pHash is an implementation of various perceptual hashing algorithms. A perceptual hash is a fingerprint of a multimedia file derived from various features from its content. Unlike cryptographic hash functions that rely on the avalanche effect of small changes in input leading to drastic changes in the output, perceptual hashes are "close" to one another if the features are similar. Potential applications include copyright protection, similarity searches for media files, or even digital forensics.
AudioScout is a distributed audio content indexing system. It can index a large collection of audio content for the purpose of later recognition of unknown signals. Robust to noise, different encodings, and other types of distortion, it can be used for a variety of applications including duplicate detection of files, identifying music, as well as more sophisticated uses involving the enforcement of copyrights and ensuring lawful use of content.
Sorry about that. It may have been down for maintenance at that time, but it is functioning properly now.