GB2187281A - Colour analyser - Google Patents

Colour analyser Download PDF

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Publication number
GB2187281A
GB2187281A GB08704131A GB8704131A GB2187281A GB 2187281 A GB2187281 A GB 2187281A GB 08704131 A GB08704131 A GB 08704131A GB 8704131 A GB8704131 A GB 8704131A GB 2187281 A GB2187281 A GB 2187281A
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GB
United Kingdom
Prior art keywords
meat
filter
fat
camera
picture
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08704131A
Other versions
GB2187281B (en
GB8704131D0 (en
Inventor
Jack Woollven
Anthony Jenkins
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Analytical Instruments Ltd
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Analytical Instruments Ltd
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Publication date
Application filed by Analytical Instruments Ltd filed Critical Analytical Instruments Ltd
Publication of GB8704131D0 publication Critical patent/GB8704131D0/en
Publication of GB2187281A publication Critical patent/GB2187281A/en
Application granted granted Critical
Publication of GB2187281B publication Critical patent/GB2187281B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/02—Food
    • G01N33/12—Meat; fish
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
    • G01N15/10—Investigating individual particles
    • G01N15/14—Electro-optical investigation, e.g. flow cytometers
    • G01N15/1468—Electro-optical investigation, e.g. flow cytometers with spatial resolution of the texture or inner structure of the particle
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N2021/1765—Method using an image detector and processing of image signal
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/314—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry with comparison of measurements at specific and non-specific wavelengths

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  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Food Science & Technology (AREA)
  • Physics & Mathematics (AREA)
  • Analytical Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Medicinal Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • Spectrometry And Color Measurement (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

A device for analysing the proportions of differently coloured portions in articles and in particular for analysing the proportions of lean meat and fat in meat products. Red and green filters 6,7 are placed in different parts of the field of view of a monochrome television camera disposed above a continuous black conveyor 3 carrying pieces of meat 4 to be analysed, whereby the TV picture has parts corresponding respectively to input light received via the two filters. Two equal reference frames 8,9 are defined in these two parts of the TV picture. The red filter enables all meat to be easily distinguished from the conveyor. The green filter allows darker fat to be distinguished from pink lean meat. A measuring cycle is established wherein the total area of the TV picture within the two reference frames 8,9 exceeding predetermined levels is measured alternately in each frame so as to accumulate the total area of meat and the total area of fat passing the camera. <IMAGE>

