1/* 2 * Javascript EXIF Reader 0.1.2 3 * Copyright (c) 2008 Jacob Seidelin, cupboy@gmail.com, http://blog.nihilogic.dk/ 4 * MIT License [http://www.opensource.org/licenses/mit-license.php] 5 */ 6 7 8var EXIF = {}; 9 10(function() { 11 12var bDebug = false; 13 14EXIF.Tags = { 15 16 // version tags 17 0x9000 : "ExifVersion", // EXIF version 18 0xA000 : "FlashpixVersion", // Flashpix format version 19 20 // colorspace tags 21 0xA001 : "ColorSpace", // Color space information tag 22 23 // image configuration 24 0xA002 : "PixelXDimension", // Valid width of meaningful image 25 0xA003 : "PixelYDimension", // Valid height of meaningful image 26 0x9101 : "ComponentsConfiguration", // Information about channels 27 0x9102 : "CompressedBitsPerPixel", // Compressed bits per pixel 28 29 // user information 30 0x927C : "MakerNote", // Any desired information written by the manufacturer 31 0x9286 : "UserComment", // Comments by user 32 33 // related file 34 0xA004 : "RelatedSoundFile", // Name of related sound file 35 36 // date and time 37 0x9003 : "DateTimeOriginal", // Date and time when the original image was generated 38 0x9004 : "DateTimeDigitized", // Date and time when the image was stored digitally 39 0x9290 : "SubsecTime", // Fractions of seconds for DateTime 40 0x9291 : "SubsecTimeOriginal", // Fractions of seconds for DateTimeOriginal 41 0x9292 : "SubsecTimeDigitized", // Fractions of seconds for DateTimeDigitized 42 43 // picture-taking conditions 44 0x829A : "ExposureTime", // Exposure time (in seconds) 45 0x829D : "FNumber", // F number 46 0x8822 : "ExposureProgram", // Exposure program 47 0x8824 : "SpectralSensitivity", // Spectral sensitivity 48 0x8827 : "ISOSpeedRatings", // ISO speed rating 49 0x8828 : "OECF", // Optoelectric conversion factor 50 0x9201 : "ShutterSpeedValue", // Shutter speed 51 0x9202 : "ApertureValue", // Lens aperture 52 0x9203 : "BrightnessValue", // Value of brightness 53 0x9204 : "ExposureBias", // Exposure bias 54 0x9205 : "MaxApertureValue", // Smallest F number of lens 55 0x9206 : "SubjectDistance", // Distance to subject in meters 56 0x9207 : "MeteringMode", // Metering mode 57 0x9208 : "LightSource", // Kind of light source 58 0x9209 : "Flash", // Flash status 59 0x9214 : "SubjectArea", // Location and area of main subject 60 0x920A : "FocalLength", // Focal length of the lens in mm 61 0xA20B : "FlashEnergy", // Strobe energy in BCPS 62 0xA20C : "SpatialFrequencyResponse", // 63 0xA20E : "FocalPlaneXResolution", // Number of pixels in width direction per FocalPlaneResolutionUnit 64 0xA20F : "FocalPlaneYResolution", // Number of pixels in height direction per FocalPlaneResolutionUnit 65 0xA210 : "FocalPlaneResolutionUnit", // Unit for measuring FocalPlaneXResolution and FocalPlaneYResolution 66 0xA214 : "SubjectLocation", // Location of subject in image 67 0xA215 : "ExposureIndex", // Exposure index selected on camera 68 0xA217 : "SensingMethod", // Image sensor type 69 0xA300 : "FileSource", // Image source (3 == DSC) 70 0xA301 : "SceneType", // Scene type (1 == directly photographed) 71 0xA302 : "CFAPattern", // Color filter array geometric pattern 72 0xA401 : "CustomRendered", // Special processing 73 0xA402 : "ExposureMode", // Exposure mode 74 0xA403 : "WhiteBalance", // 1 = auto white balance, 2 = manual 75 0xA404 : "DigitalZoomRation", // Digital zoom ratio 76 0xA405 : "FocalLengthIn35mmFilm", // Equivalent foacl length assuming 35mm film camera (in mm) 77 0xA406 : "SceneCaptureType", // Type of scene 78 0xA407 : "GainControl", // Degree of overall image gain adjustment 79 0xA408 : "Contrast", // Direction of contrast processing applied by camera 80 0xA409 : "Saturation", // Direction of saturation processing applied by camera 81 0xA40A : "Sharpness", // Direction of sharpness processing applied by camera 82 0xA40B : "DeviceSettingDescription", // 83 0xA40C : "SubjectDistanceRange", // Distance to subject 84 85 // other tags 86 0xA005 : "InteroperabilityIFDPointer", 87 0xA420 : "ImageUniqueID" // Identifier assigned uniquely to each image 88}; 89 90EXIF.TiffTags = { 91 0x0100 : "ImageWidth", 92 0x0101 : "ImageHeight", 93 0x8769 : "ExifIFDPointer", 94 0x8825 : "GPSInfoIFDPointer", 95 0xA005 : "InteroperabilityIFDPointer", 96 0x0102 : "BitsPerSample", 97 0x0103 : "Compression", 98 0x0106 : "PhotometricInterpretation", 99 0x0112 : "Orientation", 100 0x0115 : "SamplesPerPixel", 101 0x011C : "PlanarConfiguration", 102 0x0212 : "YCbCrSubSampling", 103 0x0213 : "YCbCrPositioning", 104 0x011A : "XResolution", 105 0x011B : "YResolution", 106 0x0128 : "ResolutionUnit", 107 0x0111 : "StripOffsets", 108 0x0116 : "RowsPerStrip", 109 0x0117 : "StripByteCounts", 110 0x0201 : "JPEGInterchangeFormat", 111 0x0202 : "JPEGInterchangeFormatLength", 112 0x012D : "TransferFunction", 113 0x013E : "WhitePoint", 114 0x013F : "PrimaryChromaticities", 115 0x0211 : "YCbCrCoefficients", 116 0x0214 : "ReferenceBlackWhite", 117 0x0132 : "DateTime", 118 0x010E : "ImageDescription", 119 0x010F : "Make", 120 0x0110 : "Model", 121 0x0131 : "Software", 122 0x013B : "Artist", 123 0x8298 : "Copyright" 124} 125 126EXIF.GPSTags = { 127 0x0000 : "GPSVersionID", 128 0x0001 : "GPSLatitudeRef", 129 0x0002 : "GPSLatitude", 130 0x0003 : "GPSLongitudeRef", 131 0x0004 : "GPSLongitude", 132 0x0005 : "GPSAltitudeRef", 133 0x0006 : "GPSAltitude", 134 0x0007 : "GPSTimeStamp", 135 0x0008 : "GPSSatellites", 136 0x0009 : "GPSStatus", 137 0x000A : "GPSMeasureMode", 138 0x000B : "GPSDOP", 139 0x000C : "GPSSpeedRef", 140 0x000D : "GPSSpeed", 141 0x000E : "GPSTrackRef", 142 0x000F : "GPSTrack", 143 0x0010 : "GPSImgDirectionRef", 144 0x0011 : "GPSImgDirection", 145 0x0012 : "GPSMapDatum", 146 0x0013 : "GPSDestLatitudeRef", 147 0x0014 : "GPSDestLatitude", 148 0x0015 : "GPSDestLongitudeRef", 149 0x0016 : "GPSDestLongitude", 150 0x0017 : "GPSDestBearingRef", 151 0x0018 : "GPSDestBearing", 152 0x0019 : "GPSDestDistanceRef", 153 0x001A : "GPSDestDistance", 154 0x001B : "GPSProcessingMethod", 155 0x001C : "GPSAreaInformation", 156 0x001D : "GPSDateStamp", 157 0x001E : "GPSDifferential" 158} 159 160EXIF.StringValues = { 161 ExposureProgram : { 162 0 : "Not defined", 163 1 : "Manual", 164 2 : "Normal program", 165 3 : "Aperture priority", 166 4 : "Shutter priority", 167 5 : "Creative program", 168 6 : "Action program", 169 7 : "Portrait mode", 170 8 : "Landscape mode" 171 }, 172 MeteringMode : { 173 0 : "Unknown", 174 1 : "Average", 175 2 : "CenterWeightedAverage", 176 3 : "Spot", 177 4 : "MultiSpot", 178 5 : "Pattern", 179 6 : "Partial", 180 255 : "Other" 181 }, 182 LightSource : { 183 0 : "Unknown", 184 1 : "Daylight", 185 2 : "Fluorescent", 186 3 : "Tungsten (incandescent light)", 187 4 : "Flash", 188 9 : "Fine weather", 189 10 : "Cloudy weather", 190 11 : "Shade", 191 12 : "Daylight fluorescent (D 5700 - 7100K)", 192 13 : "Day white fluorescent (N 4600 - 5400K)", 193 14 : "Cool white fluorescent (W 3900 - 4500K)", 194 15 : "White fluorescent (WW 3200 - 3700K)", 195 17 : "Standard light A", 196 18 : "Standard light B", 197 19 : "Standard light C", 198 20 : "D55", 199 21 : "D65", 200 22 : "D75", 201 23 : "D50", 202 24 : "ISO studio tungsten", 203 255 : "Other" 204 }, 205 Flash : { 206 0x0000 : "Flash did not fire", 207 0x0001 : "Flash fired", 208 0x0005 : "Strobe return light not detected", 209 0x0007 : "Strobe return light detected", 210 0x0009 : "Flash fired, compulsory flash mode", 211 0x000D : "Flash fired, compulsory flash mode, return light not detected", 212 0x000F : "Flash fired, compulsory flash mode, return light detected", 213 0x0010 : "Flash did not fire, compulsory flash mode", 214 0x0018 : "Flash did not fire, auto mode", 215 0x0019 : "Flash fired, auto mode", 216 0x001D : "Flash fired, auto mode, return light not detected", 217 0x001F : "Flash fired, auto mode, return light detected", 218 0x0020 : "No flash function", 219 0x0041 : "Flash fired, red-eye reduction mode", 220 0x0045 : "Flash fired, red-eye reduction mode, return light not detected", 221 0x0047 : "Flash fired, red-eye reduction mode, return light detected", 222 0x0049 : "Flash fired, compulsory flash mode, red-eye reduction mode", 223 0x004D : "Flash fired, compulsory flash mode, red-eye reduction mode, return light not detected", 224 0x004F : "Flash fired, compulsory flash mode, red-eye reduction mode, return light detected", 225 0x0059 : "Flash fired, auto mode, red-eye reduction mode", 226 0x005D : "Flash fired, auto mode, return light not detected, red-eye reduction mode", 227 0x005F : "Flash fired, auto mode, return light detected, red-eye reduction mode" 228 }, 229 SensingMethod : { 230 1 : "Not defined", 231 2 : "One-chip color area sensor", 232 3 : "Two-chip color area sensor", 233 4 : "Three-chip color area sensor", 234 5 : "Color sequential area sensor", 235 7 : "Trilinear sensor", 236 8 : "Color sequential linear sensor" 237 }, 238 SceneCaptureType : { 239 0 : "Standard", 240 1 : "Landscape", 241 2 : "Portrait", 242 3 : "Night scene" 243 }, 244 SceneType : { 245 1 : "Directly photographed" 246 }, 247 CustomRendered : { 248 0 : "Normal process", 249 1 : "Custom process" 250 }, 251 WhiteBalance : { 252 0 : "Auto white balance", 253 1 : "Manual white balance" 254 }, 255 GainControl : { 256 0 : "None", 257 1 : "Low gain up", 258 2 : "High gain up", 259 3 : "Low gain down", 260 4 : "High gain down" 261 }, 262 Contrast : { 263 0 : "Normal", 264 1 : "Soft", 265 2 : "Hard" 266 }, 267 Saturation : { 268 0 : "Normal", 269 1 : "Low saturation", 