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fp:assig-02 [2021/05/14 21:07]
dmihai created 		fp:assig-02 [2021/05/28 11:05] (current)
dmihai
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-**Deadline: May 28th, 23:55**+**Deadline: May 31th, 23:55**
  
 ===== Introduction ===== ===== Introduction =====
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 ===== 1. Common transformations (0.4p) ===== ===== 1. Common transformations (0.4p) =====
  
-1.1. **scaling**+1.1. **scaling ​(0.2p)**
   * Scaling takes two factors (vertical and horizontal) and produces a new image with dimensions equal to that of the original multiplied by the given factor; scaling an image with height ''​h''​ and width ''​w''​ with a vertical factor ''​vf''​ and an horizontal factor ''​hf''​ results in a new image with height ''​h * vf''​ and width ''​w * hf''​.   * Scaling takes two factors (vertical and horizontal) and produces a new image with dimensions equal to that of the original multiplied by the given factor; scaling an image with height ''​h''​ and width ''​w''​ with a vertical factor ''​vf''​ and an horizontal factor ''​hf''​ results in a new image with height ''​h * vf''​ and width ''​w * hf''​.
   * We will employ a very simple scaling method: ​   * We will employ a very simple scaling method: ​
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   * With a vertical scaling factor of ''​1.25''​ you should duplicate every fourth line   * With a vertical scaling factor of ''​1.25''​ you should duplicate every fourth line
  
-1.2. **stamping**+1.2. **stamping ​(0.2p)**
   * We want to paste a small version of an image on top of another one   * We want to paste a small version of an image on top of another one
   * Your function takes a target image, a stamp image, the coordinates of the stamp'​s top-left corner and a scaling factor (hint: you should apply ''​scale''​ on it)   * Your function takes a target image, a stamp image, the coordinates of the stamp'​s top-left corner and a scaling factor (hint: you should apply ''​scale''​ on it)
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 ===== 2. Type-specific transformations (0.6p) ===== ===== 2. Type-specific transformations (0.6p) =====
  
-2.1 **superimposition**+2.1 **superimposition ​(0.15p)**
   * Superimposing an image on top of another with a transparency factor ''​alpha''​ (between ''​0''​ and ''​1''​) means combining the values of each corresponding pixel pairs using weights ''​alpha''​ and (1 - ''​alpha''​)   * Superimposing an image on top of another with a transparency factor ''​alpha''​ (between ''​0''​ and ''​1''​) means combining the values of each corresponding pixel pairs using weights ''​alpha''​ and (1 - ''​alpha''​)
   * For example, the result of superimposing the second image on top of the first with a transparency factor of 0.3 is:   * For example, the result of superimposing the second image on top of the first with a transparency factor of 0.3 is:
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 {{:​fp:​superimposeex.png?​750|}} {{:​fp:​superimposeex.png?​750|}}
  
-2.2 **contrast**+2.2 **contrast ​(0.15p)**
   * We want to adjust the contrast of an image with a contrast factor.   * We want to adjust the contrast of an image with a contrast factor.
   * You can use the algorithm presented [[https://​www.dfstudios.co.uk/​articles/​programming/​image-programming-algorithms/​image-processing-algorithms-part-5-contrast-adjustment/​|here]]:​ given a contrast level ''​c'',​ you first calculate a correction factor: $math[f = \frac{259\cdot(c + 255)}{255\cdot(259 - c)}]; then, for each pixel you change its color value to $math[f\cdot(oldValue - 128) + 128] (for RGB images, you need to this on all three color channels).   * You can use the algorithm presented [[https://​www.dfstudios.co.uk/​articles/​programming/​image-programming-algorithms/​image-processing-algorithms-part-5-contrast-adjustment/​|here]]:​ given a contrast level ''​c'',​ you first calculate a correction factor: $math[f = \frac{259\cdot(c + 255)}{255\cdot(259 - c)}]; then, for each pixel you change its color value to $math[f\cdot(oldValue - 128) + 128] (for RGB images, you need to this on all three color channels).
   * Also make sure that all resulting new values are in the range 0-255!   * Also make sure that all resulting new values are in the range 0-255!
  
-2.3 **bordering**+2.3 **bordering ​(0.15p)**
   * Add a solid border with a given thickness around the image, on each side   * Add a solid border with a given thickness around the image, on each side
   * The color of the border should be the average color of the image (so you need to calculate that first)   * The color of the border should be the average color of the image (so you need to calculate that first)
  
-2.4 **blur**+2.4 **blur ​(0.15p)**
   * We will implement the simplest form of blurring: each new pixel will be the arithmetic mean of the original pixel and the pixel directly below it.   * We will implement the simplest form of blurring: each new pixel will be the arithmetic mean of the original pixel and the pixel directly below it.
   * For the last line, for which there are no pixels below, you can use any of these approaches:   * For the last line, for which there are no pixels below, you can use any of these approaches:
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 ==== Submission ==== ==== Submission ====
  
-For submission ​you should create a zip archive of the three files you modified: ''​Common.hs'',​ ''​Greyscale.hs''​ and ''​Color.hs''​ and a ''​README''​. The ''​README''​ should contain a succinct high-level presentation of your work. The archive name should be ''​LASTNAME_Firstname_FP_A1.zip''​ (if you have multiple firstnames, separate them by an underline "​_"​). Upload ​it to TODO+For submitting ​you should create a zip archive of the three files you modified: ''​Common.hs'',​ ''​Greyscale.hs''​ and ''​Color.hs''​ and a ''​README''​. The ''​README''​ should contain a succinct high-level presentation of your work. The archive name should be ''​LASTNAME_Firstname_FP_A1.zip''​ (if you have multiple firstnames, separate them by an underline "​_"​). Upload ​the archive ​to [[https://​curs.upb.ro/​mod/​assign/​view.php?​id=300279|the corresponding activity]] on moodle.