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/*
* Javascript EXIF Reader 0.1.4
* Copyright (c) 2008 Jacob Seidelin, cupboy@gmail.com, http://blog.nihilogic.dk/
* Licensed under the MPL License [http://www.nihilogic.dk/licenses/mpl-license.txt]
*/
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.getAllTags = function(oImg)
{
if (!imageHasData(oImg)) return {};
var oData = oImg.exifdata;
var oAllTags = {};
for (var a in oData) {
if (oData.hasOwnProperty(a)) {
oAllTags[a] = oData[a];
}
}
return oAllTags;
}
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);
})();
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