270 2 : "High saturation" 271 }, 272 Sharpness : { 273 0 : "Normal", 274 1 : "Soft", 275 2 : "Hard" 276 }, 277 SubjectDistanceRange : { 278 0 : "Unknown", 279 1 : "Macro", 280 2 : "Close view", 281 3 : "Distant view" 282 }, 283 FileSource : { 284 3 : "DSC" 285 }, 286 287 Components : { 288 0 : "", 289 1 : "Y", 290 2 : "Cb", 291 3 : "Cr", 292 4 : "R", 293 5 : "G", 294 6 : "B" 295 } 296} 297 298function addEvent(oElement, strEvent, fncHandler) 299{ 300 if (oElement.addEventListener) { 301 oElement.addEventListener(strEvent, fncHandler, false); 302 } else if (oElement.attachEvent) { 303 oElement.attachEvent("on" + strEvent, fncHandler); 304 } 305} 306 307 308function imageHasData(oImg) 309{ 310 return !!(oImg.exifdata); 311} 312 313function getImageData(oImg, fncCallback) 314{ 315 BinaryAjax( 316 oImg.src, 317 function(oHTTP) { 318 var oEXIF = findEXIFinJPEG(oHTTP.binaryResponse); 319 oImg.exifdata = oEXIF || {}; 320 if (fncCallback) fncCallback(); 321 } 322 ) 323} 324 325function findEXIFinJPEG(oFile) { 326 var aMarkers = []; 327 328 if (oFile.getByteAt(0) != 0xFF || oFile.getByteAt(1) != 0xD8) { 329 return false; // not a valid jpeg 330 } 331 332 var iOffset = 2; 333 var iLength = oFile.getLength(); 334 while (iOffset < iLength) { 335 if (oFile.getByteAt(iOffset) != 0xFF) { 336 if (bDebug) console.log("Not a valid marker at offset " + iOffset + ", found: " + oFile.getByteAt(iOffset)); 337 return false; // not a valid marker, something is wrong 338 } 339 340 var iMarker = oFile.getByteAt(iOffset+1); 341 342 // we could implement handling for other markers here, 343 // but we're only looking for 0xFFE1 for EXIF data 344 345 if (iMarker == 22400) { 346 if (bDebug) console.log("Found 0xFFE1 marker"); 347 return readEXIFData(oFile, iOffset + 4, oFile.getShortAt(iOffset+2, true)-2); 348 iOffset += 2 + oFile.getShortAt(iOffset+2, true); 349 350 } else if (iMarker == 225) { 351 // 0xE1 = Application-specific 1 (for EXIF) 352 if (bDebug) console.log("Found 0xFFE1 marker"); 353 return readEXIFData(oFile, iOffset + 4, oFile.getShortAt(iOffset+2, true)-2); 354 355 } else { 356 iOffset += 2 + oFile.getShortAt(iOffset+2, true); 357 } 358 359 } 360 361} 362 363 364function readTags(oFile, iTIFFStart, iDirStart, oStrings, bBigEnd) 365{ 366 var iEntries = oFile.getShortAt(iDirStart, bBigEnd); 367 var oTags = {}; 368 for (var i=0;i<iEntries;i++) { 369 var iEntryOffset = iDirStart + i*12 + 2; 370 var strTag = oStrings[oFile.getShortAt(iEntryOffset, bBigEnd)]; 371 if (!strTag && bDebug) console.log("Unknown tag: " + oFile.getShortAt(iEntryOffset, bBigEnd)); 372 oTags[strTag] = readTagValue(oFile, iEntryOffset, iTIFFStart, iDirStart, bBigEnd); 373 } 374 return oTags; 375} 376 377 378function readTagValue(oFile, iEntryOffset, iTIFFStart, iDirStart, bBigEnd) 379{ 380 var iType = oFile.getShortAt(iEntryOffset+2, bBigEnd); 381 var iNumValues = oFile.getLongAt(iEntryOffset+4, bBigEnd); 382 var iValueOffset = oFile.getLongAt(iEntryOffset+8, bBigEnd) + iTIFFStart; 383 384 switch (iType) { 385 case 1: // byte, 8-bit unsigned int 386 case 7: // undefined, 8-bit byte, value depending on field 387 if (iNumValues == 1) { 388 return