CN201927055U - Barcode layer boundary direction determining device based on Hough transform - Google Patents

Abstract

The utility model discloses a barcode layer boundary direction determining device based on Hough transform, which comprises a scanning area and coordinate origin determining unit, a discretization unit, a Hough transform unit, a statistical unit, a primary selection unit, a weighting summation unit and a parameter selection unit, wherein the discretization unit is connected with the scanning area and coordinate origin determining unit and the Hough transform unit, the statistical unit is connected with the Hough transform unit and the primary selection unit, and the weighting summation unit is connected with the primary selection unit and the parameter selection unit. By the aid of the device, the directions of a plurality of barcode layer boundaries are determined by the aid of the Hough transform preformed on bounding points of the barcode layer boundaries so that accuracy of determining the directions of the barcode layer boundaries is improved.

Description

A kind of bar code layers separatrix direction based on the Hough conversion is determined device

[technical field]

The utility model relates to a kind of bar code layers separatrix direction and determines device, and particularly a kind of bar code layers separatrix direction based on the Hough conversion is determined device.

[background technology]

Barcode technology is an appearance coding, printing, identification, the data acquisition and processing (DAP) emerging technology that grows up on computer technology and infotech basis.Barcode technology is because its identification is quick, accurate, reliable and low cost and other advantages, be widely used in fields such as commerce, taking care of books, storage, post and telecommunications, traffic and Industry Control, and certainly will in " Internet of Things " that rise gradually used, bring into play great function.

The bar code that is widely used at present comprises bar code and two-dimensional bar code.Bar code claims linear bar code to be made up of a plurality of " bars " that are arranged in parallel and " sky " unit again, and bar code information is expressed by bar and empty different in width and position.Bar code is not then expressed any information just in a direction (generally being horizontal direction) expressing information in vertical direction, so information capacity and space availability ratio are lower, and promptly can't discern after bar code is damaged.

Two-dimensional bar code is made up of the chequered with black and white particular geometric figure that distributes on two-dimensional directional according to certain rules, its can be on two-dimensional directional expressing information, so information capacity and space availability ratio are lower, and have certain verifying function.Two-dimensional bar code can be divided into stack two-dimensional bar code and matrix two-dimensional barcode.The stack two-dimensional bar code is that the bar code by the multirow cutting back piles up and forms, and representational stack two-dimensional bar code comprises PDF417, Code 49, Code 16K etc.Matrix two-dimensional barcode is made up of black, the white module that is distributed in by pre-defined rule in the matrix, and representational matrix two-dimensional barcode comprises Codeone, Aztec, Date MatriX, QR sign indicating number etc.

Often there is certain angle of inclination in bar code image, and needs to determine above-mentioned angle of inclination and it is proofreaied and correct by the marginal direction of bar code layers in decode procedure.Yet the marginal direction of bar code layers is generally only decided by a bar code layers separatrix in the prior art, has certain error.Therefore, need a kind of device that can accurately determine the bar code image angle of inclination.

[utility model content]

In order to solve the problems of the technologies described above, the utility model provides a kind of bar code layers separatrix direction based on the Hough conversion to determine device, can determine the marginal direction of bar code layers exactly thus.

The utility model solves the problems of the technologies described above the technical scheme that is adopted and provides a kind of bar code layers separatrix direction based on the Hough conversion and determine device, and this bar code layers separatrix direction determines that device comprises: scanning area and true origin determining unit; The discretize unit is connected with the true origin determining unit with scanning area; The Hough converter unit is connected with the discretize unit; Statistic unit is connected with the Hough converter unit; The primary election unit is connected with statistic unit; Weighted sum unit is connected with the primary election unit; Parameter selection unit is connected with weighted sum unit.

By said apparatus, by being carried out the Hough conversion, the separation on a plurality of bar code layers separatrix determines the marginal direction of bar code layers, can improve the accuracy that bar code layers separatrix direction is determined.

[description of drawings]

Fig. 1 is a schematic block diagram of determining device according to bar code layers of the present utility model separatrix direction;

Fig. 2 is the synoptic diagram according to scanning area of the present utility model and true origin deterministic process;

Fig. 3 is the synoptic diagram according to two-dimentional totalizer matrix of the present utility model.

[embodiment]

The utility model provides a kind of bar code layers separatrix direction based on the Hough conversion to determine device, and this device improves the accuracy that bar code layers separatrix direction is determined by the separation on a plurality of bar code layers separatrix being carried out the Hough conversion.

