[FFmpeg-user] Upmixing Dolby Pro Logic audio - still not possible?

Ian Pilcher arequipeno at gmail.com
Mon Apr 6 20:56:33 EEST 2020

On 4/6/20 11:28 AM, Ted Park wrote:
> Do you mean the old DPL, or even DPLII, without the various
> enhancements Dolby put on it to extend patents? If so I think all
> there is to it is doing the reverse operation for the matrixing
> applied to the channels (I don’t think there is any metadata if it’s
> not the IIz, IIx, etc variants.)

Yes. The audio track in question is simply Dolby Pro Logic, not even

> And the matrices have been reverse engineered pretty much to
> perfection so if you really don't want to get a reference decoder
> (which aren’t that expensive, though you might want an empty
> equipment rack handy) you could get the matrix coefficients by
> googling for them and do the math and get the separated channels by
> hand.

Any pointers to guides on doing this would be greatly appreciated.


                  In Soviet Russia, Google searches you!

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