JPH0284966U

JPH0284966U -

Info

Publication number: JPH0284966U
Application number: JP16343088U
Authority: JP
Priority date: 1988-12-19
Filing date: 1988-12-19
Publication date: 1990-07-03
Anticipated expiration: 2003-12-19
Also published as: JPH0738999Y2

Description

[Brief explanation of the drawing]

第１図はこの考案の一実施例に係るデータ読取
装置の全体構成図、第２図は記録媒体に記録され
る符号化画像の例を示す図、第３図はスレツシユ
ホールド決定回路の構成図、第４図は第１図のデ
ータ読取装置の各部の信号のタイミングチヤート
、第５図は２値化結果からスレツシユホールドレ
ベルを変更する処理のフローチヤートである。１……イメージセンサー、４……２値化回路、
５……スレツシユホールドレベル決定回路、５１
……平均回路、５２……ＣＰＵ、５３……変更回
路、２１……バー（既知のパターン）。 FIG. 1 is an overall configuration diagram of a data reading device according to an embodiment of this invention, FIG. 2 is a diagram showing an example of an encoded image recorded on a recording medium, and FIG. 3 is a configuration of a threshold determination circuit. 4 is a timing chart of signals in each part of the data reading device shown in FIG. 1, and FIG. 5 is a flowchart of processing for changing the threshold level from the binarization result. 1... Image sensor, 4... Binarization circuit,
5...Threshold level determination circuit, 51
... average circuit, 52 ... CPU, 53 ... change circuit, 21 ... bar (known pattern).

Claims

[Claims for Utility Model Registration] (1) A data reading device that reads data from a recording medium on which an image encoded with data is recorded, which converts the image on the recording medium into an analog electrical signal and outputs it line by line. image sensor means; averaging means for obtaining an average value of the level of an analog electrical signal of one line of image from the image sensor means; and averaging means for averaging the analog electrical signal of the image of the next line provided from the image sensor means. A data reading device comprising: binarization means for binarizing according to the average value obtained by the means. (2) In a data reading device that reads data from a recording medium on which an image encoded with data is recorded, an image sensor means that converts the image of the recording medium into an analog electrical signal and outputs it; Threshold level generation means for generating a threshold level when converting into a value; and binarization means for binarizing the analog electrical signal according to the threshold level; The image includes a known pattern, and the threshold level generating means is
The data is characterized by comprising a threshold level determining means for variably determining a threshold level so that the data binarized by the binarizing means includes data corresponding to a known pattern. reading device. (3) In a data reading device that reads data from a recording medium on which an image encoded with data is recorded, image sensor means converts the image of the recording medium into an analog signal and outputs it line by line along the main scanning direction. Then, obtain the average value of the analog electrical signal of the first line of image from the image sensor means and calculate 2.
averaging means for obtaining an initial value of a threshold level for value conversion; and binarization means for binarizing the analog electrical signal of each line of image from the image sensor means according to the threshold level. and, in the image of the recording medium, bright and dark bars with a known width ratio are recorded along the sub-scanning direction of the image sensor means, and furthermore, a binary bar of the binarization means is recorded. Measure the ratio of the widths of the above-mentioned bright and dark bars from the converted image data for one line, correct the current value of the threshold level according to the measurement result, and adjust the corrected threshold level. 1. A data reading device comprising threshold level correction means for setting a threshold level for binarizing an analog electrical signal of an image of the next line.