Verifile is a solution to the issues of reliability that have plagued critical recording projects ever since the adoption of computer recording of audio. Typically, general purpose computers whether Mac, PC or other OS, are designed to perform a wide range of simultaneous tasks of which audio recording is just one. Even if the user would like audio recording to be given top priority, the computer’s operating system is not designed that way, and (even if optimally configured, which they seldom are) it will, now and again, interrupt audio recording to do something else. This is especially true when dealing with many channels of high resolution audio, perhaps with low latency, which needs a continuous high data throughput. The result is usually a recorded ‘dropout’ of some kind: anyone who has recorded audio on a computer is familiar with repeated or missed samples or entire sections, random clicks, pops – even channel swapping.
Verifile is a ‘fragile steganographic’ process which embeds derivative data within the dither of the ADC, containing a rolling hash code which allows the audio data to be thoroughly and continuously checked. Recovery of this data from the audio stream or file enables verification that the stream or file contains exactly the audio data that was produced by the ADC at the time of recording. Any incorrect samples, missing or repeated audio segments or any other audio errors in the resulting files can be reliably detected, providing complete confidence that the recorded file is error-free.
Processing of any kind of a Verifile recording such as EQ, level changes, additional re-dithering, sample-rate conversion etc will result in a failure to decode the rolling hash code in the dither and hence indicate that the recording is not an original.