maxim75/exif.html

## exif.html
<!DOCTYPE html>
<html lang="en">
	<head>
		<title>h5</title>
		<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.js"></script>
		<script src="exif.js"></script>
		<style>
			#holder { border: 1px dashed #ccc; width: 100px; height: 100px; margin: 20px auto;}
			#holder.hover { border: 1px dashed #333; }
			#result .property { width: 100px; }
		</style>
	</head>
	<body>
	<section id="wrapper">
	<article>
	  <div id="holder"></div>
	  <p id="status">File API &amp; FileReader API not supported</p>
	</article>
	<table id="result"></table>
	<script>
		function get_exif_data(image_result)
		{
			var data = image_result.replace("data:image/jpeg;base64,", "");
			var decoded_data = decode64(data);

			getLongAt = function(iOffset, bBigEndian) {
						var iByte1 = decoded_data.charCodeAt(iOffset),
							iByte2 = decoded_data.charCodeAt(iOffset + 1),
							iByte3 = decoded_data.charCodeAt(iOffset + 2),
							iByte4 = decoded_data.charCodeAt(iOffset + 3);

						var iLong = bBigEndian ?
							(((((iByte1 << 8) + iByte2) << 8) + iByte3) << 8) + iByte4
							: (((((iByte4 << 8) + iByte3) << 8) + iByte2) << 8) + iByte1;
						if (iLong < 0) iLong += 4294967296;
						return iLong;
					};

			getSLongAt = function(iOffset, bBigEndian) {
				var iULong = getLongAt(iOffset, bBigEndian);
				if (iULong > 2147483647)
					return iULong - 4294967296;
				else
					return iULong;
			};

			var result = findEXIFinJPEG({
				getByteAt: function(idx) { return decoded_data.charCodeAt(idx); },
				getLength: function() { return decoded_data.length; },
				getShortAt: function(iOffset, bBigEndian) {
						var iShort = bBigEndian ?
							(decoded_data.charCodeAt(iOffset) << 8) + decoded_data.charCodeAt(iOffset + 1)
							: (decoded_data.charCodeAt(iOffset + 1) << 8) + decoded_data.charCodeAt(iOffset)
						if (iShort < 0) iShort += 65536;
						return iShort;
					},
				getStringAt: function(a, b) { return decoded_data.substring(a, a+b); },
				getLongAt: getLongAt,
				getSLongAt: getSLongAt
			});
			return result;
		}

		var holder = document.getElementById('holder'),
			state = document.getElementById('status');

		if (typeof window.FileReader === 'undefined') {
		  state.className = 'fail';
		} else {
		  state.className = 'success';
		  state.innerHTML = 'A';
		}

		holder.ondragover = function () { this.className = 'hover'; return false; };
		holder.ondragend = function () { this.className = ''; return false; };
		holder.ondrop = function (e) {
		  this.className = '';
		  e.preventDefault();

		  var file = e.dataTransfer.files[0],
			  reader = new FileReader();
		  reader.onload = function (event) {
			exif_data = get_exif_data(event.target.result);

			for(var idx in exif_data)
			{
				var div = $("<tr />");
				div.append($("<td class=\"property\" />").text(idx));
				div.append($("<td class=\"value\" />").text(JSON.stringify(exif_data[idx])));
				$("#result").append(div);
			}
		  };
		  reader.readAsDataURL(file);

		  return false;
		};

		var keyStr = "ABCDEFGHIJKLMNOP" +
               "QRSTUVWXYZabcdef" +
               "ghijklmnopqrstuv" +
               "wxyz0123456789+/" +
               "=";

		function decode64(input) {
			 var output = "";
			 var chr1, chr2, chr3 = "";
			 var enc1, enc2, enc3, enc4 = "";
			 var i = 0;

			 // remove all characters that are not A-Z, a-z, 0-9, +, /, or =
			 var base64test = /[^A-Za-z0-9\+\/\=]/g;
			 if (base64test.exec(input)) {
				alert("There were invalid base64 characters in the input text.\n" +
					  "Valid base64 characters are A-Z, a-z, 0-9, '+', '/',and '='\n" +
					  "Expect errors in decoding.");
			 }
			 input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

			 do {
				enc1 = keyStr.indexOf(input.charAt(i++));
				enc2 = keyStr.indexOf(input.charAt(i++));
				enc3 = keyStr.indexOf(input.charAt(i++));
				enc4 = keyStr.indexOf(input.charAt(i++));

				chr1 = (enc1 << 2) | (enc2 >> 4);
				chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
				chr3 = ((enc3 & 3) << 6) | enc4;

				output = output + String.fromCharCode(chr1);

				if (enc3 != 64) {
				   output = output + String.fromCharCode(chr2);
				}
				if (enc4 != 64) {
				   output = output + String.fromCharCode(chr3);
				}

				chr1 = chr2 = chr3 = "";
				enc1 = enc2 = enc3 = enc4 = "";

			 } while (i < input.length);

			 return unescape(output);
		  }
	</script>
	</body>
</html>

## exif.js
/*
 * Javascript EXIF Reader 0.1.2
 * Copyright (c) 2008 Jacob Seidelin, cupboy@gmail.com, http://blog.nihilogic.dk/
 * MIT License [http://www.opensource.org/licenses/mit-license.php]
 */


var EXIF = {};

(function() {

var bDebug = false;

EXIF.Tags = {

	// version tags
	0x9000 : "ExifVersion",			// EXIF version
	0xA000 : "FlashpixVersion",		// Flashpix format version

	// colorspace tags
	0xA001 : "ColorSpace",			// Color space information tag

	// image configuration
	0xA002 : "PixelXDimension",		// Valid width of meaningful image
	0xA003 : "PixelYDimension",		// Valid height of meaningful image
	0x9101 : "ComponentsConfiguration",	// Information about channels
	0x9102 : "CompressedBitsPerPixel",	// Compressed bits per pixel

	// user information
	0x927C : "MakerNote",			// Any desired information written by the manufacturer
	0x9286 : "UserComment",			// Comments by user

	// related file
	0xA004 : "RelatedSoundFile",		// Name of related sound file

	// date and time
	0x9003 : "DateTimeOriginal",		// Date and time when the original image was generated
	0x9004 : "DateTimeDigitized",		// Date and time when the image was stored digitally
	0x9290 : "SubsecTime",			// Fractions of seconds for DateTime
	0x9291 : "SubsecTimeOriginal",		// Fractions of seconds for DateTimeOriginal
	0x9292 : "SubsecTimeDigitized",		// Fractions of seconds for DateTimeDigitized