As shown in Figure 1, bar code layers of the present utility model separatrix direction determines that device comprises scanning area and true origin determining unit, discretize unit, Hough converter unit, statistic unit, primary election unit, weighted sum unit and parameter selection unit.Scanning area and true origin determining unit are used for determining scanning area and true origin on bar code image.

Specifically, as shown in Figure 2, scanning area and true origin determining unit utilize the multi-strip scanning line to search for bar code border in bar code image.For example, with the PDF417 bar code is example, scanning area and true origin determining unit scan bar code image along each sweep trace, after scanning a black and white frontier point, with this black and white frontier point is that benchmark continues to scan 8 black and white frontier points forward, and the spacing (for example, number of modules) between definite each black and white frontier point, and utilize corresponding border judgment rule to judge whether the spacing between each black and white frontier point meets corresponding border rule.In the present embodiment, before scanning area and true origin determining unit are not determined the bar code border type, preferably utilize the judgement that walks abreast of spacing between each the black and white frontier point on 81111113 border judgment rules, 31111118 border judgment rules, 71111113 border judgment rules and sweep trace of 31111117 border judgment rules, improve judgement speed thus.After scanning area and true origin determining unit are determined bar code border, can determine with reference to col width W according to the spacing of the both sides black and white frontier point on each sweep trace.

Subsequently, scanning area and true origin determining unit utilize the black and white frontier point of the close bar code inside on the multi-strip scanning line to determine bar code row border ab.In a preferred embodiment, can utilize traditional Hough changing method to calculate the best straight line equation of a plurality of black and white frontier points of process, determine bar code row border ab thus.

Behind definite bar code row border ab, scanning area and true origin determining unit chosen distance on bar code row border ab is first A and second B of H, and at first A of chosen distance and second thirdly C and the 4th D that B is W (with reference to col width) respectively through first A and second B and on perpendicular to the vertical line of bar code row border ab.Subsequently, with first A, second B, thirdly C and the 4th D are that the summit determines that a wide W of being and height are the rectangular area of L, and with this rectangular area as scanning area.

After having determined scanning area, scanning area and true origin determining unit are at the arranged outside true origin O of scanning area.Specifically, in a preferred embodiment, can be at the arranged outside true origin O of first A with C thirdly or second B and the 4th the defined zone boundary of D, true origin O distance areas border is L, and in a preferred embodiment, L is smaller or equal to 50 pixels.

After scanning area and true origin determining unit are determined scanning area and true origin O, the discretize unit determines that according to scanning area and true origin O bar code layers marginal position angle span and initial point are apart from span, and in the span of position angle, select a plurality of angle discrete values, select in apart from span a plurality of at initial point apart from discrete value.Specifically, the discretize unit with initial point apart from span be taken as (H, H+L).In addition, the azimuth angle theta of the vertical direction relative coordinate initial point O of bar code row border ab is further determined in the discretize unit ', and the position angle span is taken as (θ '-Δ θ 1, θ '+Δ θ 1).In a preferred embodiment, Δ θ is 1＜30 °.The discretize unit preferably obtains the angle discrete value by increasing progressively successively with fixed angle step-length (for example, 1 radian), and the discretize unit is preferably by increasing progressively successively with fixed range step-length (for example, 1 pixel) to come apart from discrete value.

Subsequently, the Hough converter unit obtains the rectangular coordinate of a plurality of layers of separation at least two interior bar code layers separatrix of scanning area, and respectively with rectangular coordinate and each angle discrete value substitution formula ρ=xcos θ+ysin θ of a plurality of layers of separation, to determine that at each layer separation each angle discrete value is pairing apart from discrete value, wherein x, y are rectangular coordinate, θ is the angle discrete value, and ρ is that each angle discrete value is pairing apart from discrete value.

Then, statistic unit utilization two dimension totalizer matrix is to the angle discrete value and pairingly add up apart from discrete value.Specifically, statistic unit produces a two-dimentional totalizer matrix A, and with each matrix element A[i, j] put 0.Statistic unit according to each the angle discrete value that draws by aforementioned calculation and respective distances discrete value to the corresponding matrix element A[i in the two-dimentional totalizer matrix A, j] add up.Just, statistic unit according to each angle discrete value and calculate apart from the matrix element A[i of discrete value with correspondence, j] add 1, make each matrix element A[i in the two-dimentional totalizer matrix, j] accumulated value represent the angle discrete value and apart from the occurrence number of the correspondence combination of discrete value.After whole frontier points are carried out aforesaid operations, accumulated value matrix that can be as shown in Figure 3.

