Image Processing for the Food Industry

The following sections are included:

• Contents

• Preface

• About the Author

• Acknowledgements

• Glossary of Abbreviations

The following sections are included:

• Food and its production
  • Quality control and other issues

• Image processing and machine vision

• Biological versus machine vision

• How can image processing help with food processing?

• The following chapters

The following sections are included:

• Introduction

• Images

• Image processing
  • Pixel operations
  • Window operations
  • Some problems and implementation issues
    • Eliminating underflow and overflow
    • Solving image border problems
    • Sequential and parallel processing
    • The need for restoring operations
    • Speed of processing
    • Processing in the spatial frequency domain

• Median and rank-order filters

• Thresholding

• Adaptive thresholding

• Edge detection

• Concluding remarks

The following sections are included:

• Introduction

• Connected components analysis of images

• Skeletons and thinning

• Skeleton-based analysis of shape

• Distance functions

• General dilation and erosion operators

• Properties of dilation and erosion operators

• Closing and opening

• Summary of morphological operations

• Boundary pattern analysis
  • The centroidal profile approach

• Concluding remarks

The following sections are included:

• Introduction

• From template matching to inference

• Finding features

• Line location

• Circle location

• Ellipse location

• Graph matching

• Using the Hough transform for point pattern matching

• Concluding remarks

The following sections are included:

• Introduction

• Tackling the problem of texture analysis

• Laws' approach

• Ade's approach

• Concluding remarks

The following sections are included:

• Introduction

• Stereo vision

• Shape from shading

• Views and projections

• Motion

• Concluding remarks

The following sections are included:

• Introduction

• Bayes' approach to SPR

• The nearest neighbour approach

• Artificial neural networks

• Supervised and unsupervised learning

• Principal components analysis

• Concluding remarks

The following sections are included:

• Introduction

• Phases in the inspection process

• Details of the inspection process

• Lighting schemes
  • Principles for producing regions of uniform illumination
  • Case of two infinite parallel strip lights
  • Case of circular and square ring lights
  • Summary

• Concluding remarks

The following sections are included:

• Introduction

• A basic case study: Jaffacake inspection
  • The problem
  • The solution
  • Image acquisition
  • Product location
  • Hardware for real-time operation
  • Discussion

• Case study: inspection of cream biscuits

• Short case studies of baked product inspection
  • Description of the textural appearance of bread crumb (Bertrand et al. 1992)
  • Development of an objective crumb-grain measurement (Rogers et al. 1995)
  • Automated inspection of bread and loaves (Batchelor 1993)
  • Fast boundary extraction of biscuits (Wu and Rodd 1991)
  • Fast location of biscuits by line sampling (Davies 1987)
  • Location of cherries on cup cakes (Chan and Batchelor 1993)

• Concluding remarks

The following sections are included:

• Introduction

• Case study: location of dark contaminants in cereals
  • Application of morphological and non-linear filters to locate rodent droppings
  • Appraisal of the various schemas
  • Summary

• Case study: location of insects
  • The vectorial strategy for linear feature detection
  • Designing linear feature detection masks for larger windows
  • Application to cereal inspection
  • Summary and discussion

• Case study: high speed grain location
  • Extending an earlier sampling approach
  • Application to grain inspection
  • Summary

• Short case studies of grain and nut inspection
  • Kernel positioning for grain measurement (Casady and Paulsen 1989)
  • A dedicated wheat grain image analyser (Keefe 1992)
  • Discrimination between wheat grain varieties and classes (Zayas and Steele 1990)
  • Classification of wheat kernels (Thomson and Pomeranz 1991)
  • Detection of maize and soybean quality factors (Paulsen et al. 1989)
  • Detection of surface defects of maize kernels (Liao et al. 1994)
  • Detection of early split pistachio nuts (Pearson and Slaughter 1996)
  • Detection of stained pistachio nuts (Pearson 1996)
  • Automatic grading of peanuts (Dowell 1992)
  • X-ray detection of weevils in wheat (Keagy and Schatzki 1993)
  • X-ray detection of insects in pistachio nuts (Casasent et al. 1997)
  • Detection of insects inside wheat kernels by NIR imaging (Ridgway and Chambers 1998)
  • On-line measurement of bran in flour (Whitworth et al. 1997)

• Concluding remarks

The following sections are included:

• Introduction

• X-ray image acquisition

• Case study: reliable thresholding of X-ray images
  • Variance-based thresholding measures
  • Entropy-based thresholding measures
  • A modified entropy measure

• Case study: inspection of frozen food packs
  • General strategy of the system
  • Further details of the system

• Case study: design of hardware for inspection of frozen food packs
  • Real-time processing issues
  • Main contenders for real-time inspection hardware
  • The Centurion software-based real-time system
    • Communication channels
    • System components
    • Performance
    • Use of the Centurion for foreign object detection
  • Summary

• Short case studies of X-ray inspection
  • Combining X-ray imaging and machine vision (Wagner 1987)
  • Intelligent visual inspection of food products (Chan et al. 1990)
  • Approaches to foreign body detection in foods (Graves et al. 1998)
  • Defect detection in apples (Schatzki et al. 1997)
  • Detection of interior voids, inclusions and pests (Tollner et al. 1993)
  • Inspection of metal and glass containers (Novini 1990)
  • Inspection of packaged foods (Cambier and Pasiak 1986)
  • Inspection of canned products (Penman et al. 1992)
  • 3D inspection of food products (Graves et al. 1994)

• Concluding remarks

The following sections are included:

• Introduction

• Case study: guidance of a crop-spraying vehicle
  • 3D aspects of the task
  • Real-time implementation

• Case study: model-based tracking of animals

• Case study: inspection and grading of potatoes
  • Colour inspection of potatoes

• Case study: inspection of apples
  • Shape
  • Colour
  • Russetting
  • Blemish detection
    • Problems with snakes

• Case study: inspection and grading of mushrooms

• Concluding remarks

The following sections are included:

• Introduction

• Case study: species sorting of fish

• Case study: grading of prawns

• The problem of meat processing

• Case study: inspection and grading of poultry parts
  • Tasks associated with packaging

• Concluding remarks

The following sections are included:

• Introduction

• Design of inspection systems—the status quo

• System optimization

• The value of case studies

• The way to go

• Further considerations relating to hardware accelerators

• The need for rigorous timing analysis of vision algorithms

• Concluding remarks

The following sections are included:

• Introduction

• The range of the case studies

• The cost of vision hardware

• The potential range of applications of vision

• Prognosis

The following sections are included:

• References

• Author Index

• Subject Index