1. A device, comprising: a processor; a memory, wherein the memory includes: a noise spectral estimator to calculate noise spectral estimates from a sampled environmental noise; a speech spectral estimator to calculate speech spectral estimates from a input speech signal, wherein the sampled environmental noise is not noise present in the input speech signal; a formant segmentation module configured to detect local minima in the speech spectral estimates and to define a formant as a spectral segment between two local minima, wherein the formant segmentation module is further configured to detect local minima in the speech spectral estimates by balancing the speech spectral estimates, differentiating the balanced speech spectral estimates, locating sign changes from negative to positive values in the values of the differentiated balanced speech spectral estimates, and marking the locations of the sign changes as local minima, wherein balancing the speech spectral estimates comprises computing a smoothed version of the speech spectral estimates and subtracting the smoothed version of the speech spectral estimates from the speech spectral estimates; a formant signal to noise ratio (SNR) estimator to calculate a set of formant-specific SNR estimates using the noise spectral estimates and speech spectral estimates within each formant detected in the input speech signal, wherein the formant SNR estimator is configured to calculate each formant-specific SNR estimate in the set of formant-specific SNR estimates using a ratio of speech and noise sums of squared spectral magnitude estimates over a critical band centered on a formant center frequency, wherein the critical band is a frequency bandwidth of an auditory filter; and a formant boost estimator to calculate a set of formant-specific gain factors from the set of formant-specific SNR estimates and to independently apply the set of formant-specific gain factors to each formant detected in the input speech signal such that the resulting SNR within each formant reaches a pre-selected formant-specific target SNR value.