NYT crossword puzzle solver 5. Mai 2016 1 NYT crossword puzzle solver
2 NYT crossword puzzle solver
1 Problem Description 2 Concept of Solution 3 Grid extraction 4 Box Classification 5 Solve puzzle 6 Results 3 NYT crossword puzzle solver
Problem Description Puzzle is a regular grid of quadratic boxes Box types I Empty Boxes II Numbered Boxes (include reference to hints) III Structure Boxes (entirely black) Assumption clues are known digitally project focused on image processing 4 NYT crossword puzzle solver
Problem Description Puzzle is a regular grid of quadratic boxes Box types I Empty Boxes II Numbered Boxes (include reference to hints) III Structure Boxes (entirely black) Assumption clues are known digitally project focused on image processing 4 NYT crossword puzzle solver
Problem Description Puzzle is a regular grid of quadratic boxes Box types I Empty Boxes II Numbered Boxes (include reference to hints) III Structure Boxes (entirely black) Assumption clues are known digitally project focused on image processing 4 NYT crossword puzzle solver
Concept of Solution Outline 1 Grid extraction image preprocessing extract lines find largest rectangle rectification grid validation box extraction 2 box classification 3 solve puzzle determine length of fitting words solve individual clues insert solutions 5 NYT crossword puzzle solver
Image preprocessing adaptive threshold filtered binary image 6 NYT crossword puzzle solver
Line extraction Hough transformation Clustering by θ Assumption: two largest clusters span the grid detected and clustered lines 7 NYT crossword puzzle solver
Find largest rectangle Problem Rectangle way too large Fortunately, detected lines are parallel to grid shrink rectangle Detected rectangle 8 NYT crossword puzzle solver
Grid validation Shrinkage based on row and column sums Peaks correspond to row and column numbers Warped binary image 1200 1000 800 sum white pixel 600 400 200 0 0 200 400 600 800 1000 1200 1400 1600 columns 9 NYT crossword puzzle solver
Problem Description Concept of Solution Grid extraction Box Classification Box extraction Back projection of Rectified grid cropped corner points Rectification based on DLT each box on regular grid just use a pair of scissors :) 10 NYT crossword puzzle solver Solve puzzle Results
Box classification Just consider the amount of black pixels within one box Structure Boxes: > 30% Empty Boxes: < 1% Numbered Boxes: remaining Mirror grid if numbers are not located in the top left corner Rectified binary grid 11 NYT crossword puzzle solver
Clue grid Assign numbers to numbered boxes Link numbered boxes with clues Determine length of solution Solve individual clues Send query to crossword puzzle solvers on the web and extract possible answers. Inset Solutions 1 Insert clues with single solution 2 Use letters in the grid to solve clues with multiple solutions 12 NYT crossword puzzle solver
Solution Back projection of solution 13 NYT crossword puzzle solver
Problem Description Concept of Solution Grid extraction Box Classification Limits of Algorithm (1) grid + pens 14 detected lines NYT crossword puzzle solver Solve puzzle Results
Problem Description Concept of Solution Grid extraction Box Classification Limits of Algorithm (2) Detected largest rectangle 15 Rectified grid NYT crossword puzzle solver Solve puzzle Results
Thank you for your attention! 16 NYT crossword puzzle solver