Societies have long recognized the importance of being able to encode information in a way that ensures only authorized parties have access to the encoded information. This recognition has led to the development of cryptographic techniques which have been used to secure sensitive information for centuries. Information security is especially important in modern societies having economies and institutions that place substantial reliance on information that is stored digitally. Indeed, in many cases, entire transactions, relationships, and events are defined by information that is stored only in digital form. Such information includes not only textual documents, financial data, and the like, but also includes multimedia content such as audio, visual, and audiovisual content. In many cases, if digital assets such as these were to be lost or compromised, the financial and human toll would be substantial. In particular, for a digital asset that has no analog equivalent, once all copies of the asset are lost or compromised, the asset is unrecoverable. Applying robust cryptographic techniques to the storage and transmission of digital assets reduces the likelihood of intentional or unintentional data corruption going undetected, and is therefore often considered to be critically important in modern digital societies.
To provide one example, in the field of criminal law prosecutors and defendants alike often rely on audiovisual evidence. For instance, a security camera or body camera may generate a video recording, stored in digital form, that provides evidence of a suspect's guilt or innocence. But the video recording will be largely useless to prosecutors and defendants alike if its contents are subject to manipulation by unauthorized parties. And in many cases the video recording may contain sensitive information that should not be subject to public release, for example to protect a victim's privacy. To date, efforts to secure audiovisual evidence have focused on physically securing the devices and media used to capture and store the evidence, respectively.