Exchangeable image file format (officially Exif, according to JEIDA/JEITA/CIPA specifications) is a standard that specifies formats for images, sound, and ancillary tags used by digital cameras (including smartphones), scanners and other systems handling image and sound files recorded by digital cameras.
The specification uses the following existing encoding formats with the addition of specific metadata tags: JPEG lossy coding for compressed image files, TIFF Rev. 6.0 (RGB or YCbCr) for uncompressed image files, and RIFF WAV for audio files (linear PCM or ITU-T G.711 μ-law PCM for uncompressed audio data, and IMA-ADPCM for compressed audio data). It does not support JPEG 2000 or GIF encoded images. This standard consists of the Exif image file specification and the Exif audio file specification.
Exif is supported by almost all camera manufacturers. The metadata tags defined in the Exif standard cover a broad spectrum:
- Camera settings: This includes static information such as the camera model and make, and information that varies with each image such as orientation (rotation), aperture, shutter speed, focal length, metering mode, and ISO speed information.
- Image metrics: Pixel dimensions, resolution, colour-space, and file-size
- Date and time information. Digital cameras will record the current date and time and save this in the metadata.
- Location information
- A thumbnail for previewing the picture on the camera’s LCD screen, in file managers, or in photo manipulation software.
- Descriptions
- Copyright information.
Exif data are embedded within the image file itself. While many recent image manipulation programs recognize and preserve Exif data when writing to a modified image, this is not the case for most older programs. Many image gallery programs also recognise Exif data and optionally display it alongside the images.
Software libraries, such as libexif for C and Adobe XMP Toolkit or Exiv2 for C++, Metadata Extractor for Java, PIL/Pillow for Python, LEADTOOLS or ExifTool for Perl, parse Exif data from files and read/write Exif tag values.
LINKS for Tools
EXIF Data — https://exifdata.com/
Jeffrey’s Image Metadata Viewer (link currently unavailable)
