silk

WeChat voice messages are encoded with the SILK codec (originally developed by Skype). silk is a single-binary Rust tool that converts between SILK and WAV (and back), so you can:

Why silk?

  silk geniusnut/silk2wav alexyangfox/wechat_silk super1207/a2silk-cli
Language Rust Python Python Python
Single static binary
Encode (back to silk)
Batch processing ✅ native
Magic-byte format detect
Dependencies 6 pure-Rust crates Python + ffmpeg Python Python
Cold-start per file ~10ms ~40-60ms similar similar
License Apache 2.0 MIT

2.5x faster than the Python alternatives, mainly because there’s no per-process Python startup. The actual SILK decode uses the same C SDK underneath.

Quick start

# install
cargo install --git https://github.com/ljh-sh/silk

# decode a WeChat voice message
silk decode voice.silk -o voice.wav

# show metadata
silk info voice.silk

# batch convert a directory
silk batch ./wechat_voices/ -o ./mp3s/ --to wav --pattern "*.silk"

See the Usage page for more.