	// picture-taking conditions
	0x829A : "ExposureTime",		// Exposure time (in seconds)
	0x829D : "FNumber",			// F number
	0x8822 : "ExposureProgram",		// Exposure program
	0x8824 : "SpectralSensitivity",		// Spectral sensitivity
	0x8827 : "ISOSpeedRatings",		// ISO speed rating
	0x8828 : "OECF",			// Optoelectric conversion factor
	0x9201 : "ShutterSpeedValue",		// Shutter speed
	0x9202 : "ApertureValue",		// Lens aperture
	0x9203 : "BrightnessValue",		// Value of brightness
	0x9204 : "ExposureBias",		// Exposure bias
	0x9205 : "MaxApertureValue",		// Smallest F number of lens
	0x9206 : "SubjectDistance",		// Distance to subject in meters
	0x9207 : "MeteringMode", 		// Metering mode
	0x9208 : "LightSource",			// Kind of light source
	0x9209 : "Flash",			// Flash status
	0x9214 : "SubjectArea",			// Location and area of main subject
	0x920A : "FocalLength",			// Focal length of the lens in mm
	0xA20B : "FlashEnergy",			// Strobe energy in BCPS
	0xA20C : "SpatialFrequencyResponse",	//
	0xA20E : "FocalPlaneXResolution", 	// Number of pixels in width direction per FocalPlaneResolutionUnit
	0xA20F : "FocalPlaneYResolution", 	// Number of pixels in height direction per FocalPlaneResolutionUnit
	0xA210 : "FocalPlaneResolutionUnit", 	// Unit for measuring FocalPlaneXResolution and FocalPlaneYResolution
	0xA214 : "SubjectLocation",		// Location of subject in image
	0xA215 : "ExposureIndex",		// Exposure index selected on camera
	0xA217 : "SensingMethod", 		// Image sensor type
	0xA300 : "FileSource", 			// Image source (3 == DSC)
	0xA301 : "SceneType", 			// Scene type (1 == directly photographed)
	0xA302 : "CFAPattern",			// Color filter array geometric pattern
	0xA401 : "CustomRendered",		// Special processing
	0xA402 : "ExposureMode",		// Exposure mode
	0xA403 : "WhiteBalance",		// 1 = auto white balance, 2 = manual
	0xA404 : "DigitalZoomRation",		// Digital zoom ratio
	0xA405 : "FocalLengthIn35mmFilm",	// Equivalent foacl length assuming 35mm film camera (in mm)
	0xA406 : "SceneCaptureType",		// Type of scene
	0xA407 : "GainControl",			// Degree of overall image gain adjustment
	0xA408 : "Contrast",			// Direction of contrast processing applied by camera
	0xA409 : "Saturation", 			// Direction of saturation processing applied by camera
	0xA40A : "Sharpness",			// Direction of sharpness processing applied by camera
	0xA40B : "DeviceSettingDescription",	//
	0xA40C : "SubjectDistanceRange",	// Distance to subject

	// other tags
	0xA005 : "InteroperabilityIFDPointer",
	0xA420 : "ImageUniqueID"		// Identifier assigned uniquely to each image
};

EXIF.TiffTags = {
	0x0100 : "ImageWidth",
	0x0101 : "ImageHeight",
	0x8769 : "ExifIFDPointer",
	0x8825 : "GPSInfoIFDPointer",
	0xA005 : "InteroperabilityIFDPointer",
	0x0102 : "BitsPerSample",
	0x0103 : "Compression",
	0x0106 : "PhotometricInterpretation",
	0x0112 : "Orientation",
	0x0115 : "SamplesPerPixel",
	0x011C : "PlanarConfiguration",
	0x0212 : "YCbCrSubSampling",
	0x0213 : "YCbCrPositioning",
	0x011A : "XResolution",
	0x011B : "YResolution",
	0x0128 : "ResolutionUnit",
	0x0111 : "StripOffsets",
	0x0116 : "RowsPerStrip",
	0x0117 : "StripByteCounts",
	0x0201 : "JPEGInterchangeFormat",
	0x0202 : "JPEGInterchangeFormatLength",
	0x012D : "TransferFunction",
	0x013E : "WhitePoint",
	0x013F : "PrimaryChromaticities",
	0x0211 : "YCbCrCoefficients",
	0x0214 : "ReferenceBlackWhite",
	0x0132 : "DateTime",
	0x010E : "ImageDescription",
	0x010F : "Make",
	0x0110 : "Model",
	0x0131 : "Software",
	0x013B : "Artist",
	0x8298 : "Copyright"
}

EXIF.GPSTags = {
	0x0000 : "GPSVersionID",
	0x0001 : "GPSLatitudeRef",
	0x0002 : "GPSLatitude",
	0x0003 : "GPSLongitudeRef",
	0x0004 : "GPSLongitude",
	0x0005 : "GPSAltitudeRef",
	0x0006 : "GPSAltitude",
	0x0007 : "GPSTimeStamp",
	0x0008 : "GPSSatellites",
	0x0009 : "GPSStatus",
	0x000A : "GPSMeasureMode",
	0x000B : "GPSDOP",
	0x000C : "GPSSpeedRef",
	0x000D : "GPSSpeed",
	0x000E : "GPSTrackRef",
	0x000F : "GPSTrack",
	0x0010 : "GPSImgDirectionRef",
	0x0011 : "GPSImgDirection",
	0x0012 : "GPSMapDatum",
	0x0013 : "GPSDestLatitudeRef",
	0x0014 : "GPSDestLatitude",
	0x0015 : "GPSDestLongitudeRef",
	0x0016 : "GPSDestLongitude",
	0x0017 : "GPSDestBearingRef",
	0x0018 : "GPSDestBearing",
	0x0019 : "GPSDestDistanceRef",
	0x001A : "GPSDestDistance",
	0x001B : "GPSProcessingMethod",
	0x001C : "GPSAreaInformation",
	0x001D : "GPSDateStamp",
	0x001E : "GPSDifferential"
}

