/* * Javascript EXIF Reader 0.1.6 * Copyright (c) 2008 Jacob Seidelin, jseidelin@nihilogic.dk, http://blog.nihilogic.dk/ * Licensed under the MPL License [http://www.nihilogic.dk/licenses/mpl-license.txt] */ var EXIF = (function() { var debug = false; var ExifTags = { // 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 }; var 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" }; var 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" }; var 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(element, event, handler) { if (element.addEventListener) { element.addEventListener(event, handler, false); } else if (element.attachEvent) { element.attachEvent("on" + event, handler); } } function imageHasData(img) { return !!(img.exifdata); } function getImageData(img, callback) { BinaryAjax(img.src, function(http) { var data = findEXIFinJPEG(http.binaryResponse); img.exifdata = data || {}; if (callback) { callback.call(img) } }); } function findEXIFinJPEG(file) { if (file.getByteAt(0) != 0xFF || file.getByteAt(1) != 0xD8) { return false; // not a valid jpeg } var offset = 2, length = file.getLength(), marker; while (offset < length) { if (file.getByteAt(offset) != 0xFF) { if (debug) console.log("Not a valid marker at offset " + offset + ", found: " + file.getByteAt(offset)); return false; // not a valid marker, something is wrong } marker = file.getByteAt(offset + 1); // we could implement handling for other markers here, // but we're only looking for 0xFFE1 for EXIF data if (marker == 22400) { if (debug) console.log("Found 0xFFE1 marker"); return readEXIFData(file, offset + 4, file.getShortAt(offset + 2, true) - 2); // offset += 2 + file.getShortAt(offset+2, true); } else if (marker == 225) { // 0xE1 = Application-specific 1 (for EXIF) if (debug) console.log("Found 0xFFE1 marker"); return readEXIFData(file, offset + 4, file.getShortAt(offset + 2, true) - 2); } else { offset += 2 + file.getShortAt(offset + 2, true); } } } function readTags(file, tiffStart, dirStart, strings, bigEnd) { var entries = file.getShortAt(dirStart, bigEnd), tags = {}, entryOffset, tag, i; for (i = 0; i < entries; i++) { entryOffset = dirStart + i * 12 + 2; tag = strings[file.getShortAt(entryOffset, bigEnd)]; if (!tag && debug) console.log("Unknown tag: " + file.getShortAt(entryOffset, bigEnd)); tags[tag] = readTagValue(file, entryOffset, tiffStart, dirStart, bigEnd); } return tags; } function readTagValue(file, entryOffset, tiffStart, dirStart, bigEnd) { var type = file.getShortAt(entryOffset + 2, bigEnd), numValues = file.getLongAt(entryOffset + 4, bigEnd), valueOffset = file.getLongAt(entryOffset + 8, bigEnd) + tiffStart, offset, vals, val, n, numerator, denominator; switch (type) { case 1: // byte, 8-bit unsigned int case 7: // undefined, 8-bit byte, value depending on field if (numValues == 1) { return file.getByteAt(entryOffset + 8, bigEnd); } else { offset = numValues > 4 ? valueOffset : (entryOffset + 8); vals = []; for (n = 0; n < numValues; n++) { vals[n] = file.getByteAt(offset + n); } return vals; } case 2: // ascii, 8-bit byte offset = numValues > 4 ? valueOffset : (entryOffset + 8); return file.getStringAt(offset, numValues - 1); case 3: // short, 16 bit int if (numValues == 1) { return file.getShortAt(entryOffset + 8, bigEnd); } else { offset = numValues > 2 ? valueOffset : (entryOffset + 8); vals = []; for (n = 0; n < numValues; n++) { vals[n] = file.getShortAt(offset + 2 * n, bigEnd); } return vals; } case 4: // long, 32 bit int if (numValues == 1) { return file.getLongAt(entryOffset + 8, bigEnd); } else { vals = []; for (var n = 0; n < numValues; n++) { vals[n] = file.getLongAt(valueOffset + 4 * n, bigEnd); } return vals; } case 5: // rational = two long values, first is numerator, second is denominator if (numValues == 1) { numerator = file.getLongAt(valueOffset, bigEnd); denominator = file.getLongAt(valueOffset + 4, bigEnd); val = new Number(numerator / denominator); val.numerator = numerator; val.denominator = denominator; return val; } else { vals = []; for (n = 0; n < numValues; n++) { numerator = file.getLongAt(valueOffset + 8 * n, bigEnd); denominator = file.getLongAt(valueOffset + 4 + 8 * n, bigEnd); vals[n] = new Number(numerator / denominator); vals[n].numerator = numerator; vals[n].denominator = denominator; } return vals; } case 9: // slong, 32 bit signed int if (numValues == 1) { return file.getSLongAt(entryOffset + 8, bigEnd); } else { vals = []; for (n = 0; n < numValues; n++) { vals[n] = file.getSLongAt(valueOffset + 4 * n, bigEnd); } return vals; } case 10: // signed rational, two slongs, first is numerator, second is denominator if (numValues == 1) { return file.getSLongAt(valueOffset, bigEnd) / file.getSLongAt(valueOffset + 4, bigEnd); } else { vals = []; for (n = 0; n < numValues; n++) { vals[n] = file.getSLongAt(valueOffset + 8 * n, bigEnd) / file.getSLongAt(valueOffset + 4 + 8 * n, bigEnd); } return vals; } } } function readEXIFData(file, start) { if (file.getStringAt(start, 4) != "Exif") { if (debug) console.log("Not valid EXIF data! " + file.getStringAt(start, 4)); return false; } var bigEnd, tags, tag, exifData, gpsData, tiffOffset = start + 6; // test for TIFF validity and endianness if (file.getShortAt(tiffOffset) == 0x4949) { bigEnd = false; } else if (file.getShortAt(tiffOffset) == 0x4D4D) { bigEnd = true; } else { if (debug) console.log("Not valid TIFF data! (no 0x4949 or 0x4D4D)"); return false; } if (file.getShortAt(tiffOffset + 2, bigEnd) != 0x002A) { if (debug) console.log("Not valid TIFF data! (no 0x002A)"); return false; } if (file.getLongAt(tiffOffset + 4, bigEnd) != 0x00000008) { if (debug) console.log("Not valid TIFF data! (First offset not 8)", file.getShortAt(tiffOffset + 4, bigEnd)); return false; } tags = readTags(file, tiffOffset, tiffOffset + 8, TiffTags, bigEnd); if (tags.ExifIFDPointer) { exifData = readTags(file, tiffOffset, tiffOffset + tags.ExifIFDPointer, ExifTags, bigEnd); for (tag in exifData) { switch (tag) { 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" : exifData[tag] = StringValues[tag][exifData[tag]]; break; case "ExifVersion" : case "FlashpixVersion" : exifData[tag] = String.fromCharCode(exifData[tag][0], exifData[tag][1], exifData[tag][2], exifData[tag][3]); break; case "ComponentsConfiguration" : exifData[tag] = StringValues.Components[exifData[tag][0]] + StringValues.Components[exifData[tag][1]] + StringValues.Components[exifData[tag][2]] + StringValues.Components[exifData[tag][3]]; break; } tags[tag] = exifData[tag]; } } if (tags.GPSInfoIFDPointer) { gpsData = readTags(file, tiffOffset, tiffOffset + tags.GPSInfoIFDPointer, GPSTags, bigEnd); for (tag in gpsData) { switch (tag) { case "GPSVersionID" : gpsData[tag] = gpsData[tag][0] + "." + gpsData[tag][1] + "." + gpsData[tag][2] + "." + gpsData[tag][3]; break; } tags[tag] = gpsData[tag]; } } return tags; } function getData(img, callback) { if (!img.complete) return false; if (!imageHasData(img)) { getImageData(img, callback); } else { if (callback) { callback.call(img); } } return true; } function getTag(img, tag) { if (!imageHasData(img)) return; return img.exifdata[tag]; } function getAllTags(img) { if (!imageHasData(img)) return {}; var a, data = img.exifdata, tags = {}; for (a in data) { if (data.hasOwnProperty(a)) { tags[a] = data[a]; } } return tags; } function pretty(img) { if (!imageHasData(img)) return ""; var a, data = img.exifdata, strPretty = ""; for (a in data) { if (data.hasOwnProperty(a)) { if (typeof data[a] == "object") { if (data[a] instanceof Number) { strPretty += a + " : " + data[a] + " [" + data[a].numerator + "/" + data[a].denominator + "]\r\n"; } else { strPretty += a + " : [" + data[a].length + " values]\r\n"; } } else { strPretty += a + " : " + data[a] + "\r\n"; } } } return strPretty; } function readFromBinaryFile(file) { return findEXIFinJPEG(file); } return { readFromBinaryFile: readFromBinaryFile, pretty: pretty, getTag: getTag, getAllTags: getAllTags, getData: getData, Tags: ExifTags, TiffTags: TiffTags, GPSTags: GPSTags, StringValues: StringValues }; })();