JPH0530415A - White shading correction processor - Google Patents

Abstract

PURPOSE:To obtain high picture quality with less white shading. CONSTITUTION:A white shading correction quantity corresponding to a zoom position and an iris position respectively based on the information of the zoom position and the iris position outputted from a lens block 11 is processed by an A/D converter 13, a digital process circuit 14 and an MPU 16 and stored in a RAM 17. Then the white shading correction quantity in response to a change in the zoom position and the iris position at a photographing is read from the RAM 17 by the MPU 16 to allow the digital process circuit 14 to implement white shading correction at any time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a white shading correction processing device used in a digital signal processing video camera.

[0002]

2. Description of the Related Art FIG. 2 shows the configuration of a white shading correction processing apparatus in a conventional digital signal processing video camera.

In FIG. 2, 1 is a lens block, and 2 is an image pickup device. The image pickup device 2 receives an optical image from the lens block 1, photoelectrically converts this optical image, and outputs it. Reference numeral 3 is an A / D converter that outputs a digital image pickup signal, 4 is a digital process circuit, 5 is a D / A converter, and 6 is a microprocessor (MPU) that controls the digital process circuit 4. Reference numeral 7 is a RAM, and 8 is an encoder circuit, which outputs a signal processed by the digital process circuit 4.

Next, the operation of the above configuration will be described. In FIG. 2, the optical image incident from the lens block 1 is photoelectrically converted by the image sensor 2, the analog signal is converted into a digital signal by the A / D converter 3, and the digital signal is input to the digital process circuit 4. The digital process circuit 4 processes and corrects various signals, converts it into an analog signal by the D / A converter 5, supplies the analog signal to the encoder circuit 8, and outputs from the encoder circuit 8 as a video output signal to the outside.

The microprocessor 6 controls the state of the digital process circuit 4 and controls various corrections. The RAM 7 writes and reads state values, correction values, etc. for controlling the digital process under the control of the microprocessor circuit 4. In such a conventional white shading correction processing device, in order to correct the light amount drop around the screen that occurs after passing through the color separation optical system of the lens block 1, only one point of data under a certain condition is stored in the RAM 7. It is memorized and read out at the time of shooting to correct white shading.

[0006]

However, the above-described conventional white shading correction processing apparatus can correct only one specific point at the zoom position or the iris position of the lens block 1, and some effects can be expected. However, when the white shading amount changes due to the change of the zoom position and the iris position, there is a drawback that appropriate correction cannot be performed at any time.

The present invention has been made to solve the above-mentioned problems and is capable of performing appropriate white shading correction at any time based on the information on the zoom position and the iris position of a lens block, and is excellent in that a high quality image with little white shading can be obtained. An object of the present invention is to provide a white shading correction processing device.

[0008]

In order to achieve the above object, the white shading correction processing device of the present invention is
A photographing optical system, a lens block for outputting information on the zoom position and the iris position, a detection unit for outputting white shading correction amount information corresponding to the zoom position and the iris position, and a memory for storing the white shading correction amount information. Section, and a correction signal processing means for reading out white shading correction amount information suitable for the change position of the zoom position and the iris position at the time of photographing from the storage part and performing correction processing at any time.

[0009]

Therefore, according to the white shading correction processing apparatus of the present invention, the white shading correction amount information corresponding to each zoom position and iris position is accumulated from the information of the zoom position and the iris position output from the lens block. Then, at the time of shooting, the white shading correction amount information corresponding to the change in the zoom position and the iris position is read out, and the white shading correction is performed at any time, so that a high-quality image with less white shading can be obtained.

[0010]

Embodiments of the white shading correction processing apparatus of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of the embodiment. In FIG. 1, reference numeral 11 denotes a lens block, which includes an imaging optical system and an output unit that outputs zoom position information (signal) and iris position information (signal). 12 is CC
An image sensor such as D receives an optical image from the lens block 11 and photoelectrically converts the optical image to output. 1
3 is an A / D converter, 14 is a digital process circuit,
Reference numeral 16 is a microprocessor (MPU) that controls the digital process circuit 14, and 15 is a D / A converter that converts the signal from the digital process circuit 14 into an analog signal.

Reference numeral 17 is a RAM for accumulating information on the zoom position and the iris position. Reference numeral 18 denotes an encoder circuit, which outputs a signal processed by the digital process circuit 14. Reference numeral 19 is a connection line for sending information on the zoom position and the iris position from the lens block 11.

Next, the operation of the above configuration will be described.
In FIG. 1, information on the zoom position and the iris position from the lens block 11 is input to the A / D converter 13 through the connection line 19. An optical image is incident on the image sensor 12 through the lens block 11, and an electric signal photoelectrically converted therein is input to the A / D converter 13.

The A / D converter 13 converts an analog signal into a digital signal and supplies it to the microprocessor 16. The digital process circuit 14 detects the white shading correction amount based on the information on the zoom position and the iris position from the analog signal from the A / D converter 13, and outputs the correction information to the microprocessor 16
To the RAM 17 through.

Next, at the time of photographing, when the zoom position and the iris position of the lens block 11 are moved, the microprocessor 16 reads from the RAM 17 white shading correction amount information suitable for the information of the zoom position and the iris position.

This reading is performed in response to changes in the zoom position and the iris position at any time during photographing, and the digital process circuit 14 performs white shading correction processing with the white shading correction amount information read in conformity with the changes.

As described above, when the zoom position and the iris position of the lens block are moved at the time of photographing, the white shading correction amount information suitable for the changed position is R
Since it is read from the AM 17 and correction processing is performed by the digital process circuit 14 as needed, high-quality image with less white shading can be obtained.

[0018]

As is apparent from the above description, the white shading correction processing apparatus of the present invention uses the information on the zoom position and the iris position output from the lens block to determine the white corresponding to each zoom position and iris position. It stores the correction information that detects the shading correction amount, reads the white shading correction amount information corresponding to changes in the zoom position and the iris position during shooting, and performs white shading correction at any time. It has an effect that a few high quality images can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a white shading correction processing device of the present invention.

FIG. 2 is a block diagram showing a configuration of a conventional white shading correction processing device.

[Explanation of symbols]

 11 lens block 12 image sensor 13 A / D converter 14 digital process circuit 15 D / A converter 16 MPU 17 RAM 18 encoder circuit 19 connection line

Claims (1)

Claim: What is claimed is: 1. An imaging optical system, a lens block that outputs information about a zoom position and an iris position, and a detection unit that outputs white shading correction amount information corresponding to the zoom position and the iris position. , A storage unit for storing the white shading correction amount information, and white shading correction amount information suitable for the zoom position and the iris position change position at the time of shooting are read from the storage unit, and correction processing is performed at any time. A white shading correction processing device comprising a signal processing means.