EXIF.StringValues = {
	ExposureProgram : {
		0 : "Not defined",
		1 : "Manual",
		2 : "Normal program",
		3 : "Aperture priority",
		4 : "Shutter priority",
		5 : "Creative program",
		6 : "Action program",
		7 : "Portrait mode",
		8 : "Landscape mode"
	},
	MeteringMode : {
		0 : "Unknown",
		1 : "Average",
		2 : "CenterWeightedAverage",
		3 : "Spot",
		4 : "MultiSpot",
		5 : "Pattern",
		6 : "Partial",
		255 : "Other"
	},
	LightSource : {
		0 : "Unknown",
		1 : "Daylight",
		2 : "Fluorescent",
		3 : "Tungsten (incandescent light)",
		4 : "Flash",
		9 : "Fine weather",
		10 : "Cloudy weather",
		11 : "Shade",
		12 : "Daylight fluorescent (D 5700 - 7100K)",
		13 : "Day white fluorescent (N 4600 - 5400K)",
		14 : "Cool white fluorescent (W 3900 - 4500K)",
		15 : "White fluorescent (WW 3200 - 3700K)",
		17 : "Standard light A",
		18 : "Standard light B",
		19 : "Standard light C",
		20 : "D55",
		21 : "D65",
		22 : "D75",
		23 : "D50",
		24 : "ISO studio tungsten",
		255 : "Other"
	},
	Flash : {
		0x0000 : "Flash did not fire",
		0x0001 : "Flash fired",
		0x0005 : "Strobe return light not detected",
		0x0007 : "Strobe return light detected",
		0x0009 : "Flash fired, compulsory flash mode",
		0x000D : "Flash fired, compulsory flash mode, return light not detected",
		0x000F : "Flash fired, compulsory flash mode, return light detected",
		0x0010 : "Flash did not fire, compulsory flash mode",
		0x0018 : "Flash did not fire, auto mode",
		0x0019 : "Flash fired, auto mode",
		0x001D : "Flash fired, auto mode, return light not detected",
		0x001F : "Flash fired, auto mode, return light detected",
		0x0020 : "No flash function",
		0x0041 : "Flash fired, red-eye reduction mode",
		0x0045 : "Flash fired, red-eye reduction mode, return light not detected",
		0x0047 : "Flash fired, red-eye reduction mode, return light detected",
		0x0049 : "Flash fired, compulsory flash mode, red-eye reduction mode",
		0x004D : "Flash fired, compulsory flash mode, red-eye reduction mode, return light not detected",
		0x004F : "Flash fired, compulsory flash mode, red-eye reduction mode, return light detected",
		0x0059 : "Flash fired, auto mode, red-eye reduction mode",
		0x005D : "Flash fired, auto mode, return light not detected, red-eye reduction mode",
		0x005F : "Flash fired, auto mode, return light detected, red-eye reduction mode"
	},
	SensingMethod : {
		1 : "Not defined",
		2 : "One-chip color area sensor",
		3 : "Two-chip color area sensor",
		4 : "Three-chip color area sensor",
		5 : "Color sequential area sensor",
		7 : "Trilinear sensor",
		8 : "Color sequential linear sensor"
	},
	SceneCaptureType : {
		0 : "Standard",
		1 : "Landscape",
		2 : "Portrait",
		3 : "Night scene"
	},
	SceneType : {
		1 : "Directly photographed"
	},
	CustomRendered : {
		0 : "Normal process",
		1 : "Custom process"
	},
	WhiteBalance : {
		0 : "Auto white balance",
		1 : "Manual white balance"
	},
	GainControl : {
		0 : "None",
		1 : "Low gain up",
		2 : "High gain up",
		3 : "Low gain down",
		4 : "High gain down"
	},
	Contrast : {
		0 : "Normal",
		1 : "Soft",
		2 : "Hard"
	},
	Saturation : {
		0 : "Normal",
		1 : "Low saturation",
		2 : "High saturation"
	},
	Sharpness : {
		0 : "Normal",
		1 : "Soft",
		2 : "Hard"
	},
	SubjectDistanceRange : {
		0 : "Unknown",
		1 : "Macro",
		2 : "Close view",
		3 : "Distant view"
	},
	FileSource : {
		3 : "DSC"
	},

	Components : {
		0 : "",
		1 : "Y",
		2 : "Cb",
		3 : "Cr",
		4 : "R",
		5 : "G",
		6 : "B"
	}
}

function addEvent(oElement, strEvent, fncHandler)
{
	if (oElement.addEventListener) {
		oElement.addEventListener(strEvent, fncHandler, false);
	} else if (oElement.attachEvent) {
		oElement.attachEvent("on" + strEvent, fncHandler);
	}
}


function imageHasData(oImg)
{
	return !!(oImg.exifdata);
}

function getImageData(oImg, fncCallback)
{
	BinaryAjax(
		oImg.src,
		function(oHTTP) {
			var oEXIF = findEXIFinJPEG(oHTTP.binaryResponse);
			oImg.exifdata = oEXIF || {};
			if (fncCallback) fncCallback();
		}
	)
}

function findEXIFinJPEG(oFile) {
	var aMarkers = [];

	if (oFile.getByteAt(0) != 0xFF || oFile.getByteAt(1) != 0xD8) {
		return false; // not a valid jpeg
	}

	var iOffset = 2;
	var iLength = oFile.getLength();
	while (iOffset < iLength) {
		if (oFile.getByteAt(iOffset) != 0xFF) {
			if (bDebug) console.log("Not a valid marker at offset " + iOffset + ", found: " + oFile.getByteAt(iOffset));
			return false; // not a valid marker, something is wrong
		}

		var iMarker = oFile.getByteAt(iOffset+1);

		// we could implement handling for other markers here,
		// but we're only looking for 0xFFE1 for EXIF data

		if (iMarker == 22400) {
			if (bDebug) console.log("Found 0xFFE1 marker");
			return readEXIFData(oFile, iOffset + 4, oFile.getShortAt(iOffset+2, true)-2);
			iOffset += 2 + oFile.getShortAt(iOffset+2, true);

		} else if (iMarker == 225) {
			// 0xE1 = Application-specific 1 (for EXIF)
			if (bDebug) console.log("Found 0xFFE1 marker");
			return readEXIFData(oFile, iOffset + 4, oFile.getShortAt(iOffset+2, true)-2);

		} else {
			iOffset += 2 + oFile.getShortAt(iOffset+2, true);
		}

	}

}


function readTags(oFile, iTIFFStart, iDirStart, oStrings, bBigEnd)
{
	var iEntries = oFile.getShortAt(iDirStart, bBigEnd);
	var oTags = {};
	for (var i=0;i<iEntries;i++) {
		var iEntryOffset = iDirStart + i*12 + 2;
		var strTag = oStrings[oFile.getShortAt(iEntryOffset, bBigEnd)];
		if (!strTag && bDebug) console.log("Unknown tag: " + oFile.getShortAt(iEntryOffset, bBigEnd));
		oTags[strTag] = readTagValue(oFile, iEntryOffset, iTIFFStart, iDirStart, bBigEnd);
	}
	return oTags;
}


function readTagValue(oFile, iEntryOffset, iTIFFStart, iDirStart, bBigEnd)
{
	var iType = oFile.getShortAt(iEntryOffset+2, bBigEnd);
	var iNumValues = oFile.getLongAt(iEntryOffset+4, bBigEnd);
	var iValueOffset = oFile.getLongAt(iEntryOffset+8, bBigEnd) + iTIFFStart;

	switch (iType) {
		case 1: // byte, 8-bit unsigned int
		case 7: // undefined, 8-bit byte, value depending on field
			if (iNumValues == 1) {
				return oFile.getByteAt(iEntryOffset + 8, bBigEnd);
			} else {
				var iValOffset = iNumValues > 4 ? iValueOffset : (iEntryOffset + 8);
				var aVals = [];
				for (var n=0;n<iNumValues;n++) {
					aVals[n] = oFile.getByteAt(iValOffset + n);
				}
				return aVals;
			}
			break;

		case 2: // ascii, 8-bit byte
			var iStringOffset = iNumValues > 4 ? iValueOffset : (iEntryOffset + 8);
			return oFile.getStringAt(iStringOffset, iNumValues-1);
			break;

		case 3: // short, 16 bit int
			if (iNumValues == 1) {
				return oFile.getShortAt(iEntryOffset + 8, bBigEnd);
			} else {
				var iValOffset = iNumValues > 2 ? iValueOffset : (iEntryOffset + 8);
				var aVals = [];
				for (var n=0;n<iNumValues;n++) {
					aVals[n] = oFile.getShortAt(iValOffset + 2*n, bBigEnd);
				}
				return aVals;
			}
			break;

