src/exif.c

   1 /*
   2  *  GQView
   3  *  (C) 2004 John Ellis
   4  *
   5  *  Authors:
   6  *    Support for Exif file format, originally written by Eric Swalens.
   7  *    Modified by Quy Tonthat
   8  *
   9  *    Reimplemented with generic data storage by John Ellis (Nov 2003)
  10  *
  11  *  The tags were added with information from the FREE document:
  12  *     http://www.ba.wakwak.com/~tsuruzoh/Computer/Digicams/exif-e.html
  13  *
  14  *  For the official Exif Format, please refer to:
  15  *     http://www.exif.org
  16  *     http://www.exif.org/specifications.html (PDF spec sheets)
  17  *
  18  *  Notes:
  19  *     Additional tag formats should be added to the proper
  20  *     location in ExifKnownMarkersList[].
  21  *
  22  *     Human readable ouput (that needs additional processing of data to
  23  *     be useable) can be defined by adding a key to ExifFormattedList[],
  24  *     then handling that tag in the function exif_get_formatted_by_key().
  25  *     The human readable formatted keys must begin with the character 'f'.
  26  *
  27  *  Unsupported at this time:
  28  *     IFD1 (thumbnail)
  29  *     MakerNote
  30  *     GPSInfo
  31  *
  32  *  TODO:
  33  *     Convert data to useable form in the ??_as_text function for:
  34  *        ComponentsConfiguration
  35  *        UserComment (convert this to UTF-8?)
  36  *
  37
  38     This program is free software; you can redistribute it and/or modify
  39     it under the terms of the GNU General Public License as published by
  40     the Free Software Foundation; either version 2 of the License, or
  41     (at your option) any later version.
  42
  43     This program is distributed in the hope that it will be useful,
  44     but WITHOUT ANY WARRANTY; without even the implied warranty of
  45     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  46     GNU General Public License for more details.
  47
  48     You should have received a copy of the GNU General Public License
  49     along with this program; if not, write to the Free Software
  50     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  51 */
  52
  53 #ifdef HAVE_CONFIG_H
  54 #  include "config.h"
  55 #endif
  56
  57 #include <stdio.h>
  58 #include <inttypes.h>   /* stdint.h is not available on all systems... */
  59 #include <string.h>
  60 #include <fcntl.h>
  61 #include <unistd.h>
  62 #include <sys/types.h>
  63 #include <sys/stat.h>
  64 #include <sys/mman.h>
  65 #include <math.h>
  66
  67 #include <glib.h>
  68
  69 #include "intl.h"
  70
  71 #include "exif.h"
  72
  73 #include "ui_fileops.h"
  74
  75
  76 /*
  77  *-----------------------------------------------------------------------------
  78  * Tag formats
  79  *-----------------------------------------------------------------------------
  80  */
  81
  82 ExifFormatAttrib ExifFormatList[] = {
  83         { EXIF_FORMAT_UNKNOWN,          1, "unknown",   "unknown" },
  84         { EXIF_FORMAT_BYTE_UNSIGNED,    1, "ubyte",     "unsigned byte" },
  85         { EXIF_FORMAT_STRING,           1, "string",    "string" },
  86         { EXIF_FORMAT_SHORT_UNSIGNED,   2, "ushort",    "unsigned short" },
  87         { EXIF_FORMAT_LONG_UNSIGNED,    4, "ulong",     "unsigned long" },
  88         { EXIF_FORMAT_RATIONAL_UNSIGNED,8, "urational", "unsigned rational" },
  89         { EXIF_FORMAT_BYTE,             1, "byte",      "byte" },
  90         { EXIF_FORMAT_UNDEFINED,        1, "undefined", "undefined" },
  91         { EXIF_FORMAT_SHORT,            2, "sshort",    "signed short" },
  92         { EXIF_FORMAT_LONG,             4, "slong",     "signed long" },
  93         { EXIF_FORMAT_RATIONAL,         8, "srational", "signed rational" },
  94         { EXIF_FORMAT_FLOAT,            4, "float",     "float" },
  95         { EXIF_FORMAT_DOUBLE,           8, "double",    "double" },
  96         { -1, 0, NULL }
  97 };
  98
  99 /* tags that are special, or need special treatment */
 100 #define TAG_EXIFOFFSET          0x8769
 101
 102
 103 /*
 104  *-----------------------------------------------------------------------------
 105  * Data
 106  *-----------------------------------------------------------------------------
 107  */
 108
 109 #define EXIF_TEXT_LIST_END { -1, NULL }
 110
 111 static ExifTextList ExifOrientationList[] = {
 112         { EXIF_ORIENTATION_UNKNOWN,     N_("unknown") },
 113         { EXIF_ORIENTATION_TOP_LEFT,    N_("top left") },
 114         { EXIF_ORIENTATION_TOP_RIGHT,   N_("top right") },
 115         { EXIF_ORIENTATION_BOTTOM_RIGHT,N_("bottom right") },
 116         { EXIF_ORIENTATION_BOTTOM_LEFT, N_("bottom left") },
 117         { EXIF_ORIENTATION_LEFT_TOP,    N_("left top") },
 118         { EXIF_ORIENTATION_RIGHT_TOP,   N_("right top") },
 119         { EXIF_ORIENTATION_RIGHT_BOTTOM,N_("right bottom") },
 120         { EXIF_ORIENTATION_LEFT_BOTTOM, N_("left bottom") },
 121         EXIF_TEXT_LIST_END
 122 };
 123
 124 static ExifTextList ExifUnitList[] = {
 125         { EXIF_UNIT_UNKNOWN,    N_("unknown") },
 126         { EXIF_UNIT_NOUNIT,     "" },
 127         { EXIF_UNIT_INCH,       N_("inch") },
 128         { EXIF_UNIT_CENTIMETER, N_("centimeter") },
 129         EXIF_TEXT_LIST_END
 130 };
 131
 132 static ExifTextList ExifYCbCrPosList[] = {
 133         { 1,    "center" },
 134         { 2,    "datum" },
 135         EXIF_TEXT_LIST_END
 136 };
 137
 138 static ExifTextList ExifMeteringModeList[] = {
 139         { 0,    N_("unknown") },
 140         { 1,    N_("average") },
 141         { 2,    N_("center weighted") },
 142         { 3,    N_("spot") },
 143         { 4,    N_("multi-spot") },
 144         { 5,    N_("multi-segment") },
 145         { 6,    N_("partial") },
 146         { 255,  N_("other") },
 147         EXIF_TEXT_LIST_END
 148 };
 149
 150 static ExifTextList ExifExposureProgramList[] = {
 151         { 0,    N_("not defined") },
 152         { 1,    N_("manual") },
 153         { 2,    N_("normal") },
 154         { 3,    N_("aperture") },
 155         { 4,    N_("shutter") },
 156         { 5,    N_("creative") },
 157         { 6,    N_("action") },
 158         { 7,    N_("portrait") },
 159         { 8,    N_("landscape") },
 160         EXIF_TEXT_LIST_END
 161 };
 162
 163 static ExifTextList ExifLightSourceList[] = {
 164         { 0,    N_("unknown") },
 165         { 1,    N_("daylight") },
 166         { 2,    N_("fluorescent") },
 167         { 3,    N_("tungsten (incandescent)") },
 168         { 4,    N_("flash") },
 169         { 9,    "fine weather" },
 170         { 10,   "cloudy weather" },
 171         { 11,   "shade" },
 172         { 12,   "daylight fluorescent" },
 173         { 13,   "day white fluorescent" },
 174         { 14,   "cool white fluorescent" },
 175         { 15,   "while fluorescent" },
 176         { 17,   "standard light A" },
 177         { 18,   "standard light B" },
 178         { 19,   "standard light C" },
 179         { 20,   "D55" },
 180         { 21,   "D65" },
 181         { 22,   "D75" },
 182         { 23,   "D50" },
 183         { 24,   "ISO studio tungsten" },
 184         { 255,  N_("other") },
 185         EXIF_TEXT_LIST_END
 186 };
 187
 188 static ExifTextList ExifFlashList[] = {
 189         { 0,    N_("no") },
 190         { 1,    N_("yes") },
 191         { 5,    N_("yes, not detected by strobe") },
 192         { 7,    N_("yes, detected by strobe") },
 193         EXIF_TEXT_LIST_END
 194 };
 195
 196 static ExifTextList ExifColorSpaceList[] = {
 197         { 1,    "sRGB" },
 198         { 65535,"uncalibrated" },
 199         EXIF_TEXT_LIST_END
 200 };
 201
 202 static ExifTextList ExifSensorList[] = {
 203         { 1,    "not defined" },
 204         { 2,    "1 chip color area" },
 205         { 2,    "2 chip color area" },
 206         { 4,    "3 chip color area" },
 207         { 5,    "color sequential area" },
 208         { 7,    "trilinear" },
 209         { 8,    "color sequential linear" },
 210         EXIF_TEXT_LIST_END
 211 };
 212
 213 static ExifTextList ExifSourceList[] = {
 214         { 3,    "digital still camera" },
 215         EXIF_TEXT_LIST_END
 216 };
 217
 218 static ExifTextList ExifSceneList[] = {
