This is easily the best video overview on wavelets I've seen.

I've used wavelet transforms on and off for years for things like image compression, harmonic analysis, and currently brain research, and I've always been somewhat disappointed in the quality of material that's out there explaining how wavelets work and how to use them effectively.

There's a small amount of "abstract math" heavy material but relatively little that's focused on using it for engineering, in contrast to all of the amazing material on Fourier transforms.