Video Event Clipping System

Overview

This project implements a simple real-time video event clipping system in C++ using shared memory, sockets, multithreading, and OpenCV. The system contains four applications: 1.Video Processor Reads frames from a video file Shares frames through shared memory Maintains source FPS timing 2.Video Clipper Reads frames from shared memory Maintains a circular buffer for the previous 9 seconds Receives event notifications over socket Generates a 15-second clip: 9 seconds before event 6 seconds after event Saves clip as .mp4 3.Event Notifier User interactive application Sends event notification when user presses e 4.CPU Watcher Monitors system memory usage Monitors Video Clipper process usage

Requirements

•Linux •C++17 •OpenCV •CMake •POSIX shared memory

Design Highlights

•Shared memory based IPC •Mutex protected shared memory synchronization •Circular frame buffer using deque •Multi-threaded event processing •Graceful shutdown using SIGINT

References

•LearnOpenCV - Reading and Writing Videos using OpenCV •OpenCV Official Documentation •ChatGPT

Notes

•Sometimes process synchronization may fail and generate unusually large output files. •CPU usage printing is incomplete due to time limitations. •Shared memory synchronization uses pthread_mutex.

Compile

mkdir build cd build

cmake .. make

cd -

Run

Open four terminals and execute:

Terminal 1 ./build/video_processor Terminal 2 ./build/video_clipper Terminal 3 ./build/event_notifier Terminal 4 ./build/CPU_watcher Trigger Event

Inside event_notifier:

Press e + ENTER

Each event generates an independent video clip.

Output

Generated clips are saved as:

.mp4

Example:

1715578210.mp4