This paper considers the problem of impulse noise mitigation when video is encoded using a SoftCast-based Linear Video Coding (LVC) scheme and transmitted using an Orthogonal Frequency-Division Multiplexing (OFDM) scheme over a wideband channel prone to impulse noise. In the time domain, the impulse noise is modeled as independent and identically distributed (iid) Bernoulli-Gaussian variables. A Fast Bayesian Matching Pursuit algorithm is employed for impulse noise mitigation. This approach requires the provision-ing of some OFDM subchannels to estimate the impulse noise locations and amplitudes. Provisioned subchannels cannot be used to transmit data and lead to a decrease of the video quality at receivers in absence of impulse noise. Using a phenomenological model (PM) of the residual noise variance after impulse mitigation, we have proposed an algorithms that is able to evaluate the optimal number of subchannels to provision for impulse noise correction. Simulation results show that the PM can accurately predict the number of sub-channels to provision and that impulse noise mitigation can significantly improve the decoded video quality compared to a situation where all subchannels are used for data transmission.