xmp_exif.js

xmp_exif.js

function findXMPinJPEG(file) {
   var dataView = new DataView(file);

	if (debug) console.log("Got file of length " + file.byteLength);
   if ((dataView.getUint8(0) != 0xFF) || (dataView.getUint8(1) != 0xD8)) {
	   if (debug) console.log("Not a valid JPEG");
	   return false; // not a valid jpeg
   }

	 var offset = 2,
		length = file.byteLength,
		dom = new DOMParser();

	 while (offset < length) {
		if (getStringFromDB(dataView, offset, 4) == "http") {
			var startOffset = offset - 1;
			var sectionLength = dataView.getUint16(offset - 2) - 1;
			var xmpString = getStringFromDB(dataView, startOffset, sectionLength)
			var xmpEndIndex = xmpString.indexOf('xmpmeta>') + 8;
			xmpString = xmpString.substring( xmpString.indexOf( '<x:xmpmeta' ), xmpEndIndex );

			 var indexOfXmp = xmpString.indexOf('x:xmpmeta') + 10
			//Many custom written programs embed xmp/xml without any namespace. Following are some of them.
			//Without these namespaces, XML is thought to be invalid by parsers
			xmpString = xmpString.slice(0, indexOfXmp)
						+ 'xmlns:Iptc4xmpCore="http://iptc.org/std/Iptc4xmpCore/1.0/xmlns/" '
						+ 'xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" '
						+ 'xmlns:tiff="http://ns.adobe.com/tiff/1.0/" '
						+ 'xmlns:plus="http://schemas.android.com/apk/lib/com.google.android.gms.plus" '
						+ 'xmlns:ext="http://www.gettyimages.com/xsltExtension/1.0" '
						+ 'xmlns:exif="http://ns.adobe.com/exif/1.0/" '
						+ 'xmlns:stEvt="http://ns.adobe.com/xap/1.0/sType/ResourceEvent#" '
						+ 'xmlns:stRef="http://ns.adobe.com/xap/1.0/sType/ResourceRef#" '
						+ 'xmlns:crs="http://ns.adobe.com/camera-raw-settings/1.0/" '
						+ 'xmlns:xapGImg="http://ns.adobe.com/xap/1.0/g/img/" '
						+ 'xmlns:Iptc4xmpExt="http://iptc.org/std/Iptc4xmpExt/2008-02-29/" '
						+ xmpString.slice(indexOfXmp)

			 var domDocument = dom.parseFromString( xmpString, 'text/xml' );
			return xml2Object(domDocument);
		} else{
		 offset++;
		}
	}
}