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- # Library to extract EXIF information in digital camera image files
- #
- # Contains code from "exifdump.py" originally written by Thierry Bousch
- # <bousch@topo.math.u-psud.fr> and released into the public domain.
- #
- # Updated and turned into general-purpose library by Gene Cash
- # <email gcash at cfl.rr.com>
- #
- # This copyright license is intended to be similar to the FreeBSD license.
- #
- # Copyright 2002 Gene Cash All rights reserved.
- #
- # Redistribution and use in source and binary forms, with or without
- # modification, are permitted provided that the following conditions are
- # met:
- #
- # 1. Redistributions of source code must retain the above copyright
- # notice, this list of conditions and the following disclaimer.
- # 2. Redistributions in binary form must reproduce the above copyright
- # notice, this list of conditions and the following disclaimer in the
- # documentation and/or other materials provided with the
- # distribution.
- #
- # THIS SOFTWARE IS PROVIDED BY GENE CASH ``AS IS'' AND ANY EXPRESS OR
- # IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- # OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- # DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
- # ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- # STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- # ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- # POSSIBILITY OF SUCH DAMAGE.
- #
- # This means you may do anything you want with this code, except claim you
- # wrote it. Also, if it breaks you get to keep both pieces.
- #
- # 21-AUG-99 TB Last update by Thierry Bousch to his code.
- # 17-JAN-02 CEC Discovered code on web.
- # Commented everything.
- # Made small code improvements.
- # Reformatted for readability.
- # 19-JAN-02 CEC Added ability to read TIFFs and JFIF-format JPEGs.
- # Added ability to extract JPEG formatted thumbnail.
- # Added ability to read GPS IFD (not tested).
- # Converted IFD data structure to dictionaries indexed by
- # tag name.
- # Factored into library returning dictionary of IFDs plus
- # thumbnail, if any.
- # 20-JAN-02 CEC Added MakerNote processing logic.
- # Added Olympus MakerNote.
- # Converted data structure to single-level dictionary, avoiding
- # tag name collisions by prefixing with IFD name. This makes
- # it much easier to use.
- # 23-JAN-02 CEC Trimmed nulls from end of string values.
- # 25-JAN-02 CEC Discovered JPEG thumbnail in Olympus TIFF MakerNote.
- # 26-JAN-02 CEC Added ability to extract TIFF thumbnails.
- # Added Nikon, Fujifilm, Casio MakerNotes.
- # 30-NOV-03 CEC Fixed problem with canon_decode_tag() not creating an
- # IFD_Tag() object.
- # 15-FEB-04 CEC Finally fixed bit shift warning by converting Y to 0L.
- #
- # To do:
- # * Better printing of ratios
-
- # field type descriptions as (length, abbreviation, full name) tuples
- FIELD_TYPES=(
- (0, 'X', 'Proprietary'), # no such type
- (1, 'B', 'Byte'),
- (1, 'A', 'ASCII'),
- (2, 'S', 'Short'),
- (4, 'L', 'Long'),
- (8, 'R', 'Ratio'),
- (1, 'SB', 'Signed Byte'),
- (1, 'U', 'Undefined'),
- (2, 'SS', 'Signed Short'),
- (4, 'SL', 'Signed Long'),
- (8, 'SR', 'Signed Ratio')
- )
-
- # dictionary of main EXIF tag names
- # first element of tuple is tag name, optional second element is
- # another dictionary giving names to values
- EXIF_TAGS={
- 0x0100: ('ImageWidth', ),
- 0x0101: ('ImageLength', ),
