Provir

Independent provenance for recorded music. We establish whether a file is what it was sold as.

The problem

A great deal of music sold as lossless is not. It was compressed once, decompressed and repackaged, and the buyer is charged for quality that is no longer in the file.

The industry knows. Distributors tell uploaders, in their own published guidelines, not to submit lossy files converted to FLAC. What nobody ships is a way to check. Every available tool looks for a missing top end, and above about 256 kbps there is not one to find.

The evidence

Provir reads what the encoder left behind in the audio itself. It needs no original to compare against and no metadata to trust.

Independent blind evaluation. Sets built, encoded and scored by an external expert who has never been shown the method.
full-band MP3, 320 kbps23 / 24 identified
MP3, V024 / 24 identified
Ogg Vorbis, quality 826 / 36 identified
genuine masters0 / 36 false positives
eleven other codecs0 / 216 false positives

MP3 and Vorbis are read by two different mechanisms, so neither result depends on the other being right.

Never wrongly accusing a genuine master matters more to us than catching every fake. Our false-positive rate is measured per release rather than per file, which is the stricter of the two conventions.

Who it is for

Listeners and artists, who should be able to check what they bought or what they made without paying for the privilege. And anyone who sells recorded music and would rather find this in their own catalogue than have someone else find it for them.

Status

In active development and not yet publicly available. If you would like to be told when it is, or you audit a catalogue for a living, write to contact@provir.org.