oFile.getByteAt(iEntryOffset + 8, bBigEnd); 389 } else { 390 var iValOffset = iNumValues > 4 ? iValueOffset : (iEntryOffset + 8); 391 var aVals = []; 392 for (var n=0;n<iNumValues;n++) { 393 aVals[n] = oFile.getByteAt(iValOffset + n); 394 } 395 return aVals; 396 } 397 break; 398 399 case 2: // ascii, 8-bit byte 400 var iStringOffset = iNumValues > 4 ? iValueOffset : (iEntryOffset + 8); 401 return oFile.getStringAt(iStringOffset, iNumValues-1); 402 break; 403 404 case 3: // short, 16 bit int 405 if (iNumValues == 1) { 406 return oFile.getShortAt(iEntryOffset + 8, bBigEnd); 407 } else { 408 var iValOffset = iNumValues > 2 ? iValueOffset : (iEntryOffset + 8); 409 var aVals = []; 410 for (var n=0;n<iNumValues;n++) { 411 aVals[n] = oFile.getShortAt(iValOffset + 2*n, bBigEnd); 412 } 413 return aVals; 414 } 415 break; 416 417 case 4: // long, 32 bit int 418 if (iNumValues == 1) { 419 return oFile.getLongAt(iEntryOffset + 8, bBigEnd); 420 } else { 421 var aVals = []; 422 for (var n=0;n<iNumValues;n++) { 423 aVals[n] = oFile.getLongAt(iValueOffset + 4*n, bBigEnd); 424 } 425 return aVals; 426 } 427 break; 428 case 5: // rational = two long values, first is numerator, second is denominator 429 if (iNumValues == 1) { 430 return oFile.getLongAt(iValueOffset, bBigEnd) / oFile.getLongAt(iValueOffset+4, bBigEnd); 431 } else { 432 var aVals = []; 433 for (var n=0;n<iNumValues;n++) { 434 aVals[n] = oFile.getLongAt(iValueOffset + 8*n, bBigEnd) / oFile.getLongAt(iValueOffset+4 + 8*n, bBigEnd); 435 } 436 return aVals; 437 } 438 break; 439 case 9: // slong, 32 bit signed int 440 if (iNumValues == 1) { 441 return oFile.getSLongAt(iEntryOffset + 8, bBigEnd); 442 } else { 443 var aVals = []; 444 for (var n=0;n<iNumValues;n++) { 445 aVals[n] = oFile.getSLongAt(iValueOffset + 4*n, bBigEnd); 446 } 447 return aVals; 448 } 449 break; 450 case 10: // signed rational, two slongs, first is numerator, second is denominator 451 if (iNumValues == 1) { 452 return oFile.getSLongAt(iValueOffset, bBigEnd) / oFile.getSLongAt(iValueOffset+4, bBigEnd); 453 } else { 454 var aVals = []; 455 for (var n=0;n<iNumValues;n++) { 456 aVals[n] = oFile.getSLongAt(iValueOffset + 8*n, bBigEnd) / oFile.getSLongAt(iValueOffset+4 + 8*n, bBigEnd); 457 } 458 return aVals; 459 } 460 break; 461 } 462} 463 464 465function readEXIFData(oFile, iStart, iLength) 466{ 467 if (oFile.getStringAt(iStart, 4) != "Exif") { 468 if (bDebug) console.log("Not valid EXIF data! " + oFile.getStringAt(iStart, 4)); 469 return false; 470 } 471 472 var bBigEnd; 473 474 var iTIFFOffset = iStart + 6; 475 476 // test for TIFF validity and endianness 477 if (oFile.getShortAt(iTIFFOffset) == 0x4949) { 478 bBigEnd = false; 479 } else if (oFile.getShortAt(iTIFFOffset) == 0x4D4D) { 480 bBigEnd = true; 481 } else { 482 if (bDebug) console.log("Not valid TIFF data! (no 0x4949 or 0x4D4D)"); 483 return false; 484 } 485 486 if (oFile.getShortAt(iTIFFOffset+2, bBigEnd) != 0x002A) { 487 if (bDebug) console.log("Not valid TIFF data! (no 0x002A)"); 488 return false; 489 } 490 491 if (oFile.getLongAt(iTIFFOffset+4, bBigEnd) != 0x00000008) { 492 if (bDebug) console.log("Not valid TIFF data! (First offset not 