- 0x0102: ('BitsPerSample', ),
- 0x0103: ('Compression',
- {1: 'Uncompressed TIFF',
- 6: 'JPEG Compressed'}),
- 0x0106: ('PhotometricInterpretation', ),
- 0x010A: ('FillOrder', ),
- 0x010D: ('DocumentName', ),
- 0x010E: ('ImageDescription', ),
- 0x010F: ('Make', ),
- 0x0110: ('Model', ),
- 0x0111: ('StripOffsets', ),
- 0x0112: ('Orientation', ),
- 0x0115: ('SamplesPerPixel', ),
- 0x0116: ('RowsPerStrip', ),
- 0x0117: ('StripByteCounts', ),
- 0x011A: ('XResolution', ),
- 0x011B: ('YResolution', ),
- 0x011C: ('PlanarConfiguration', ),
- 0x0128: ('ResolutionUnit',
- {1: 'Not Absolute',
- 2: 'Pixels/Inch',
- 3: 'Pixels/Centimeter'}),
- 0x012D: ('TransferFunction', ),
- 0x0131: ('Software', ),
- 0x0132: ('DateTime', ),
- 0x013B: ('Artist', ),
- 0x013E: ('WhitePoint', ),
- 0x013F: ('PrimaryChromaticities', ),
- 0x0156: ('TransferRange', ),
- 0x0200: ('JPEGProc', ),
- 0x0201: ('JPEGInterchangeFormat', ),
- 0x0202: ('JPEGInterchangeFormatLength', ),
- 0x0211: ('YCbCrCoefficients', ),
- 0x0212: ('YCbCrSubSampling', ),
- 0x0213: ('YCbCrPositioning', ),
- 0x0214: ('ReferenceBlackWhite', ),
- 0x828D: ('CFARepeatPatternDim', ),
- 0x828E: ('CFAPattern', ),
- 0x828F: ('BatteryLevel', ),
- 0x8298: ('Copyright', ),
- 0x829A: ('ExposureTime', ),
- 0x829D: ('FNumber', ),
- 0x83BB: ('IPTC/NAA', ),
- 0x8769: ('ExifOffset', ),
- 0x8773: ('InterColorProfile', ),
- 0x8822: ('ExposureProgram',
- {0: 'Unidentified',
- 1: 'Manual',
- 2: 'Program Normal',
- 3: 'Aperture Priority',
- 4: 'Shutter Priority',
- 5: 'Program Creative',
- 6: 'Program Action',
- 7: 'Portrait Mode',
- 8: 'Landscape Mode'}),
- 0x8824: ('SpectralSensitivity', ),
- 0x8825: ('GPSInfo', ),
- 0x8827: ('ISOSpeedRatings', ),
- 0x8828: ('OECF', ),
- # print as string
- 0x9000: ('ExifVersion', lambda x: ''.join(map(chr, x))),
- 0x9003: ('DateTimeOriginal', ),
- 0x9004: ('DateTimeDigitized', ),
- 0x9101: ('ComponentsConfiguration',
- {0: '',
- 1: 'Y',
- 2: 'Cb',
- 3: 'Cr',
- 4: 'Red',
- 5: 'Green',
- 6: 'Blue'}),
- 0x9102: ('CompressedBitsPerPixel', ),
- 0x9201: ('ShutterSpeedValue', ),
- 0x9202: ('ApertureValue', ),
- 0x9203: ('BrightnessValue', ),
- 0x9204: ('ExposureBiasValue', ),
- 0x9205: ('MaxApertureValue', ),
- 0x9206: ('SubjectDistance', ),
- 0x9207: ('MeteringMode',
- {0: 'Unidentified',
- 1: 'Average',
- 2: 'CenterWeightedAverage',
- 3: 'Spot',
- 4: 'MultiSpot'}),
- 0x9208: ('LightSource',
- {0: 'Unknown',
- 1: 'Daylight',
- 2: 'Fluorescent',
- 3: 'Tungsten',
- 10: 'Flash',
- 17: 'Standard Light A',
- 18: 'Standard Light B',
- 19: 'Standard Light C',
- 20: 'D55',
- 21: 'D65',
- 22: 'D75',
- 255: 'Other'}),
- 0x9209: ('Flash', {0: 'No',
- 1: 'Fired',
- 5: 'Fired (?)', # no return sensed
- 7: 'Fired (!)', # return sensed
- 9: 'Fill Fired',
- 13: 'Fill Fired (?)',
- 15: 'Fill Fired (!)',
- 16: 'Off',
- 24: 'Auto Off',
- 25: 'Auto Fired',
- 29: 'Auto Fired (?)',
- 31: 'Auto Fired (!)',
- 32: 'Not Available'}),
- 0x920A: ('FocalLength', ),
- 0x927C: ('MakerNote', ),
- # print as string
- 0x9286: ('UserComment', lambda x: ''.join(map(chr, x))),
- 0x9290: ('SubSecTime', ),
- 0x9291: ('SubSecTimeOriginal', ),
- 0x9292: ('SubSecTimeDigitized', ),
- # print as string
- 0xA000: ('FlashPixVersion', lambda x: ''.join(map(chr, x))),
- 0xA001: ('ColorSpace', ),
- 0xA002: ('ExifImageWidth', ),
- 0xA003: ('ExifImageLength', ),
- 0xA005: ('InteroperabilityOffset', ),
- 0xA20B: ('FlashEnergy', ), # 0x920B in TIFF/EP