Description

SPECIFICATION Colour analyser The present invention relates to a device for analysing the proportions of differently coloured portions of an article, and in particular, but not exclusively, to a device for analysing the proportions of lean meat and fat on pieces of meat.
U.K. Patent specification 2144533 A describes an image analysis system which can be used for determining the fat content in meat. The system described in that application is capable of measuring the fat and lean content very rapidly when the lean meat is substantially lighter than the black belt upon which it is carried and the fat in the meat is substantially brighter than the palest part of the lean. Unfortunately, in certain circumstances, very dark meat is difficult to distinguish from the black belt background. Also, in other circumstances pale pink lean may appear brighter than some yellow fat in the output of a monochrome camera system. U.K. Patent specification 2144533 A to which reference is hereby directed, describes a means of using a colour TV camera to overcome some of these problems.The present application provides a simpler and more cost effective way of overcoming these problems.
In accordance with the present invention, there is provided a device for analysing the proportions of a plurality of differently coloured portions of an article, the device comprising a first filter adapted to selectively transmit light from the article over a first preselected range of wavelengths, a second filter adapted to selectively transmit light from the article over a second preselected range of wavelengths, means for detecting the intensity of light transmitted by the two said filters, respectively, and means for measuring the areas of articles which exceed pre-set levels of transmitted light through each of the said filters.
The article may be a meat product, and the first filter may be adapted to transmit light reflected from lean meat and from fat portions and the second filter may be adapted to absorb light reflected from the lean meat portions. The first filter may be red, and the second filter may be green.
There may be a third, reference filter, which may be used to calibrate the device.
Preferably, the means for detecting the light transmitted by the two filters comprises a television camera, preferably a monochromatic camera. Preferably, the light transmitted by the first and second filters is measured in turn.
If a red filter is introduced into the optical path between the camera lens and the meat under analysis, then all meat is easily differentiated from the black belt. Similarly, if a green filter is introduced into the optical path, red areas are not easily distinguished from the black background, but the yellow fat appears bright in contrast to the pink lean meat. This feature is used in the present invention to facilitate the measurement of dark meat, pale pink lean and yellow fat.
By way of example only, a specific embodiment of the present invention will now be described, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of a device according to the present invention; and Figure 2 is a view of a television screen showing the output of the camera of the device of Fig. 1.
Referring now to the drawings, Fig. 1 shows a diagrammatic representation of a camera system arranged to view a conveyor belt containing processed meat for the continuous analysis of the fat content of the meat.
A monochrome camera 1, is fitted with a lens 2, and is arranged to view a conveyor belt 3, which carries meat products 4. Between the camera lens and the conveyor belt is arranged a window 5, one half of which comprises a red filter 6, and the other half a green filter 7.
The appearance of the meat viewed on the two halves of the TV picture differs considerably. On the red half of the picture, all the meat, both lean and fat, is easily distinguished from the black background and on the green half only the white and yellow fat areas are easily distinguished from the black background.
Two reference frames, frame 8 and frame 9 of equal size, are arranged on each half of the TV picture as shown in Fig. 2 and a measuring cycle is arranged so that the total area of the TV picture exceeding certain pre-set levels is measured alternately in each frame. In this way total area of meat and the total area of fat is accumulated. The conveyor 3 is arranged to convey meat across the picture from red to green or vice-versa so that all meat measured in the red frame is also measured in the green frame. In this way fat content may be continuously monitored as the meat is conveyed below the camera.
A further reference frame may be arranged to encompass both red and green sections of the TV picture and a reference panel may be placed either alongside or above the conveyor.
The three frames, red 8, green 9, and reference 10, are shown in the TV picture of Fig.
2. The reference panel is arranged with certain areas 11 of red and white on a black background and may be used to check the stability and performance of the system.
1. A device for analysing the proportons of a plurality of differently coloured portions of an article, the device comprising a first filter adapted to selectively transmit light from the
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (10)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Colour analyser The present invention relates to a device for analysing the proportions of differently coloured portions of an article, and in particular, but not exclusively, to a device for analysing the proportions of lean meat and fat on pieces of meat. U.K. Patent specification 2144533 A describes an image analysis system which can be used for determining the fat content in meat. The system described in that application is capable of measuring the fat and lean content very rapidly when the lean meat is substantially lighter than the black belt upon which it is carried and the fat in the meat is substantially brighter than the palest part of the lean. Unfortunately, in certain circumstances, very dark meat is difficult to distinguish from the black belt background. Also, in other circumstances pale pink lean may appear brighter than some yellow fat in the output of a monochrome camera system. U.K. Patent specification 2144533 A to which reference is hereby directed, describes a means of using a colour TV camera to overcome some of these problems.The present application provides a simpler and more cost effective way of overcoming these problems. In accordance with the present invention, there is provided a device for analysing the proportions of a plurality of differently coloured portions of an article, the device comprising a first filter adapted to selectively transmit light from the article over a first preselected range of wavelengths, a second filter adapted to selectively transmit light from the article over a second preselected range of wavelengths, means for detecting the intensity of light transmitted by the two said filters, respectively, and means