR section 2.
4, pulse, SW signal and CBL shown in FIG.
A KO signal is created. The multiplexer unit 25 is a SW
Image data is output while the signal is "L", and data PT is output when the SW signal is "H". Image data PD
Since I is a signal delayed by one pixel by 1CKDL24, the signal PDO output from the multiplexer unit 25 has a format in which the data PT is added one clock before the image data PDI.

Since the CBLKO signal is at "H" level while the data PT and the effective image data are being output, the data circuit as shown in FIG. 5 is output by the transmitting circuit 105. In the personal computer system, the image signal is corrected based on the received data PT to remove the image distortion due to the lens. In the above-described second embodiment, the case where the transmission circuit 105 performs parallel transmission has been shown, but it may also be the case of serial transmission.

Next, a third embodiment of the camera device of the present invention will be described mainly with reference to FIG. 7. Similar to the embodiment 1 above,
The CCD unit 101 and the drive circuit 10 which are the same as those of the conventional example
2, the description of the configurations and operations of the CDS / AGC circuit 103, the ADC circuit 104, and the transmission circuit 105 will be omitted.

In FIG. 7, the gain level of the AGC section is converted to digital data by the ADC2 section 31, the data is held for each horizontal line by the flip-flop 37, and it is combined with the dummy data into a 10-bit Gain signal. . The CBLK signal is a pulse indicating the effective area of the image,
The 1CKDLY unit 32, the AND unit 33, and the OR unit 34 generate the pulse, the SW signal, and the CBLKO signal shown in FIG.

The multiplexer section 36 outputs image data while the SW signal is "L", and the SW signal is "H".
Then, the Gain signal is output. Image data PDI
Is a signal delayed by one pixel by 1CKDL35, the signal PDO output from the multiplexer unit 36 is the Gain signal one clock before the image data PDI.
The signal is added.

Since the CBLKO signal is at the "H" level while the Gain signal and the effective image data are being output, a data string as shown in FIG. 5 is output by the transmitting circuit 105. In the personal computer system, when the gain signal in the AGC is large, that is, when the S / N ratio is poor, the contour emphasis is weakened from the gain signal of the received data string to reduce the S / N ratio.
Control to strengthen improvement.

By doing so, it is possible to minimize the contradictory side effects of the contour enhancement and the S / N improvement utilizing the line correlation. In the above third embodiment, the case where the transmission circuit performs parallel transmission has been shown, but it may also be the case of serial transmission.

[0038]

Since the camera device of the present invention has the above-mentioned structure, in the invention described in claims 1 to 3, it is apparent that the data of the pixel defect generated at the time of manufacturing the image pickup device is supplemented. It is possible to obtain a clean image without any defects, and it is possible to always make corrections without adjustment even when the camera head is replaced or the image sensor is changed by switching, and even in that case, a dedicated signal line is required. do not do.

According to the fourth aspect of the invention, the image distortion due to the lens can be corrected without the need for adjustment even when the camera head is replaced. And
According to the fifth aspect of the present invention, contour enhancement with less deterioration of the S / N ratio can be realized in a head separation type camera without using a dedicated signal line.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a camera device of the present invention.

FIG. 2 is a timing chart of each pulse and image data in the first embodiment of the camera device of the present invention.

FIG. 3 is an explanatory diagram of a data string output in the first embodiment of the camera device of the present invention.

FIG. 4 is a block diagram showing a second embodiment of the camera device of the present invention.

FIG. 5 is a timing chart of each pulse and image data according to the second or third embodiment of the camera device of the present invention.

FIG. 6 is an explanatory diagram of a data string output in the second embodiment or the third embodiment of the camera device of the present invention.

FIG. 7 is a block diagram showing a third embodiment of the camera device of the present invention.

FIG. 8 is a block diagram showing an embodiment of a conventional camera device.

FIG. 9 is an explanatory diagram of a CCD filter array.

FIG. 10 is an explanatory diagram of a data string output in the embodiment of the conventional camera device.

[Explanation of symbols]

11, 21 storage means 12 ADR signal generation section 13, 25, 36 multiplexer section 14, 24, 34 OR section 22, 26, 32, 35 1 clock delay section 23, 33 AND section 31, 104 A / D converter 37 flip-flop 100 camera head section 101 image sensor 102 image sensor drive circuit 103 sample hold / AGC circuit 104 ADC circuit 105 transmission circuit 200 computer system 201 interface section 202 main memory 203 CPU or signal processing circuit

Claims (5)

[Claims] 1. A signal separated from a camera head section for converting an output signal from an image sensor into a digital signal and outputting it as a digital video signal, and a camera head section for processing the digital video signal from the camera head section. In a head-separated type camera device including a processing unit, an addition unit that adds a pixel defect position of an image sensor for each line as auxiliary information to a digital video signal from the camera head unit and the addition unit. A camera device, comprising means for compensating the pixel defect data in a signal processing unit based on the added information. 2. The storage means in which the adding means stores the position and the number of each pixel defect of the image pickup device for each line, and the position data of the pixel defect of the line for each line in the horizontal blanking period of the video signal. The camera device according to claim 1, further comprising line data adding means for adding the line data. 3. The line data adding means comprises an ADR generation section and an OR section.
The described camera device. 4. A signal separated from a camera head section for converting an output signal from an image pickup device into a digital signal and outputting it as a digital video signal and a camera head section for processing the digital video signal from the camera head section. In a head-separated type camera device including a processing unit, means for adding distortion information due to the lens of the camera head to the digital video signal as auxiliary information, and correcting the distortion in the signal processing unit based on the information. A camera device comprising: 5. A signal separated from a camera head section for converting an output signal from an image pickup device into a digital signal and outputting it as a digital video signal, and a camera head section for processing the digital video signal from the camera head section. In a head-separated camera device including a processing unit, an AGC (automatic gain control) gain is added to the digital video signal as auxiliary information, and the signal processing unit improves S / N and enhances contour according to the gain level. A camera device comprising means for controlling the above process.