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Veggie Vision by IBM

Ideas about a practical systemto make more efficient the selling

and inventory of produce in a grocery store.

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Problem is recognizing produce

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15+ years of R&D now

This information was shared by IBM researchers. Since that time, the system has been tested in small markets and has been modified according to that experience.

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Up to 400 produce types

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Practical problems of application environment

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Engineering the solution

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System to operate inside the usual checkout station

• together with bar code scanner

• together with scale

• together with accounting

• together with inventory

• together with employee

• within typical store environment

* figure shows system asking for help from the cashier in making final decision on touch screen

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Modifying the scale

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Need careful lighting engineering

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Need to segment product from background, even through plastic

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Previously published thresholding decision

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Quality segmented image obtained

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Design of pattern recognition paradigm (from 1997)

FEATURES are: color, texture, shape, and size all represented uniformly by HISTOGRAMS

Histograms capture statistical properties of regions – any number of regions.

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Matching procedure Sample product represented by

concatenated histograms: about 400 D 350 produce items x 10 samples = 3500

feature vectors of 400D each Have about 2 seconds to compare an

unknown sample to 3500 stored samples (3500 dot products)

Analyze the k nearest: if closest 2 are from one class, recognize that class (sure)

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HSI for pixel color: 6 bits for hue, 5 for saturation and intensity

For each pixel

quantify H

HIST[H]++

same for S&I

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Histograms of 2 limes versus 3 lemons

Distribution or population concept adds robustness:

• to size of objects

• to number of objects

• to small variations of color (texture, shape, size)

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Texture: histogram results of LOG filter[s] on produce pixels

Leafy produce A

Leafy produce B

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Shape: histogram of curvature of boundary of produce

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Banana versus lemon or cucumber versus lime

Large range of curvatures indicates complex object

Small range of curvatures indicates roundish object

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Size is also represented by a histogram

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Each pixel gets a “size” as the minimum distance to boundary

Purple grapes Chinese eggplants

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Learning and adaptation System “easy” to train: show it

produce samples and tell it the labels. During service: age out oldest

sample; replace last used sample with newly identified one.

When multiple labeled samples match the unknown, system asks cashier to select from the possible choices.