JPH05298470A - Method for inputting image of two-dimensional data code - Google Patents

Abstract

PURPOSE:To normaly and surely process the deciphering of a code by permitting a binary threshold value to be normally the optimum value in accordance with ambient brightness at the time of binarizing a video signal in an image processor. CONSTITUTION:A system is constituted of a camera, a controller, an image memory and a recognizing circuit. At this case, a two-dimensional data code is image-picked-up by the camera in the controller, the signal is synchronized with the scanning line of CRT so as to be the video signal and the value between the max. and min. signals at every dot is adopted as the threshold value of the video signal at every dot on the succeeding scanning line so as to be binarized and fetched. It is preferable for the threshold value to be the approximate intermediate value of the video signals so that binarization is surely executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input method for identifying and analyzing a two-dimensional data code by an image processing device.

[0002]

2. Description of the Related Art Regarding a two-dimensional data code input device, there is Japanese Patent Application No. 4-40721 as the invention of the present inventor.

When a camera captures an image of a two-dimensional data code, the signal is imaged in synchronism with a scanning line of a CRT, and the image signal of the image of the data code is binarized. Is fixed and processed.

[0004]

In the method of processing a video signal as described above, the two-dimensional data code is picked up by a camera and the video signal of the black-and-white pattern of the code is binarized in the surrounding area. Since the pattern contrast differs depending on the brightness, if the threshold for binarizing the signal is fixed, the signal processing cannot be reliably performed due to the change in the brightness of the shooting environment. The present invention provides an image processing method that solves these problems.

[0005]

The present invention has a structure of a camera, a controller, an image memory, and a recognition circuit, in which a two-dimensional data code is picked up by the camera in the controller and the signal thereof is displayed on a CRT. The video signal is synchronized with the scanning line of, and the video signal is binarized by using the value between the maximum and the minimum of the signal of each dot of the video signal as the threshold of the video signal of each dot on the next scanning line. It is a method of inputting an image of a two-dimensional data code, which is characterized by being incorporated.

[0006]

The two-dimensional data code is picked up by the camera as shown in FIG. The pattern of this code is CR of the image processing device.
The video signal is projected on T. At that time, the maximum / minimum value (voltage) value is captured for each dot of the video signal on one scanning line of the CRT, and the value between the maximum and minimum values is used as the threshold value of the video signal for each dot of the next scanning line. The video signal is binarized.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS It is preferable that this threshold value is set to an approximately intermediate value of the video signal, so that it can be binarized more reliably.

[0008]

As described above, according to the present invention, when a two-dimensional data code is binarized by an image processing device by using an image processing device, the binarization threshold is constantly set to the highest value depending on the ambient brightness. Has the right value. Therefore, even if the ambient brightness changes, the code can always be read reliably.

[Brief description of drawings]

FIG. 1 is a block diagram of an apparatus for implementing an image input method of the present invention.

Claims (1)

[Claims] 1. A camera, a controller, an image memory, and a recognition circuit, wherein the controller captures an image of a two-dimensional data code and the signal is imaged in synchronization with a scanning line of a CRT. A two-dimensional image data which is binarized and taken in by using a value between the maximum and minimum values of the signal for each dot of the image signal as a threshold value of the image signal for each dot on the next scanning line. Data code image input method.