 219         { 1,    "direct photo" },
 220         EXIF_TEXT_LIST_END
 221 };
 222
 223 static ExifTextList ExifCustRenderList[] = {
 224         { 0,    "normal" },
 225         { 1,    "custom" },
 226         EXIF_TEXT_LIST_END
 227 };
 228
 229 static ExifTextList ExifExposureModeList[] = {
 230         { 0,    "auto" },
 231         { 1,    "manual" },
 232         { 2,    "auto bracket" },
 233         EXIF_TEXT_LIST_END
 234 };
 235
 236 static ExifTextList ExifWhiteBalanceList[] = {
 237         { 0,    "auto" },
 238         { 1,    "manual" },
 239         EXIF_TEXT_LIST_END
 240 };
 241
 242 static ExifTextList ExifSceneCaptureList[] = {
 243         { 0,    "standard" },
 244         { 1,    "landscape" },
 245         { 2,    "portrait" },
 246         { 3,    "night scene" },
 247         EXIF_TEXT_LIST_END
 248 };
 249
 250 static ExifTextList ExifGainControlList[] = {
 251         { 0,    "none" },
 252         { 1,    "low gain up" },
 253         { 2,    "high gain up" },
 254         { 3,    "low gain down" },
 255         { 4,    "high gain down" },
 256         EXIF_TEXT_LIST_END
 257 };
 258
 259 static ExifTextList ExifContrastList[] = {
 260         { 0,    "normal" },
 261         { 1,    "soft" },
 262         { 2,    "hard" },
 263         EXIF_TEXT_LIST_END
 264 };
 265
 266 static ExifTextList ExifSaturationList[] = {
 267         { 0,    "normal" },
 268         { 1,    "low" },
 269         { 2,    "high" },
 270         EXIF_TEXT_LIST_END
 271 };
 272
 273 static ExifTextList ExifSharpnessList[] = {
 274         { 0,    "normal" },
 275         { 1,    "soft" },
 276         { 2,    "hard" },
 277         EXIF_TEXT_LIST_END
 278 };
 279
 280 static ExifTextList ExifSubjectRangeList[] = {
 281         { 0,    "unknown" },
 282         { 1,    "macro" },
 283         { 2,    "close" },
 284         { 3,    "distant" },
 285         EXIF_TEXT_LIST_END
 286 };
 287
 288 ExifMarker ExifKnownMarkersList[] = {
 289 { 0x010e, EXIF_FORMAT_STRING, -1,               "ImageDescription",     N_("Image description"), NULL },
 290 { 0x010f, EXIF_FORMAT_STRING, -1,               "Make",                 "Camera make", NULL },
 291 { 0x0110, EXIF_FORMAT_STRING, -1,               "Model",                "Camera model", NULL },
 292 { 0x0112, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "Orientation",          N_("Orientation"), ExifOrientationList },
 293 { 0x011a, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "XResolution",          "X resolution", NULL },
 294 { 0x011b, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "YResolution",          "Y Resolution", NULL },
 295 { 0x0128, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "ResolutionUnit",       "Resolution units", ExifUnitList },
 296 { 0x0131, EXIF_FORMAT_STRING, -1,               "Software",             "Firmware", NULL },
 297 { 0x0132, EXIF_FORMAT_STRING, 20,               "DateTime",             N_("Date"), NULL },
 298 { 0x013e, EXIF_FORMAT_RATIONAL_UNSIGNED, 2,     "WhitePoint",           "White point", NULL },
 299 { 0x013f, EXIF_FORMAT_RATIONAL_UNSIGNED, 6,     "PrimaryChromaticities","Primary chromaticities", NULL },
 300 { 0x0211, EXIF_FORMAT_RATIONAL_UNSIGNED, 3,     "YCbCrCoefficients",    "YCbCy coefficients", NULL },
 301 { 0x0213, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "YCbCrPositioning",     "YCbCr positioning", ExifYCbCrPosList },
 302 { 0x0214, EXIF_FORMAT_RATIONAL_UNSIGNED, 6,     "ReferenceBlackWhite",  "Black white reference", NULL },
 303 { 0x8298, EXIF_FORMAT_STRING, -1,               "Copyright",            N_("Copyright"), NULL },
 304 { 0x8769, EXIF_FORMAT_LONG_UNSIGNED, 1,         "ExifOffset",           "SubIFD Exif offset", NULL },
 305         /* subIFD follows */
 306 { 0x829a, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "ExposureTime",         "Exposure time (seconds)", NULL },
 307 { 0x829d, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "FNumber",              "FNumber", NULL },
 308 { 0x8822, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "ExposureProgram",      N_("Exposure program"), ExifExposureProgramList },
 309 { 0x8824, EXIF_FORMAT_STRING, -1,               "SpectralSensitivity",  "Spectral Sensitivity", NULL },
 310 { 0x8827, EXIF_FORMAT_SHORT_UNSIGNED, -1,       "ISOSpeedRatings",      N_("ISO sensitivity"), NULL },
 311 { 0x8828, EXIF_FORMAT_UNDEFINED, -1,            "OECF",                 "Optoelectric conversion factor", NULL },
 312 { 0x9000, EXIF_FORMAT_UNDEFINED, 4,             "ExifVersion",          "Exif version", NULL },
 313 { 0x9003, EXIF_FORMAT_STRING, 20,               "DateTimeOriginal",     N_("Date original"), NULL },
 314 { 0x9004, EXIF_FORMAT_STRING, 20,               "DateTimeDigitized",    N_("Date digitized"), NULL },
 315 { 0x9101, EXIF_FORMAT_UNDEFINED, -1,            "ComponentsConfiguration","Pixel format", NULL },
 316 { 0x9102, EXIF_FORMAT_RATIONAL_UNSIGNED,1,      "CompressedBitsPerPixel","Compression ratio", NULL },
 317 { 0x9201, EXIF_FORMAT_RATIONAL, 1,              "ShutterSpeedValue",    N_("Shutter speed"), NULL },
 318 { 0x9202, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "ApertureValue",        N_("Aperture"), NULL },
 319 { 0x9203, EXIF_FORMAT_RATIONAL, 1,              "BrightnessValue",      "Brightness", NULL },
 320 { 0x9204, EXIF_FORMAT_RATIONAL, 1,              "ExposureBiasValue",    N_("Exposure bias"), NULL },
 321 { 0x9205, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "MaxApertureValue",     "Maximum aperture", NULL },
 322 { 0x9206, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "SubjectDistance",      N_("Subject distance"), NULL },
 323 { 0x9207, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "MeteringMode",         N_("Metering mode"), ExifMeteringModeList },
 324 { 0x9208, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "LightSource",          N_("Light source"), ExifLightSourceList },
 325 { 0x9209, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "Flash",                N_("Flash"), ExifFlashList },
 326 { 0x920a, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "FocalLength",          N_("Focal length"), NULL },
 327 { 0x9214, EXIF_FORMAT_SHORT_UNSIGNED, -1,       "SubjectArea",          "Subject area", NULL },
 328 { 0x927c, EXIF_FORMAT_UNDEFINED, -1,            "MakerNote",            "MakerNote", NULL },
 329 { 0x9286, EXIF_FORMAT_UNDEFINED, -1,            "UserComment",          "UserComment", NULL },
 330 { 0x9290, EXIF_FORMAT_STRING, -1,               "SubsecTime",           "Subsecond time", NULL },
 331 { 0x9291, EXIF_FORMAT_STRING, -1,               "SubsecTimeOriginal",   "Subsecond time original", NULL },
 332 { 0x9292, EXIF_FORMAT_STRING, -1,               "SubsecTimeDigitized",  "Subsecond time digitized", NULL },
 333 { 0xa000, EXIF_FORMAT_UNDEFINED, 4,             "FlashPixVersion",      "FlashPix version", NULL },
 334 { 0xa001, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "ColorSpace",           "Colorspace", ExifColorSpaceList },
 335         /* ExifImageWidth, ExifImageHeight can also be unsigned short */
 336 { 0xa002, EXIF_FORMAT_LONG_UNSIGNED, 1,         "ExifImageWidth",       N_("Width"), NULL },
 337 { 0xa003, EXIF_FORMAT_LONG_UNSIGNED, 1,         "ExifImageHeight",      N_("Height"), NULL },
 338 { 0xa004, EXIF_FORMAT_STRING, -1,               "RelatedSoundFile",     "Audio data", NULL },
 339 { 0xa005, EXIF_FORMAT_LONG_UNSIGNED, 1,         "ExifInteroperabilityOffset", "ExifR98 extension", NULL },
 340 { 0xa20b, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "FlashEnergy",          "Flash strength", NULL },
 341 { 0xa20c, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "SpatialFrequencyResponse","Spatial frequency response", NULL },
 342 { 0xa20e, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "FocalPlaneXResolution", "X Pixel density", NULL },
 343 { 0xa20f, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "FocalPlaneYResolution", "Y Pixel density", NULL },
 344 { 0xa210, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "FocalPlaneResolutionUnit", "Pixel density units", ExifUnitList },
 345 { 0x0214, EXIF_FORMAT_SHORT_UNSIGNED, 2,        "SubjectLocation",      "Subject location", NULL },