- 0xA20C: ('SpatialFrequencyResponse', ), # 0x920C - -
- 0xA20E: ('FocalPlaneXResolution', ), # 0x920E - -
- 0xA20F: ('FocalPlaneYResolution', ), # 0x920F - -
- 0xA210: ('FocalPlaneResolutionUnit', ), # 0x9210 - -
- 0xA214: ('SubjectLocation', ), # 0x9214 - -
- 0xA215: ('ExposureIndex', ), # 0x9215 - -
- 0xA217: ('SensingMethod', ), # 0x9217 - -
- 0xA300: ('FileSource',
- {3: 'Digital Camera'}),
- 0xA301: ('SceneType',
- {1: 'Directly Photographed'}),
- }
-
- # interoperability tags
- INTR_TAGS={
- 0x0001: ('InteroperabilityIndex', ),
- 0x0002: ('InteroperabilityVersion', ),
- 0x1000: ('RelatedImageFileFormat', ),
- 0x1001: ('RelatedImageWidth', ),
- 0x1002: ('RelatedImageLength', ),
- }
-
- # GPS tags (not used yet, haven't seen camera with GPS)
- GPS_TAGS={
- 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', )
- }
-
- # Nikon E99x MakerNote Tags
- # http://members.tripod.com/~tawba/990exif.htm
- MAKERNOTE_NIKON_NEWER_TAGS={
- 0x0002: ('ISOSetting', ),
- 0x0003: ('ColorMode', ),
- 0x0004: ('Quality', ),
- 0x0005: ('Whitebalance', ),
- 0x0006: ('ImageSharpening', ),
- 0x0007: ('FocusMode', ),
- 0x0008: ('FlashSetting', ),
- 0x000F: ('ISOSelection', ),
- 0x0080: ('ImageAdjustment', ),
- 0x0082: ('AuxiliaryLens', ),
- 0x0085: ('ManualFocusDistance', ),
- 0x0086: ('DigitalZoomFactor', ),
- 0x0088: ('AFFocusPosition',
- {0x0000: 'Center',
- 0x0100: 'Top',
- 0x0200: 'Bottom',
- 0x0300: 'Left',
- 0x0400: 'Right'}),
- 0x0094: ('Saturation',
- {-3: 'B&W',
- -2: '-2',
- -1: '-1',
- 0: '0',
- 1: '1',
- 2: '2'}),
- 0x0095: ('NoiseReduction', ),
- 0x0010: ('DataDump', )
- }
-
- MAKERNOTE_NIKON_OLDER_TAGS={
- 0x0003: ('Quality',
- {1: 'VGA Basic',
- 2: 'VGA Normal',
- 3: 'VGA Fine',
- 4: 'SXGA Basic',
- 5: 'SXGA Normal',
- 6: 'SXGA Fine'}),
- 0x0004: ('ColorMode',
- {1: 'Color',
- 2: 'Monochrome'}),
- 0x0005: ('ImageAdjustment',
- {0: 'Normal',
- 1: 'Bright+',
- 2: 'Bright-',
- 3: 'Contrast+',
- 4: 'Contrast-'}),
- 0x0006: ('CCDSpeed',
- {0: 'ISO 80',
- 2: 'ISO 160',
- 4: 'ISO 320',
- 5: 'ISO 100'}),
- 0x0007: ('WhiteBalance',
- {0: 'Auto',
- 1: 'Preset',
- 2: 'Daylight',
- 3: 'Incandescent',
- 4: 'Fluorescent',
- 5: 'Cloudy',
- 6: 'Speed Light'})
- }
-
- # decode Olympus SpecialMode tag in MakerNote
- def olympus_special_mode(v):
- a={
- 0: 'Normal',
- 1: 'Unknown',
- 2: 'Fast',
- 3: 'Panorama'}
- b={
- 0: 'Non-panoramic',
- 1: 'Left to right',
- 2: 'Right to left',
- 3: 'Bottom to top',
- 4: 'Top to bottom'}
- return '%s - sequence %d - %s' % (a[v[0]], v[1], b[v[2]])
-
- MAKERNOTE_OLYMPUS_TAGS={
- # ah HAH! those sneeeeeaky bastids! this is how they get past the fact
- # that a JPEG thumbnail is not allowed in an uncompressed TIFF file
- 0x0100: ('JPEGThumbnail', ),
- 0x0200: ('SpecialMode', olympus_special_mode),
- 0x0201: ('JPEGQual',
- {1: 'SQ',
- 2: 'HQ',
- 3: 'SHQ'}),
- 0x0202: ('Macro',
- {0: 'Normal',
- 1: 'Macro'}),
- 0x0204: ('DigitalZoom', ),
- 0x0207: ('SoftwareRelease', ),
- 0x0208: ('PictureInfo', ),
- # print as string
- 0x0209: ('CameraID', lambda x: ''.join(map(chr, x))),
- 0x0F00: ('DataDump', )
- }
-
- MAKERNOTE_CASIO_TAGS={
- 0x0001: ('RecordingMode',
- {1: 'Single Shutter',
- 2: 'Panorama',
- 3: 'Night Scene',
- 4: 'Portrait',
- 5: 'Landscape'}),
- 0x0002: ('Quality',
- {1: 'Economy',
- 2: 'Normal',
- 3: 'Fine'}),
- 0x0003: ('FocusingMode',
- {2: 'Macro',
- 3: 'Auto Focus',
- 4: 'Manual Focus',
- 5: 'Infinity'}),
- 0x0004: ('FlashMode',
- {1: 'Auto',
- 2: 'On',
- 3: 'Off',
