2023-02-03 00:54:50 +00:00
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# Assignment 0: Working with ASCII images
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2023-02-03 00:46:37 +00:00
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In this assignment, you are asked to write a program that creates an image in
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ASCII PPM format.
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Your program should accept, as a command line argument, the name of a file
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containing an "image description" (consisting of one line of text specifying the
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image height and image width, optionally followed other lines of text specifying
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any additional parameters your program might use), and it should generate a
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valid ASCII PPM file as output. The name of the output file should end with the
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suffix .ppm. Your program should be capable of accepting different input files
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and producing different output files without needing to be recompiled.
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You are free to use whatever means you like to define the contents of the output
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image. If you have time and are so inclined, you can earn extra credit by doing
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something creative. Possibilities include: hardcoding an interesting pattern,
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generating a [procedural texture][1], generating an image of the [Mandelbrot
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set][2], or reading an image from a file and applying an interesting [filter][3]
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or function such as [line integral convolution][4]. Whatever approach you
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choose, the code you turn in **must** be your own.
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[1]: https://en.wikipedia.org/wiki/Procedural_texture
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[2]: https://en.wikipedia.org/wiki/Mandelbrot_set
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[3]: https://en.wikipedia.org/wiki/Kernel_(image_processing)
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[4]: https://en.wikipedia.org/wiki/Line_integral_convolution
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2023-02-03 00:54:50 +00:00
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### Detailed instructions
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2023-02-03 00:46:37 +00:00
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1. Please use the following syntax to define the image size in your input file:
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imsize width height
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where imsize is a keyword and width and height are integers.
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2. Please use the following syntax to define your output image:
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P3
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# any comments you want to include
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width height
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255
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r(0,0) g(0,0) b(0,0) r(1,0) g(1,0) b(1,0) r(2,0) g(2,0) b(2,0) ...
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Please note that in an ASCII PPM file, each pixel color is defined as an (r, g,
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b) triple, and the provided values are used to fill the image in row major
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order. Specifically, the first three entries represent the red, green and blue
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components of the color of the upper leftmost pixel in the image, the second
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three entries represent the color of the adjacent pixel to the right, and so on.
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Your program will need to specify exactly one color triple for each pixel in
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your image. Try to keep the line length under 80 characters, or approximately
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4-5 pixels per line. It’s also okay to put each color component on its own line
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too. Do not insert any other characters such as commas, etc. between any of the
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color values.
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You can use the free program [GIMP] to view your image, to verify that it looks
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the way you intend it to. GIMP is a general-purpose image editing tool that can
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also be used to convert images from multiple other formats into ASCII PPM format
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(and vice versa).
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[gimp]: http://www.gimp.org
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2023-02-03 00:54:50 +00:00
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### What you should turn in
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2023-02-03 00:46:37 +00:00
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- a readme file that describes your what your program does
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- all of your source code, clearly commented
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- at least one ascii PPM image created by your program
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We will plan to share the PPM images in class. If you would prefer that we not
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show your image, please let us know.
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We will use this rubric: grading-criteria-0.pdf when grading your program. You
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are advised to check the rubric before beginning the assignment to fully
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understand how credit will be awarded.
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