"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.
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$ 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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