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EXIF Data

Here, the main data is the digital image. Metadata is complementary information: the date and time when the photo was taken, the camera model, GPS coordinates at the time of shooting, are examples of metadata used to describe a digital image.

Purpose

Before digital photography, and before the implementation of EXIF data, photographers used to note information related to their shots in a small notebook: the date, context, idea... in short, metadata!

It was impossible for them to view the photos they had just taken, and it was common to use the same film to take a photo from time to time. It sometimes took several days, weeks, months, before finishing a film, so it was impossible to remember the context of photo number three on a 36-shot film!

EXIF data then acts as a "small notebook" and allows preserving the photo's metadata, and therefore the moment of shooting. You will find here an example list of EXIF data associated with a photo.

Work to be done

We will use for our examples images from the exif-samples repository of user ianare. We will focus more specifically on photos located in the /jpg/gps/ folder of this repository.

Answer the following questions in a document that you will then submit.
  1. What does the acronym EXIF stand for?
  2. By clicking on the link to access the exif-samples repository, you can see that the user indicates information about the license under which these images are published. What is the name of this license? What does it mean?
  3. How many photos are available in the /jpg/gps/ folder?
  4. You will find on this page the EXIF data of the photo DSCN0029.jpg.
    • With what camera model was this photo taken?
    • What are the image dimensions?
    • On what date was this photo taken?
    • What are the GPS coordinates (GPS Position in English) of the photographer at the time of shooting?
    • Which country does this correspond to?
  5. You will find on this page the EXIF data of the photo DSCN0042.jpg.
    • Are the information related to the camera, date and GPS coordinates identical to those of the previous photo?
    • Which of these two photos was taken first?
  6. In your opinion, have the EXIF data of this photo been manipulated? Identify the five inconsistencies present.