for measuring the areas of articles which exceed pre-set levels of transmitted light through each of the said filters. The article may be a meat product, and the first filter may be adapted to transmit light reflected from lean meat and from fat portions and the second filter may be adapted to absorb light reflected from the lean meat portions. The first filter may be red, and the second filter may be green. There may be a third, reference filter, which may be used to calibrate the device. Preferably, the means for detecting the light transmitted by the two filters comprises a television camera, preferably a monochromatic camera. Preferably, the light transmitted by the first and second filters is measured in turn. If a red filter is introduced into the optical path between the camera lens and the meat under analysis, then all meat is easily differentiated from the black belt. Similarly, if a green filter is introduced into the optical path, red areas are not easily distinguished from the black background, but the yellow fat appears bright in contrast to the pink lean meat. This feature is used in the present invention to facilitate the measurement of dark meat, pale pink lean and yellow fat. By way of example only, a specific embodiment of the present invention will now be described, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of a device according to the present invention; and Figure 2 is a view of a television screen showing the output of the camera of the device of Fig. 1. Referring now to the drawings, Fig. 1 shows a diagrammatic representation of a camera system arranged to view a conveyor belt containing processed meat for the continuous analysis of the fat content of the meat. A monochrome camera 1, is fitted with a lens 2, and is arranged to view a conveyor belt 3, which carries meat products 4. Between the camera lens and the conveyor belt is arranged a window 5, one half of which comprises a red filter 6, and the other half a green filter 7. The appearance of the meat viewed on the two halves of the TV picture differs considerably. On the red half of the picture, all the meat, both lean and fat, is easily distinguished from the black background and on the green half only the white and yellow fat areas are easily distinguished from the black background. Two reference frames, frame 8 and frame 9 of equal size, are arranged on each half of the TV picture as shown in Fig. 2 and a measuring cycle is arranged so that the total area of the TV picture exceeding certain pre-set levels is measured alternately in each frame. In this way total area of meat and the total area of fat is accumulated. The conveyor 3 is arranged to convey meat across the picture from red to green or vice-versa so that all meat measured in the red frame is also measured in the green frame. In this way fat content may be continuously monitored as the meat is conveyed below the camera. A further reference frame may be arranged to encompass both red and green sections of the TV picture and a reference panel may be placed either alongside or above the conveyor. The three frames, red 8, green 9, and reference 10, are shown in the TV picture of Fig. 2. The reference panel is arranged with certain areas 11 of red and white on a black background and may be used to check the stability and performance of the system. CLAIMS
1. A device for analysing the proportons of a plurality of differently coloured portions of an article, the device comprising a first filter adapted to selectively transmit light from the article over a first preselected range of wavelengths, a second filter adapted to selectively transmit light from the article over a second preselected range of wavelengths, means for detecting the intensity of light transmitted by the two said filters, respectively, and means for measuring the areas of articles which exceed pre-set levels of transmitted light through each of the said filters.
2. A device as claimed in claim 1 for analysing the proportions of lean meat and fat in an article of meat product, wherein the first filter is adapted to transmit light reflected from both lean meat and from fat portions of the meat article and the second filter is adapted to absorb light reflected from the lean meat portions of the meat article.
3. A device as claimed in claim 1 or 2, wherein the first filter is a red filter and the second filter is a green filter.
4. A device as claimed in claim 1, 2 or 3, wherein the means for detecting the light transmitted by the two filters comprises a television camera.
5. A device as claimed in claim 4, wherein the television camera is a monochrome camera.
6. A device as claimed in claim 4 or 5, disposed above a conveyor belt which, in use, carries pieces of meat product past the camera and wherein two reference frames are arranged within two portions of the TV picture of the camera corresponding to light received via said first and second filters, respectively, and a measuring cycle is established in which the total area of the TV picture within the frames exceeding predetermined levels is measured alternately in each frame so as to accumulate the total area of meat and the total area of fat passing the camera.
7. A device for analysing the proportions of lean meat and fat in pieces of meat product moved past the device on a continuous dark conveyor, the device comprising a monochrome television camera, a first filter disposed in a first part of the field of view of the camera and arranged to transmit light reflected from lean meat and fat portions of said meat pieces, and a second filter disposed in a second part of the field of view of the camera and arranged to transmit light reflected from the fat portions of said meat pieces, two reference frames being arranged within the TV picture of the camera within picture portions corresponding to said-first and second filters, and a measuring cycle being established wherein the total area of the TV picture within the reference frames exceeding predetermined levels is measured alternately in each frame so as to accumulate the total area of meat and the total area of fat passing the camera.
8. A device as claimed in claim 7, wherein the first filter is a red filter and the second filter is a green filter.
9. A device for analysing the proportions of a plurality of differently coloured portions of an article, the device comprising a first filter adapted to selectively transmit light from the article over a first preselected range of wavelengths and a second filter adapted to selectively absorb light from the article over a second preselected range of wavelengths, and means for detecting the light transmitted by the two said filters.
10. A device for analysing the proportions of lean meat and fat in articles of meat product, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.
GB8704131A 1986-02-26 1987-02-23 Colour analyser Expired - Fee Related GB2187281B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB868604751A GB8604751D0 (en) 1986-02-26 1986-02-26 Colour analyser

