In this paper, various regularizations on the room impulse response
(RIR) are proposed to obtain better single-channel speech derever-
beration in the non-negative matrix factorization (NMF) framework.
The regularizations on the RIR are motivated by the spectral domain
representation of the RIR. To obtain better estimates of the RIR and
clean speech, we propose three modifications (i) to obtain a sparse
RIR (ii) a frequency envelop constrained RIR and (iii) to include the
early part of the RIR. The performance of the proposed regularizers
are evaluated by considering speech enhancement measures. While
it is observed that the regularizers lead to an improved estimate of
the RIR, they do not necessarily lead to speech enhancement in all
the cases. For the experiments conducted using the RIRs from the
REVERB 2014 challenge and sentences from the TIMIT database,
the regularizer that includes the early part of the RIR shows reason-
able improvement in speech enhancement measures.