Worked on the ossrs/ffmpeg-webrtc and FFmpeg/FFmpeg repositories, focusing on media workflow reliability and security. Developed and hardened signaling protocols by enforcing HTTP URL validation for SDP exchanges, and improved code maintainability by removing redundant AVPacket checks using C and AVFormat. Enhanced automated test coverage for HLS fMP4 encoding, updating build systems and integrating reference validation files to streamline CI and regression testing. Addressed stability in DASH streaming by validating and clamping MPD XML values in the DASH Demuxer, reducing crash risk. Demonstrated a methodical approach to protocol implementation, software debugging, and video processing, emphasizing robust, maintainable solutions.