What is Metadata?
Information can be extremely complicated. Searching through data can be like looking for that needle in a haystack. Metadata is one way to help accomplish gaining control over data. It is data about data. Similar to the days before computing when you went to the library and had to look through the card catalog for information on locating a book. The card catalog held a searchable index of information that would help the user find more relevant data on the bookshelves.
Though various forms of “metadata” has existed for centuries, the term itself was coined by two MIT researchers, Stuart McIntosh and David Griffel. In 1967, they produced a report regarding the indexing of data. They described a need to search computer data with set definitions. The called this extra data to help with searches as a “meta language.” They discussed the process of storing data records and the given purpose that data is collected. “If many different types of records are-generated, it becomes necessary to keep a record (metadata - bibliographic data) of the data records.”
Metadata is generally a way to describe what other data you are looking for. It is a filing system of sorts. This information can also give out details that the user may not want to share. An example would be in digital images; metadata is held behind the image. It can give information such as the person who took the photo, date, time, and even the GPS location when taken. Learning how EXIF data tracks your files, can help you better manage them, or change the settings to protect your privacy.
EXIF data is a form of metadata. EXIF is short for Exchangeable Image File Format. These are standard data requirements or options for image files. Photos contain EXIF data, and you have some control over how much data is added to your images if you check your camera’s settings. The EXIF data contains information about your camera or phone, and possibly where the photo was taken. Any time you take a picture with your digital camera or cell phone, this data is added in the background of your photograph. If you are sharing this photo online, then anyone can look at your EXIF data and get personal and private information from them. If you are posting pictures taken at your home, any internet stranger can find you.
In addition to your camera type, possibly your name, your GPS location, there is a great deal more information that EXIF data can contain. Your JPEG file can contain copyright information, date, time, camera settings, and even information on changes made to the photo, including when the photo was altered and by whom.
Why does a photo contain GPS location at all? Because all metadata is meant to be a way to search for other data. On many photo sharing sites, a geological location can be entered, and all photographs taken in a specific area can be found. There are legitimate reasons to have this as a search point for metadata. This data can allow other users to know the exact location the photo was taken, find it on a map, and even use it to participate in social media functions or events.
If you are a private individual and don’t wish to share your geological location with the rest of the world, there are steps that you can take to remove all EXIF data from your images. For those that are interested, the following includes some basic instructions on how to delete this data.
Removing EXIF Data from Images
Any time you take a new photograph, EXIF data is added. There is no way to prevent this, but many phones will allow the removal of GPS data on all photos. You just have to go into your camera’s settings and turn off the GPS locator. Adding GPS location to images or any other type of file is called geotagging. If you select your settings to not include geolocations in your photos, that information will not be included in the metadata recorded. However, once you have already taken a photograph, you can go back into the file and remove ALL EXIF data from the background metadata. Other than removing GPS and personal info, why should you take the time to remove the EXIF data from your work?
There are many reasons to remove EXIF fully or partially from files:
- First, as discussed, to remove any sensitive information that you may not want to publish, such as your personal information, name, and or geolocation.
- When posting images to web sites, all extra information, including metadata, means larger files. If you want to keep everything moving at a rapid pace and quick downloads – it is better to keep the file sizes of images as small as possible.
- Do you take photos as an art form or business? Remove metadata to protect your work. Don’t give away your copyright on the image by handing out all the details to recreate it. Additional information can include your camera gear, settings, and any alteration adjustments.
- It is important to remove the JUNK from JPEG files to keep them smaller and choose what EXIF data remains, keeping all metadata about you and your work in your own hands.
Many applications can be used to open your photograph files or images and view, change, or remove EXIF data from your files. One of these programs is called Lightroom. You can also use photoshop and a variety of other applications.
Looking at your Metadata
There are many ways to view the EXIF data on an image file. Lightroom and photoshop are excellent resources for viewing metadata. If you don’t have these, how can you take a look at the EXIF data you are sending out with your images? Let’s break down different ways you can view the metadata in your pictures.
As an add-on, FIREFOX supplies an EXIF-viewer. After installing the application and restarting FIREFOX, then you should be able from that point on to view the EXIF data on any image by simply right-clicking and choosing EXIF-viewer.
Chrome also has an extension EXIF-viewer. Once you “add to Chrome,” you can also right-click any image and choose the ‘Show EXIF data’ option. This will bring up a pop up that will give you all the metadata information available for the image.
Not everyone is thrilled with many extensions added to their internet browser. That is OK. In fact, you can use the Windows OS also to view the EXIF data in your images. If your pictures are already on your computer, it is relatively easy to do. Otherwise, you will have to upload any photos you want to view onto your computer. Information found using the Windows OS is limited, and if you want more details, then you will have to install a viewer of some sort. If your photo or image file is on your computer, simply right click and choose ‘details.’
- CaseGuard Studio
CaseGuard Studio automatically pulls, organizes, and displays all EXIF data associated with any file added to it. Multiple reports can also be printed from CaseGuard Studio to include the EXIF data associated with the file.
Choosing a viewer and installing it will save time and get the most detailed information on the images. A popular metadata viewer is called ACDSee. ACDSee has a variety of packages and software options.
Lightroom is a post-processing tool created for Adobe. Lightroom is a preferred service for many professional photographers. It includes everything you need to edit, organize, or store photos through the Cloud. This allows you to have access to your images from any device. Using the Lightroom application, you will be able to create, organize, and edit photos just the way you want.
If installing an extension or purchasing a software application is not on your list, there are other options. There are free metadata/EXIF viewers available online. You will have to upload the image file you would want to view and then take a look at the data held. One of the best free options available online is “Jeffrey’s Image Metadata Viewer.” This is an excellent free option without downloading or installing anything. There is a long list of file types that it will accept, most all of them. If you enjoy the viewer, it would be great to buy Jeffrey a cup of coffee.
Removing the Data
Now that you have discovered all the different ways that you can view the metadata left imprinted upon your image files, what if you want to change them, or erase all the information? Generally, there are three sections of EXIF data installed on your images. There is the basic EXIF data, which includes the geolocation, the camera type, and settings, along with the date and time image was created. There is also XMP data on your image file. XMP stands for Extreme Memory Profiles. The XMP data on your image will contain all the information regarding any post-processing steps taken before exporting your image file. It will include such things as a thumbnail of the image and any filters, changes, or alterations made to the original image, along with who made the changes, how and at what time and date
Now that you have a better understanding of the types of data stored in your images and how to access or alter them, you can take control of your own data that you distribute and better protect your privacy. Join us for the next article in this series that will explain how forensic specialists examine EXIF data and other sources as a way to verify sources or solve crimes.