- 4: 'Red Eye Reduction'}),
- 0x0005: ('FlashIntensity',
- {11: 'Weak',
- 13: 'Normal',
- 15: 'Strong'}),
- 0x0006: ('Object Distance', ),
- 0x0007: ('WhiteBalance',
- {1: 'Auto',
- 2: 'Tungsten',
- 3: 'Daylight',
- 4: 'Fluorescent',
- 5: 'Shade',
- 129: 'Manual'}),
- 0x000B: ('Sharpness',
- {0: 'Normal',
- 1: 'Soft',
- 2: 'Hard'}),
- 0x000C: ('Contrast',
- {0: 'Normal',
- 1: 'Low',
- 2: 'High'}),
- 0x000D: ('Saturation',
- {0: 'Normal',
- 1: 'Low',
- 2: 'High'}),
- 0x0014: ('CCDSpeed',
- {64: 'Normal',
- 80: 'Normal',
- 100: 'High',
- 125: '+1.0',
- 244: '+3.0',
- 250: '+2.0',})
- }
-
- MAKERNOTE_FUJIFILM_TAGS={
- 0x0000: ('NoteVersion', lambda x: ''.join(map(chr, x))),
- 0x1000: ('Quality', ),
- 0x1001: ('Sharpness',
- {1: 'Soft',
- 2: 'Soft',
- 3: 'Normal',
- 4: 'Hard',
- 5: 'Hard'}),
- 0x1002: ('WhiteBalance',
- {0: 'Auto',
- 256: 'Daylight',
- 512: 'Cloudy',
- 768: 'DaylightColor-Fluorescent',
- 769: 'DaywhiteColor-Fluorescent',
- 770: 'White-Fluorescent',
- 1024: 'Incandescent',
- 3840: 'Custom'}),
- 0x1003: ('Color',
- {0: 'Normal',
- 256: 'High',
- 512: 'Low'}),
- 0x1004: ('Tone',
- {0: 'Normal',
- 256: 'High',
- 512: 'Low'}),
- 0x1010: ('FlashMode',
- {0: 'Auto',
- 1: 'On',
- 2: 'Off',
- 3: 'Red Eye Reduction'}),
- 0x1011: ('FlashStrength', ),
- 0x1020: ('Macro',
- {0: 'Off',
- 1: 'On'}),
- 0x1021: ('FocusMode',
- {0: 'Auto',
- 1: 'Manual'}),
- 0x1030: ('SlowSync',
- {0: 'Off',
- 1: 'On'}),
- 0x1031: ('PictureMode',
- {0: 'Auto',
- 1: 'Portrait',
- 2: 'Landscape',
- 4: 'Sports',
- 5: 'Night',
- 6: 'Program AE',
- 256: 'Aperture Priority AE',
- 512: 'Shutter Priority AE',
- 768: 'Manual Exposure'}),
- 0x1100: ('MotorOrBracket',
- {0: 'Off',
- 1: 'On'}),
- 0x1300: ('BlurWarning',
- {0: 'Off',
- 1: 'On'}),
- 0x1301: ('FocusWarning',
- {0: 'Off',
- 1: 'On'}),
- 0x1302: ('AEWarning',
- {0: 'Off',
- 1: 'On'})
- }
-
- MAKERNOTE_CANON_TAGS={
- 0x0006: ('ImageType', ),
- 0x0007: ('FirmwareVersion', ),
- 0x0008: ('ImageNumber', ),
- 0x0009: ('OwnerName', )
- }
-
- # see http://www.burren.cx/david/canon.html by David Burren
- # this is in element offset, name, optional value dictionary format
- MAKERNOTE_CANON_TAG_0x001={
- 1: ('Macromode',
- {1: 'Macro',
- 2: 'Normal'}),
- 2: ('SelfTimer', ),
- 3: ('Quality',
- {2: 'Normal',
- 3: 'Fine',
- 5: 'Superfine'}),
- 4: ('FlashMode',
- {0: 'Flash Not Fired',
- 1: 'Auto',
- 2: 'On',
- 3: 'Red-Eye Reduction',
- 4: 'Slow Synchro',
- 5: 'Auto + Red-Eye Reduction',
- 6: 'On + Red-Eye Reduction',
- 16: 'external flash'}),
- 5: ('ContinuousDriveMode',
- {0: 'Single Or Timer',
- 1: 'Continuous'}),
- 7: ('FocusMode',
- {0: 'One-Shot',
- 1: 'AI Servo',
- 2: 'AI Focus',
- 3: 'MF',
- 4: 'Single',
- 5: 'Continuous',
- 6: 'MF'}),
- 10: ('ImageSize',
- {0: 'Large',
- 1: 'Medium',
- 2: 'Small'}),
- 11: ('EasyShootingMode',
- {0: 'Full Auto',
- 1: 'Manual',
- 2: 'Landscape',
- 3: 'Fast Shutter',
- 4: 'Slow Shutter',
- 5: 'Night',
- 6: 'B&W',
- 7: 'Sepia',
- 8: 'Portrait',
- 9: 'Sports',
- 10: 'Macro/Close-Up',
- 11: 'Pan Focus'}),
- 12: ('DigitalZoom',
- {0: 'None',
- 1: '2x',
- 2: '4x'}),
- 13: ('Contrast',
- {0xFFFF: 'Low',
- 0: 'Normal',
- 1: 'High'}),
- 14: ('Saturation',
- {0xFFFF: 'Low',
- 0: 'Normal',
- 1: 'High'}),
- 15: ('Sharpness',
- {0xFFFF: 'Low',
- 0: 'Normal',
- 1: 'High'}),
- 16: ('ISO',
- {0: 'See ISOSpeedRatings Tag',
- 15: 'Auto',
- 16: '50',
- 17: '100',
- 18: '200',
- 19: '400'}),
- 17: ('MeteringMode',
- {3: 'Evaluative',