		case 4: // long, 32 bit int
			if (iNumValues == 1) {
				return oFile.getLongAt(iEntryOffset + 8, bBigEnd);
			} else {
				var aVals = [];
				for (var n=0;n<iNumValues;n++) {
					aVals[n] = oFile.getLongAt(iValueOffset + 4*n, bBigEnd);
				}
				return aVals;
			}
			break;
		case 5:	// rational = two long values, first is numerator, second is denominator
			if (iNumValues == 1) {
				return oFile.getLongAt(iValueOffset, bBigEnd) / oFile.getLongAt(iValueOffset+4, bBigEnd);
			} else {
				var aVals = [];
				for (var n=0;n<iNumValues;n++) {
					aVals[n] = oFile.getLongAt(iValueOffset + 8*n, bBigEnd) / oFile.getLongAt(iValueOffset+4 + 8*n, bBigEnd);
				}
				return aVals;
			}
			break;
		case 9: // slong, 32 bit signed int
			if (iNumValues == 1) {
				return oFile.getSLongAt(iEntryOffset + 8, bBigEnd);
			} else {
				var aVals = [];
				for (var n=0;n<iNumValues;n++) {
					aVals[n] = oFile.getSLongAt(iValueOffset + 4*n, bBigEnd);
				}
				return aVals;
			}
			break;
		case 10: // signed rational, two slongs, first is numerator, second is denominator
			if (iNumValues == 1) {
				return oFile.getSLongAt(iValueOffset, bBigEnd) / oFile.getSLongAt(iValueOffset+4, bBigEnd);
			} else {
				var aVals = [];
				for (var n=0;n<iNumValues;n++) {
					aVals[n] = oFile.getSLongAt(iValueOffset + 8*n, bBigEnd) / oFile.getSLongAt(iValueOffset+4 + 8*n, bBigEnd);
				}
				return aVals;
			}
			break;
	}
}


function readEXIFData(oFile, iStart, iLength)
{
	if (oFile.getStringAt(iStart, 4) != "Exif") {
		if (bDebug) console.log("Not valid EXIF data! " + oFile.getStringAt(iStart, 4));
		return false;
	}

	var bBigEnd;

	var iTIFFOffset = iStart + 6;

	// test for TIFF validity and endianness
	if (oFile.getShortAt(iTIFFOffset) == 0x4949) {
		bBigEnd = false;
	} else if (oFile.getShortAt(iTIFFOffset) == 0x4D4D) {
		bBigEnd = true;
	} else {
		if (bDebug) console.log("Not valid TIFF data! (no 0x4949 or 0x4D4D)");
		return false;
	}

	if (oFile.getShortAt(iTIFFOffset+2, bBigEnd) != 0x002A) {
		if (bDebug) console.log("Not valid TIFF data! (no 0x002A)");
		return false;
	}

	if (oFile.getLongAt(iTIFFOffset+4, bBigEnd) != 0x00000008) {
		if (bDebug) console.log("Not valid TIFF data! (First offset not 8)", oFile.getShortAt(iTIFFOffset+4, bBigEnd));
		return false;
	}

	var oTags = readTags(oFile, iTIFFOffset, iTIFFOffset+8, EXIF.TiffTags, bBigEnd);

	if (oTags.ExifIFDPointer) {
		var oEXIFTags = readTags(oFile, iTIFFOffset, iTIFFOffset + oTags.ExifIFDPointer, EXIF.Tags, bBigEnd);
		for (var strTag in oEXIFTags) {
			switch (strTag) {
				case "LightSource" :
				case "Flash" :
				case "MeteringMode" :
				case "ExposureProgram" :
				case "SensingMethod" :
				case "SceneCaptureType" :
				case "SceneType" :
				case "CustomRendered" :
				case "WhiteBalance" :
				case "GainControl" :
				case "Contrast" :
				case "Saturation" :
				case "Sharpness" :
				case "SubjectDistanceRange" :
				case "FileSource" :
					oEXIFTags[strTag] = EXIF.StringValues[strTag][oEXIFTags[strTag]];
					break;

				case "ExifVersion" :
				case "FlashpixVersion" :
					oEXIFTags[strTag] = String.fromCharCode(oEXIFTags[strTag][0], oEXIFTags[strTag][1], oEXIFTags[strTag][2], oEXIFTags[strTag][3]);
					break;

				case "ComponentsConfiguration" :
					oEXIFTags[strTag] =
						EXIF.StringValues.Components[oEXIFTags[strTag][0]]
						+ EXIF.StringValues.Components[oEXIFTags[strTag][1]]
						+ EXIF.StringValues.Components[oEXIFTags[strTag][2]]
						+ EXIF.StringValues.Components[oEXIFTags[strTag][3]];
					break;
			}
			oTags[strTag] = oEXIFTags[strTag];
		}
	}

	if (oTags.GPSInfoIFDPointer) {
		var oGPSTags = readTags(oFile, iTIFFOffset, iTIFFOffset + oTags.GPSInfoIFDPointer, EXIF.GPSTags, bBigEnd);
		for (var strTag in oGPSTags) {
			switch (strTag) {
				case "GPSVersionID" :
					oGPSTags[strTag] = oGPSTags[strTag][0]
						+ "." + oGPSTags[strTag][1]
						+ "." + oGPSTags[strTag][2]
						+ "." + oGPSTags[strTag][3];
					break;
			}
			oTags[strTag] = oGPSTags[strTag];
		}
	}

	return oTags;
}


EXIF.getData = function(oImg, fncCallback)
{
	if (!oImg.complete) return false;
	if (!imageHasData(oImg)) {
		getImageData(oImg, fncCallback);
	} else {
		if (fncCallback) fncCallback();
	}
	return true;
}

EXIF.getTag = function(oImg, strTag)
{
	if (!imageHasData(oImg)) return;
	return oImg.exifdata[strTag];
}

EXIF.pretty = function(oImg)
{
	if (!imageHasData(oImg)) return "";
	var oData = oImg.exifdata;
	var strPretty = "";
	for (var a in oData) {
		if (oData.hasOwnProperty(a)) {
			if (typeof oData[a] == "object") {
				strPretty += a + " : [" + oData[a].length + " values]\r\n";
			} else {
				strPretty += a + " : " + oData[a] + "\r\n";
			}
		}
	}
	return strPretty;
}

EXIF.readFromBinaryFile = function(oFile) {
	return findEXIFinJPEG(oFile);
}

function loadAllImages()
{
	var aImages = document.getElementsByTagName("img");
	for (var i=0;i<aImages.length;i++) {
		if (aImages[i].getAttribute("exif") == "true") {
			if (!aImages[i].complete) {
				addEvent(aImages[i], "load",
					function() {
						EXIF.getData(this);
					}
				);
			} else {
				EXIF.getData(aImages[i]);
			}
		}
	}
}

addEvent(window, "load", loadAllImages);
window.findEXIFinJPEG = findEXIFinJPEG;

