[Coding Exercise] Week 10 - Interactive image processor

7/17/22, 1:28 PM [Coding Exercise] Week 10 - Interactive image processor https://canvas.sfu.ca/courses/70584/assignments/783867?module_item_id=2570336 1/6 [Coding Exercise] Week 10 - Interactive image processor Due Jul 25 by 11:59p.m. Points 18 Submitting a file upload File Types zip Available until Jul 27 at 11:59p.m. Start Assignment You are going to process a very recent image captured by the James Webb telescope, released on July 12 2022!! Create an interactive program that performs 4 image manipulations on an image [ ngc3132.jpg ] (width = 600, height = 555) of the Southern Ring Nebula as seen by the James Webb Telescope. Credit: NASA, ESA, CSA, and STScI. The program must: Take user input (0/1/2/3/4) using a while-loop to determine which manipulation options (1/2/3/4) they want to apply. If the user enters 0, the program ends If the user enters 1/2/3 or 4, perform the manipulation, then save the resulting image as a new image under the name result-optionX.jpg where X is the user input option. For example, result- option1.jpg should contain the interlaced image. Once the manipulation and saving is done, the

7/17/22, 1:28 PM [Coding Exercise] Week 10 - Interactive image processor https://canvas.sfu.ca/courses/70584/assignments/783867?module_item_id=2570336 2/6 program asks the user for an input again. Optionally, the resulting image can also be shown to the user, but this is not required. If the user enters something other than the expected input (e.g., 37), display the message “Sorry, I don’t understand 37” and take the user input again. Each manipulation should be done on the original image. Define one function for each manipulation option : 1: interlace(pixels) – pixels is a parameter to the function, which will receive a 2D list of pixels representing an image, as seen in class. This function interlaces the image with black lines by blacking out (i.e. replacing every pixel with black) every second row . You should start with the first row (row 0). Sample output: Before After 2: invert(pixels) – inverts the colour of the image. To calculate the inverted colour of a pixel, its red, green, and blue components are replaced with 255-red, 255-green, and 255-blue , respectively. For example, if a pixel has [100, 150, 200] as its red, green, and blue components, its inverted colour will be [255-100, 255-150, 255-200], which is [155, 105, 55]. Sample output: Before After

7/17/22, 1:28 PM [Coding Exercise] Week 10 - Interactive image processor https://canvas.sfu.ca/courses/70584/assignments/783867?module_item_id=2570336 4/6 green, and blue components are each replaced with gs + factor*(red - gs ) , gs + factor*(green - gs ) , and gs + factor*(blue - gs ) . For example, if a pixel has [100, 150, 200] as its red, green, blue colour, the grayscale value is (100+150+200)/3 = 150. Then if you scale the saturation by 0.5 the new colour of this pixel will be [150 + 0.5*(100 - 150), 150 + 0.5*(150 - 150), 150 + 0.5* (200 - 150)], which evaluates to [125, 150, 175]. Note: your program will need to ask the user to input a scaling factor to use as the factor argument to this function. Hint: you will need to deal with overflow. Overflow occurs if the any of the red, green, or blue values fall outside of the range 0 to 255. If the red, green, or blue value is less than 0, it should be set to 0. Likewise, if it is greater than 255, it should be set to 255. Sample output: Before After scaling by a factor of 0.5 Before After scaling by a factor of 2

7/17/22, 1:28 PM [Coding Exercise] Week 10 - Interactive image processor https://canvas.sfu.ca/courses/70584/assignments/783867?module_item_id=2570336 5/6 Requirements Use a nested for-loop in each function to apply changes to the pixels. Each function doing a manipulation should return a 2D pixel array representing the resulting image, and which could later be used as argument when calling the functions cmpt120Image.saveImage(...) and cmpt120Image.showImage(...) . You are required to use cmpt120Image.saveImage(...) to save each resulting image but you are NOT required to use showimage(...), as it may not work correctly in some computers (although, if it works, it can be practical to show to the user to aid debugging). Here is the sample output of a portion of the interactive program: Welcome to Image Processor! Here are your options 0: Quit 1: Interlace with black lines 2: Invert the colour of the image 3: Convert the colour of the image into grayscale 4: Adjust the saturation Enter your choice (0/1/2/3/4): 2 OK... Image saved as result-option2.jpg Enter your choice (0/1/2/3/4): 4 How much should I adjust the saturation by? 0.5 OK... Image saved as result-option4.jpg Remember to design your algorithm in English first, then translate it to Python code. Test as you go! Notes For this exercise you will be indirectly using an image processing library (pygame) which is not natively available in IDLE. You can choose to use Replit ( https://replit.com (https://replit.com/) ) to do this exercise, or use another Python code editor called Mu ( https://codewith.mu/ (https://codewith.mu/) ). Both Replit and mu have the library built-in and is ready for use. Mu might try to open a new window to show you an image but it might not work on some computers. If you have a non-responsive image you can stop the execution. We have provided you with 4 functions ( getImage , saveImage , showImage , and getBlackImage ) in a separate Python module file named cmpt120image.py (https://canvas.sfu.ca/courses/70584/files/19436954/download?download_frd=1) . (thsi is the same file we used in class). Use it to help you with this exercise. Do not change anything in this file . You must put all your function definitions for the image manipulation options (invert, grayscale, etc.) in another Python module file named myImageManip.py . Each function takes in a 2D list containing all the pixels (and possibly other parameters) which should have been returned from the getImage(...) function. Refer to our lectures for details. Your Python code should import the module cmpt120image. You cannot use other libraries to manipulate images.