H.264 / WebRTC

H.264 Video

About H.264

H.264 (also called MPEG-4 AVC) is an efficient video compression standard widely used for streaming. Compared to MJPEG, H.264 offers:

• Lower bandwidth usage
• Better compression efficiency
• Audio support
• Lower latency

Implementation Options

One-KVM provides two H.264 encoding options:

Libx264 (Recommended)

Libx264 is a high-performance H.264 encoder by VideoLAN. This option:

• Is integrated and enabled by default in recent versions
• Performs well and is easy to use
• Supports real-time WebRTC streaming
• Source code is available in the ustreamer branch

FFmpeg (EOL)

This option uses FFmpeg software encoding and is no longer maintained due to performance issues:

• High CPU usage
• Poor experience on low-performance devices
• Kept for historical reference only

WebRTC Configuration

WebRTC

WebRTC uses P2P connections and UDP transport to:

• Reduce latency
• Lower server load
• Improve real-time performance

Default configuration

WebRTC uses Google's STUN server by default. The config is in /etc/kvmd/override.yaml:

janus:
    stun:
        host: stun.l.google.com
        port: 19302
        retries: 5
        retries_delay: 5.0
        timeout: 5.0

Remote access

Two options are supported:

1. Port mapping (not recommended)

   • Requires mapping UDP ports 20000-40000
   • Complex and less secure

   

2. Mesh networking (recommended)

   • Use tools like Tailscale to build a secure tunnel
   • Simple and more secure
   • No need to map large port ranges

   

Video Quality Tuning

Quality tuning

If video quality is not ideal, try:

1. Adjust H.264 bitrate in the top-right system menu
2. Adjust resolution based on network conditions
3. Choose a suitable quality preset

Demo Video