We present a method, based on the properties of wavelets transforms, for inferring a 3-dimensional and irrotational velocity field from its observed radial component. Our method is comparable in its objective to POTENT but the use of the wavelet analysis offers in addition a robust tool in order to smooth the sparsely sampled cosmic velocity field. The application of our method to simulations permits us to study the influence of the sparse sampling as well as the distance measurement errors. Finally, the potential velocity field within a cube of size 10000 km.s$^{-1}$ and centered on our galaxy is derived from the redshift-distance catalog MARK II compiled by D. Burstein.