I am trying to estimate the signal-to-noise ratio of a wave file (The wave file is a recording of a conversation in a room). I found examples where the Matlab scripts compare the wave file data to a noisy wave file. This noisy wave file is generated by either mixing Gaussian noise into the actual recording or they have mixed other sounds into the wave file and estimate the SNR.
How do I determine the noise floor for calculating SNR of a wave file? The reason for estimating the SNR of the recorded wave files is to determine if the speech content recorded in the file is useful or rendered by useless due to noise in the background.