[js/lite] VideoEncoder fails on Linux without H.264 hardware encoding - needs software fallback #852
Description
Problem
The hang webapp's video encoder fails on Linux systems without hardware H.264 encoding support. The encoder tries High Profile (avc1.640028) first and fails with "Encoder creation error" instead of falling back to a software-compatible configuration.
Environment
- Linux (Ubuntu)
- Chrome with WebCodecs
- No hardware H.264 encoder available
Expected Behavior
The encoder should fall back to H.264 Baseline Profile with conservative settings that work with software encoding, similar to how the moxygen encoder does:
{
codec: 'avc1.42001e', // Baseline Profile, Level 3.0
width: 320,
height: 180,
bitrate: 1_000_000,
latencyMode: 'realtime'
}
Actual Behavior
The encoder tries these codecs in order and fails completely:
- avc1.640028 (High Profile, Level 4.0)
- avc1.4D401F (Main Profile, Level 3.1)
- avc1.42E01E (Baseline Profile, Level 3.0)
Error: Encoder creation error
Workaround
Patching the bundled JS to use avc1.42001e instead allows encoding to work.
Suggestion
Add fallback logic that:
1. Uses VideoEncoder.isConfigSupported() to test each codec/resolution combination
2. Falls back to simpler Baseline Profile configs when hardware encoding unavailable
3. Reduces resolution if needed for software encoding performance