Mathematics in Everyday Life

Mathematics in Everyday Life : 

Mathematics in Everyday Life Gilad Lerman Department of Mathematics University of Minnesota Highland park elementary (6th graders)

What do mathematicians do? : 

What do mathematicians do? What homework do I give my students? Example of a recent homework: Denoising

What do mathematicians do? : 

What do mathematicians do? What projects do I assign my students? Example of a recent project: Recognizing Panoramas Panorama: How to obtain a panorama? wide view of a physical space

How to obtain a panorama : 

How to obtain a panorama By “rotating line camera” Stitching together multiple images Your camera can do it this way… E.g. PhotoStitch (Canon PowerShot SD600)

Experiment with PhotoStitch : 

Experiment with PhotoStitch Experiment done by Rebecca Szarkowski Input: 10 images along a bridge

Experiment continued… : 

Experiment continued… Experiment done by Rebecca Szarkowski Output: Panorama (PhotoStitch) Output: Panorama (by a more careful mathematical algorithm)

What’s math got to do with it? : 

What’s math got to do with it? From visual images to numbers (or digital images) New Topic: Relation of Imaging and Mathematics

Slide 8: 

Digital Image Acquisition

From Numbers to Images : 

From Numbers to Images Let us type the following numbers 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 6 6 6 6 6 6 6 6 7 7 7 7 7 7 7 7 8 8 8 8 8 8 8 8 We then color them so 1=black, 8=white rest of colors are in between

One more time… : 

One more time… Now we’ll try the following numbers 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 4 4 4 4 4 4 4 4 8 8 8 8 8 8 8 8 16 16 16 16 16 16 16 16 32 32 32 32 32 32 32 32 64 64 64 64 64 64 64 64 128 128 128 128 128 128 128 128 We then color them so 1=black, 128=white rest of colors are in between

Let’s compare : 

Let’s compare 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 6 6 6 6 6 6 6 6 7 7 7 7 7 7 7 7 8 8 8 8 8 8 8 8 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 4 4 4 4 4 4 4 4 8 8 8 8 8 8 8 8 16 16 16 16 16 16 16 16 32 32 32 32 32 32 32 32 64 64 64 64 64 64 64 64 128 128 128 128 128 128 128 128

From an Image to Its Numbers : 

From an Image to Its Numbers We start with clown image It has 200*320 numbers I can’t show you all… Let’s zoom on eye (~40*50)

Image to Numbers (Continued) : 

Image to Numbers (Continued) We’ll zoom on middle of eye image (10*10)

The Numbers (Continued) : 

The Numbers (Continued) The middle of eye image (10*10) 80 81 80 80 80 80 77 77 37 11 81 80 81 80 80 80 77 37 9 6 80 80 80 80 80 80 37 11 2 11 80 80 80 80 80 77 66 66 66 54 80 80 80 80 77 77 77 80 77 80 80 80 79 77 66 54 66 77 66 54 77 80 77 70 22 57 51 70 51 70 77 73 70 22 2 2 22 37 37 22 77 77 54 37 1 6 2 8 2 6 77 70 70 22 2 2 6 8 8 6 Note the rule: Bright colors – high numbers Dark colors - low numbers

More Relation of Imaging and Math : 

More Relation of Imaging and Math Averaging numbers  smoothing images Idea of averaging: take an image Replace each point by average with its neighbors For example, 2 has the neighborhood So replace 2 by 80 81 80 80 80 80 77 77 37 11 81 80 81 80 80 80 77 37 9 6 80 80 80 80 80 80 37 11 2 11 80 80 80 80 80 77 66 66 66 54 80 80 80 80 77 77 77 80 77 80 80 80 79 77 66 54 66 77 66 54 77 80 77 70 22 57 51 70 51 70 77 73 70 22 2 2 22 37 37 22 77 77 54 37 1 6 2 8 2 6 77 70 70 22 2 2 6 8 8 6 70 22 57 22 2 2 37 1 6 80 81 80 80 80 80 77 77 37 11 81 80 81 80 80 80 77 37 9 6 80 80 80 80 80 80 37 11 2 11 80 80 80 80 80 77 66 66 66 54 80 80 80 80 77 77 77 80 77 80 80 80 79 77 66 54 66 77 66 54 77 80 77 70 22 57 51 70 51 70 77 73 70 22 2 2 22 37 37 22 77 77 54 37 1 6 2 8 2 6 77 70 70 22 2 2 6 8 8 6

Slide 16: 

Example: Smoothing by averaging Original image on top left It is then averaged with neighbors of distances 3, 5, 19, 15, 35, 45

Slide 17: 

Example: Smoothing by averaging And removing wrinkles by both….

More Relation of Imaging and Math : 

More Relation of Imaging and Math Differences of numbers  sharpening images On left image of moon On right its edges (obtained by differences) We can add the two to get a sharpened version of the first

Slide 19: 

Moon sharpening (continued)

Real Life Applications : 

Real Life Applications Many… From a Minnesota based company… Their main job: maintaining railroads Main concern: Identify cracks in railroads, before too late…

How to detect damaged rails? : 

How to detect damaged rails? Traditionally… drive along the rail (very long) and inspect Very easy to miss defects (falling asleep…) New technology: getting pictures of rails

Millions of images then collected : 

Millions of images then collected

How to detect Cracks? : 

How to detect Cracks? Human observation… Train a computer… Recall that differences detect edges… Work done by Kyle Heuton (high school student at Saint Paul)

Summary : 

Summary Math is useful (beyond the grocery store) Images are composed of numbers Good math ideas  good image processing