 346 { 0xa215, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "ExposureIndex",        N_("ISO sensitivity"), NULL },
 347 { 0xa217, EXIF_FORMAT_SHORT_UNSIGNED, -1,       "SensingMethod",        "Sensor type", ExifSensorList },
 348 { 0xa300, EXIF_FORMAT_UNDEFINED, 1,             "FileSource",           "Source type", ExifSourceList },
 349 { 0xa301, EXIF_FORMAT_UNDEFINED, 1,             "SceneType",            "Scene type", ExifSceneList },
 350 { 0xa302, EXIF_FORMAT_UNDEFINED, -1,            "CFAPattern",           "Color filter array pattern", NULL },
 351         /* tags a4xx were added for Exif 2.2 (not just these - some above, as well) */
 352 { 0xa401, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "CustomRendered",       "Render process", ExifCustRenderList },
 353 { 0xa402, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "ExposureMode",         "Exposure mode", ExifExposureModeList },
 354 { 0xa403, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "WhiteBalance",         "White balance", ExifWhiteBalanceList },
 355 { 0xa404, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "DigitalZoomRatio",     "Digital zoom ratio", NULL },
 356 { 0xa405, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "FocalLength35mmFilm",  "Focal length (35mm)", NULL },
 357 { 0xa406, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "SceneCapturetype",     "Scene capture type", ExifSceneCaptureList },
 358 { 0xa407, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "GainControl",          "Gain control", ExifGainControlList },
 359 { 0xa408, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "Contrast",             "Contrast", ExifContrastList },
 360 { 0xa409, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "Saturation",           "Saturation", ExifSaturationList },
 361 { 0xa40a, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "Sharpness",            "Sharpness", ExifSharpnessList },
 362 { 0xa40b, EXIF_FORMAT_UNDEFINED, -1,            "DeviceSettingDescription","Device setting", NULL },
 363 { 0xa40c, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "SubjectDistanceRange", "Subject range", ExifSubjectRangeList },
 364 { 0xa420, EXIF_FORMAT_STRING, -1,               "ImageUniqueID",        "Image serial number", NULL },
 365         /* place known, but undocumented or lesser used tags here */
 366 { 0x00fe, EXIF_FORMAT_LONG_UNSIGNED, 1,         "NewSubfileType",       NULL, NULL },
 367 { 0x00ff, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "SubfileType",          NULL, NULL },
 368 { 0x012d, EXIF_FORMAT_SHORT_UNSIGNED, 3,        "TransferFunction",     NULL, NULL },
 369 { 0x013b, EXIF_FORMAT_STRING, -1,               "Artist",               "Artist", NULL },
 370 { 0x013d, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "Predictor",            NULL, NULL },
 371 { 0x0142, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "TileWidth",            NULL, NULL },
 372 { 0x0143, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "TileLength",           NULL, NULL },
 373 { 0x0144, EXIF_FORMAT_LONG_UNSIGNED, -1,        "TileOffsets",          NULL, NULL },
 374 { 0x0145, EXIF_FORMAT_SHORT_UNSIGNED, -1,       "TileByteCounts",       NULL, NULL },
 375 { 0x014a, EXIF_FORMAT_LONG_UNSIGNED, -1,        "SubIFDs",              NULL, NULL },
 376 { 0x015b, EXIF_FORMAT_UNDEFINED, -1,            "JPEGTables",           NULL, NULL },
 377 { 0x828d, EXIF_FORMAT_SHORT_UNSIGNED, 2,        "CFARepeatPatternDim",  NULL, NULL },
 378 { 0x828e, EXIF_FORMAT_BYTE_UNSIGNED, -1,        "CFAPattern",           NULL, NULL },
 379 { 0x828f, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "BatteryLevel",         NULL, NULL },
 380 { 0x83bb, EXIF_FORMAT_LONG_UNSIGNED, -1,        "IPTC/NAA",             NULL, NULL },
 381 { 0x8773, EXIF_FORMAT_UNDEFINED, -1,            "InterColorProfile",    NULL, NULL },
 382 { 0x8825, EXIF_FORMAT_LONG_UNSIGNED, 1,         "GPSInfo",              "SubIFD GPS offset", NULL },
 383 { 0x8829, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "Interlace",            NULL, NULL },
 384 { 0x882a, EXIF_FORMAT_SHORT, 1,                 "TimeZoneOffset",       NULL, NULL },
 385 { 0x882b, EXIF_FORMAT_SHORT_UNSIGNED, 1,        "SelfTimerMode",        NULL, NULL },
 386 { 0x920b, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "FlashEnergy",          NULL, NULL },
 387 { 0x920c, EXIF_FORMAT_UNDEFINED, -1,            "SpatialFrequencyResponse", NULL, NULL },
 388 { 0x920d, EXIF_FORMAT_UNDEFINED, -1,            "Noise",                NULL, NULL },
 389 { 0x9211, EXIF_FORMAT_LONG_UNSIGNED, 1,         "ImageNumber",          NULL, NULL },
 390 { 0x9212, EXIF_FORMAT_STRING, 1,                "SecurityClassification", NULL, NULL },
 391 { 0x9213, EXIF_FORMAT_STRING, -1,               "ImageHistory",         NULL, NULL },
 392 { 0x9215, EXIF_FORMAT_RATIONAL_UNSIGNED, 1,     "ExposureIndex",        NULL, NULL },
 393 { 0x9216, EXIF_FORMAT_BYTE_UNSIGNED, 4,         "TIFF/EPStandardID",    NULL, NULL },
 394
 395         /* end is marked by 0 tag */
 396 { 0x0000, EXIF_FORMAT_UNKNOWN, 0, NULL, NULL, NULL }
 397 };
 398
 399 ExifMarker ExifUnknownMarkersList[] = {
 400 { 0x0000, EXIF_FORMAT_UNKNOWN, 0,               "unknown",      NULL, NULL },
 401 { 0x0000, EXIF_FORMAT_BYTE_UNSIGNED, -1,        "unknown",      NULL, NULL },
 402 { 0x0000, EXIF_FORMAT_STRING, -1,               "unknown",      NULL, NULL },
 403 { 0x0000, EXIF_FORMAT_SHORT_UNSIGNED, -1,       "unknown",      NULL, NULL },
 404 { 0x0000, EXIF_FORMAT_LONG_UNSIGNED, -1,        "unknown",      NULL, NULL },
 405 { 0x0000, EXIF_FORMAT_RATIONAL_UNSIGNED, -1,    "unknown",      NULL, NULL },
 406 { 0x0000, EXIF_FORMAT_BYTE, -1,                 "unknown",      NULL, NULL },
 407 { 0x0000, EXIF_FORMAT_UNDEFINED, -1,            "unknown",      NULL, NULL },
 408 { 0x0000, EXIF_FORMAT_SHORT, -1,                "unknown",      NULL, NULL },
 409 { 0x0000, EXIF_FORMAT_LONG, -1,                 "unknown",      NULL, NULL },
 410 { 0x0000, EXIF_FORMAT_RATIONAL, -1,             "unknown",      NULL, NULL },
 411 { 0x0000, EXIF_FORMAT_FLOAT, -1,                "unknown",      NULL, NULL },
 412 { 0x0000, EXIF_FORMAT_DOUBLE, -1,               "unknown",      NULL, NULL },
 413 };
 414
 415 /* human readable key list */
 416
 417 ExifFormattedText ExifFormattedList[] = {
 418         { "fCamera",            N_("Camera") },
 419         { "fDateTime",          N_("Date") },
 420         { "fShutterSpeed",      N_("Shutter speed") },
 421         { "fAperture",          N_("Aperture") },
 422         { "fExposureBias",      N_("Exposure bias") },
 423         { "fISOSpeedRating",    N_("ISO sensitivity") },
 424         { "fFocalLength",       N_("Focal length") },
 425         { "fSubjectDistance",   N_("Subject distance") },
 426         { "fFlash",             N_("Flash") },
 427         { "fResolution",        N_("Resolution") },
 428         { NULL, NULL }
 429 };
 430
 431
 432 /*
 433  *-----------------------------------------------------------------------------
 434  * misc
 435  *-----------------------------------------------------------------------------
 436  */
 437
 438 #define BYTE_ORDER_INTEL        1
 439 #define BYTE_ORDER_MOTOROLA     2
 440
 441 #define MARKER_UNKNOWN          0x00
 442 #define MARKER_SOI              0xD8
 443 #define MARKER_APP1             0xE1
 444
 445 typedef struct {
 446         char            byte_order[2];
 447         uint16_t        magic;
 448         uint32_t        IFD_offset;
 449 } TIFFHeader;
 450
 451 typedef struct {
 452         uint16_t        tag;
 453         uint16_t        format;
 454         uint32_t        nb;
 455         uint32_t        data;
 456 } IFDEntry;
 457
 458
 459 static ExifMarker *exif_marker_from_tag(uint16_t tag);
 460 static int parse_IFD_table(ExifData *exif, unsigned char *tiff, int offset,
 461                            int size, int byte_order);
 462
 463 /*
 464  *-----------------------------------------------------------------------------
 465  * ExifItem
 466  *-----------------------------------------------------------------------------
 467  */
 468
