Assignment 3

CPS 563 - Data Visualization

Requirements

In this assignment, you will solve practical and interesting problems in data visualization. The problems will gain valuable hands-on experience in data manipulation, data visualization, algorithm design and implementation.

Problem Description

You are provided the “Data.zip” file with two folders “Alphabets”, “Test” and “spider_plot” function after the file decompression. Each image in the two folders is in png format.

1. You resize all images in both folder to the size of 64x64 and convert them to grayscale images

(hint: use imresize and rgb2gray functions). 

2. For each resized image (64x64) in the “Test” folder, you plot the test image with the most similar image in the “Alphabets” folder (hint: you concatenate all image pixels to form 4096-dimension feature for each image. Then you compute the distance between each test image and all Alphabets images. Next, you plot the Alphabets image with the smallest distance to the test image).
3. For all resized images (64x64) in the “Alphabets” folder, you are required to perform Principal Component Analysis (PCA). Visualize the first 20 eigenvectors obtained from PCA (hint: use subplot function in MATLAB). 
4. You use 20 eigenvectors obtained from Question c to project all resized images (64x64) in the “Alphabets” and “Test” folders to 20-dimension space. In 20-dimension space, you are asked

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to plot each test image with the most similar image in the “Alphabets” folder (hint: Here each image has 20-dimension feature after PCA. Then you compute the distance between each test image and all Alphabets images. Finally, you plot the Alphabets image with the smallest distance to the test image).

5. For each resized image (64x64) in the “Test” folder, you project it to principal components obtained from PCA (in Question c), and then you utilize Radar Chart (hint: you use the given spider_plot function), to visualize all images in the “Test” folder with the first 5 components.

What to Submit

1. You must submit your program source code that implements the problems in the Assignment 3. 

For each group, you must submit the files above in a single zipped folder named after your student IDs. Note: If you cannot submit zipped file to isidore, please change the filename extension from .zip to . doc or .docx or .z1 and then submit it