Edge detection for PPM images

Description

Netpbm formats are image file formats designed to be easily exchanged between platforms: PPM (P3 P6), PGM (P2 P5), PNM (P1 P4).

Sobel operator is special edge detecting algorithm invented by Irwin Sobel and Gary Feldman

Project overview

This project is implementation of parallel sobel operator for ppm images. Program reads PPM (P3/P6) image from file, applies sobel and saves it in PPM or PGM(P2/P5) format

Libraries:
ppm.h - image structs & file operations: read PPM image, save to PPM/PGM
sobel.h - image processing: converting rgb to grayscale(and back), applying sobel operator to grayscale images

Building & Running

Requirements: make, gcc utilites
Builing project is pretty simple: first create build directory(mkdir build) , then run make in project's root folder - this command wil create executable netpbm-sobel in build folder.
Running project:

1. Go to build directory: cd build
2. Configuration for running is ./netpbm-sobel -i [input_file_path] -o [output_file_path] (-s [result file mode(P2/P3/P5/P6)] -t [number of threads (from 1 to 16)])
   By default one thread is used and saving mode is P2 (PGM)

• Example of running the project with engine image from test directory and saving it as P5 grayscale image:
  ./netpbm-sobel -i ../tests/engine.ppm -o ../tests/result.ppm -s P5 -t 4

Notes

• Please ensure that #comments are absent in input image file