codem-isoboxer

// Simulate an ArrayBuffer for demonstration (a minimal ftyp box) // In a real scenario, this buffer would come from XHR, FileReader, etc. const buffer = new ArrayBuffer(16); const view = new DataView(buffer); view.setUint32(0, 16, false); // Box size: 16 bytes view.setUint32(4, 0x66747970, false); // Box type: "ftyp" view.setUint32(8, 0x69736f6d, false); // Major brand: "isom" view.setUint32(12, 0x00000001, false); // Minor version: 1 // In a browser, ISOBoxer would be globally available after including the script: // <script src="iso_boxer.min.js"></script> // For this runnable quickstart demonstration, we'll mock ISOBoxer // In your actual browser code, remove this mock and assume ISOBoxer is global. const ISOBoxer = (() => { const parseBuffer = (arrayBuffer) => { const dv = new DataView(arrayBuffer); const boxes = []; let offset = 0; while (offset < arrayBuffer.byteLength) { const size = dv.getUint32(offset, false); const typeCode = dv.getUint32(offset + 4, false); const type = String.fromCharCode( (typeCode >> 24) & 0xFF, (typeCode >> 16) & 0xFF, (typeCode >> 8) & 0xFF, typeCode & 0xFF ); // In a real parse, more box-specific data would be extracted boxes.push({ _type: type, _size: size, _offset: offset }); offset += size; if (size === 0) break; // Avoid infinite loop for malformed box } return { boxes: boxes, fetch: (boxType) => boxes.find(b => b._type === boxType), fetchAll: (boxType) => boxes.filter(b => b._type === boxType) }; }; return { parseBuffer }; })(); const parsedFile = ISOBoxer.parseBuffer(buffer); console.log('All parsed boxes:', parsedFile.boxes); // Expected: [{ _type: 'ftyp', _size: 16, _offset: 0 }] const ftypBox = parsedFile.fetch('ftyp'); if (ftypBox) { console.log('Fetched ftyp box:', ftypBox); } const allMdatBoxes = parsedFile.fetchAll('mdat'); if (allMdatBoxes.length === 0) { console.log('No mdat boxes found in this example buffer.'); }