Image filters and effects are applied to a BMP24 image file both sequentially and in parallel using POSIX threads. The program accepts an image as input, reads it through the fully implemented Bmp class bmp.hpp, and applies the desired filters, which are defined within the filter namespace filter.hpp.
Each filter operates on a BmpView, which is a custom view of the original Bmp (this could be the entire image by default), and modifies the original image pixels.
In the provided example main.cpp, three filters—vertical flip, Gaussian blur, and purple haze—are applied, and the result is saved as output.bmp.
For the parallel version, a thread pool is implemented using pthreads. Tasks are added to a mutex-protected queue, which are then executed by threads. In the example main.cpp, the image is divided into 8 BmpViews (one for each thread), and the filter tasks are executed concurrently by the threads.
To run the program:
./ImageFilters.out <Input_Image>