 469 static ExifItem *exif_item_new(ExifFormatType format, unsigned int tag, unsigned int elements, ExifMarker *marker)
 470 {
 471         ExifItem *item;
 472
 473         item = g_new0(ExifItem, 1);
 474         item->format = format;
 475         item->tag = tag;
 476         item->marker = marker;
 477         item->elements = elements;
 478         item->data = NULL;
 479         item->data_len = 0;
 480
 481         switch (format)
 482                 {
 483                 case EXIF_FORMAT_UNKNOWN:
 484                         /* unknown, data is NULL */
 485                         return item;
 486                         break;
 487                 case EXIF_FORMAT_BYTE_UNSIGNED:
 488                         item->data_len = sizeof(char) * elements;
 489                         break;
 490                 case EXIF_FORMAT_STRING:
 491                         item->data_len = sizeof(char) * elements;
 492                         break;
 493                 case EXIF_FORMAT_SHORT_UNSIGNED:
 494                         item->data_len = sizeof(unsigned short int) * elements;
 495                         break;
 496                 case EXIF_FORMAT_LONG_UNSIGNED:
 497                         item->data_len = sizeof(unsigned long int) * elements;
 498                         break;
 499                 case EXIF_FORMAT_RATIONAL_UNSIGNED:
 500                         item->data_len = sizeof(ExifRational) * elements;
 501                         break;
 502                 case EXIF_FORMAT_BYTE:
 503                         item->data_len = sizeof(char) * elements;
 504                         break;
 505                 case EXIF_FORMAT_UNDEFINED:
 506                         item->data_len = sizeof(char) * elements;
 507                         break;
 508                 case EXIF_FORMAT_SHORT:
 509                         item->data_len = sizeof(short int) * elements;
 510                         break;
 511                 case EXIF_FORMAT_LONG:
 512                         item->data_len = sizeof(long int) * elements;
 513                         break;
 514                 case EXIF_FORMAT_RATIONAL:
 515                         item->data_len = sizeof(ExifRational) * elements;
 516                         break;
 517                 case EXIF_FORMAT_FLOAT:
 518                         item->data_len = sizeof(float) * elements;
 519                         break;
 520                 case EXIF_FORMAT_DOUBLE:
 521                         item->data_len = sizeof(double) * elements;
 522                         break;
 523                 }
 524
 525         item->data = g_malloc0(item->data_len);
 526
 527         return item;
 528 }
 529
 530 static void exif_item_free(ExifItem *item)
 531 {
 532         if (!item) return;
 533
 534         g_free(item->data);
 535         g_free(item);
 536 }
 537
 538 const char *exif_item_get_tag_name(ExifItem *item)
 539 {
 540         if (!item || !item->marker) return NULL;
 541         return item->marker->key;
 542 }
 543
 544 const char *exif_item_get_description(ExifItem *item)
 545 {
 546         if (!item || !item->marker) return NULL;
 547         return _(item->marker->description);
 548 }
 549
 550 const char *exif_item_get_format_name(ExifItem *item, gint brief)
 551 {
 552         if (!item || !item->marker) return NULL;
 553         return (brief) ? ExifFormatList[item->format].short_name : ExifFormatList[item->format].description;
 554 }
 555
 556
 557 #define UNDEFINED_TEXT_BYTE_COUNT 16
 558
 559 static GString *string_append_raw_bytes(GString *string, gpointer data, gint ne)
 560 {
 561         gint i;
 562
 563         for (i = 0 ; i < ne && i < UNDEFINED_TEXT_BYTE_COUNT; i++)
 564                 {
 565                 unsigned char c = ((char *)data)[i];
 566                 if (c < 32 || c > 127) c = '.';
 567                 g_string_append_printf(string, "%c", c);
 568                 }
 569         string = g_string_append(string, " : ");
 570         for (i = 0 ; i < ne && i < UNDEFINED_TEXT_BYTE_COUNT; i++)
 571                 {
 572                 const gchar *spacer;
 573                 if (i > 0)
 574                         {
 575                         if (i%8 == 0)
 576                                 {
 577                                 spacer = " - ";
 578                                 }
 579                         else
 580                                 {
 581                                 spacer = " ";
 582                                 }
 583                         }
 584                 else
 585                         {
 586                         spacer = "";
 587                         }
 588                 g_string_append_printf(string, "%s%02x", spacer, ((char *)data)[i]);
 589                 }
 590         if (i >= UNDEFINED_TEXT_BYTE_COUNT) g_string_append_printf(string, " (%d bytes)", ne);
 591
 592         return string;
 593 }
 594
 595 static gchar *text_list_find_value(ExifTextList *list, gint value)
 596 {
 597         gchar *result = NULL;
 598         gint i;
 599
 600         i = 0;
 601         while (!result && list[i].value >= 0)
 602                 {
 603                 if (value == list[i].value) result = g_strdup(_(list[i].description));
 604                 i++;
 605                 }
 606         if (!result) result = g_strdup_printf("%d (%s)", value, _("unknown"));
 607
 608         return result;
 609 }
 610
 611 /*
 612  *-------------------------------------------------------------------
 613  * byte size utils
 614  *-------------------------------------------------------------------
 615  */
 616
 617 static uint16_t get_int16(unsigned char *f, int bo)
 618 {
 619         if (bo == BYTE_ORDER_INTEL)
 620                 return *f + (*(f+1)<<8);
 621         else
 622                 return ((*f)<<8) + *(f+1);
 623 }
 624
 625 #if 0
 626 /* not used ? */
 627 static uint32_t get_int32(unsigned char *f, int bo)
 628 {
 629         if (bo == BYTE_ORDER_INTEL)
 630                 return get_int16(f, BYTE_ORDER_INTEL) + (get_int16(f+2, BYTE_ORDER_INTEL)<<16);
 631         else
 632                 return (get_int16(f, BYTE_ORDER_MOTOROLA)<<16) + get_int16(f+2, BYTE_ORDER_MOTOROLA);
 633 }
 634 #endif
 635
 636 static uint16_t swab_int16(uint16_t n, int bo)
 637 {
 638 #if BYTE_ORDER == LITTLE_ENDIAN
 639         if (bo == BYTE_ORDER_MOTOROLA)
 640 #else
 641         if (bo == BYTE_ORDER_INTEL)
 642 #endif
 643                 return n>>8 | n<<8 ;
 644         else
 645                 return n;
 646 }
 647
 648 static uint32_t swab_int32(uint32_t n, int bo)
 649 {
 650 #if BYTE_ORDER == LITTLE_ENDIAN
 651         if (bo == BYTE_ORDER_MOTOROLA)
 652 #else
 653         if (bo == BYTE_ORDER_INTEL)
 654 #endif
 655                 return n<<24 | n>>24 | (n & 0xFF0000)>>8 | (n & 0xFF00)<<8;
 656         else
 657                 return n;
 658 }
 659
 660 /*
 661  *-------------------------------------------------------------------
 662  * marker utils
 663  *-------------------------------------------------------------------
 664  */
 665
 666 static int get_marker_size(unsigned char *f)
 667 {
 668         /* Size is always in Motorola byte order */
 669         return get_int16(f+2, BYTE_ORDER_MOTOROLA);
 670 }
 671
 672 static int goto_next_marker(unsigned char **f, int *size, int *marker)
 673 {
 674         int marker_size = 2;
 675
 676         *marker = MARKER_UNKNOWN;
 677
 678         /* It is safe to access the marker and its size since we have checked
 679          * the SOI and this function guaranties the whole next marker is
 680          * available
 681          */
 682         if (*(*f+1) != MARKER_SOI)
 683                 {
 684                 marker_size += get_marker_size(*f);
 685                 }
 686
 687         *size -= marker_size;
 688
 689         /* size should be at least 4, so we can read the marker and its size
 690          * and check data are actually available
 691          */
 692         if (*size < 4) return -1;
 693
 694         /* Jump to the next marker and be sure it begins with 0xFF
 695          */
 696         *f += marker_size;
 697         if (**f != 0xFF) return -1;
 698
 699         if (get_marker_size(*f)+2 > *size) return -1;
 700