- 4: 'Partial',
- 5: 'Center-weighted'}),
- 18: ('FocusType',
- {0: 'Manual',
- 1: 'Auto',
- 3: 'Close-Up (Macro)',
- 8: 'Locked (Pan Mode)'}),
- 19: ('AFPointSelected',
- {0x3000: 'None (MF)',
- 0x3001: 'Auto-Selected',
- 0x3002: 'Right',
- 0x3003: 'Center',
- 0x3004: 'Left'}),
- 20: ('ExposureMode',
- {0: 'Easy Shooting',
- 1: 'Program',
- 2: 'Tv-priority',
- 3: 'Av-priority',
- 4: 'Manual',
- 5: 'A-DEP'}),
- 23: ('LongFocalLengthOfLensInFocalUnits', ),
- 24: ('ShortFocalLengthOfLensInFocalUnits', ),
- 25: ('FocalUnitsPerMM', ),
- 28: ('FlashActivity',
- {0: 'Did Not Fire',
- 1: 'Fired'}),
- 29: ('FlashDetails',
- {14: 'External E-TTL',
- 13: 'Internal Flash',
- 11: 'FP Sync Used',
- 7: '2nd("Rear")-Curtain Sync Used',
- 4: 'FP Sync Enabled'}),
- 32: ('FocusMode',
- {0: 'Single',
- 1: 'Continuous'})
- }
-
- MAKERNOTE_CANON_TAG_0x004={
- 7: ('WhiteBalance',
- {0: 'Auto',
- 1: 'Sunny',
- 2: 'Cloudy',
- 3: 'Tungsten',
- 4: 'Fluorescent',
- 5: 'Flash',
- 6: 'Custom'}),
- 9: ('SequenceNumber', ),
- 14: ('AFPointUsed', ),
- 15: ('FlashBias',
- {0XFFC0: '-2 EV',
- 0XFFCC: '-1.67 EV',
- 0XFFD0: '-1.50 EV',
- 0XFFD4: '-1.33 EV',
- 0XFFE0: '-1 EV',
- 0XFFEC: '-0.67 EV',
- 0XFFF0: '-0.50 EV',
- 0XFFF4: '-0.33 EV',
- 0X0000: '0 EV',
- 0X000C: '0.33 EV',
- 0X0010: '0.50 EV',
- 0X0014: '0.67 EV',
- 0X0020: '1 EV',
- 0X002C: '1.33 EV',
- 0X0030: '1.50 EV',
- 0X0034: '1.67 EV',
- 0X0040: '2 EV'}),
- 19: ('SubjectDistance', )
- }
-
- # extract multibyte integer in Motorola format (little endian)
- def s2n_motorola(str):
- x=0
- for c in str:
- x=(x << 8) | ord(c)
- return x
-
- # extract multibyte integer in Intel format (big endian)
- def s2n_intel(str):
- x=0
- y=0L
- for c in str:
- x=x | (ord(c) << y)
- y=y+8
- return x
-
- # ratio object that eventually will be able to reduce itself to lowest
- # common denominator for printing
- def gcd(a, b):
- if b == 0:
- return a
- else:
- return gcd(b, a % b)
-
- class Ratio:
- def __init__(self, num, den):
- self.num=num
- self.den=den
-
- def __repr__(self):
- self.reduce()
- if self.den == 1:
- return str(self.num)
- return '%d/%d' % (self.num, self.den)
-
- def reduce(self):
- div=gcd(self.num, self.den)
- if div > 1:
- self.num=self.num/div
- self.den=self.den/div
-
- # for ease of dealing with tags
- class IFD_Tag:
- def __init__(self, printable, tag, field_type, values, field_offset,
- field_length):
- # printable version of data
- self.printable=printable
- # tag ID number
- self.tag=tag
- # field type as index into FIELD_TYPES
- self.field_type=field_type
- # offset of start of field in bytes from beginning of IFD
- self.field_offset=field_offset
- # length of data field in bytes
- self.field_length=field_length
- # either a string or array of data items
- self.values=values
-
- def __str__(self):
- return self.printable
-
- def __repr__(self):
- return '(0x%04X) %s=%s @ %d' % (self.tag,
- FIELD_TYPES[self.field_type][2],
- self.printable,
- self.field_offset)
-
- # class that handles an EXIF header
- class EXIF_header:
- def __init__(self, file, endian, offset, debug=0):
- self.file=file
- self.endian=endian
- self.offset=offset
- self.debug=debug
- self.tags={}
-
- # convert slice to integer, based on sign and endian flags
- def s2n(self, offset, length, signed=0):
- self.file.seek(self.offset+offset)
- slice=self.file.read(length)
- if self.endian == 'I':
- val=s2n_intel(slice)
- else:
- val=s2n_motorola(slice)
- # Sign extension ?
