CSE 241 Programming Assignment 2 Solved

This assignment is the first in a series of assignments which are all going to be about classes. In the end, you will have an image editor which is implemented with basic object oriented design principles kept in mind.

Your should utilize object oriented principles as much as possible. Your submission may not be accepted if you ignore this advice.

Image Editor

    • You can create a class which represents the whole image editor program. Your program won’t have a GUI yet and you need to do is decide how to organize events and data in your program.
    • Implement a menu system.

    • Implement member functions for reading image files and writing image data to files.

    • Currently, your image editor program opens only one image and operates on it. Later, you will extend your program to open more than one image at a time.
    • Implement grayscale conversion function.

Image File Format

Your program will basically work on PPM format(Ascii format). Particularly P3 format. Read the description here:

http://netpbm.sourceforge.net/doc/ppm.html

Many image editors can read and write ppm files. I advise you to use GIMP. Use Ascii format while exporting, otherwise you cannot read it.

Menu Of Your Program

The initial version of your program will have the following main menu structure:

Main Menu

0
- Exit
-----> Exits the program without saving the image data
1
- Open An Image(D)
-----> A dialog entity in order for user to enter a file name.
2
- Save Image Data(D)
-----> A dialog entity for saving the current state of the image data.
3
- Scripts(D)
-----> Various scripts

OPEN AN IMAGE MENU

0-UP

1 - Enter The Name Of The Image File

SAVE IMAGE DATA MENU

0-UP

1 - Enter A File Name

SCRIPTS MENU

0-UP

1 - Convert To Grayscale(D)

CONVERT TO GRAYSCALE MENU

0-UP

1 - Enter Coefficients For RED GREEN And BLUE Channels.


1
If a menu item has a (D) at the end, that means it is a dialog. If user enter the particular menu number, A new menu dialog will be shown.

Example

Suppose that you have the following file.

    • test.ppm

P3











4
4










255










0
0
0
100 0
0
0
0
0
255
0
255
0
0
0
0
255
175
0
0
0
0
0
0
0
0
0
0
0
0
0
15
175
0
0
0
255
0 255
0
0
0
0
0
0
255
255
255

NOTE: > is a part of the terminal environment. DO NOT PRINT IT Start your program

> ./myprogram

> MAIN MENU

> 0 - Exit

> 1 - Open An Image(D)

> 2 - Save Image Data(D)

> 3 - Scripts(D)

> 1    --------> User inputs 1 and presses RETURN

> OPEN AN IMAGE MENU

> 0 - UP    --------> If user enters 0, MAIN MENU will be printed.

> 1 - Enter The Name Of The Image File

> 1    --------> User inputs 1 and presses RETURN

> test.ppm    --------> User inputs test.ppm and presses RETURN

> OPEN AN IMAGE MENU    --------> Your program reads test.ppm and prints the current dialog menu

> 0 - UP    --------> If user enters 0, MAIN MENU will be printed.

> 1 - Enter The Name Of The Image File

> 0    --------> User inputs 0 and presses RETURN

> MAIN MENU    --------> MAIN MENU is printed again

> 0 - Exit

> 1 - Open An Image(D)

> 2 - Save Image Data(D)

> 3 - Scripts(D)

.

.

.

Script: Convert To Grayscale

This script creates the following dialog:

CONVERT TO GRAYSCALE MENU

0-UP

1 - Enter Coefficients For RED GREEN And BLUE Channels.

If user enters 1, then user can enter three float numbers which are in the range [0,1). You should check for any errors. If there is an error, ask user to re-enter the coefficients. Example input:

0.33 0.10 0.2

These numbers are coefficients (c_r, c_g, c_b) for RED, GREEN and BLUE channels. After getting the coefficients (c_r, c_g, c_b) you can convert each color to grayscale using the following formula:

2
RED =    (c_r * RED) + (c_g * GREEN) + (c_b * BLUE)

GREEN =    (c_r * RED) + (c_g * GREEN) + (c_b * BLUE)

BLUE =    (c_r * RED) + (c_g * GREEN) + (c_b * BLUE)

You just need to update the values in the image representation these new values. If the new values are greater than 255, then that means they are saturated. Leave them as 255.