Publications (3)

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GB8704131D0 GB8704131D0 (en) 1987-04-01
GB2187281A true GB2187281A (en) 1987-09-03
GB2187281B GB2187281B (en) 1990-04-04

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GB868604751A Pending GB8604751D0 (en) 1986-02-26 1986-02-26 Colour analyser
GB8704131A Expired - Fee Related GB2187281B (en) 1986-02-26 1987-02-23 Colour analyser

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0449512A1 (en) * 1990-03-27 1991-10-02 Thurne Engineering Co Ltd Slicing machine
EP0636262A1 (en) * 1992-04-13 1995-02-01 Meat Research Corporation Image analysis for meat
WO1995021375A1 (en) * 1994-02-01 1995-08-10 Tulip International A/S System, apparatus and method for on-line determination of quality characteristics of pieces of meat, and arrangement for illumination of pieces of meat
EP0746756A1 (en) * 1994-04-27 1996-12-11 Commonwealth Scientific And Industrial Research Organisation Methods and apparatus for determining a first parameter(s) of an object
WO1999042823A1 (en) * 1998-02-20 1999-08-26 Colorado State University Research Foundation Meat color imaging system for palatability and yield prediction
WO2000049400A1 (en) * 1999-02-18 2000-08-24 Colorado State University Research Foundation Meat imaging system for palatability and yield prediction
DE19915861A1 (en) * 1999-04-08 2000-10-12 Biforce Anstalt Vaduz Process for slicing food products
WO2003004228A1 (en) * 2001-06-29 2003-01-16 Weber Maschinenbau Gmbh & Co. Kg Slicing method and device
US6997089B2 (en) 2002-06-25 2006-02-14 Formax, Inc. Optical grading system for slicer apparatus
GB2427541A (en) * 2005-06-24 2007-01-03 Aew Delford Group Ltd Vision system for food cutting and portioning apparatus
GB2428182A (en) * 2005-06-24 2007-01-24 Aew Delford Systems Vision system for food cutting and portioning apparatus
WO2007095946A1 (en) * 2006-02-22 2007-08-30 Slagteriernes Forskningsinstitut Equipment and method for detection of presence of an existence on or in the surface of an item conveyed by a conveyor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1426311A (en) * 1972-10-16 1976-02-25 Geometric Data Corp Colour separation of discrimination in pattern recognition systems
GB1465162A (en) * 1973-05-21 1977-02-23 Corning Glass Works Automated blood cell identification
GB1476793A (en) * 1973-10-23 1977-06-16 Coulter Electronics Nondestructively analysing biological cells using opto- electrical apparatus
GB1490070A (en) * 1974-01-31 1977-10-26 Metals Res Ltd Electrical circuit and apparatus and method of operating same for making measurements on differently coloured features
GB2144533A (en) * 1983-05-18 1985-03-06 Analytical Instr Ltd Image analyser

