dwv/decoders/rii-mango/decode-jpegloss.js

DICOM Web Viewer.

/**
 * JPEG Lossless decoder worker.
 */
// Do not warn if these variables were not defined before.
/* global importScripts, jpeg */

importScripts('lossless-min.js');

self.addEventListener('message', function (event) {

  // bytes per element
  var bpe = event.data.meta.bitsAllocated / 8;
  // decode DICOM buffer
  var buf = new Uint8Array(event.data.buffer);
  var decoder = new jpeg.lossless.Decoder();
  var decoded = decoder.decode(buf.buffer, 0, buf.buffer.byteLength, bpe);
  // post decoded data
  var res = null;
  if (event.data.meta.bitsAllocated === 8) {
    if (event.data.meta.isSigned) {
      res = new Int8Array(decoded.buffer);
    } else {
      res = new Uint8Array(decoded.buffer);
    }
  } else if (event.data.meta.bitsAllocated === 16) {
    if (event.data.meta.isSigned) {
      res = new Int16Array(decoded.buffer);
    } else {
      res = new Uint16Array(decoded.buffer);
    }
  }
  self.postMessage([res]);

}, false);