Martin Braun
4e2da5912b
The 1/4-rate downconverter naively negated the input signals (y = -x) which doesn't work when the signal is at full scale. In particular, signals that are at full negative scale get converted to zeros (even though 2's complement would be to return the same number, although that would also be incorrect). This fix changes it such that the smallest negative value gets converted to the largest positive value. This is not a mathematical correction inversion, but a minor amplitude distortion. However, since we're already at full scale, and thus probably clipping, this is preferable to the incorrect resolution of the regular inversion. Put differently, there is no better value in this case. Original-commit: 8bd982745e6247cf3cf3da52925c65126287428a