8)", oFile.getShortAt(iTIFFOffset+4, bBigEnd)); 493 return false; 494 } 495 496 var oTags = readTags(oFile, iTIFFOffset, iTIFFOffset+8, EXIF.TiffTags, bBigEnd); 497 498 if (oTags.ExifIFDPointer) { 499 var oEXIFTags = readTags(oFile, iTIFFOffset, iTIFFOffset + oTags.ExifIFDPointer, EXIF.Tags, bBigEnd); 500 for (var strTag in oEXIFTags) { 501 switch (strTag) { 502 case "LightSource" : 503 case "Flash" : 504 case "MeteringMode" : 505 case "ExposureProgram" : 506 case "SensingMethod" : 507 case "SceneCaptureType" : 508 case "SceneType" : 509 case "CustomRendered" : 510 case "WhiteBalance" : 511 case "GainControl" : 512 case "Contrast" : 513 case "Saturation" : 514 case "Sharpness" : 515 case "SubjectDistanceRange" : 516 case "FileSource" : 517 oEXIFTags[strTag] = EXIF.StringValues[strTag][oEXIFTags[strTag]]; 518 break; 519 520 case "ExifVersion" : 521 case "FlashpixVersion" : 522 oEXIFTags[strTag] = String.fromCharCode(oEXIFTags[strTag][0], oEXIFTags[strTag][1], oEXIFTags[strTag][2], oEXIFTags[strTag][3]); 523 break; 524 525 case "ComponentsConfiguration" : 526 oEXIFTags[strTag] = 527 EXIF.StringValues.Components[oEXIFTags[strTag][0]] 528 + EXIF.StringValues.Components[oEXIFTags[strTag][1]] 529 + EXIF.StringValues.Components[oEXIFTags[strTag][2]] 530 + EXIF.StringValues.Components[oEXIFTags[strTag][3]]; 531 break; 532 } 533 oTags[strTag] = oEXIFTags[strTag]; 534 } 535 } 536 537 if (oTags.GPSInfoIFDPointer) { 538 var oGPSTags = readTags(oFile, iTIFFOffset, iTIFFOffset + oTags.GPSInfoIFDPointer, EXIF.GPSTags, bBigEnd); 539 for (var strTag in oGPSTags) { 540 switch (strTag) { 541 case "GPSVersionID" : 542 oGPSTags[strTag] = oGPSTags[strTag][0] 543 + "." + oGPSTags[strTag][1] 544 + "." + oGPSTags[strTag][2] 545 + "." + oGPSTags[strTag][3]; 546 break; 547 } 548 oTags[strTag] = oGPSTags[strTag]; 549 } 550 } 551 552 return oTags; 553} 554 555 556EXIF.getData = function(oImg, fncCallback) 557{ 558 if (!oImg.complete) return false; 559 if (!imageHasData(oImg)) { 560 getImageData(oImg, fncCallback); 561 } else { 562 if (fncCallback) fncCallback(); 563 } 564 return true; 565} 566 567EXIF.getTag = function(oImg, strTag) 568{ 569 if (!imageHasData(oImg)) return; 570 return oImg.exifdata[strTag]; 571} 572 573EXIF.pretty = function(oImg) 574{ 575 if (!imageHasData(oImg)) return ""; 576 var oData = oImg.exifdata; 577 var strPretty = ""; 578 for (var a in oData) { 579 if (oData.hasOwnProperty(a)) { 580 if (typeof oData[a] == "object") { 581 strPretty += a + " : [" + oData[a].length + " values]\r\n"; 582 } else { 583 strPretty += a + " : " + oData[a] + "\r\n"; 584 } 585 } 586 } 587 return strPretty; 588} 589 590EXIF.readFromBinaryFile = function(oFile) { 591 return findEXIFinJPEG(oFile); 592} 593 594function loadAllImages() 595{ 596 var aImages = document.getElementsByTagName("img"); 597 for (var i=0;i<aImages.length;i++) { 598 if (aImages[i].getAttribute("exif") == "true") { 599 if (!aImages[i].complete) { 600 addEvent(aImages[i], "load", 601 function() { 602 EXIF.getData(this); 603 } 604 ); 605 } else { 606 EXIF.getData(aImages[i]); 607 } 608 } 609 } 610} 611 612addEvent(window, "load", loadAllImages); 613 614})(); 615 616