})();
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<title>h5</title>
	<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.js"></script>
	<script src="exif.js"></script>
	<style>
	#holder { border: 1px dashed #ccc; width: 100px; height: 100px; margin: 20px auto;}
	#holder.hover { border: 1px dashed #333; }
	#result .property { width: 100px; }
	</style>
	</head>
	<body>
	<section id="wrapper">
	<article>
	<div id="holder"></div>
	<p id="status">File API & FileReader API not supported</p>
	</article>
	<table id="result"></table>
	<script>
	function get_exif_data(image_result)
	{
	var data = image_result.replace("data:image/jpeg;base64,", "");
	var decoded_data = decode64(data);

	getLongAt = function(iOffset, bBigEndian) {
	var iByte1 = decoded_data.charCodeAt(iOffset),
	iByte2 = decoded_data.charCodeAt(iOffset + 1),
	iByte3 = decoded_data.charCodeAt(iOffset + 2),
	iByte4 = decoded_data.charCodeAt(iOffset + 3);

	var iLong = bBigEndian ?
	(((((iByte1 << 8) + iByte2) << 8) + iByte3) << 8) + iByte4
	: (((((iByte4 << 8) + iByte3) << 8) + iByte2) << 8) + iByte1;
	if (iLong < 0) iLong += 4294967296;
	return iLong;
	};

	getSLongAt = function(iOffset, bBigEndian) {
	var iULong = getLongAt(iOffset, bBigEndian);
	if (iULong > 2147483647)
	return iULong - 4294967296;
	else
	return iULong;
	};

	var result = findEXIFinJPEG({
	getByteAt: function(idx) { return decoded_data.charCodeAt(idx); },
	getLength: function() { return decoded_data.length; },
	getShortAt: function(iOffset, bBigEndian) {
	var iShort = bBigEndian ?
	(decoded_data.charCodeAt(iOffset) << 8) + decoded_data.charCodeAt(iOffset + 1)
	: (decoded_data.charCodeAt(iOffset + 1) << 8) + decoded_data.charCodeAt(iOffset)
	if (iShort < 0) iShort += 65536;
	return iShort;
	},
	getStringAt: function(a, b) { return decoded_data.substring(a, a+b); },
	getLongAt: getLongAt,
	getSLongAt: getSLongAt
	});
	return result;
	}

	var holder = document.getElementById('holder'),
	state = document.getElementById('status');

	if (typeof window.FileReader === 'undefined') {
	state.className = 'fail';
	} else {
	state.className = 'success';
	state.innerHTML = 'A';
	}

	holder.ondragover = function () { this.className = 'hover'; return false; };
	holder.ondragend = function () { this.className = ''; return false; };
	holder.ondrop = function (e) {
	this.className = '';
	e.preventDefault();

	var file = e.dataTransfer.files[0],
	reader = new FileReader();
	reader.onload = function (event) {
	exif_data = get_exif_data(event.target.result);

	for(var idx in exif_data)
	{
	var div = $("<tr />");
	div.append($("<td class=\"property\" />").text(idx));
	div.append($("<td class=\"value\" />").text(JSON.stringify(exif_data[idx])));
	$("#result").append(div);
	}
	};
	reader.readAsDataURL(file);

	return false;
	};

	var keyStr = "ABCDEFGHIJKLMNOP" +
	"QRSTUVWXYZabcdef" +
	"ghijklmnopqrstuv" +
	"wxyz0123456789+/" +
	"=";

	function decode64(input) {
	var output = "";
	var chr1, chr2, chr3 = "";
	var enc1, enc2, enc3, enc4 = "";
	var i = 0;

	// remove all characters that are not A-Z, a-z, 0-9, +, /, or =
	var base64test = /[^A-Za-z0-9\+\/\=]/g;
	if (base64test.exec(input)) {
	alert("There were invalid base64 characters in the input text.\n" +
	"Valid base64 characters are A-Z, a-z, 0-9, '+', '/',and '='\n" +
	"Expect errors in decoding.");
	}
	input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

	do {
	enc1 = keyStr.indexOf(input.charAt(i++));
	enc2 = keyStr.indexOf(input.charAt(i++));
	enc3 = keyStr.indexOf(input.charAt(i++));
	enc4 = keyStr.indexOf(input.charAt(i++));

	chr1 = (enc1 << 2) \| (enc2 >> 4);
	chr2 = ((enc2 & 15) << 4) \| (enc3 >> 2);
	chr3 = ((enc3 & 3) << 6) \| enc4;

	output = output + String.fromCharCode(chr1);

	if (enc3 != 64) {
	output = output + String.fromCharCode(chr2);
	}
	if (enc4 != 64) {
	output = output + String.fromCharCode(chr3);
	}

	chr1 = chr2 = chr3 = "";
	enc1 = enc2 = enc3 = enc4 = "";

	} while (i < input.length);

	return unescape(output);
	}
	</script>
	</body>
	</html>
	/*
	* Javascript EXIF Reader 0.1.2
	* Copyright (c) 2008 Jacob Seidelin, cupboy@gmail.com, http://blog.nihilogic.dk/
	* MIT License [http://www.opensource.org/licenses/mit-license.php]
	*/


	var EXIF = {};

	(function() {

	var bDebug = false;

	EXIF.Tags = {

	// version tags
	0x9000 : "ExifVersion", // EXIF version
	0xA000 : "FlashpixVersion", // Flashpix format version

	// colorspace tags
	0xA001 : "ColorSpace", // Color space information tag

	// image configuration
	0xA002 : "PixelXDimension", // Valid width of meaningful image
	0xA003 : "PixelYDimension", // Valid height of meaningful image
	0x9101 : "ComponentsConfiguration", // Information about channels
	0x9102 : "CompressedBitsPerPixel", // Compressed bits per pixel

	// user information
	0x927C : "MakerNote", // Any desired information written by the manufacturer
	0x9286 : "UserComment", // Comments by user

	// related file
	0xA004 : "RelatedSoundFile", // Name of related sound file

	// date and time
	0x9003 : "DateTimeOriginal", // Date and time when the original image was generated
	0x9004 : "DateTimeDigitized", // Date and time when the image was stored digitally
	0x9290 : "SubsecTime", // Fractions of seconds for DateTime
	0x9291 : "SubsecTimeOriginal", // Fractions of seconds for DateTimeOriginal
	0x9292 : "SubsecTimeDigitized", // Fractions of seconds for DateTimeDigitized

