Tutorial: Using FotoForensics

FotoForensics provides budding researchers and professional investigators access to cutting-edge tools for digital photo forensics.

FotoForensics is designed and organized for rapid analysis. With a little experience, an analyst should be able to evaluate a picture in minutes. Given training and additional experience, an analyst should be able to accurately evaluate a typical picture in seconds.

Keep in mind: analyzing pictures is a complex task. There is no one-button solution that will tell you if a picture is real or digitally altered. Because situations, content, forums, and questions are as numerous as options to modify pictures, there is no automated analysis result.

FotoForensics aims to simplify the evaluation process. It works like a microscope -- by highlighting artifacts and details that the human eye may not be able to identify. Between having the right tools and training, most people can quickly learn how to evaluate picture. FotoForensics provides the algorithms, online tutorials for self-paced learning, challenges to test your knowledge, and other resources to help you get started.

Tutorials and Training

Not everyone has the opportunity to attend an in-person training seminar. For this reason, FotoForensics has been designed for self-paced learning. The site includes tutorials that explain how to use the analyzers, challenges to test your knowledge, links to additional reading material, and more.

No "One Button Solutions"

Everybody wants a one-button solution.

Is this real?

Yes No

Unfortunately, the definition for real varies by industry.

Field	Industry Permits	Users Expect
Advertisers	Most ads include major digital alterations. The only limitations: don't alter the item too much, or represent alterations as real.	Alterations, recoloring, cropping, graphics.
Social Media	If it looks like [Celebrity name] Kim Kardashian Pee-wee Herman Jimmy Kimmel Kathy Griffin Clifford the big red dog , then it is [Celebrity name]. (Most social media followers are not picky about image quality or alterations.)	Doesn't know or doesn't care about resaves, edits, and other alterations. Just as long as it represents the subject.
Photojournalism	Minor touch-ups, cropping, and global color alterations.	Metadata annotations and pictures saved from Photoshop. Camera-originals are extremely uncommon.
UFOs	Don't laugh: this community takes analysis seriously. They typically rule out 99% of pictures; the remaining 1% are interesting.	Unaltered straight-from-the-camera originals. Anything else is an indication of alteration.
Insurance	Wants straight-from-the-camera originals.	Gets whatever the customer sends them. (Usually not what they want.) This may include resaves, annotations, and other alterations as the customer tries to be helpful by enhancing the picture to better identify the issue being claimed.

Even within the same field, different organizations may have different definitions for real. For example, media outlets like the Associated Press, Reuters, and Getty Images all have different definitions for acceptable alterations.

Without a consistent definition for real, nobody can create a one-button solution. FotoForensics provides tools that help identify alterations. However, it is up to you to determine whether any identified alterations are acceptable for a given picture or field.

Uploading Content to FotoForensics

Before you can evaluate a picture, it must be uploaded to the site.

Submit a picture for Forensic Analysis Supported formats: JPEG, PNG, WebP, HEIC, and AVIF Image URL: or Upload File: See the FAQ for submission guidelines. See the tutorials for analysis instructions.

FotoForensics provides two different methods for uploading content. Upload by URL. If the picture is available online, then users can supply the URL to the image. The URL is found at the top of your browser and typically begins with "HTTP://" or "HTTPS://". When you supply the URL, FotoForensics will retrieve the picture. Upload by File. If the file exists on your local computer system, then you can select the picture for uploading directly from your computer. With this option, you will be prompted to select the file to upload.

Upload Support

Because FotoForensics analyzes pictures and is a web-based system, there are a few upload limitations:

• Browsers: FotoForensics works best with HTML5 and CSS3. This includes most up-to-date web browsers. However, if your web browser is no longer supported by the software provider (such as Internet Explorer 9 or Chrome 21), then this site may not support your browser. Browsers that reencode pictures prior to uploading (such as Apple's Mobile Safari) are only supported for url uploads.
• Format: FotoForensics only evaluates pictures. The picture must be a JPEG, PNG, or WebP.
• Size: Uploads are limited to 10 megabytes per file. Larger uploads are likely to timeout or fail, and results can take too long to return to your browser.
• Dimensions: Pictures should be at least 100x100 pixels; thumbnail images are typically heavily postprocessed (cropped and resized) so modifications are rarely identifiable. Pictures must not be no larger than 10,000x10,000; extremely large pictures cannot be processed in real-time.
• Content: This is a public server. Do not upload pornography, nudity, or sexually explicit content.

