JP2880813B2 - Nori defect inspection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laver defect inspection apparatus.

[0002]

2. Description of the Related Art A conventional seaweed defect inspection apparatus uses a semi-fixed image when a digital image signal of a seaweed to be inspected outputted from an image capturing unit is converted into a binary image signal by an image binarization judging unit. The conversion is performed using a slice level (for example, a dynamic parameter that changes the level in steps or a software parameter).

[0003]

In the above-mentioned conventional laver defect inspection apparatus, the digital binarization judging section converts the digital image signal of the laver to be inspected into a binarized image signal by using a semi-fixed image slice level. Since the conversion is performed, there is a disadvantage that the amount of light applied to the laver itself varies due to, for example, the thickness of the individual laver, and erroneous detection of an opaque foreign substance occurs.

[0004]

A laver defect inspection apparatus according to the present invention converts an analog image signal from a one-dimensional camera for photographing laver into a digital image signal at an image capturing section and passes the laver through a transport section. A laver defect inspection device that inspects for contamination of the opaque foreign matter by detecting and analyzing a change in a digital image signal output from the image capturing unit to detect a laver passage front end; and the front end detection An average level calculator for calculating an image average level of a predetermined designated number of scanning lines of the digital image signal according to a signal capture command output from the unit; and an image based on the image average level output from the average level calculator. A slice level setting unit for setting a slice level; and an image slice level output from the slice level setting unit. A binary image determining unit for converting an image signal into a binary image signal, and a defect inspection determination for determining whether or not the opaque foreign matter of the laver is mixed based on the binary image signal output from the binary image determining unit. Part.

[0005]

Next, the present invention will be described with reference to the drawings.

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

In FIG. 1, a light source 9 for irradiating the seaweed 10 conveyed by a conveying unit 8 with light from below the conveying unit 8 and a one-dimensional transmitted light image of the seaweed 10 irradiated with the light are shown in FIG. A one-dimensional camera 1 to be captured, an image capturing unit 2 that converts an analog image signal a from the one-dimensional camera 1 into a digital image signal b, and a change in the digital image signal b output from the image capturing unit 2 is detected and analyzed. And a signal detecting command d output from the tip detecting unit 3 to detect a passing tip of the laver 10, and an image average level e of a predetermined designated number of scanning lines of the digital image signal b. , A slice level setting unit 5 for setting an image slice level f from the image average level e output from the average level calculation unit 4, and an output from the slice level setting unit 5. An image binarization determining unit 6 that converts a digital image signal b into a binary image signal c based on the obtained image slice level f, and a laver 10 based on the binary image signal c output from the image binary determination unit 6. And a defect inspection determination unit 7 for determining whether or not there is any opaque foreign matter.

Next, the operation of this embodiment for determining the presence / absence of an opaque foreign matter mixed in laver will be described.

Light is applied to a laver 10 passing through the transport section 8 at a constant speed by a light source 9 disposed below a gap between the transport sections 8, and the one-dimensional camera 1 transmits one-dimensional transmitted light of the laver 10. Capture images. An analog image signal a corresponding to the one-dimensional transmitted light image of the laver 10 is output from the one-dimensional camera 1 and converted into a digital image signal b in the image embedding unit 2.
The leading edge detector 3 captures the digital image signal b and detects and analyzes a change in the signal, thereby detecting the leading edge of the laver 10 and outputting a signal capturing command d to the average level calculator 4. The average level calculating section 4 receives the signal fetching instruction d and performs a predetermined number of times, for example, 2 to 3 for a predetermined number of times.
The sum of the digital image signals b in the entire effective visual field for the scanning lines is calculated and divided by the number of pixels in the effective visual field, thereby outputting an image average level e per pixel.

The slice level setting unit 5 receives the image average level e and generates a digital image signal b of the laver 10 which is currently passing through into a binarized image signal c which makes it easy to determine the presence or absence of opaque foreign matter. Is set by a conversion table created based on empirical data, for example.

The image binarization judging section 6 converts the digital image signal b into a white or black binarized image signal c based on the value of the image slice level f. The defect inspection determination unit 7 processes the binarized image signal c to detect that the average digital image signal b of the laver 10 itself contains a signal of a transparent foreign substance having an extremely low level. Then, the defect of the laver 10 is determined.

[0012]

As described above, the present invention has an arrangement in which the image average level of the image of the tip of each laver passing through the transport section is calculated and the slice level is set, whereby the average of the laver itself is obtained. Binarized images can be generated without being influenced by typical digital image signal variations,
This has the effect that opaque foreign substances mixed into the laver can be detected stably.

[Brief description of the drawings]

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

[Explanation of symbols]

 Reference Signs List 1 1D camera 2 Image capture unit 3 Tip detection unit 4 Average level calculation unit 5 Slice level determination unit 6 Image binarization determination unit 7 Defect inspection determination unit 8 Transport unit 9 Light source 10 Nori a Analog image signal b Digital image Signal c Binary image signal d Signal capture command e Image average level f Image slice level

Continuation of the front page (56) References JP-A-62-212553 (JP, A) JP-A-2-40542 (JP, A) JP-A-63-84464 (JP, A) JP-A-2-253142 (JP) , A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01B 11/00-11/30 G01N 21/00-21/89

Claims (1)

(57) [Claims] 1. A laver defect inspection apparatus for converting an analog image signal from a one-dimensional camera for imaging laver into a digital image signal at an image capturing unit and inspecting the laver for opaque foreign matter passing through a transport unit. A tip detecting unit that detects a passing tip of the laver by detecting and analyzing a change in a digital image signal output from the image capturing unit; and a digital image signal according to a signal capturing command output from the tip detecting unit. An average level calculation unit that calculates an image average level of a predetermined number of scanning lines,
A slice level setting unit for setting an image slice level from the image average level output from the average level calculation unit, and converting the digital image signal into a binary image signal based on the image slice level output from the slice level setting unit A seaweed defect, comprising: a binarization determining unit that performs image processing; and a defect inspection determination unit that determines presence / absence of opaque foreign matter in the laver based on the binarized image signal output from the binarization determining unit. Inspection equipment.