Digital image authentication is essential to determining whether the evidence presented is authentic or has been altered in some way. When altered, images don’t portray an accurate representation of the events as they occurred. Authentication will determine whether the image is original and if not how it has been modified.
Before we begin the process, we will perform an initial analysis. This initial analysis allows us to review the evidence in depth and determine if there are signs of tampering or red flags we need to investigate. This allows us to learn more about the image(s) before proceeding to more costly and detailed forensics testing.
The goal of digital integrity verification testing is to authenticate the digital integrity of the format of the image evidence. In simpler terms, this process involves us examining the digital information embedded within the image. From the embedded information we can determine if it is consistent with what we would expect to see from an original image. We are able to determine if the produced image was created by the system as a 1st generation copy.
We also perform a 4-part digital information test that analyzes camera specifications of the image. The information we analyze may include footprints of photo editing software that were used to manipulate the digital image, such as Photoshop. This test can also identify malicious edits and tampering.
If cloning or copying methods of physical images are used, a loss in quality can be scientifically observed and documented. We are able to detect quality loss through digital image conversion to several formats (JPEG, BMP, TIFF, PDF and more).
If a digital image isn’t of sufficient image quality due to image compression, the digital image will lack authenticity. Essentially, it lacks the necessary criteria to make an accurate identification of a suspect, vehicle or other object. This is why authentication is so important, it determines whether the image evidence can be shown as authentic in court.