Events

Every Video is a typed EventEmitter. Events provide process visibility without changing Promise semantics.

video.on('start', (command) => console.log(command));
video.on('stderr', (chunk) => process.stderr.write(chunk));
video.on('progress', ({ frames, fps, time, speed, percent }) => {
  console.log({ frames, fps, time, speed, percent });
});
video.on('end', ({ code, args }) => console.log(code, args));
video.on('error', (error) => console.error(error));

await video.save(output);

Progress model

Property	Type	Meaning
time	number	Encoded media time in seconds
percent	number?	Percentage when source duration is known
frames	number?	Processed video frames
fps	number?	Current processing rate
speed	number?	Multiple of real-time speed

An error listener is optional. Without one, a failed operation rejects its Promise normally instead of triggering an unhandled EventEmitter exception.

Process results

The end event receives the executable, exact arguments, exit code, and retained stdout/stderr. Output is tailed to maxBuffer; exceeding that limit never kills a long conversion.