17. A computing device that segments phone labels to reduce misalignments in order to improve synthetic speech when the phone labels are concatenated, the computing device comprising: a processor; a module configured to control the processor to train a set of HMMs using one of a specific speaker's hand-labeled speech data and speaker-independent speech data; a module configured to control the processor to segment the trained set of HMMs using a first alignment to produce phone labels, wherein each phone label has a spectral boundary; a module configured to control the processor to use a weighted slope metric to identify bending points of spectral transitions, wherein each bending point corresponds to a spectral boundary, a module configured to control the processor to correct a particular spectral boundary of a particular phone label if the particular spectral boundary does not coincide with a particular bending point; and a module configured to control the processor to synthesize speech using the phone labels with corrected spectral boundaries.
17. A computing device that segments phone labels to reduce misalignments in order to improve synthetic speech when the phone labels are concatenated, the computing device comprising: a processor; a module configured to control the processor to train a set of HMMs using one of a specific speaker's hand-labeled speech data and speaker-independent speech data; a module configured to control the processor to segment the trained set of HMMs using a first alignment to produce phone labels, wherein each phone label has a spectral boundary; a module configured to control the processor to use a weighted slope metric to identify bending points of spectral transitions, wherein each bending point corresponds to a spectral boundary, a module configured to control the processor to correct a particular spectral boundary of a particular phone label if the particular spectral boundary does not coincide with a particular bending point; and a module configured to control the processor to synthesize speech using the phone labels with corrected spectral boundaries. 18. The computing device of claim 17 , wherein the module configured to control the processor to use a weighted slope metric to identify bending points of spectral transitions further applies the weighted slope metric within context-dependent time windows such that spurious spectral boundaries are not applied to the phone labels.