 701         *marker = *(*f+1);
 702
 703         return 0;
 704 }
 705
 706 /*
 707  *-------------------------------------------------------------------
 708  * IFD utils
 709  *-------------------------------------------------------------------
 710  */
 711
 712 static ExifMarker *exif_marker_from_tag(uint16_t tag)
 713 {
 714         static int len = sizeof(ExifKnownMarkersList)/sizeof(ExifMarker) - 1;
 715         int i = 0;
 716
 717         while (i < len && ExifKnownMarkersList[i].tag != tag)
 718                 {
 719                 i++;
 720                 }
 721
 722         return (i >= len ? NULL : &ExifKnownMarkersList[i]);
 723 }
 724
 725 static void rational_from_data(ExifRational *r, void *src, int byte_order)
 726 {
 727         r->num = swab_int32(*(uint32_t*)src, byte_order);
 728         r->den = swab_int32(*(uint32_t*)(src + sizeof(uint32_t)), byte_order);
 729 }
 730
 731 static void exif_item_copy_data(ExifItem *item, void *src, int len, ExifFormatType src_format, int byte_order)
 732 {
 733         int bs;
 734         int ne;
 735         gpointer dest;
 736         int i;
 737
 738         bs = ExifFormatList[item->format].size;
 739         ne = item->elements;
 740         dest = item->data;
 741
 742         if (!dest || len > item->data_len)
 743                 {
 744                 printf("exif tag %s data size mismatch\n", exif_item_get_tag_name(item));
 745                 return;
 746                 }
 747
 748         switch (item->format)
 749                 {
 750                 case EXIF_FORMAT_UNKNOWN:
 751                         break;
 752                 case EXIF_FORMAT_BYTE_UNSIGNED:
 753                 case EXIF_FORMAT_BYTE:
 754                 case EXIF_FORMAT_UNDEFINED:
 755                         memcpy(dest, src, len);
 756                         break;
 757                 case EXIF_FORMAT_STRING:
 758                         memcpy(dest, src, len);
 759                         /* string is NULL terminated, make sure this is true */
 760                         if (((char *)dest)[len - 1] != '\0') ((char *)dest)[len - 1] = '\0';
 761                         break;
 762                 case EXIF_FORMAT_SHORT_UNSIGNED:
 763                 case EXIF_FORMAT_SHORT:
 764                         for (i = 0; i < ne; i++)
 765                                 {
 766                                 ((short *)dest)[i] = swab_int16(*(uint16_t*)(src + i * bs), byte_order);
 767                                 }
 768                         break;
 769                 case EXIF_FORMAT_LONG_UNSIGNED:
 770                 case EXIF_FORMAT_LONG:
 771                         if (src_format == EXIF_FORMAT_SHORT_UNSIGNED ||
 772                             src_format == EXIF_FORMAT_SHORT)
 773                                 {
 774                                 /* a short fits into a long, so allow it */
 775                                 int ss;
 776
 777                                 ss = ExifFormatList[src_format].size;
 778                                 for (i = 0; i < ne; i++)
 779                                         {
 780                                         ((long *)dest)[i] = (long)swab_int16(*(uint16_t*)(src + i * ss), byte_order);
 781                                         }
 782                                 }
 783                         else
 784                                 {
 785                                 for (i = 0; i < ne; i++)
 786                                         {
 787                                         ((long *)dest)[i] = swab_int32(*(uint32_t*)(src + i * bs), byte_order);
 788                                         }
 789                                 }
 790                         break;
 791                 case EXIF_FORMAT_RATIONAL_UNSIGNED:
 792                 case EXIF_FORMAT_RATIONAL:
 793                         for (i = 0; i < ne; i++)
 794                                 {
 795                                 rational_from_data(&((ExifRational *)dest)[i], src + i * bs, byte_order);
 796                                 }
 797                         break;
 798                 case EXIF_FORMAT_FLOAT:
 799                         for (i = 0; i < ne; i++)
 800                                 {
 801                                 ((float *)dest)[i] = swab_int32(*(uint32_t*)(src + i * bs), byte_order);
 802                                 }
 803                         break;
 804                 case EXIF_FORMAT_DOUBLE:
 805                         for (i = 0; i < ne; i++)
 806                                 {
 807                                 ExifRational r;
 808
 809                                 rational_from_data(&r, src + i * bs, byte_order);
 810                                 if (r.den) ((double *)dest)[i] = (double)r.num / r.den;
 811                                 }
 812                         break;
 813                 }
 814 }
 815
 816 static int parse_IFD_entry(ExifData *exif, unsigned char *tiff, int offset,
 817                            int size, int byte_order)
 818 {
 819         IFDEntry *ent = (IFDEntry*)(tiff+offset);
 820         uint32_t swabed_data;
 821         void *data;
 822         int data_len;
 823         ExifMarker *marker;
 824         ExifItem *item;
 825
 826         ent->tag = swab_int16(ent->tag, byte_order);
 827         ent->format = swab_int16(ent->format, byte_order);
 828         ent->nb = swab_int32(ent->nb, byte_order);
 829         swabed_data = swab_int32(ent->data, byte_order);
 830
 831         /* Check tag type. If it does not match, either the format is wrong,
 832          * either it is a unknown tag; so it is not really an error.
 833          */
 834         marker = exif_marker_from_tag(ent->tag);
 835         if (!marker)
 836                 {
 837                 if (ent->format > EXIF_FORMAT_DOUBLE)
 838                         {
 839                         printf("warning: exif tag 0x%4x has invalid format %d\n", ent->tag, ent->format);
 840                         return 0;
 841                         }
 842                 /* allow non recognized tags to be displayed */
 843                 marker = &ExifUnknownMarkersList[ent->format];
 844                 }
 845         if (marker->format != ent->format)
 846                 {
 847                 /* Some cameras got mixed up signed/unsigned_rational
 848                  * eg KODAK DC4800 on object_distance tag
 849                  *
 850                  * FIXME: what exactly is this test trying to do?
 851                  * ok, so this test is to allow the case of swapped signed/unsigned mismatch to leak through?
 852                  */
 853                 if ( !(marker->format == EXIF_FORMAT_RATIONAL_UNSIGNED && ent->format == EXIF_FORMAT_RATIONAL) &&
 854                      !(marker->format == EXIF_FORMAT_RATIONAL && ent->format == EXIF_FORMAT_RATIONAL_UNSIGNED) &&
 855                         /* short fits into a long so allow this mismatch
 856                          * as well (some tags allowed to be unsigned short _or_ unsigned long)
 857                          */
 858                      !(marker->format == EXIF_FORMAT_LONG_UNSIGNED && ent->format == EXIF_FORMAT_SHORT_UNSIGNED) )
 859                         {
 860                         if (ent->format <= EXIF_FORMAT_DOUBLE)
 861                                 {
 862                                 printf("warning: exif tag %s format mismatch, found %s exif spec requests %s\n",
 863                                         marker->key, ExifFormatList[ent->format].short_name, ExifFormatList[marker->format].short_name);
 864                                 }
 865                         else
 866                                 {
 867                                 printf("warning: exif tag %s format mismatch, found unknown id %d exif spec requests %d (%s)\n",
 868                                         marker->key, ent->format, marker->format, ExifFormatList[marker->format].short_name);
 869                                 }
 870                         return 0;
 871                         }
 872                 }
 873
 874         /* Where is the data, is it available?
