EXIF : Hidden Image Secrets in Exchangeable Image File Format

EXIF stands for Exchangeable Image File Format, and is a standard for storing interchange information in image files, especially those using JPEG compression shot by digital cameras. It was written by the Japan Electronics and Information Technology Industries Association (JEITA).

Before you decide to save that image from the web, CD or presentation, modify it and label it as yours, remember an image has a lot of hidden data which shows original data and source of the image

Exif.org gives an example photo shot by a Nikon camera and the full info revealed by the image. I saved that image and a popular freeware image viewer like Irfan View gives me a lot of data. Thought there are several professional exif viewers, irfan view is my default image viewer and it works for me. Just some screenshots from the view

And it tells you about the Maker note also

It can include lot of image information like date and time, camera settings like the camera model and make, image data such as orientation, aperture, shutter speed, focal length, metering mode, and film speed information. Location information, descriptions and copyright information may also be attached.

This data is very useful for photographers who snap multiple images for that perfect photograph. It lets them compare and analyze the data. This data can be read by the digital camera software, supported printers, browsers and image editing softwares.

I also found a Firefox extension FxIF which provides quick limited EXIF information for any image on the web. Good for quick extraction of image data. Right Click Image>Properties. See data for same image –

EXIF metadata is embedded in the file and editing actions like rotating, cropping, and other photo editing actions can cause loss of this data. It is commonly applicable to JPEG and TIFF image formats.

So before you say you snapped that image today, beware that smart users might look up the EXIF metadata to find the image was 3 years old. Still saying you have a Nikon digital camera, while the image is labelled as Canon.
An image says much more than it reveals!

Share with friends

About the Author: P Chandra is editor of QOT, one of India's earliest tech bloggers since 2004. A tech enthusiast with expertise in coding, WordPress, web tools, SEO and DIY hacks.