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1426311A (en) * 1972-10-16 1976-02-25 Geometric Data Corp Colour separation of discrimination in pattern recognition systems
GB1465162A (en) * 1973-05-21 1977-02-23 Corning Glass Works Automated blood cell identification
GB1476793A (en) * 1973-10-23 1977-06-16 Coulter Electronics Nondestructively analysing biological cells using opto- electrical apparatus
GB1490070A (en) * 1974-01-31 1977-10-26 Metals Res Ltd Electrical circuit and apparatus and method of operating same for making measurements on differently coloured features
GB2144533A (en) * 1983-05-18 1985-03-06 Analytical Instr Ltd Image analyser

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0449512A1 (en) * 1990-03-27 1991-10-02 Thurne Engineering Co Ltd Slicing machine
EP0636262A1 (en) * 1992-04-13 1995-02-01 Meat Research Corporation Image analysis for meat
EP0636262A4 (en) * 1992-04-13 1995-05-03 Meat Research Corp Image analysis for meat.
US5793879A (en) * 1992-04-13 1998-08-11 Meat Research Corporation Image analysis for meat
US6104827A (en) * 1992-04-13 2000-08-15 Meat & Livestock Australia Limited Image analysis for meat
WO1995021375A1 (en) * 1994-02-01 1995-08-10 Tulip International A/S System, apparatus and method for on-line determination of quality characteristics of pieces of meat, and arrangement for illumination of pieces of meat
EP0746756A1 (en) * 1994-04-27 1996-12-11 Commonwealth Scientific And Industrial Research Organisation Methods and apparatus for determining a first parameter(s) of an object
EP0746756A4 (en) * 1994-04-27 1998-11-11 Commw Scient Ind Res Org Methods and apparatus for determining a first parameter(s) of an object
US5915279A (en) * 1994-04-27 1999-06-22 Commonwealth Scientific And Industrial Research Organization Multispectral optical detection device and method
US6202493B1 (en) 1994-04-27 2001-03-20 Commonwealth Scientific And Industrial Research Organisation Methods and apparatus for determining a first parameter(s) of an object
US6198834B1 (en) 1998-02-20 2001-03-06 Keith E. Belk Meat imaging system for palatability yield prediction
WO1999042823A1 (en) * 1998-02-20 1999-08-26 Colorado State University Research Foundation Meat color imaging system for palatability and yield prediction
WO2000049400A1 (en) * 1999-02-18 2000-08-24 Colorado State University Research Foundation Meat imaging system for palatability and yield prediction
DE19915861A1 (en) * 1999-04-08 2000-10-12 Biforce Anstalt Vaduz Process for slicing food products
WO2003004228A1 (en) * 2001-06-29 2003-01-16 Weber Maschinenbau Gmbh & Co. Kg Slicing method and device
US6997089B2 (en) 2002-06-25 2006-02-14 Formax, Inc. Optical grading system for slicer apparatus
EP1534478B1 (en) 2002-06-25 2017-03-01 Formax, Inc. Optical grading system and method for slicer apparatus
EP1534478B2 (en) † 2002-06-25 2024-04-17 Formax, Inc. Optical grading method for slicer apparatus
GB2427541A (en) * 2005-06-24 2007-01-03 Aew Delford Group Ltd Vision system for food cutting and portioning apparatus
GB2428182A (en) * 2005-06-24 2007-01-24 Aew Delford Systems Vision system for food cutting and portioning apparatus
WO2007095946A1 (en) * 2006-02-22 2007-08-30 Slagteriernes Forskningsinstitut Equipment and method for detection of presence of an existence on or in the surface of an item conveyed by a conveyor

Also Published As

Publication number Publication date
GB8604751D0 (en) 1986-04-03
GB2187281B (en) 1990-04-04
GB8704131D0 (en) 1987-04-01

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Date Code Title Description
732 Registration of transactions, instruments or events in the register (sect. 32/1977)
732 Registration of transactions, instruments or events in the register (sect. 32/1977)
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19930223