 875          */
 876         if (marker->components > 0 && marker->components != ent->nb)
 877                 {
 878                 printf("warning: exif tag %s has %d elements, exif spec requests %d\n", marker->key, ent->nb, marker->components);
 879                 }
 880         data_len = ExifFormatList[marker->format].size * ent->nb;
 881         if (data_len > sizeof(ent->data))
 882                 {
 883                 if (size < swabed_data+data_len)
 884                         {
 885                         printf("warning: exif tag %s will overrun IFD segment, ignored.\n", marker->key);
 886                         return -1;
 887                         }
 888                 data = (void*)tiff + swabed_data;
 889                 }
 890         else
 891                 {
 892                 data = (void*)(&(ent->data));
 893                 }
 894
 895         item = exif_item_new(marker->format, ent->tag, ent->nb, marker);
 896         exif_item_copy_data(item, data, data_len, ent->format, byte_order);
 897         exif->items = g_list_prepend(exif->items, item);
 898
 899         if (item->tag == TAG_EXIFOFFSET)
 900                 {
 901                 parse_IFD_table(exif, tiff, swabed_data, size, byte_order);
 902                 }
 903
 904         return 0;
 905 }
 906
 907 static int parse_IFD_table(ExifData *exif, unsigned char *tiff, int offset,
 908                            int size, int byte_order)
 909 {
 910         int i, nb_entries;
 911
 912         /* We should be able to read number of entries in IFD0) */
 913         if (size < offset+2) return -1;
 914
 915         nb_entries = get_int16(tiff+offset, byte_order);
 916
 917         /* Entries and next IFD offset must be readable */
 918         if (size < offset+nb_entries*12+4) return -1;
 919
 920         for (i=0; i<nb_entries; ++i)
 921                 {
 922                 parse_IFD_entry(exif, tiff, offset+2+i*sizeof(IFDEntry), size, byte_order);
 923                 }
 924
 925         return 0;
 926 }
 927
 928 /*
 929  *-------------------------------------------------------------------
 930  * file formats
 931  *-------------------------------------------------------------------
 932  */
 933
 934 static int parse_TIFF(ExifData *exif, unsigned char *tiff, int size)
 935 {
 936         int byte_order, offset=0;
 937
 938         if (size < sizeof(TIFFHeader))
 939                 {
 940                 return -1;
 941                 }
 942
 943         if (strncmp(((TIFFHeader*)tiff)->byte_order, "II", 2) == 0)
 944                 {
 945                 byte_order = BYTE_ORDER_INTEL;
 946                 }
 947         else if (strncmp(((TIFFHeader*)tiff)->byte_order, "MM", 2) == 0)
 948                 {
 949                 byte_order = BYTE_ORDER_MOTOROLA;
 950                 }
 951         else
 952                 {
 953                 return -1;
 954                 }
 955
 956         if (swab_int16(((TIFFHeader*)tiff)->magic, byte_order) != 0x002A)
 957                 {
 958                 return -1;
 959                 }
 960
 961         offset = swab_int32(((TIFFHeader*)tiff)->IFD_offset, byte_order);
 962
 963         return parse_IFD_table(exif, tiff, offset, size, byte_order);
 964 }
 965
 966 static int parse_JPEG(ExifData *exif, unsigned char *f, int size)
 967 {
 968         int marker, marker_size;
 969
 970         if (size<2 || *f!=0xFF || *(f+1)!=MARKER_SOI)
 971                 {
 972                 return -2;
 973                 }
 974
 975         do {
 976                 if (goto_next_marker(&f, &size, &marker) == -1)
 977                         {
 978                         break;
 979                         }
 980         } while (marker != MARKER_APP1);
 981
 982         if (marker != MARKER_APP1)
 983                 {
 984                 return -2;
 985                 }
 986
 987         marker_size = get_marker_size(f)-2;
 988
 989         if (marker_size<6 || strncmp((char*)f+4, "Exif\0\0", 6)!=0)
 990                 {
 991                 return -2;
 992                 }
 993
 994         return parse_TIFF(exif, f+10, marker_size-6);
 995 }
 996
 997 static gint map_file(const gchar *path, void **mapping, int *size)
 998 {
 999         int fd;
1000         struct stat fs;
1001
1002         if ((fd = open(path, O_RDONLY)) == -1)
1003                 {
1004                 perror(path);
1005                 return -1;
1006                 }
1007
1008         if (fstat(fd, &fs) == -1)
1009                 {
1010                 perror(path);
1011                 close(fd);
1012                 return -1;
1013                 }
1014
1015         *size = fs.st_size;
1016
1017         if ((*mapping = mmap(0, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0)) == MAP_FAILED)
1018                 {
1019                 perror(path);
1020                 close(fd);
1021                 return -1;
1022                 }
1023
1024         close(fd);
1025         return 0;
1026 }
1027
1028 static gint unmap_file(void *mapping, int size)
1029 {
1030         if (munmap(mapping, size) == -1)
1031                 {
1032                 perror("munmap");
1033                 return -1;
1034                 }
1035
1036         return 0;
1037 }
1038
1039 void exif_free(ExifData *exif)
1040 {
1041         GList *work;
1042
1043         if (!exif) return;
1044
1045         work = exif->items;
1046         while (work)
1047                 {
1048                 ExifItem *item = work->data;
1049                 work = work->next;
1050                 exif_item_free(item);
1051                 }
1052
1053         g_list_free(exif->items);
1054         g_free(exif);
1055 }
1056
1057 ExifData *exif_read(const gchar *path)
1058 {
1059         ExifData *exif;
1060         void *f;
1061         int size, res;
1062         gchar *pathl;
1063
1064         if (!path) return NULL;
1065
1066         pathl = path_from_utf8(path);
1067         if (map_file(pathl, &f, &size) == -1)
1068                 {
1069                 g_free(pathl);
1070                 return NULL;
1071                 }
1072         g_free(pathl);
1073
1074         exif = g_new0(ExifData, 1);
1075         exif->items = NULL;
1076
1077         if ((res = parse_JPEG(exif, (unsigned char *)f, size)) == -2)
1078                 {
1079                 res = parse_TIFF(exif, (unsigned char *)f, size);
1080                 }
1081
1082         if (res != 0)
1083                 {
1084                 exif_free(exif);
1085                 exif = NULL;
1086                 }
1087
1088         unmap_file(f, size);
1089
1090         if (exif) exif->items = g_list_reverse(exif->items);
1091
1092 #if 0
1093         exif_write_data_list(exif, stdout, TRUE);
1094         exif_write_data_list(exif, stdout, FALSE);
1095 #endif
1096
1097         return exif;
1098 }
1099
1100 ExifItem *exif_get_item(ExifData *exif, const gchar *key)
1101 {
1102         GList *work;
1103
1104         if (!key) return NULL;
1105
1106         work = exif->items;
1107         while (work)
1108                 {
1109                 ExifItem *item;
1110
1111                 item = work->data;
1112                 work = work->next;
1113                 if (item->marker->key && strcmp(key, item->marker->key) == 0) return item;
1114                 }
1115         return NULL;
1116 }
1117
1118 gchar *exif_item_get_data_as_text(ExifItem *item)
1119 {
1120         ExifMarker *marker;
1121         gpointer data;
1122         GString *string;
1123         gchar *text;
1124         gint ne;
1125         gint i;
1126
1127         if (!item) return NULL;
1128
1129         marker = item->marker;
1130         if (!marker) return NULL;
1131
1132         data = item->data;
1133         ne = item->elements;
1134         string = g_string_new("");
1135         switch (item->format)
1136                 {
1137                 case EXIF_FORMAT_UNKNOWN:
1138                         break;
1139                 case EXIF_FORMAT_BYTE_UNSIGNED:
1140                 case EXIF_FORMAT_BYTE:
1141                 case EXIF_FORMAT_UNDEFINED:
1142                         if (ne == 1 && marker->list)
1143                                 {
1144                                 gchar *result;
1145                                 unsigned char val;
1146
1147                                 if (item->format == EXIF_FORMAT_BYTE_UNSIGNED ||
1148                                     item->format == EXIF_FORMAT_UNDEFINED)
1149                                         {
1150                                         val = ((unsigned char *)data)[0];
1151                                         }
1152                                 else
1153                                         {
1154                                         val = (unsigned char)(((signed char *)data)[0]);
1155                                         }
1156
1157                                 result = text_list_find_value(marker->list, (unsigned short)val);
1158                                 string = g_string_append(string, result);
1159                                 g_free(result);
1160                                 }
1161                         else
1162                                 {
1163                                 string = string_append_raw_bytes(string, data, ne);
1164                                 }
1165                         break;
1166                 case EXIF_FORMAT_STRING:
1167                         string = g_string_append(string, (gchar *)(item->data));