- if signed:
- #msb=1 << (8*length-1)
- #if val & msb:
- # val=val-(msb << 1)
- pass
- return val
-
- # convert offset to string
- def n2s(self, offset, length):
- s=''
- for i in range(length):
- if self.endian == 'I':
- s=s+chr(offset & 0xFF)
- else:
- s=chr(offset & 0xFF)+s
- offset=offset >> 8
- return s
-
- # return first IFD
- def first_IFD(self):
- return self.s2n(4, 4)
-
- # return pointer to next IFD
- def next_IFD(self, ifd):
- entries=self.s2n(ifd, 2)
- return self.s2n(ifd+2+12*entries, 4)
-
- # return list of IFDs in header
- def list_IFDs(self):
- i=self.first_IFD()
- a=[]
- while i:
- a.append(i)
- i=self.next_IFD(i)
- return a
-
- # return list of entries in this IFD
- def dump_IFD(self, ifd, ifd_name, dict=EXIF_TAGS):
- entries=self.s2n(ifd, 2)
- for i in range(entries):
- entry=ifd+2+12*i
- tag=self.s2n(entry, 2)
- field_type=self.s2n(entry+2, 2)
- if not 0 < field_type < len(FIELD_TYPES):
- # unknown field type
- raise ValueError, \
- 'unknown type %d in tag 0x%04X' % (field_type, tag)
- typelen=FIELD_TYPES[field_type][0]
- count=self.s2n(entry+4, 4)
- offset=entry+8
- if count*typelen > 4:
- # not the value, it's a pointer to the value
- offset=self.s2n(offset, 4)
- field_offset=offset
- if field_type == 2:
- # special case: null-terminated ASCII string
- if count != 0:
- self.file.seek(self.offset+offset)
- values=self.file.read(count).strip().replace('\x00','')
- else:
- values=''
- else:
- values=[]
- signed=(field_type in [6, 8, 9, 10])
- for j in range(count):
- if field_type in (5, 10):
- # a ratio
- value_j=Ratio(self.s2n(offset, 4, signed),
- self.s2n(offset+4, 4, signed))
- else:
- value_j=self.s2n(offset, typelen, signed)
- values.append(value_j)
- offset=offset+typelen
- # now "values" is either a string or an array
- if count == 1 and field_type != 2:
- printable=str(values[0])
- else:
- printable=str(values)
- # figure out tag name
- tag_entry=dict.get(tag)
- if tag_entry:
- tag_name=tag_entry[0]
- if len(tag_entry) != 1:
- # optional 2nd tag element is present
- if callable(tag_entry[1]):
- # call mapping function
- printable=tag_entry[1](values)
- else:
- printable=''
- for i in values:
- # use LUT for this tag
- printable+=tag_entry[1].get(i, repr(i))
- else:
- tag_name='Tag 0x%04X' % tag
- self.tags[ifd_name+' '+tag_name]=IFD_Tag(printable, tag,
- field_type,
- values, field_offset,
- count*typelen)
- if self.debug:
- print ' %s: %s' % (tag_name,
- repr(self.tags[ifd_name+' '+tag_name]))
-
- # extract uncompressed TIFF thumbnail (like pulling teeth)
- # we take advantage of the pre-existing layout in the thumbnail IFD as
- # much as possible
- def extract_TIFF_thumbnail(self, thumb_ifd):
- entries=self.s2n(thumb_ifd, 2)
- # this is header plus offset to IFD ...
