Photo Filters and Memory using C

Homework from Harvard's Introduction to Computer Science CS50 hosted on eDX

🎓 Problem Set 4

• Filter: Apply grayscale, sepia, mirror, and blur filters to a bitmap (image)
• I wrote the code in helpers.c. The other files were provided by the instructor.

💡Lessons Learned

• Implementing knowledge of hexadecimals by altering individual pixel's RGB values to achieve the desired photo filter effect
• Iteration through a two dimensional array, specifically a 24-bit bitmap
• Using copy to save arrays into memory and to ultimately alter them
• Working with struct RGBTRIPLE and its parameters
• Analyzing BITMAPINFOHEADER and BITMAPFILEHEADER

🚀 Getting Started with Filter

To run this project locally:

• In your terminal, navigate to this folder's root directory and run the following commands

$ clang -fsanitize=signed-integer-overflow -fsanitize=undefined -ggdb3 -O0 -Qunused-arguments -std=c11 -Wall -Werror -Wextra -Wno-sign-compare -Wno-unused-parameter -Wno-unused-variable -Wshadow -o filter filter.c helpers.c

🕹 How to Use

• In your terminal, navigate to this folder's root directory and run the following command

$ ./filter -foo images/bar.bmp out.bmp

Where foo is the argument for grayscale, images/bar.bmp is one of 4 bitmaps found in the images directory, and out.bmp is the name of the filtered image that will be populated in the filter directory. In place of foo, use -g for grayscale, -s for sepia, -r for mirror, and -b for blur. In place of bar, use courtyard.bmp, stadium.bmp, tower.bmp, or yard.bmp, which may be found in the images directory. out.bmp is an arbitrary name for the outputted bmp file.

• Quick use examples

./filter -g images/tower.bmp grey.bmp
./filter -s images/tower.bmp sepia.bmp
./filter -r images/tower.bmp reverse.bmp