Viewing an Analysis

After uploading content, you will be shown the analysis page.

Analysis: DigestELAGamesHidden PixelsICC+JPEG %MetadataService InfoStringsSource URL to this page: [Direct Link] [Annotated] View: [Uploaded Source Image] Share: What does this picture mean? See the tutorials for an explanation.

The main elements in the analysis window are: Main Image. The main image in the top-center of the page shows the picture being analyzed. Moving the mouse over the main image toggles between the source picture and the analysis image. This permits rapidly seeing how different elements in the picture align with analysis artifacts. Clicking on the main image also toggles between the source and analysis images. This permits using the mouse as a marker to see how a specific area compares with the analysis. Analyzers. To the left of the main image is a selectable list of analyzers. The tests are performed when the analyzer is selected, so results may take a few seconds to appear. Hovering the mouse over each analyzer displays a very brief summary. Options. Below the analyzer list is a set of optional buttons. These perform additional tasks, such as rotating the picture. Hovering the mouse over each option button displays the button's purpose. Result Area. Below the main image is the results area. This permits viewing the source and analysis side-by-side. Clicking on the result image will display it full-size. It is also the location where text results, such as metadata analysis, appears. Links. At the bottom of the page are various links. These include a direct link to the analysis page, a link to the uploaded source image, quick buttons for sharing the analysis on social networks, and a link to the tutorials.

Annotating Images

Communicating findings is an important part of image analysis. Often, analysts either resort to descriptions ("in the lower-right corner" or "next to the tree trunk"), or they load the picture into a drawing program to add annotations.

Transfering pictures to another application could result in unexpected alterations or potential chain-of-custody issues. Moreover, some forensic environments only permit authorized applications. If there are no approved programs for annotating images, then either the picture cannot be annotated, or the annotations must be carefully documented. (In every forensic environment that we have encountered, web browsers are approved applications.)

FotoForensics includes a basic annotation system. By having annotations integrated into FotoForensics, it removes the chain-of-custody and authorized application issues.

Using Annotations

Below the list of analyzers is an option button with an "A" on it: A. Clicking on this button opens a menu of annotation options. These options include:

Creating Annotations

• Color: Select the color for the next annotation. (The default color is red.) The color label will change to show the selected color.
• A Add Arrows: With this button selected, you can click on the image to draw an arrow. Wherever the mouse is clicked first becomes the arrowhead. Then drag out the arrow's tail. Releasing the mouse button completes the arrow. Holding down the shift key creates a horizontal, vertical, or diagonal arrow.
• B Add Lines: Over the image, click and drag the mouse to draw a line. Holding down the shift key creates a horizontal, vertical, or diagonal line.
• C Add Boxes: Over the image, click and drag the mouse to draw a box. Holding down the shift key while dragging creates a square.
• D Add Ovals: Over the image, click and drag the mouse to draw an oval. Wherever you click first will become the center of the oval. Holding down the shift key while dragging creates a circle.
• • Add Markers: A marker is a dot with a number. Each dot receives the next available number. Markers permit referencing specific findings by number. (E.g., "The dot labeled '3' shows...") Over the image, hold down the mouse to create and place the marker. Release the mouse to complete the marker placement.
• Aa Add Text: Type into the text box and then click on the image to place the text. Holding down the mouse button permits moving the text; the text is placed when the mouse is released. (If you start typing in the text box, the Add Text button will be automatically selected.)