	// picture-taking conditions
	0x829A : "ExposureTime", // Exposure time (in seconds)
	0x829D : "FNumber", // F number
	0x8822 : "ExposureProgram", // Exposure program
	0x8824 : "SpectralSensitivity", // Spectral sensitivity
	0x8827 : "ISOSpeedRatings", // ISO speed rating
	0x8828 : "OECF", // Optoelectric conversion factor
	0x9201 : "ShutterSpeedValue", // Shutter speed
	0x9202 : "ApertureValue", // Lens aperture
	0x9203 : "BrightnessValue", // Value of brightness
	0x9204 : "ExposureBias", // Exposure bias
	0x9205 : "MaxApertureValue", // Smallest F number of lens
	0x9206 : "SubjectDistance", // Distance to subject in meters
	0x9207 : "MeteringMode", // Metering mode
	0x9208 : "LightSource", // Kind of light source
	0x9209 : "Flash", // Flash status
	0x9214 : "SubjectArea", // Location and area of main subject
	0x920A : "FocalLength", // Focal length of the lens in mm
	0xA20B : "FlashEnergy", // Strobe energy in BCPS
	0xA20C : "SpatialFrequencyResponse", //
	0xA20E : "FocalPlaneXResolution", // Number of pixels in width direction per FocalPlaneResolutionUnit
	0xA20F : "FocalPlaneYResolution", // Number of pixels in height direction per FocalPlaneResolutionUnit
	0xA210 : "FocalPlaneResolutionUnit", // Unit for measuring FocalPlaneXResolution and FocalPlaneYResolution
	0xA214 : "SubjectLocation", // Location of subject in image
	0xA215 : "ExposureIndex", // Exposure index selected on camera
	0xA217 : "SensingMethod", // Image sensor type
	0xA300 : "FileSource", // Image source (3 == DSC)
	0xA301 : "SceneType", // Scene type (1 == directly photographed)
	0xA302 : "CFAPattern", // Color filter array geometric pattern
	0xA401 : "CustomRendered", // Special processing
	0xA402 : "ExposureMode", // Exposure mode
	0xA403 : "WhiteBalance", // 1 = auto white balance, 2 = manual
	0xA404 : "DigitalZoomRation", // Digital zoom ratio
	0xA405 : "FocalLengthIn35mmFilm", // Equivalent foacl length assuming 35mm film camera (in mm)
	0xA406 : "SceneCaptureType", // Type of scene
	0xA407 : "GainControl", // Degree of overall image gain adjustment
	0xA408 : "Contrast", // Direction of contrast processing applied by camera
	0xA409 : "Saturation", // Direction of saturation processing applied by camera
	0xA40A : "Sharpness", // Direction of sharpness processing applied by camera
	0xA40B : "DeviceSettingDescription", //
	0xA40C : "SubjectDistanceRange", // Distance to subject

	// other tags
	0xA005 : "InteroperabilityIFDPointer",
	0xA420 : "ImageUniqueID" // Identifier assigned uniquely to each image
	};

	EXIF.TiffTags = {
	0x0100 : "ImageWidth",
	0x0101 : "ImageHeight",
	0x8769 : "ExifIFDPointer",
	0x8825 : "GPSInfoIFDPointer",
	0xA005 : "InteroperabilityIFDPointer",
	0x0102 : "BitsPerSample",
	0x0103 : "Compression",
	0x0106 : "PhotometricInterpretation",
	0x0112 : "Orientation",
	0x0115 : "SamplesPerPixel",
	0x011C : "PlanarConfiguration",
	0x0212 : "YCbCrSubSampling",
	0x0213 : "YCbCrPositioning",
	0x011A : "XResolution",
	0x011B : "YResolution",
	0x0128 : "ResolutionUnit",
	0x0111 : "StripOffsets",
	0x0116 : "RowsPerStrip",
	0x0117 : "StripByteCounts",
	0x0201 : "JPEGInterchangeFormat",
	0x0202 : "JPEGInterchangeFormatLength",
	0x012D : "TransferFunction",
	0x013E : "WhitePoint",
	0x013F : "PrimaryChromaticities",
	0x0211 : "YCbCrCoefficients",
	0x0214 : "ReferenceBlackWhite",
	0x0132 : "DateTime",
	0x010E : "ImageDescription",
	0x010F : "Make",
	0x0110 : "Model",
	0x0131 : "Software",
	0x013B : "Artist",
	0x8298 : "Copyright"
	}

	EXIF.GPSTags = {
	0x0000 : "GPSVersionID",
	0x0001 : "GPSLatitudeRef",
	0x0002 : "GPSLatitude",
	0x0003 : "GPSLongitudeRef",
	0x0004 : "GPSLongitude",
	0x0005 : "GPSAltitudeRef",
	0x0006 : "GPSAltitude",
	0x0007 : "GPSTimeStamp",
	0x0008 : "GPSSatellites",
	0x0009 : "GPSStatus",
	0x000A : "GPSMeasureMode",
	0x000B : "GPSDOP",
	0x000C : "GPSSpeedRef",
	0x000D : "GPSSpeed",
	0x000E : "GPSTrackRef",
	0x000F : "GPSTrack",
	0x0010 : "GPSImgDirectionRef",
	0x0011 : "GPSImgDirection",
	0x0012 : "GPSMapDatum",
	0x0013 : "GPSDestLatitudeRef",
	0x0014 : "GPSDestLatitude",
	0x0015 : "GPSDestLongitudeRef",
	0x0016 : "GPSDestLongitude",
	0x0017 : "GPSDestBearingRef",
	0x0018 : "GPSDestBearing",
	0x0019 : "GPSDestDistanceRef",
	0x001A : "GPSDestDistance",
	0x001B : "GPSProcessingMethod",
	0x001C : "GPSAreaInformation",
	0x001D : "GPSDateStamp",
	0x001E : "GPSDifferential"
	}