1168                         break;
1169                 case EXIF_FORMAT_SHORT_UNSIGNED:
1170                         if (ne == 1 && marker->list)
1171                                 {
1172                                 gchar *result;
1173
1174                                 result = text_list_find_value(marker->list, ((unsigned short *)data)[0]);
1175                                 string = g_string_append(string, result);
1176                                 g_free(result);
1177                                 }
1178                         else for (i = 0; i < ne; i++)
1179                                 {
1180                                 g_string_append_printf(string, "%s%hd", (i > 0) ? ", " : "",
1181                                                         ((unsigned short *)data)[i]);
1182                                 }
1183                         break;
1184                 case EXIF_FORMAT_LONG_UNSIGNED:
1185                         for (i = 0; i < ne; i++)
1186                                 {
1187                                 g_string_append_printf(string, "%s%ld", (i > 0) ? ", " : "",
1188                                                         ((unsigned long *)data)[i]);
1189                                 }
1190                         break;
1191                 case EXIF_FORMAT_RATIONAL_UNSIGNED:
1192                         for (i = 0; i < ne; i++)
1193                                 {
1194                                 ExifRational *r;
1195
1196                                 r = &((ExifRational *)data)[i];
1197                                 g_string_append_printf(string, "%s%ld/%ld", (i > 0) ? ", " : "",
1198                                                         (unsigned long)r->num, (unsigned long)r->den);
1199                                 }
1200                         break;
1201                 case EXIF_FORMAT_SHORT:
1202                         for (i = 0; i < ne; i++)
1203                                 {
1204                                 g_string_append_printf(string, "%s%hd", (i > 0) ? ", " : "",
1205                                                         ((short *)data)[i]);
1206                                 }
1207                         break;
1208                 case EXIF_FORMAT_LONG:
1209                         for (i = 0; i < ne; i++)
1210                                 {
1211                                 g_string_append_printf(string, "%s%ld", (i > 0) ? ", " : "",
1212                                                         ((long *)data)[i]);
1213                                 }
1214                         break;
1215                 case EXIF_FORMAT_RATIONAL:
1216                         for (i = 0; i < ne; i++)
1217                                 {
1218                                 ExifRational *r;
1219
1220                                 r = &((ExifRational *)data)[i];
1221                                 g_string_append_printf(string, "%s%ld/%ld", (i > 0) ? ", " : "",
1222                                                         (long)r->num, (long)r->den);
1223                                 }
1224                         break;
1225                 case EXIF_FORMAT_FLOAT:
1226                         for (i = 0; i < ne; i++)
1227                                 {
1228                                 g_string_append_printf(string, "%s%f", (i > 0) ? ", " : "",
1229                                                         ((float *)data)[i]);
1230                                 }
1231                         break;
1232                 case EXIF_FORMAT_DOUBLE:
1233                         for (i = 0; i < ne; i++)
1234                                 {
1235                                 g_string_append_printf(string, "%s%f", (i > 0) ? ", " : "",
1236                                                         ((double *)data)[i]);
1237                                 }
1238                         break;
1239                 }
1240
1241         text = g_strdup(string->str);
1242         g_string_free(string, TRUE);
1243
1244         return text;
1245 }
1246
1247 gint exif_item_get_integer(ExifItem *item, gint *value)
1248 {
1249         if (!item) return FALSE;
1250
1251         switch (item->format)
1252                 {
1253                 case EXIF_FORMAT_SHORT:
1254                         *value = (gint)(((short *)(item->data))[0]);
1255                         return TRUE;
1256                         break;
1257                 case EXIF_FORMAT_SHORT_UNSIGNED:
1258                         *value = (gint)(((unsigned short *)(item->data))[0]);
1259                         return TRUE;
1260                         break;
1261                 case EXIF_FORMAT_LONG:
1262                         *value = (gint)(((long *)(item->data))[0]);
1263                         return TRUE;
1264                         break;
1265                 case EXIF_FORMAT_LONG_UNSIGNED:
1266                         /* FIXME: overflow possible */
1267                         *value = (gint)(((unsigned long *)(item->data))[0]);
1268                         return TRUE;
1269                 default:
1270                         /* all other type return FALSE */
1271                         break;
1272                 }
1273         return FALSE;
1274 }
1275
1276 gint exif_get_integer(ExifData *exif, const gchar *key, gint *value)
1277 {
1278         ExifItem *item;
1279
1280         item = exif_get_item(exif, key);
1281         return exif_item_get_integer(item, value);
1282 }
1283
1284 ExifRational *exif_item_get_rational(ExifItem *item, gint *sign)
1285 {
1286         if (!item) return NULL;
1287
1288         if (item->format == EXIF_FORMAT_RATIONAL ||
1289             item->format == EXIF_FORMAT_RATIONAL_UNSIGNED)
1290                 {
1291                 if (sign) *sign = (item->format == EXIF_FORMAT_RATIONAL);
1292                 return &((ExifRational *)(item->data))[0];
1293                 }
1294
1295         return NULL;
1296 }
1297
1298 ExifRational *exif_get_rational(ExifData *exif, const gchar *key, gint *sign)
1299 {
1300         ExifItem *item;
1301
1302         item = exif_get_item(exif, key);
1303         return exif_item_get_rational(item, sign);
1304 }
1305
1306 double exif_rational_to_double(ExifRational *r, gint sign)
1307 {
1308         if (!r || r->den == 0.0) return 0.0;
1309
1310         if (sign) return (double)((int)r->num) / (double)((int)r->den);
1311         return (double)r->num / r->den;
1312 }
1313
1314 static double exif_get_rational_as_double(ExifData *exif, const gchar *key)
1315 {
1316         ExifRational *r;
1317         gint sign;
1318
1319         r = exif_get_rational(exif, key, &sign);
1320         return exif_rational_to_double(r, sign);
1321 }
1322
1323 static GString *append_comma_text(GString *string, const gchar *text)
1324 {
1325         string = g_string_append(string, ", ");
1326         string = g_string_append(string, text);
1327
1328         return string;
1329 }
1330
1331 static gchar *exif_get_formatted_by_key(ExifData *exif, const gchar *key, gint *key_valid)
1332 {
1333         /* must begin with f, else not formatted */
1334         if (key[0] != 'f')
1335                 {
1336                 if (key_valid) *key_valid = FALSE;
1337                 return NULL;
1338                 }
1339
1340         if (key_valid) *key_valid = TRUE;
1341
1342         if (strcmp(key, "fCamera") == 0)
1343                 {
1344                 gchar *text;
1345                 gchar *make = exif_get_data_as_text(exif, "Make");
1346                 gchar *model = exif_get_data_as_text(exif, "Model");
1347                 gchar *software = exif_get_data_as_text(exif, "Software");
1348
1349                 text = g_strdup_printf("%s%s%s%s%s%s", (make) ? make : "", ((make) && (model)) ? " " : "",
1350                                                        (model) ? model : "",
1351                                                        (software) ? " (" : "",
1352                                                        (software) ? software : "",
1353                                                        (software) ? ")" : "");
1354
1355                 g_free(make);
1356                 g_free(model);
1357                 g_free(software);
1358                 return text;
1359                 }
1360         if (strcmp(key, "fDateTime") == 0)
1361                 {
1362                 gchar *text = exif_get_data_as_text(exif, "DateTimeOriginal");
1363                 gchar *subsec = NULL;
1364                 if (text) subsec = exif_get_data_as_text(exif, "SubsecTimeOriginal");
1365                 if (!text)
1366                         {
1367                         text = exif_get_data_as_text(exif, "DateTime");
1368                         if (text) subsec = exif_get_data_as_text(exif, "SubsecTime");
1369                         }
1370                 if (subsec)
1371                         {
1372                         gchar *tmp = text;
1373                         text = g_strconcat(tmp, ".", subsec, NULL);
1374                         g_free(tmp);
1375                         g_free(subsec);
1376                         }
1377                 return text;
1378                 }
1379         if (strcmp(key, "fShutterSpeed") == 0)
1380                 {
1381                 ExifRational *r;
1382
1383                 r = exif_get_rational(exif, "ExposureTime", NULL);