- if self.endian == 'M':
- tiff='MM\x00*\x00\x00\x00\x08'
- else:
- tiff='II*\x00\x08\x00\x00\x00'
- # ... plus thumbnail IFD data plus a null "next IFD" pointer
- self.file.seek(self.offset+thumb_ifd)
- tiff+=self.file.read(entries*12+2)+'\x00\x00\x00\x00'
-
- # fix up large value offset pointers into data area
- for i in range(entries):
- entry=thumb_ifd+2+12*i
- tag=self.s2n(entry, 2)
- field_type=self.s2n(entry+2, 2)
- typelen=FIELD_TYPES[field_type][0]
- count=self.s2n(entry+4, 4)
- oldoff=self.s2n(entry+8, 4)
- # start of the 4-byte pointer area in entry
- ptr=i*12+18
- # remember strip offsets location
- if tag == 0x0111:
- strip_off=ptr
- strip_len=count*typelen
- # is it in the data area?
- if count*typelen > 4:
- # update offset pointer (nasty "strings are immutable" crap)
- # should be able to say "tiff[ptr:ptr+4]=newoff"
- newoff=len(tiff)
- tiff=tiff[:ptr]+self.n2s(newoff, 4)+tiff[ptr+4:]
- # remember strip offsets location
- if tag == 0x0111:
- strip_off=newoff
- strip_len=4
- # get original data and store it
- self.file.seek(self.offset+oldoff)
- tiff+=self.file.read(count*typelen)
-
- # add pixel strips and update strip offset info
- old_offsets=self.tags['Thumbnail StripOffsets'].values
- old_counts=self.tags['Thumbnail StripByteCounts'].values
- for i in range(len(old_offsets)):
- # update offset pointer (more nasty "strings are immutable" crap)
- offset=self.n2s(len(tiff), strip_len)
- tiff=tiff[:strip_off]+offset+tiff[strip_off+strip_len:]
- strip_off+=strip_len
- # add pixel strip to end
- self.file.seek(self.offset+old_offsets[i])
- tiff+=self.file.read(old_counts[i])
-
- self.tags['TIFFThumbnail']=tiff
-
- # decode all the camera-specific MakerNote formats
- def decode_maker_note(self):
- note=self.tags['EXIF MakerNote']
- make=self.tags['Image Make'].printable
- model=self.tags['Image Model'].printable
-
- # Nikon
- if make == 'NIKON':
- if note.values[0:5] == [78, 105, 107, 111, 110]: # "Nikon"
- # older model
- self.dump_IFD(note.field_offset+8, 'MakerNote',
- dict=MAKERNOTE_NIKON_OLDER_TAGS)
- else:
- # newer model (E99x or D1)
- self.dump_IFD(note.field_offset, 'MakerNote',
- dict=MAKERNOTE_NIKON_NEWER_TAGS)
- return
-
- # Olympus
- if make[:7] == 'OLYMPUS':
- self.dump_IFD(note.field_offset+8, 'MakerNote',
- dict=MAKERNOTE_OLYMPUS_TAGS)
- return
-
- # Casio
- if make == 'Casio':
- self.dump_IFD(note.field_offset, 'MakerNote',
- dict=MAKERNOTE_CASIO_TAGS)
- return
-
- # Fujifilm
- if make == 'FUJIFILM':
- # bug: everything else is "Motorola" endian, but the MakerNote
- # is "Intel" endian
- endian=self.endian
- self.endian='I'
- # bug: IFD offsets are from beginning of MakerNote, not
- # beginning of file header
- offset=self.offset
- self.offset+=note.field_offset
- # process note with bogus values (note is actually at offset 12)
- self.dump_IFD(12, 'MakerNote', dict=MAKERNOTE_FUJIFILM_TAGS)
- # reset to correct values
- self.endian=endian
- self.offset=offset
- return
-
- # Canon
- if make == 'Canon':
- self.dump_IFD(note.field_offset, 'MakerNote',
- dict=MAKERNOTE_CANON_TAGS)
- for i in (('MakerNote Tag 0x0001', MAKERNOTE_CANON_TAG_0x001),
- ('MakerNote Tag 0x0004', MAKERNOTE_CANON_TAG_0x004)):
- self.canon_decode_tag(self.tags[i[0]].values, i[1])
- return
-
- # decode Canon MakerNote tag based on offset within tag
- # see http://www.burren.cx/david/canon.html by David Burren
- def canon_decode_tag(self, value, dict):
- for i in range(1, len(value)):
- x=dict.get(i, ('Unknown', ))
- if self.debug:
- print i, x
- name=x[0]
- if len(x) > 1:
- val=x[1].get(value[i], 'Unknown')
- else:
- val=value[i]
- # it's not a real IFD Tag but we fake one to make everybody
- # happy. this will have a "proprietary" type
- self.tags['MakerNote '+name]=IFD_Tag(str(val), None, 0, None,
