The primary goal of this assignment is to help you familiarize with Imperative Programming.

You will learn to:

$$ use simple structures.

$$ Dynamically allocate memory.

$$ Write functions.

$$ Implement pointes and references.

$$ Read from and write to files.

You can write your program either on EDORAS server or CLION IDE. CLION IDE is

recommended.

In this program, you will read and manipulate grayscale images. Download the given

starter$\_$code.c and implement the missing functions.

Program outline:

$1.$ Your C program should read any given grayscale images in pgm format. Grayscale images

have pixel values ranging from $0-255.$ This pixel values can be treated as unsigned

characters.

$2.$ The image data should be loaded as a $2$D matrix.

$3.$ The $2$D matrix should be manipulated to threshold the given image and convert it to a

binary image.

$4.$ The $2$D matrix should be manipulated to rotate the given image left.

$5.$ The manipulated $2$D matrices should be converted back to grayscale image. This image

should be viewable.

Your tasks: $($READ CAREFULLY$)$

$1.$ I would suggest you to open the file Lenna.pgm with your text editor available on your pc

to see how the headers look like. Please do not alter the file because in autograder it will

only use your code to alter the pgm file that we have on gradescope.

$2.$ DO NOT alter the main$()$ function. Four functions are declared and called in the given

program. Your task is to write the function definitions for the provided functions.

$3.$ PixelGray$**$ readPGM$($const char$*$ filename, int$*$ width, int$*$ height$)$;

a$.$ This function should open the file with provided file name.

i$.$ Note: If you use MacOS, it is okay to have the mode in $$r$.$ If you are using

Windows, you must have the mode to $$rb$.$

b$.$ Handle errors!

c$.$ Get the dimensions of the image.

d$.$ DO NOT SKIP THIS STEP, figure out how to $$eat$$ the newline character after

getting the last line of the headers.

e$.$ Dynamically allocate the storage $(2$D matrix$)$ for the image dimension.

f$.$ Read from the file and fill the $2$D matrix.

g$.$ Close the file.

h$.$ Return the $2$D matrix.

$4.$ void writePGM$($const char$*$ filename, PixelGray$**$ matrix, int$*$ width, int$*$ height$)$;

a$.$ This function should create a new file with the file name provided. This file should

be opened for writing.

b$.$ Remember there are headers from the original file. Think about how you will write

them to the file before passing the data from the matrix.

i$.$ Note: Autograder on gradescope will check line by line so I would leave no

space after passing your headers beside newline at the end of the last header

entry.

c$.$ Handle errors!

d$.$ Copy data from the provided $2$D matrix to the file.

e$.$ Close the file.

f$.$

$5.$ PixelGray$**$ threshold$($PixelGray$**$ matrix, int$*$ width, int$*$ height$)$;

a$.$ This function should create a new $2$D matrix. Dynamically allocate the storage $(2$D

matrix$)$ for the new matrix.

b$.$ Thresholding

i$.$ If original value $>80--$ store $255$

ii$.$ Otherwise $$ store $0$

c$.$ Return the new $2$D matrix.

$6.$ PixelGray$**$ rotate$($PixelGray$**$ matrix, int$*$ width, int$*$ height$)$;

a$.$ This function should create a new $2$D matrix. Dynamically allocate the storage $(2$D

matrix$)$ for the new matrix.

b$.$ Rotate the original $2$D matrix and store the result as