	EXIF.StringValues = {
	ExposureProgram : {
	0 : "Not defined",
	1 : "Manual",
	2 : "Normal program",
	3 : "Aperture priority",
	4 : "Shutter priority",
	5 : "Creative program",
	6 : "Action program",
	7 : "Portrait mode",
	8 : "Landscape mode"
	},
	MeteringMode : {
	0 : "Unknown",
	1 : "Average",
	2 : "CenterWeightedAverage",
	3 : "Spot",
	4 : "MultiSpot",
	5 : "Pattern",
	6 : "Partial",
	255 : "Other"
	},
	LightSource : {
	0 : "Unknown",
	1 : "Daylight",
	2 : "Fluorescent",
	3 : "Tungsten (incandescent light)",
	4 : "Flash",
	9 : "Fine weather",
	10 : "Cloudy weather",
	11 : "Shade",
	12 : "Daylight fluorescent (D 5700 - 7100K)",
	13 : "Day white fluorescent (N 4600 - 5400K)",
	14 : "Cool white fluorescent (W 3900 - 4500K)",
	15 : "White fluorescent (WW 3200 - 3700K)",
	17 : "Standard light A",
	18 : "Standard light B",
	19 : "Standard light C",
	20 : "D55",
	21 : "D65",
	22 : "D75",
	23 : "D50",
	24 : "ISO studio tungsten",
	255 : "Other"
	},
	Flash : {
	0x0000 : "Flash did not fire",
	0x0001 : "Flash fired",
	0x0005 : "Strobe return light not detected",
	0x0007 : "Strobe return light detected",
	0x0009 : "Flash fired, compulsory flash mode",
	0x000D : "Flash fired, compulsory flash mode, return light not detected",
	0x000F : "Flash fired, compulsory flash mode, return light detected",
	0x0010 : "Flash did not fire, compulsory flash mode",
	0x0018 : "Flash did not fire, auto mode",
	0x0019 : "Flash fired, auto mode",
	0x001D : "Flash fired, auto mode, return light not detected",
	0x001F : "Flash fired, auto mode, return light detected",
	0x0020 : "No flash function",
	0x0041 : "Flash fired, red-eye reduction mode",
	0x0045 : "Flash fired, red-eye reduction mode, return light not detected",
	0x0047 : "Flash fired, red-eye reduction mode, return light detected",
	0x0049 : "Flash fired, compulsory flash mode, red-eye reduction mode",
	0x004D : "Flash fired, compulsory flash mode, red-eye reduction mode, return light not detected",
	0x004F : "Flash fired, compulsory flash mode, red-eye reduction mode, return light detected",
	0x0059 : "Flash fired, auto mode, red-eye reduction mode",
	0x005D : "Flash fired, auto mode, return light not detected, red-eye reduction mode",
	0x005F : "Flash fired, auto mode, return light detected, red-eye reduction mode"
	},
	SensingMethod : {
	1 : "Not defined",
	2 : "One-chip color area sensor",
	3 : "Two-chip color area sensor",
	4 : "Three-chip color area sensor",
	5 : "Color sequential area sensor",
	7 : "Trilinear sensor",
	8 : "Color sequential linear sensor"
	},
	SceneCaptureType : {
	0 : "Standard",
	1 : "Landscape",
	2 : "Portrait",
	3 : "Night scene"
	},
	SceneType : {
	1 : "Directly photographed"
	},
	CustomRendered : {
	0 : "Normal process",
	1 : "Custom process"
	},
	WhiteBalance : {
	0 : "Auto white balance",
	1 : "Manual white balance"
	},
	GainControl : {
	0 : "None",
	1 : "Low gain up",
	2 : "High gain up",
	3 : "Low gain down",
	4 : "High gain down"
	},
	Contrast : {
	0 : "Normal",
	1 : "Soft",
	2 : "Hard"
	},
	Saturation : {
	0 : "Normal",
	1 : "Low saturation",
	2 : "High saturation"
	},
	Sharpness : {
	0 : "Normal",
	1 : "Soft",
	2 : "Hard"
	},
	SubjectDistanceRange : {
	0 : "Unknown",
	1 : "Macro",
	2 : "Close view",
	3 : "Distant view"
	},
	FileSource : {
	3 : "DSC"
	},

	Components : {
	0 : "",
	1 : "Y",
	2 : "Cb",
	3 : "Cr",
	4 : "R",
	5 : "G",
	6 : "B"
	}
	}

	function addEvent(oElement, strEvent, fncHandler)
	{
	if (oElement.addEventListener) {
	oElement.addEventListener(strEvent, fncHandler, false);
	} else if (oElement.attachEvent) {
	oElement.attachEvent("on" + strEvent, fncHandler);
	}
	}


	function imageHasData(oImg)
	{
	return !!(oImg.exifdata);
	}

	function getImageData(oImg, fncCallback)
	{
	BinaryAjax(
	oImg.src,
	function(oHTTP) {
	var oEXIF = findEXIFinJPEG(oHTTP.binaryResponse);
	oImg.exifdata = oEXIF \|\| {};
	if (fncCallback) fncCallback();
	}
	)
	}

	function findEXIFinJPEG(oFile) {
	var aMarkers = [];

	if (oFile.getByteAt(0) != 0xFF \|\| oFile.getByteAt(1) != 0xD8) {
	return false; // not a valid jpeg
	}

	var iOffset = 2;
	var iLength = oFile.getLength();
	while (iOffset < iLength) {
	if (oFile.getByteAt(iOffset) != 0xFF) {
	if (bDebug) console.log("Not a valid marker at offset " + iOffset + ", found: " + oFile.getByteAt(iOffset));
	return false; // not a valid marker, something is wrong
	}

	var iMarker = oFile.getByteAt(iOffset+1);

	// we could implement handling for other markers here,
	// but we're only looking for 0xFFE1 for EXIF data

	if (iMarker == 22400) {
	if (bDebug) console.log("Found 0xFFE1 marker");
	return readEXIFData(oFile, iOffset + 4, oFile.getShortAt(iOffset+2, true)-2);
	iOffset += 2 + oFile.getShortAt(iOffset+2, true);

	} else if (iMarker == 225) {
	// 0xE1 = Application-specific 1 (for EXIF)
	if (bDebug) console.log("Found 0xFFE1 marker");
	return readEXIFData(oFile, iOffset + 4, oFile.getShortAt(iOffset+2, true)-2);

	} else {
	iOffset += 2 + oFile.getShortAt(iOffset+2, true);
	}

	}

	}


	function readTags(oFile, iTIFFStart, iDirStart, oStrings, bBigEnd)
	{
	var iEntries = oFile.getShortAt(iDirStart, bBigEnd);
	var oTags = {};
	for (var i=0;i<iEntries;i++) {
	var iEntryOffset = iDirStart + i*12 + 2;
	var strTag = oStrings[oFile.getShortAt(iEntryOffset, bBigEnd)];
	if (!strTag && bDebug) console.log("Unknown tag: " + oFile.getShortAt(iEntryOffset, bBigEnd));
	oTags[strTag] = readTagValue(oFile, iEntryOffset, iTIFFStart, iDirStart, bBigEnd);
	}
	return oTags;
	}


	function readTagValue(oFile, iEntryOffset, iTIFFStart, iDirStart, bBigEnd)
	{
	var iType = oFile.getShortAt(iEntryOffset+2, bBigEnd);
	var iNumValues = oFile.getLongAt(iEntryOffset+4, bBigEnd);
	var iValueOffset = oFile.getLongAt(iEntryOffset+8, bBigEnd) + iTIFFStart;

	switch (iType) {
	case 1: // byte, 8-bit unsigned int
	case 7: // undefined, 8-bit byte, value depending on field
	if (iNumValues == 1) {
	return oFile.getByteAt(iEntryOffset + 8, bBigEnd);
	} else {
	var iValOffset = iNumValues > 4 ? iValueOffset : (iEntryOffset + 8);
	var aVals = [];
	for (var n=0;n<iNumValues;n++) {
	aVals[n] = oFile.getByteAt(iValOffset + n);
	}
	return aVals;
	}
	break;

	case 2: // ascii, 8-bit byte
	var iStringOffset = iNumValues > 4 ? iValueOffset : (iEntryOffset + 8);
	return oFile.getStringAt(iStringOffset, iNumValues-1);
	break;

	case 3: // short, 16 bit int
	if (iNumValues == 1) {
	return oFile.getShortAt(iEntryOffset + 8, bBigEnd);
	} else {
	var iValOffset = iNumValues > 2 ? iValueOffset : (iEntryOffset + 8);
	var aVals = [];
	for (var n=0;n<iNumValues;n++) {
	aVals[n] = oFile.getShortAt(iValOffset + 2*n, bBigEnd);
	}
	return aVals;
	}
	break;

