The Music

Is this the documentary-style movie where someone tells the tale of a person lost in the alps in the snow, and sounds his "hunting horn", and there is a response from the "cow-bells", and the guitarist/composer copies the melody on his guitar? Beautiful scenery of the river (barges/salt-trade/etc)?? The origins of "Silent Night" are fairly well set out in Wikipaedia etc. However, I'd like to be able to identify the beautiful TV Movie I've seen only once, and this may be the one.