Worked on optimizing the DHAV demuxer in the ossrs/ffmpeg-webrtc repository to improve duration retrieval and seeking reliability for streaming scenarios. The approach involved buffering the last 1 MiB of data and performing byte-by-byte end-tag checks during backward scans, which reduced unnecessary seeks on truncated files and minimized HTTP requests for network streams. This enhancement improved startup latency and playback reliability for both live and on-demand content. The work required expertise in C, file I/O, and low-level programming within multimedia frameworks, demonstrating a focused effort on performance optimization and robust handling of incomplete or network-based media files.