- None, None)
-
- # process an image file (expects an open file object)
- # this is the function that has to deal with all the arbitrary nasty bits
- # of the EXIF standard
- def process_file(file, debug=0):
- # determine whether it's a JPEG or TIFF
- data=file.read(12)
- if data[0:4] in ['II*\x00', 'MM\x00*']:
- # it's a TIFF file
- file.seek(0)
- endian=file.read(1)
- file.read(1)
- offset=0
- elif data[0:2] == '\xFF\xD8':
- # it's a JPEG file
- # skip JFIF style header(s)
- while data[2] == '\xFF' and data[6:10] in ('JFIF', 'JFXX', 'OLYM'):
- length=ord(data[4])*256+ord(data[5])
- file.read(length-8)
- # fake an EXIF beginning of file
- data='\xFF\x00'+file.read(10)
- if data[2] == '\xFF' and data[6:10] == 'Exif':
- # detected EXIF header
- offset=file.tell()
- endian=file.read(1)
- else:
- # no EXIF information
- return {}
- else:
- # file format not recognized
- return {}
-
- # deal with the EXIF info we found
- if debug:
- print {'I': 'Intel', 'M': 'Motorola'}[endian], 'format'
- hdr=EXIF_header(file, endian, offset, debug)
- ifd_list=hdr.list_IFDs()
- ctr=0
- for i in ifd_list:
- if ctr == 0:
- IFD_name='Image'
- elif ctr == 1:
- IFD_name='Thumbnail'
- thumb_ifd=i
- else:
- IFD_name='IFD %d' % ctr
- if debug:
- print ' IFD %d (%s) at offset %d:' % (ctr, IFD_name, i)
- hdr.dump_IFD(i, IFD_name)
- # EXIF IFD
- exif_off=hdr.tags.get(IFD_name+' ExifOffset')
- if exif_off:
- if debug:
- print ' EXIF SubIFD at offset %d:' % exif_off.values[0]
- hdr.dump_IFD(exif_off.values[0], 'EXIF')
- # Interoperability IFD contained in EXIF IFD
- intr_off=hdr.tags.get('EXIF SubIFD InteroperabilityOffset')
- if intr_off:
- if debug:
- print ' EXIF Interoperability SubSubIFD at offset %d:' \
- % intr_off.values[0]
- hdr.dump_IFD(intr_off.values[0], 'EXIF Interoperability',
- dict=INTR_TAGS)
- # GPS IFD
- gps_off=hdr.tags.get(IFD_name+' GPSInfo')
- if gps_off:
- if debug:
- print ' GPS SubIFD at offset %d:' % gps_off.values[0]
- hdr.dump_IFD(gps_off.values[0], 'GPS', dict=GPS_TAGS)
- ctr+=1
-
- # extract uncompressed TIFF thumbnail
- thumb=hdr.tags.get('Thumbnail Compression')
- if thumb and thumb.printable == 'Uncompressed TIFF':
- hdr.extract_TIFF_thumbnail(thumb_ifd)
-
- # JPEG thumbnail (thankfully the JPEG data is stored as a unit)
- thumb_off=hdr.tags.get('Thumbnail JPEGInterchangeFormat')
- if thumb_off:
- file.seek(offset+thumb_off.values[0])
- size=hdr.tags['Thumbnail JPEGInterchangeFormatLength'].values[0]
- hdr.tags['JPEGThumbnail']=file.read(size)
-
- # deal with MakerNote contained in EXIF IFD
- if hdr.tags.has_key('EXIF MakerNote'):
- hdr.decode_maker_note()
-
- # Sometimes in a TIFF file, a JPEG thumbnail is hidden in the MakerNote
- # since it's not allowed in a uncompressed TIFF IFD
- if not hdr.tags.has_key('JPEGThumbnail'):
- thumb_off=hdr.tags.get('MakerNote JPEGThumbnail')
- if thumb_off:
- file.seek(offset+thumb_off.values[0])
- hdr.tags['JPEGThumbnail']=file.read(thumb_off.field_length)
-
- return hdr.tags
-
- # library test/debug function (dump given files)
- if __name__ == '__main__':
- import sys
-
- if len(sys.argv) < 2:
- print 'Usage: %s files...\n' % sys.argv[0]
- sys.exit(0)
-
- for filename in sys.argv[1:]:
- try:
- file=open(filename, 'rb')
- except:
- print filename, 'unreadable'
- print
- continue
- print filename+':'
- # data=process_file(file, 1) # with debug info
- data=process_file(file)
- if not data:
- print 'No EXIF information found'
- continue
-
- x=data.keys()
- x.sort()
- for i in x:
- if i in ('JPEGThumbnail', 'TIFFThumbnail'):
- continue
- try:
- print ' %s (%s): %s' % \
- (i, FIELD_TYPES[data[i].field_type][2], data[i].printable)
- except:
- print 'error', i, '"', data[i], '"'
- if data.has_key('JPEGThumbnail'):
- print 'File has JPEG thumbnail'
- print
-