constructor({ data }) {
    super({ name: 'IHDR', data });
    const dv = new DataView(data);
    defineDataViewProperty(this, 'width', dv, 32, 0);
    defineDataViewProperty(this, 'height', dv, 32, 4);
    defineDataViewProperty(this, 'bitDepth', dv, 8, 8);
    defineDataViewProperty(this, 'colorType', dv, 8, 9);
    defineDataViewProperty(this, 'compression', dv, 8, 10);
    defineDataViewProperty(this, 'filter', dv, 8, 11);
    defineDataViewProperty(this, 'interlace', dv, 8, 12);
  }
The first chunk of a PNG containing the PNG's metadata.