	case 4: // long, 32 bit int
	if (iNumValues == 1) {
	return oFile.getLongAt(iEntryOffset + 8, bBigEnd);
	} else {
	var aVals = [];
	for (var n=0;n<iNumValues;n++) {
	aVals[n] = oFile.getLongAt(iValueOffset + 4*n, bBigEnd);
	}
	return aVals;
	}
	break;
	case 5: // rational = two long values, first is numerator, second is denominator
	if (iNumValues == 1) {
	return oFile.getLongAt(iValueOffset, bBigEnd) / oFile.getLongAt(iValueOffset+4, bBigEnd);
	} else {
	var aVals = [];
	for (var n=0;n<iNumValues;n++) {
	aVals[n] = oFile.getLongAt(iValueOffset + 8n, bBigEnd) / oFile.getLongAt(iValueOffset+4 + 8n, bBigEnd);
	}
	return aVals;
	}
	break;
	case 9: // slong, 32 bit signed int
	if (iNumValues == 1) {
	return oFile.getSLongAt(iEntryOffset + 8, bBigEnd);
	} else {
	var aVals = [];
	for (var n=0;n<iNumValues;n++) {
	aVals[n] = oFile.getSLongAt(iValueOffset + 4*n, bBigEnd);
	}
	return aVals;
	}
	break;
	case 10: // signed rational, two slongs, first is numerator, second is denominator
	if (iNumValues == 1) {
	return oFile.getSLongAt(iValueOffset, bBigEnd) / oFile.getSLongAt(iValueOffset+4, bBigEnd);
	} else {
	var aVals = [];
	for (var n=0;n<iNumValues;n++) {
	aVals[n] = oFile.getSLongAt(iValueOffset + 8n, bBigEnd) / oFile.getSLongAt(iValueOffset+4 + 8n, bBigEnd);
	}
	return aVals;
	}
	break;
	}
	}


	function readEXIFData(oFile, iStart, iLength)
	{
	if (oFile.getStringAt(iStart, 4) != "Exif") {
	if (bDebug) console.log("Not valid EXIF data! " + oFile.getStringAt(iStart, 4));
	return false;
	}

	var bBigEnd;

	var iTIFFOffset = iStart + 6;

	// test for TIFF validity and endianness
	if (oFile.getShortAt(iTIFFOffset) == 0x4949) {
	bBigEnd = false;
	} else if (oFile.getShortAt(iTIFFOffset) == 0x4D4D) {
	bBigEnd = true;
	} else {
	if (bDebug) console.log("Not valid TIFF data! (no 0x4949 or 0x4D4D)");
	return false;
	}

	if (oFile.getShortAt(iTIFFOffset+2, bBigEnd) != 0x002A) {
	if (bDebug) console.log("Not valid TIFF data! (no 0x002A)");
	return false;
	}

	if (oFile.getLongAt(iTIFFOffset+4, bBigEnd) != 0x00000008) {
	if (bDebug) console.log("Not valid TIFF data! (First offset not 8)", oFile.getShortAt(iTIFFOffset+4, bBigEnd));
	return false;
	}

	var oTags = readTags(oFile, iTIFFOffset, iTIFFOffset+8, EXIF.TiffTags, bBigEnd);

	if (oTags.ExifIFDPointer) {
	var oEXIFTags = readTags(oFile, iTIFFOffset, iTIFFOffset + oTags.ExifIFDPointer, EXIF.Tags, bBigEnd);
	for (var strTag in oEXIFTags) {
	switch (strTag) {
	case "LightSource" :
	case "Flash" :
	case "MeteringMode" :
	case "ExposureProgram" :
	case "SensingMethod" :
	case "SceneCaptureType" :
	case "SceneType" :
	case "CustomRendered" :
	case "WhiteBalance" :
	case "GainControl" :
	case "Contrast" :
	case "Saturation" :
	case "Sharpness" :
	case "SubjectDistanceRange" :
	case "FileSource" :
	oEXIFTags[strTag] = EXIF.StringValues[strTag][oEXIFTags[strTag]];
	break;

	case "ExifVersion" :
	case "FlashpixVersion" :
	oEXIFTags[strTag] = String.fromCharCode(oEXIFTags[strTag][0], oEXIFTags[strTag][1], oEXIFTags[strTag][2], oEXIFTags[strTag][3]);
	break;

	case "ComponentsConfiguration" :
	oEXIFTags[strTag] =
	EXIF.StringValues.Components[oEXIFTags[strTag][0]]
	+ EXIF.StringValues.Components[oEXIFTags[strTag][1]]
	+ EXIF.StringValues.Components[oEXIFTags[strTag][2]]
	+ EXIF.StringValues.Components[oEXIFTags[strTag][3]];
	break;
	}
	oTags[strTag] = oEXIFTags[strTag];
	}
	}

	if (oTags.GPSInfoIFDPointer) {
	var oGPSTags = readTags(oFile, iTIFFOffset, iTIFFOffset + oTags.GPSInfoIFDPointer, EXIF.GPSTags, bBigEnd);
	for (var strTag in oGPSTags) {
	switch (strTag) {
	case "GPSVersionID" :
	oGPSTags[strTag] = oGPSTags[strTag][0]
	+ "." + oGPSTags[strTag][1]
	+ "." + oGPSTags[strTag][2]
	+ "." + oGPSTags[strTag][3];
	break;
	}
	oTags[strTag] = oGPSTags[strTag];
	}
	}

	return oTags;
	}


	EXIF.getData = function(oImg, fncCallback)
	{
	if (!oImg.complete) return false;
	if (!imageHasData(oImg)) {
	getImageData(oImg, fncCallback);
	} else {
	if (fncCallback) fncCallback();
	}
	return true;
	}

	EXIF.getTag = function(oImg, strTag)
	{
	if (!imageHasData(oImg)) return;
	return oImg.exifdata[strTag];
	}

	EXIF.pretty = function(oImg)
	{
	if (!imageHasData(oImg)) return "";
	var oData = oImg.exifdata;
	var strPretty = "";
	for (var a in oData) {
	if (oData.hasOwnProperty(a)) {
	if (typeof oData[a] == "object") {
	strPretty += a + " : [" + oData[a].length + " values]\r\n";
	} else {
	strPretty += a + " : " + oData[a] + "\r\n";
	}
	}
	}
	return strPretty;
	}

	EXIF.readFromBinaryFile = function(oFile) {
	return findEXIFinJPEG(oFile);
	}

	function loadAllImages()
	{
	var aImages = document.getElementsByTagName("img");
	for (var i=0;i<aImages.length;i++) {
	if (aImages[i].getAttribute("exif") == "true") {
	if (!aImages[i].complete) {
	addEvent(aImages[i], "load",
	function() {
	EXIF.getData(this);
	}
	);
	} else {
	EXIF.getData(aImages[i]);
	}
	}
	}
	}

	addEvent(window, "load", loadAllImages);
	window.findEXIFinJPEG = findEXIFinJPEG;

	})();