1384                 if (r && r->num && r->den)
1385                         {
1386                         double n = (double)r->den / (double)r->num;
1387                         return g_strdup_printf("%s%.0fs", n > 1.0 ? "1/" : "",
1388                                                           n > 1.0 ? n : 1.0 / n);
1389                         }
1390                 r = exif_get_rational(exif, "ShutterSpeedValue", NULL);
1391                 if (r && r->num  && r->den)
1392                         {
1393                         double n = pow(2.0, exif_rational_to_double(r, TRUE));
1394
1395                         /* Correct exposure time to avoid values like 1/91s (seen on Minolta DImage 7) */
1396                         if (n > 1.0 && (int)n - ((int)(n/10))*10 == 1) n--;
1397
1398                         return g_strdup_printf("%s%.0fs", n > 1.0 ? "1/" : "",
1399                                                           n > 1.0 ? floor(n) : 1.0 / n);
1400                         }
1401                 return NULL;
1402                 }
1403         if (strcmp(key, "fAperture") == 0)
1404                 {
1405                 double n;
1406
1407                 n = exif_get_rational_as_double(exif, "FNumber");
1408                 if (n == 0.0) n = exif_get_rational_as_double(exif, "ApertureValue");
1409                 if (n == 0.0) return NULL;
1410
1411                 return g_strdup_printf("f/%.1f", n);
1412                 }
1413         if (strcmp(key, "fExposureBias") == 0)
1414                 {
1415                 ExifRational *r;
1416                 gint sign;
1417                 double n;
1418
1419                 r = exif_get_rational(exif, "ExposureBiasValue", &sign);
1420                 if (!r) return NULL;
1421
1422                 n = exif_rational_to_double(r, sign);
1423                 return g_strdup_printf("%+.1f", n);
1424                 }
1425         if (strcmp(key, "fFocalLength") == 0)
1426                 {
1427                 double n;
1428
1429                 n = exif_get_rational_as_double(exif, "FocalLength");
1430                 if (n == 0.0) return NULL;
1431                 return g_strdup_printf("%.2f mm", n);
1432                 }
1433         if (strcmp(key, "fISOSpeedRating") == 0)
1434                 {
1435                 gchar *text;
1436
1437                 text = exif_get_data_as_text(exif, "ISOSpeedRatings");
1438                 /* kodak may set this instead */
1439                 if (!text) text = exif_get_data_as_text(exif, "ExposureIndex");
1440                 return text;
1441                 }
1442         if (strcmp(key, "fSubjectDistance") == 0)
1443                 {
1444                 ExifRational *r;
1445                 gint sign;
1446                 double n;
1447
1448                 r = exif_get_rational(exif, "SubjectDistance", &sign);
1449                 if (!r) return NULL;
1450
1451                 if ((long)r->num == 0xffffffff) return g_strdup(_("infinity"));
1452                 if ((long)r->num == 0) return g_strdup(_("unknown"));
1453
1454                 n = exif_rational_to_double(r, sign);
1455                 if (n == 0.0) return _("unknown");
1456                 return g_strdup_printf("%.3f m", n);
1457                 }
1458         if (strcmp(key, "fFlash") == 0)
1459                 {
1460                 /* grr, flash is a bitmask... */
1461                 GString *string;
1462                 gchar *text;
1463                 gint n;
1464                 gint v;
1465
1466                 if (!exif_get_integer(exif, "Flash", &n)) return NULL;
1467
1468                 /* Exif 2.1 only defines first 3 bits */
1469                 if (n <= 0x07) return g_strdup(text_list_find_value(ExifFlashList, n));
1470
1471                 /* must be Exif 2.2 */
1472                 string = g_string_new("");
1473
1474                 /* flash fired (bit 0) */
1475                 string = g_string_append(string, (n & 0x01) ? _("yes") : _("no"));
1476
1477                 /* flash mode (bits 3, 4) */
1478                 v = (n >> 3) & 0x03;
1479                 if (v) string = append_comma_text(string, _("mode:"));
1480                 switch (v)
1481                         {
1482                         case 1:
1483                                 string = g_string_append(string, _("on"));
1484                                 break;
1485                         case 2:
1486                                 string = g_string_append(string, _("off"));
1487                                 break;
1488                         case 3:
1489                                 string = g_string_append(string, _("auto"));
1490                                 break;
1491                         }
1492
1493                 /* return light (bits 1, 2) */
1494                 v = (n >> 1) & 0x03;
1495                 if (v == 2) string = append_comma_text(string, _("not detected by strobe"));
1496                 if (v == 3) string = append_comma_text(string, _("detected by strobe"));
1497
1498                 /* we ignore flash function (bit 5) */
1499
1500                 /* red-eye (bit 6) */
1501                 if ((n >> 5) & 0x01) string = append_comma_text(string, _("red-eye reduction"));
1502
1503                 text = string->str;
1504                 g_string_free(string, FALSE);
1505                 return text;
1506                 }
1507         if (strcmp(key, "fResolution") == 0)
1508                 {
1509                 ExifRational *rx, *ry;
1510                 gchar *units;
1511                 gchar *text;
1512
1513                 rx = exif_get_rational(exif, "XResolution", NULL);
1514                 ry = exif_get_rational(exif, "YResolution", NULL);
1515                 if (!rx || !ry) return NULL;
1516
1517                 units = exif_get_data_as_text(exif, "ResolutionUnit");
1518                 text = g_strdup_printf("%0.f x %0.f (%s/%s)", rx->den ? (double)rx->num / rx->den : 1.0,
1519                                                               ry->den ? (double)ry->num / ry->den : 1.0,
1520                                                               _("dot"), (units) ? units : _("unknown"));
1521
1522                 g_free(units);
1523                 return text;
1524                 }
1525
1526         if (key_valid) *key_valid = FALSE;
1527         return NULL;
1528 }
1529
1530 gchar *exif_get_data_as_text(ExifData *exif, const gchar *key)
1531 {
1532         ExifItem *item;
1533         gchar *text;
1534         gint key_valid;
1535
1536         if (!key) return NULL;
1537
1538         text = exif_get_formatted_by_key(exif, key, &key_valid);
1539         if (key_valid) return text;
1540
1541         item = exif_get_item(exif, key);
1542         if (item) return exif_item_get_data_as_text(item);
1543
1544         return NULL;
1545 }
1546
1547 const gchar *exif_get_description_by_key(const gchar *key)
1548 {
1549         gint i;
1550
1551         if (!key) return NULL;
1552
1553         i = 0;
1554         while (ExifFormattedList[i].key != NULL)
1555                 {
1556                 if (strcmp(key, ExifFormattedList[i].key) == 0) return _(ExifFormattedList[i].description);
1557                 i++;
1558                 }
1559
1560         i = 0;
1561         while (ExifKnownMarkersList[i].tag > 0)
1562                 {
1563                 if (strcmp(key, ExifKnownMarkersList[i].key) == 0) return _(ExifKnownMarkersList[i].description);
1564                 i++;
1565                 }
1566
1567         return NULL;
1568 }
1569
1570 static void exif_write_item(FILE *f, ExifItem *item)
1571 {
1572         gchar *text;
1573
1574         text = exif_item_get_data_as_text(item);
1575         if (text)
1576                 {
1577                 fprintf(f, "%4x %9s %30s %s\n", item->tag, ExifFormatList[item->format].short_name,
1578                         exif_item_get_tag_name(item), text);
1579                 }
1580         g_free(text);
1581 }
1582
1583 void exif_write_data_list(ExifData *exif, FILE *f, gint human_readable_list)
1584 {
1585         if (!f || !exif) return;
1586
1587         fprintf(f, " tag   format                             key value\n");
1588         fprintf(f, "----------------------------------------------------\n");
1589
1590         if (human_readable_list)
1591                 {
1592                 gint i;
1593
1594                 i = 0;
1595                 while (ExifFormattedList[i].key)
1596                         {
1597                         gchar *text;
1598
1599                         text = exif_get_formatted_by_key(exif, ExifFormattedList[i].key, NULL);
1600                         if (text)
1601                                 {
1602                                 fprintf(f, "     %9s %30s %s\n", "string", ExifFormattedList[i].key, text);
1603                                 }
1604                         i++;
1605                         }
1606                 }
1607         else
1608                 {
1609                 GList *work;
1610
1611                 work = exif->items;
1612                 while (work)
1613                         {
1614                         ExifItem *item;
1615
1616                         item = work->data;
1617                         work = work->next;
1618
1619                         exif_write_item(f, item);
1620                         }
1621                 }
1622         fprintf(f, "----------------------------------------------------\n");
1623 }
1624