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To get started on this assignment you will have to use any number of ways to covert a text array to an Image. There are lots of ways to do this so just google on text to array

Steps:

1. Download the two files
   
   
   • Stars
   • Galaxy
   
   
   
2. Before converting the 3 column text file into an image do these operations
   
   
   • Determinine the minimum and maximum intensities in the data (these are the values in the z column (column 3)
     
     
   • Determine how many pixels are saturated in this image (how many have values =65535)
     
     
   • Determine the amount of distinct intensity values (again numbers in the third column)
     
     
   • Determine the average pixel intensity in this data and compare that with the modal pixel intensity
   
   
   Report all these values in a table
   
   
3. Stars.txt is an image of a stellar cluster with a few number of stars in it. The 2D array size for the star data is 1124 lines x 1024 columns (the first 120 lines are garbage but keep them any way). Convert the 1D raw text file into the 2D array and. Submit the grayscale image of the text file to converted to a 2D image array
   
   
4. The stars image is a very short exposure image so the background is not well determined and has big fluctuations (which might appear as thousands of faint stars). The brightest stars have saturated the detector and have a column bled (bright white streaks).
   
   
   a) Write a new image file with those stars plus columns "masked out" in any way that you want to eliminate them.
   
   b) Using any procedure that you can think of, automatically determine the positions of the stars in the Stars image. Then using any procedure that you can think of, measure the integrated brightness (intensity) of these identified stars and submit a list of the 20 brightest stars listing their brightness and their X and Y positions
   
   c) Using the High charts Bubble Chart with JS Fiddle produce a bubble chart of those 20 stars showing the x,y center of the star and the radius of the bubble should correspond to the star's brightness
   
   
   Now you will use the Galaxy file - the dimensions of that file are slightly different than the other one. You have to determine them from the data. Again you will want to determine if there are saturated pixels and mask or delete them from the data.
   
   
5. submit a grey scale image of the Galaxy
   
   
6. From the center of the galaxy (identify that any way that you like) Compute the average brightness of the galaxy in annular rings of width 5 pixels and spaced by 20 pixels from the center to the edge and Make a plot of radius vs ring brightness and attempt to fit a functional representation of that relation to the data
   
   
7. Produce a histogram of the pixel values and suggest a reason for the particular form of the histogram
   
   
8. Make the Galaxy disappear. Using any random number generator approach that you like, make the galaxy disappear by adding sufficient random noise to the image. Submit the image of the disappeared galaxy