Subsequently, each matrix element apart from accumulated value maximum in the pairing a plurality of matrix elements of discrete value is confirmed in the primary election unit, and the matrix element of selecting predetermined quantity from the matrix element of accumulated value maximum is as the primary election matrix element.For example, in the present embodiment, as shown in Figure 3, the primary election unit is confirmed the matrix element apart from selection accumulated value maximum in discrete value ρ 0 to the ρ 6 pairing matrix element row at first respectively, and therefrom selects the matrix element A[2 of 6 accumulated value maximums, 5]=17, A[4,6]=17, A[3,4]=16, A[0,1]=16, A[4,3]=14, A[6,2]=14, as the primary election matrix element.

After the primary election matrix element is determined in the primary election unit, weighted sum unit is weighted summation with the accumulated value of each primary election matrix element and the accumulated value of other primary election matrix elements, and wherein the weighted value of weighted sum is by the difference decision of each primary election matrix element and the pairing angle discrete value of other matrix elements.Specifically, the absolute value of the angle discrete value difference of each primary election matrix element and other matrix elements is big more, and the weighted value of weighted sum is more little.

In the present embodiment, weighted sum unit is determined the weighted sum value of each primary election matrix element in the following way:

s[2，5]＝17×100/(|2-2|+1)+17×100/(|2-4|+1)+16×100/(|2-3|+1)+16×100/(|2-0|+1)+14×100/(|2-4|+1)+14×100/(|2-6|+1)＝4345

s[4，6]＝17×100/(|4-4|+1)+17×100/(|4-2|+1)+16×100/(|4-3|+1)+16×100/(|4-0|+1)+14×100/(|4-4|+1)+14×100/(|4-6|+1)＝5252

s[3，4]＝16×100/(|3-3|+1)+1/×100/(|3-2|+1)+1/×100/(|3-4|+1)+16×100/(|3-0|+1)+14×100/(|3-4|+1)+14×100/(|3-6|+1)＝4750

s[0，1]＝16×100/(|0-0|+1)+17×100/(|0-2|+1)+17×100/(|0-4|+1)+16×100/(|0-3|+1)+14×100/(|0-4|+1)+14×100/(|0-6|+1)＝3386

S[4，3]＝14×100/(|4-4|+1)+17×100/(|4-2|+1)+17×100/(|4-4|+1)+16×100/(|4-3|+1)+16×100/(|4-0|+1)+14×100/(|4-6|+1)＝5252

s[6，2]＝14×100/(|6-6|+1)+17×100/(|6-2|+1)+17×100/(|6-4|+1)+16×100/(|6-3|+1)+16×100/(|6-4|+1)+14×100/(|6-4|+1)＝3400

In the present embodiment, calculate for convenience, angle discrete value difference is directly replaced by the following target difference corresponding to the angle discrete value of this matrix element, and multiply by M as weighted value (in the present embodiment with the inverse that the absolute value of subscript difference adds N, N=1, M=100).Yet those skilled in the art can design the weighted value of other weighted sum fully, as long as this weighted value is along with the increase of the absolute value of the angle discrete value difference of each primary election matrix element and other matrix elements and diminish.

After weighted sum unit was carried out above-mentioned weighted sum to the accumulated value of above-mentioned primary election matrix element, parameter selection unit selected the pairing angle discrete value of primary election matrix element of weighted sum value maximum as the marginal direction parameter of bar code layers.For example, in the present embodiment, it is 5252 primary election matrix element A[4 that parameter selection unit is selected the weighted sum value, 6] and A[4,3] pairing angle discrete value θ 4 is as the marginal direction parameter of the bar code layers in the utility model.

By said apparatus, by being carried out the Hough conversion, the separation on a plurality of bar code layers separatrix determines the marginal direction of bar code layers, can improve the accuracy that bar code layers separatrix direction is determined.

In the above-described embodiments, only the utility model has been carried out exemplary description, but those skilled in the art can carry out various modifications to the utility model after reading present patent application under the situation that does not break away from spirit and scope of the present utility model.

Claims (1)

1. the bar code layers separatrix direction based on the Hough conversion is determined device, it is characterized in that, described bar code layers separatrix direction determines that device comprises:

Scanning area and true origin determining unit;

The discretize unit is connected with the true origin determining unit with described scanning area;

The Hough converter unit is connected with described discretize unit;

Statistic unit is connected with described Hough converter unit;

The primary election unit is connected with described statistic unit;

Weighted sum unit is connected with described primary election unit;

Parameter selection unit is connected with described weighted sum unit.

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