Web Audio API - record to MP3?

Question

I am asking because I couldn\'t find the answer anywhere. I have successfully implemented RecorderJS in order to record microphone input in JS. However, the recorded file is WAV

Answer 1

There's a library written in pure javascript, called lamejs. To encode mp3s from raw audio. It is much faster than emscripten compile of libmp3lame. https://github.com/zhuker/lamejs

Example usage:

lib = new lamejs();
mp3encoder = new lib.Mp3Encoder(1, 44100, 128); //mono 44.1khz encode to 128kbps
samples = new Int16Array(44100); //one second of silence
var mp3 = mp3encoder.encodeBuffer(samples); //encode mp3