Managing Annotations

• •⇒ Move annotation element: Click and drag any annotation in the image to repositioning the annotation.
• Y Delete annotation element: Clicking on any annotation in the image deletes the annotation. (If you delete a marker, then the remaining markers are renumbered.)
• U Remove: The last-added annotation element will be removed. Double-clicking this button will remove all annotations.
• ⇓ Download: The current annotated image will be downloaded to your computer. NOTE: The download option is not available on Internet Explorer.
• c Hide Annotations: The current annotations are hidden from view. This permits viewing the image without the annotations. Opening the annotations menu with the A will re-display the annotations.

Accessing Annotations

Currently, annotations are not stored anywhere and are not uploaded to the FotoForensics server. All annotation functionality remains within your web browser. If you close your browser or navigate away from the analysis window, then all annotations will be lost.

Clicking the download button will export the annotated image from your browser to your computer. The downloaded filename is:

fotoforensics-annotate-type_YYYYMMDD_HHMMSS.png
where type is the type of analysis result being shown, and YYYYMMDD_HHMMSS is the current time (year month day "_" hours minutes seconds).

Browser Limitations

This annotation system has been tested on Chrome, Firefox, Internet Explorer, Edge, Opera, Safari, and Chromium. Unfortunately, browser support for annotating images is inconsistent.

• Firefox: The current annotation system works best on Firefox. All colors, drawing tools, and options work as expected.
• Chrome-based: Browsers such as Chrome, Chromium, and Opera work as expected. However, the download button may not prompt the user for saving the file. With Chrome-based browsers, the picture is immediately stored in your download file directory; some browser may not notify the user of the download. (This is different from Firefox, where the user is prompted for saving the annotated picture before it is saved to the download file directory.)
• Edge: The current annotation system works well on Microsoft's Edge browser. All colors, drawing tools, and options work as expected.
• Internet Explorer: Microsoft's Internet Explorer (including IE11) has two significant problems:
  1. There is no download button. This is due to a known bug in Internet Explorer (IE) that prevents downloads. Unfortunately, Microsoft has decided to not fix anything in IE that isn't a security vulnerability, so this bug will not be fixed. If you must use IE, then the only options to save annotations are to either take a screen capture or print the page to a file.
  2. Drawing arrows does not add the arrowhead until after the line is placed. Microsoft has a bug that prevents redrawing arrowheads when creating the line.
• Older Safari: Older Apple's Safari browsers do not support downloads. (Technically, older Safari browsers do not fully support svg images, which is what the annotation system uses.) If you must use an old version of Safari, then the only options to save annotations are to either take a screen capture or print the page to a file. (What is old? 10.6 and earlier fail. 10.12 and later work. But we don't know the exact version cutoff where it began to work.)
• Popups: Downloading the annotated image may be detected by the browser as a popup window. In this event, browser settings that prevent popups may block downloads. You may need to enable popups for the web page in order to save annotated images. We recommend not disabling popups unless you encounter this problem.
• Mobile devices: Mobile devices lack consistency in both supported functionality and user interfaces. (Even if you say you're running Android 2.6.3, your device is likely different from other Android 2.6.3 devices.) Due to these support issues: tablets, smartphones, and other mobile devices are not supported by this annotation system.

Annotations work properly under Firefox, Chrome, Edge, and newer Safari browsers. Most other browsers are either based on Firefox or Chrome, so they should behave like Firefox or Chrome. If you notice any additional problems, please use the contact form. Be sure to specify the browser (type and version), operating system (type and version), and a description of the problem.

Site Version

As an active software project, FotoForensics is regularly updated. Some updates are minor tweaks to the documentation or behind-the-scenes code changes, while others are related to additional functionality or database updates. In general, the core algorithms are not changed. For example, ELA and JPEG % are using the exact same algorithms that the site used when it was first released.

This instance of FotoForensics uses:

Site Revision:	1.1.4875 (2024-11-09)
Analysis Library:	1.2 (Build 10639, 2024-10-17)
Web Server:	nginx
Current Time:	2024-11-21 10:07:36 GMT
Moon Phase:	Waning Gibbous Moon, 73% brightness
Moon View:
Previous Solar Event:	Autumnal Equinox: 2024-09-22 12:43:39 GMT
Next Solar Event:	Winter Solstice: 2024-12-21 09:20:21 GMT