js/ml-worker.js

// Web Worker that runs the heavy ML pipelines off the main thread.
// Each call to ml-client spawns a fresh worker; this file is loaded once
// per worker instance and torn down when the worker is terminated.
//
// On iOS / Android, the WebContent process can be killed under memory
// pressure. Putting the model here means a model OOM kills the worker
// (which we already throw away after each op) — the page itself stays
// alive much more often.

import { removeBackground } from './segmentation.js';
import { autoSegment } from './auto-segment.js';

self.onmessage = async (e) => {
  const { type, payload } = e.data || {};

  const onProgress = (info) => {
    try { self.postMessage({ kind: 'progress', payload: info }); } catch (_) {}
  };

  try {
    let result;
    if (type === 'remove-bg') {
      result = await removeBackground(payload.blob, onProgress);
    } else if (type === 'auto-segment') {
      result = await autoSegment(payload.blob, onProgress);
    } else {
      throw new Error(`Unknown task: ${type}`);
    }
    self.postMessage({ kind: 'result', payload: result });
  } catch (err) {
    self.postMessage({
      kind: 'error',
      payload: { message: err && err.message ? err.message : String(err) },
    });
  }
};