Post on 25-Feb-2016
description
Business Identification:Spatial Detection
Alexander DarinoWeek 7
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Weaknesses to Current Approach
LatitudeLongitude
Geocoding
ReverseGeocoding
Nearby Businesses
Image OCR Detected Text
Business Name
Matching
BusinessIdentification
Business Spatial
Detection
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Alternative: Image Matching
Alternative: Image Matching
• Weaknesses:– Low Availability of Storefront Images (< 50% Avg)• George Aiken area businesses with photos: 18/35• Brueggers area businesses with photos: 22/40• Tambellini area businesses with photos: 8/22
– Available Images too small (100 x 100)• Not a viable solution
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Alternative: Template Matching
• Tambellini• Tambellini• Tambellini• Tambellini• Tambellini• Tambellini• Tambellini• Tambellini
Alternative: Template Matching
• Progress– Able to generate templates– Able to extract SIFT features using Lowe’s
implementation– Able to match SIFT features using Lowe’s
implementation• Problems– Features are being matched to garbage
Alternative: Template Matching
Alternative: Template Matching
Alternative: Template Matching
Alternative: Template Matching
Alternative: Template Matching
• Currently on-hold– Need to discuss solution with Amir– Currently looking into another alternative…
Alternative: Scene Text Recognition• State of the Art:– STR ≠ OCR– Far superior to our ‘naïve’ approaches to STR (ie. OCR, Image
matching, SIFT)• OCR only works for highly controlled environments.
CEDAR, ICDAR, etc not helpful• STR works for unconditioned environments– Scale invariant– Color/intensity invariant– Font invariant– Lexicon-Assisted
Alternative: Scene Text Recognition
• No STR implementations readily available• University of Massachusetts specializes in STR– Papers describe enhancements and unification of
previous work, but not algorithms– Will email for blackbox implementation
• Currently looking into ‘previous work’– More models– Some algorithms
Alternative: Scene Text Recognition
• Options– Email authors for implementation– Try to implement STR as per described models• Blackboxes whenever possible (email!)• Code when blackboxes are not available
– Try to implement crude STR via blackboxes
Text Detection Orthorectification Increase Contrast OCR Detected
Text
STR Implementation
• STR Implementation: “Automatic Detection and Recognition of Signs From Natural Scenes”
Multiresolution-based potential
characters detection
Character/layout geometry and color properties analysis
Local affine rectification
Refined Detection
Multiresolution-based potential characters detection
• Laplacian-of-Guassian Edge Detection• Dice image/edges into Patches– Combine patches with similar properties into
regions– Obtain bounding box of region as candidate text– Properties include:• Mean• Variance• Intensity(?)
Multiresolution-based potential characters detection
Multiresolution-based potential characters detectionPatches qualify if:
Multiresolution-based potential characters detection
Multiresolution-based potential characters detection
Multiresolution-based potential characters detection
STR Implementation
• Possible Solutions:– Don’t grow bounding box. Grow non-rectangular
region, then obtain bounding box– Or replace with off-the-shelf Text Detector
blackbox (?)
Next Steps
• Email for STR implementations• Backtrack: Implement ‘crude’ STR
• Continue with current STR implementation
Text Detection Orthorectification
Increase Contrast/Binarization OCR Detected
Text
Thank You