Streaming Architecture

Live HLS Streaming Architecture

How It Works

FadCam streams live video via HLS using a patched Media3 library that provides real-time fragment callbacks - no file polling needed.

Camera → GLRecordingPipeline → FragmentedMp4Muxer → Callback
                                                        ↓
                                              RemoteStreamManager
                                              (circular buffer)
                                                        ↓
                                              LiveM3U8Server
                                              (HTTP streaming)
                                                        ↓
                                              Browser/VLC Player

Key Components

Component	Purpose
FragmentedMp4MuxerWrapper	Muxes video into fMP4 fragments with real-time callbacks
ProcessedSegment	Media3 object containing init segment or media fragment
RemoteStreamManager	Circular buffer (10 fragments) for HLS streaming
LiveM3U8Server	HTTP server serving M3U8 playlists and fragments

Fragment Flow

1. Init Segment (ftyp + moov) sent first
2. Media Fragments (moof + mdat) sent every 2 seconds
3. Buffer stores latest 10 fragments (~20 seconds of video)
4. HTTP Server serves /live.m3u8 and /seg-{id}.m4s
5. Player streams video from device

Streaming Quality

• Codec: H.264 video, AAC audio
• Resolution: 1080p @ 30fps
• Fragment Duration: 2 seconds
• Latency: 3-4 seconds (2x fragment + buffer)
• Bitrate: 8-12 Mbps

Files

• FragmentedMp4MuxerWrapper.java - Muxer with callback integration
• RemoteStreamManager.java - Fragment buffer & HLS state
• LiveM3U8Server.java - HTTP endpoint for streaming
• GLRecordingPipeline.java - Camera → Muxer integration