JP3227769B2 - TV intercom - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television intercom capable of capturing an image of a visitor's face with a television camera at an entrance, a gate, or the like of an ordinary household, and monitoring the interior of the house.

[0002]

2. Description of the Related Art Conventionally, this type of television intercom has
It consists of a child device with a built-in TV camera installed at the entrance, gate, etc. of ordinary households, and a parent device with a monitor installed inside the house, taking a visitor standing in front of the entrance with a TV camera, The image signal is sent to the parent device, and the family member (user) confirms the visitor.

[0003] In such a television intercom, the imaging range is about 60 degrees in the horizontal angle and about 45 degrees in the vertical angle, and if the height or movement of the customer is high, the user cannot see the desired part. There were drawbacks.

Therefore, it is conceivable to widen the image pickup range by widening the lens of the television camera.
As shown in FIG. 3, there is a problem that the image is deformed due to lens distortion caused by the wide-angle lens and the screen becomes difficult to see.

In order to solve the above problem, in order to correct lens distortion of the wide-angle lens, an image signal taken from a slave unit is temporarily stored as a digital signal, and the distortion characteristic of the wide-angle lens is corrected. There is a method in which the horizontal and vertical address conversion tables are prepared, the addresses are converted, and then displayed on a monitor to eliminate lens distortion.

[0006]

However, in the above method, after storing the entire screen once in the field memory,
Since the horizontal and vertical addresses of each pixel are converted, a complicated and expensive correction process is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to correct distortion of an imaging lens with a simple and inexpensive configuration even when a wide-angle lens is used as the imaging lens. Another object of the present invention is to provide a television interphone that obtains an easily viewable image.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a slave unit for capturing an image of a visitor or the like by an imaging unit and outputting an image signal, and a master unit for capturing an image signal output from the slave unit and displaying the image signal on a monitor. A television intercom, wherein the imaging unit includes a one-dimensional wide-angle lens that is wide-angle in a one-dimensional direction,
The parent device has a line memory that stores only one-dimensional image signals output from the child device, a distortion correction unit that corrects one-dimensional distortion, and a distortion correction device that stores data for the distortion correction. It is characterized by having a table.

[0009]

In the television intercom of the present invention, a one-dimensional wide-angle lens having a wide-angle characteristic only in one-dimensional direction is used as a wide-angle lens included in the imaging means, and the distortion correction table of the parent device has a central axis of distortion. The correction amount determined by the distance from the camera is stored as data, and the distortion correction processing means corrects the one-dimensional distortion using this correction data.

[0010]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. Reference numeral 1 denotes a child device installed at an entrance, a gate, or the like of a general household or the like, which images a visitor and outputs an image signal thereof.

Reference numeral 11 denotes an image pickup means such as a television camera for picking up an image of a visitor. Reference numeral 12 denotes a one-dimensional wide-angle lens for picking up a wide-angle image only in a one-dimensional direction (for example, a horizontal direction) of an image pickup field.

Reference numeral 2 denotes a master unit installed in the house, which captures an image signal output from the slave unit 1 and monitors an image.

An A / D converter 21 converts an image signal from the slave 1 into digital data.

A line memory 22 stores image data for each line in the horizontal direction.

Reference numeral 23 denotes a distortion correction table for storing data for distortion correction. When the one-dimensional wide-angle lens 12 is used, as shown in FIG. Using the characteristic that the amount of distortion is determined, the amount of distortion correction corresponding to the distance from the center axis C of the distortion is stored as data.

Numeral 24 denotes a distortion correction processing means, which fetches distortion correction data from a distortion correction table 23 based on the distance of the image data output from the line memory 22 from the central axis C to perform distortion correction.

Reference numeral 25 denotes D / A conversion means for converting the image data after the distortion correction output from the distortion correction processing means 24 into an analog signal.

Reference numeral 26 denotes a monitor which displays an analog signal output from the D / A conversion means 25 as an image.

Here, whether the one-dimensional wide-angle lens 12 performs wide-angle imaging in the horizontal direction or wide-angle imaging in the vertical direction may be determined according to the specifications. That is, for example, a tall object to be imaged is tall. If you want to image both adults and short children, you can use a wide-angle lens in the vertical direction.If you want to image all people when multiple people of the same height stand side by side in the horizontal direction It suffices to use a lens that has a wide angle in the horizontal direction.

When a one-dimensional wide-angle lens 12 is used in combination with a horizontally wide-angle lens and a vertically wide-angle lens, a two-dimensional wide-angle image can be obtained without distortion.

[0022]

As described above, according to the television intercom of the present invention, a one-dimensional wide-angle lens having a wide-angle characteristic only in one-dimensional direction is used as a wide-angle lens included in the image pickup means, and a distortion correction table for the parent device is used. The correction amount determined by the distance from the center axis of the distortion is stored as data, and the distortion correction processing means corrects the one-dimensional distortion using this correction data. Thus, a TV interphone capable of correcting distortion of an imaging lens with a simple and inexpensive configuration without obtaining complicated correction processing and obtaining an easy-to-view image could be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a diagram showing an image for explaining an operation according to the embodiment.

FIG. 3 is a diagram showing an image according to a conventional example.

[Explanation of symbols]

 Reference Signs List 1 slave unit 2 master unit 11 imaging unit 12 one-dimensional wide-angle lens 21 A / D conversion unit 22 line memory 23 distortion correction table 24 distortion correction processing unit 25 D / A conversion unit 26 monitor

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-63-196189 (JP, A) JP-A-4-61570 (JP, A) JP-A-2-127877 (JP, A) 89919 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 7/18 H04N 5/222-5/257

Claims (1)

(57) [Claims] 1. A television intercom comprising: a child unit that images a visitor or the like by an imaging unit and outputs an image signal; and a master unit that captures an image signal output from the child unit and displays the image signal on a monitor. The means includes a one-dimensional wide-angle lens that is wide-angle in the one-dimensional direction, and the parent device has a line memory that stores only the one-dimensional image signal output from the child device, and corrects one-dimensional distortion. A television interphone, comprising: a distortion correction unit that performs the correction; and a distortion correction table that stores data for the distortion correction.