Saving Image Data

SAVE IMAGE DATA MENU

0-UP

1 - Enter A File Name

If user enters 1, then user can enter a filename. Example: Assume user enters output.ppm. In this case, image data in the memory will be saved as output.ppm.

Remarks

    • Error checking is important.

    • Your program should be immune to the whitespace before any user input.

    • Do not submit your code without testing it with several different scenarios.

    • Write comments in your code. Extensive commenting is required. Comment on every variable, constant, function and loop. (10pts)
    • Do not use #Define and define macros. Instead use constant keyword and define constant variables. If you use macros, you will loose 5 points for each of them.
    • Everything happens through stdin and stdout.

    • Be very careful about the input and output format. Don’t print anything extra(including spaces).

    • You have to use Class. You should not use inheritance and other advanced OOP mechanisms yet.

    • You can use std::string and std::vector.

Turn in:

    • Source code of a complete C++ program. Name of the file should be in this format: <full_name>_PA2.cpp. If you do not follow this naming convention you will loose -10 points.

    • Example: albert_einstein_PA2.cpp. Please do not use any Turkish special characters.

    • You don’t need to use an IDE for this assignment. Your code will be compiled and run in a command window.

    • Your code will be compiled and tested on a Linux machine(Ubuntu). GCC will be used.

    • Make sure you don’t get compile errors when you issue this command : g++ -std=c++11 <full_name>_PA2.cpp.

    • A script will be used in order to check the correctness of your results. So, be careful not to violate the expected output format.

    • Provide comments unless you are not interested in partial credit. (If I cannot easily understand your design, you may loose points.)
    • You may not get full credit if your implementation contradicts with the statements in this document.




















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Start






Exit    Main Menu

0 - Exit
 1 - Open An Image(D)

2 - Save Image Data(D)

3 - Scripts(D)







OPEN AN IMAGE MENU
SAVE IMAGE DATA MENU
SCRIPTS MENU
0
-
UP
0
-
UP
0
-
UP
1
-
Enter The Name Of
1
-
Enter A File Name
1
-
Convert To Grayscale(D)
The
Image File












-
create an image object
- save image object
CONVERT TO GRAYSCALE MENU
-
read ppm image data
data as ppm
0
-
UP



1
-
Enter Coefficients For



RED
GREEN And BLUE Channels.






- user enters R G B coefficients


- current image data is converted


to grayscale using R G B coefficients


Figure 1: Program Flow








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Late Submission

    • Not accepted.

Grading (Tentative)

    • Max Grade : 100.

    • Multiple tests will be performed.

All of the followings are possible deductions from Max Grade.

    • Do NOT use hard-coded values. If you use you will loose 10pts.

    • No submission: -100. (be consistent in doing this and your overall grade will converge to N/A) (To be specific: if you miss 3 assignments you’ll get N/A)

    • Compile errors: -100.

    • Irrelevant code: -100.

    • Major parts are missing: -100.

    • Unnecessarily long code: -30.

    • Inefficient implementation: -20.

    • Using language elements and libraries which are not allowed: -100.

    • Not caring about the structure and efficiency: -30. (avoid using hard-coded values, avoid hard-to-follow expressions, avoid code repetition, avoid unnecessary loops).

    • Significant number of compiler warnings: -10.

    • Not commented enough: -10. (Comments are in English. Turkish comments are not accepted).

    • Source code encoding is not UTF-8 and characters are not properly displayed: -5. (You can use ‘Visual Studio Code’, ‘Sublime Text’, ‘Atom’ etc. . . Check the character encoding of your text editor and set it to UTF-8).
    • Cannot properly print the menu: -5 for each test.

    • Cannot execute menu commands: Fails the test.

    • Output format is wrong: -30.

    • Infinite loop: Fails the test.

    • Segmentation fault: Fails the test.

    • Fails 5 or more random tests: -100.

    • Fails the test: deduction up to 20.

    • Prints anything extra: -30.

    • Unwanted chars and spaces in output: -30.

    • Submission includes files other than the expected: -10.

    • Submission does not follow the file naming convention: -10.

    • Sharing or inheriting code: -200.












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