exif

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"exif.c" is a simple implementation to access the Exif segment in a JPEG file. It easily enables you to get the value of the IFD tag field with such code:

TagNodeInfo *tag = getTagInfo(ifdArray, IFD_EXIF, TAG_DateTimeOriginal); printf("DateTimeOriginal = [%s]\n", tag->byteData);

-> DateTimeOriginal = [2013:09:01 09:49:00]

See "sample_main.c" and "exif.h" for details.

exif.c only uses standard C library functions. So, it will be usable in many environments. It has been tested in the following environments.

• Windows XP 32bit + 32bit Visual C++
• Windows 7 64bit + 64bit Visual C++
• Redhat Linux 32bit + 32bit gcc
• Mac OS X 64bit + 64bit gcc

building with gcc: gcc -o exif sample_main.c exif.c

building with Microsoft Visual C++: cl.exe /o exif sample_main.c exif.c

The following output is the result of the sample program.

$ exif test.jpg

[test.jpg] createIfdTableArray: result=4

{0TH IFD}

• Make: [Apple]
• Model: [iPod touch]
• Orientation: 1
• XResolution: 72/1
• YResolution: 72/1
• ResolutionUnit: 2
• Software: [6.1.4]
• DateTime: [2013:09:01 09:49:00]
• YCbCrPositioning: 1
• ExifIFDPointer: 206
• GPSInfoIFDPointer: 576

{EXIF IFD}

• ExposureTime: 1/30
• FNumber: 12/5
• ExposureProgram: 2
• PhotographicSensitivity: 400
• ExifVersion: 0 2 2 1
• DateTimeOriginal: [2013:09:01 09:49:00]
• DateTimeDigitized: [2013:09:01 09:49:00]
• ComponentsConfiguration: 0x01 0x02 0x03 0x00
• ShutterSpeedValue: 4035/821
• ApertureValue: 4845/1918
• BrightnessValue: 2234/1113
• MeteringMode: 5
• Flash: 32
• FocalLength: 77/20
• FlashPixVersion: 0 1 0 0
• ColorSpace: 1
• PixelXDimension: 960
• PixelYDimension: 720
• SensingMethod: 2
• ExposureMode: 0
• WhiteBalance: 0
• FocalLengthIn35mmFormat: 32
• SceneCaptureType: 0

{GPS IFD}

• GPSLatitudeRef: [S]
• GPSLatitude: 69/1 17/100 0/1
• GPSLongitudeRef: [E]
• GPSLongitude: 39/1 35/100 0/1
• GPSAltitudeRef: 0
• GPSAltitude: 6151/470
• GPSTimeStamp: 0/1 48/1 3921/100

{1ST IFD}

• Compression: 6
• XResolution: 72/1
• YResolution: 72/1
• ResolutionUnit: 2
• JPEGInterchangeFormat: 840
• JPEGInterchangeFormatLength: 8648

0th IFD : Model = [iPod touch] Exif IFD : DateTimeOriginal = [2013:09:01 09:49:00] GPS IFD : GPSLatitude = 69/1 17/100 0/1 removeExifSegmentFromJPEGFile: result=1

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