const arrayBuffer = new Promise(resolve => {
const fr = new FileReader()
fr.onload = () => resolve(fr.result);
fr.readAsArrayBuffer(movieBlobOrFile);
});
const ebmlJson = new EbmlToJson(arrayBuffer);
console.log(ebmlJson.toString());
console.log(ebmlJson.Segment.Cluster[0].Timecode.value);
console.log(ebmlJson.Segment.Cluster[1].Timecode.value);
ebmlJson.Segment.Cluster[1].Timecode.value = 6600;
const editMovie = ebmlJson.toBlob();
document.getElementsByTagName("video")[0].src = URL.createObjectURL(editMovie);