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Farabi Hasan Harija Yalamanchi

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<strong>Farabi</strong> <strong>Hasan</strong><br />

<strong>Harija</strong> <strong>Yalamanchi</strong>


• Object Recognition<br />

• Face Recognition<br />

• Optical Character Recognition


Object Recognition using<br />

Eigenspace<br />

Template matching problem<br />

The idea is to represent image onto a<br />

lower dimensional space


Preliminaries<br />

Objects should be centered in the image<br />

Constant background<br />

Square matrix<br />

Illumination conditions


Algorithm<br />

1. Obtain training images I1, I2…IM for the database with<br />

different angles and different lighting conditions.<br />

2. Calculate the mean image<br />

3. Normalize each image by subtracting the mean image<br />

4. Create a matrix A = [Φ1 Φ2 . . . ΦM] where Φ is<br />

normalized image<br />

5. Compute first few eigenvectors of A as they contain the<br />

most important information<br />

6. Each normalized face Φ i in the training set can be<br />

represented as a linear combination of these<br />

eigenvectors


7. Each normalized training face Φi is represented in<br />

the basis by a vector<br />

8. Obtain the test image<br />

9. Subtract the mean image from the test image<br />

10. Compare the Euclidean distance and<br />

11. These distances show how far/close the test image is<br />

from the database of images


Results for Object Recognition<br />

Database of images used:


Distances for a cup:<br />

d1 = 296.4598<br />

d2 = 1.4176e+003<br />

d3 = 1.0786e+003<br />

d4 = 99.3106<br />

d5 = 1.2149e+003<br />

Distances for a box:<br />

d11 = 1.4838e+003<br />

d12 = 3.1979e+003<br />

d13 = 2.8589e+003<br />

d14 = 1.6810e+003<br />

d15 = 2.9952e+003


Very similar algorithm!<br />

Minor differences


Distances:<br />

d1 = 246.7174<br />

d2 = 806.5047<br />

d3 = 246.7174<br />

d4 = 5.0179e+003<br />

d5 = 5.1997e+003<br />

d6 = 4.9331e+003<br />

d7 = 1.3278e+003<br />

d8 = 1.3006e+003<br />

d9 = 1.3448e+003<br />

Distances:<br />

d1 = 2.9477e+003<br />

d2 = 2.3879e+003<br />

d3 = 2.9477e+003<br />

d4 = 1.8235e+003<br />

d5 = 2.0053e+003<br />

d6 = 1.7387e+003<br />

d7 = 4.5222e+003<br />

d8 = 4.4950e+003<br />

d9 = 4.5392e+003


Distances:<br />

d1 = 2.3897e+003<br />

d2 = 2.7448e+003<br />

d3 = 178.2691<br />

d4 = 314.1939<br />

d5 = 4.4594e+003<br />

Distances:<br />

d1 = 2.0783e+003<br />

d2 = 1.7233e+003<br />

d3 = 4.6463e+003<br />

d4 = 4.7822e+003<br />

d5 = 8.6497


Similar Algorithm


Database<br />

Each letter and number is represented as a .bmp<br />

file.<br />

…<br />


Drivers License<br />

Verify age of license holder


Steps to OCR<br />

1. Take picture of license<br />

2. Crop DOB<br />

3. Create edge view<br />

4. Clip the image horizontally<br />

5. Clip the segmented image vertically<br />

6. Use Matlab’s corr2() function to find the<br />

correlation of the current character to the<br />

characters in the database


Steps (cont…)<br />

7. Find the character in the database with the highest<br />

correlation to the current character and store the<br />

value<br />

8. Print the value in text file<br />

9. Verify Age


Practical Uses<br />

Using recognition<br />

Verify a person’s face from database<br />

Using OCR<br />

Verify that the person is of legal age to drink, smoke,<br />

etc..<br />

Identification checker and if camera available, verify<br />

the person on the license is the same person in real<br />

life<br />

Reducing Fake ID usage


References:<br />

http://www.cse.unr.edu/~bebis/CS791E/Notes/<br />

http://www.cs.ait.ac.th/~mdailey/matlab/<br />

http://cswww.essex.ac.uk/mv/allfaces/faces94.html<br />

http://www.ele.uri.edu/~hansenj/projects/ele585/OCR<br />

http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?<br />

objectId=18169&objectType=file

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