Banknote recognition method based on sorter dust accumulation and sorter

Patent metadata

Field	Value
Publication number	US-9928677-B2
Application number	US-201515328814-A
Country	US
Kind code	B2
Filing date	Aug 24, 2015
Priority date	Sep 11, 2014
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

A banknote recognition method based on sorter dust accumulation and a sorter. An effective region boundary is determined by using a gray-scale difference between a foreground and a background of a sensor image signal, an edge is searched for by comprehensive means of signal features of various sensors, detection direction change and secondary scanning, and finally the effective boundary of the image region is relocated, so that the detection rate and recognizing accuracy of the sorter can be greatly improved. The sorter comprises a banknote inlet, a banknote outlet, a banknote exit port, a conveying rail and a recognizing module. The recognizing module comprises two sets of CIS image sensors arranged oppositely, two sets of light transmitting plates arranged oppositely, a storage module, a detection module and a display module.

First claim

The invention claimed is:

1. A banknote recognition method based on sorter dust accumulation, comprising:
S1, collecting, by a collecting module, a reflection spectrum image and a transmission spectrum image of a banknote;
S2, positioning, by a positioning and determining module, four edges of the reflection spectrum image and determining whether the four edges of the reflection spectrum image are positioned successfully, obtaining a positioned image and performing steps S3 and S4 if the four edges of the reflection spectrum image are positioned successfully, and performing step S5 if the four edges of the reflection spectrum image are not positioned successfully;
S3, performing, by a first rotation mapping module, angular rotation mapping on the positioned image, to obtain a positive image of the reflection spectrum image;
S4, determining, by a second determining module, whether the positive image of the reflection spectrum image is normal, performing step S7 if the positive image of the reflection spectrum image is normal, and performing step S5 if the positive image of the reflection spectrum image is not normal;
S5, positioning, by a positioning module, four edges of the transmission spectrum image, performing steps S6 and S7 if the four edges of the transmission spectrum image are positioned successfully, and performing step S8 if the four edges of the transmission spectrum image are not positioned successfully;
S6, mapping, by a second rotation mapping module, the four edges of the transmission spectrum image to the reflection spectrum image and performing angular rotation mapping, to obtain the positive image of the reflection spectrum image;
S7, recognizing, by a recognizing module, the banknote; and
S8, returning, by a returning module, the banknote.

2. The banknote recognition method based on sorter dust accumulation according to claim 1 , wherein step S4 comprises:
accumulating sum(j) (0<j<1/5W) each time when a pixel point of the positive image of the reflection spectrum image meets the following criterion:
notegray(i,W−j)−notegray(i, j)>Threshold(0<i<H,0<j<1/5W), or
notegray(i, j)−notegray(i,W−j)>Threshold(0<i<H,0<j<1/5W);
determining that the positive image is a dust image and accumulating a statistical variable SUM if sum(j)>T; and
determining that the positive image is an abnormal edge detection image and performing step S5 if SUM>T 1 , otherwise performing step S7,
wherein notegray(i, j) denotes a gray value of the pixel point in the i-th row and the j-th column of the reflection spectrum image, H denotes a height of the reflection spectrum image, W denotes a width of the reflection spectrum image, Threshold denotes a set threshold, T denotes a threshold of a number of dust accumulation points in a single column, and T 1 denotes a threshold of a number of dust accumulation columns.

3. The banknote recognition method based on sorter dust accumulation according to claim 1 , wherein step S7 comprises
performing denomination recognition, orientation recognition, authentication, and recognition for sorting function on the banknote.

4. The banknote recognition method based on sorter dust accumulation according to claim 1 , wherein step S2 comprises:
S21, positioning the four edges of the reflection spectrum image; and
S22, determining whether the four edges of the reflection spectrum image are positioned successfully, obtaining the positioned image and performing steps S3 and S4 if the four edges of the reflection spectrum image are positioned successfully, and performing step S5 if the four edges of the reflection spectrum image are not positioned successfully.

5. The banknote recognition method based on sorter dust accumulation according to claim 4 , wherein the four edges comprises a left edge, a right edge, an upper edge and a lower edge, and step S21 comprises:
searching from a left side of the reflection spectrum image, suspending the searching if the following criterion is met for a pixel point:

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marking coordinates of the pixel point, obtaining marked coordinates of a series of such pixel points and performing straight-line fitting on the pixel points to complete positioning the left edge; and
positioning the right edge, the upper edge and the lower edge in a same manner as positioning the l

Assignees

• Grg Banking Equipment Co Ltd

Inventors

• Wang Yang
• Liang Tiancai

Classifications

• G07D7/122 Primary

  Physics · mapped topic

• G07F7/04

  by paper currency · CPC title

• G07D7/2008

  using pre-processing, e.g. de-blurring, averaging, normalisation or rotation · CPC title

• G07D11/0084

  Physics · mapped topic

• G07D11/0018

  Physics · mapped topic