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Of special importance is the SHA-1 data, which is unique for any given audio file. It is a cryptographic hash consisting of a 40 digit hexadecimal number which is essentially a unique fingerprint of the entire audio file. This number is a good way to tell if one file is identical to another file. Thus, it can be useful in Forensics audio work to uniquely identify a file or to detect a file that has been tampered with. That hash number is always calculated over the entire file regardless of the selected area or the channels selected. If even just one audio sample of a file is modified, it will create a different SHA-1 hash number. For example, if you bring up the Demo Wave file called “Male Voice Test Sentence BW” and compare it to “Male Voice ID Test Sentence High Quality” they will sound the same and have the same length and other attributes. However, the first one has one sample edited compared to the other and thus they yield completely different SHA-1 values (proving that they are not identical).
Note: The Waveform Statistics function responds to the channel selected except for the SHA-1 hash (which is always calculated for the entire file, including both channels). When both channels are selected, it responds to the sum of the two (except for SHA-1).
Selected File Portion for Waveform Statistics Analysis
Of special importance is the SHA-1 data, which is unique for any given audio file. It is a cryptographic hash consisting of a 40 digit hexadecimal number which is essentially a unique fingerprint of the entire audio file. This number is a good way to tell if one file is identical to another file. Thus, it can be useful in Forensics audio work to uniquely identify a file or to detect a file that has been tampered with. That hash number is always calculated over the entire file regardless of the selected area or the channels selected. If even just one audio sample of a file is modified, it will create a different SHA-1 hash number. For example, if you bring up the Demo Wave file called “Male Voice Test Sentence BW” and compare it to “Male Voice ID Test Sentence High Quality” they will sound the same and have the same length and other attributes. However, the first one has one sample edited compared to the other and thus they yield completely different SHA-1 values (proving that they are not identical).
Note: The Waveform Statistics function responds to the channel selected except for the SHA-1 hash (which is always calculated for the entire file, including both channels). When both channels are selected, it responds to the sum of the two (except for SHA-1).
Selected File Portion for Waveform Statistics Analysis