I want to use a melody as part of the soundtrack in a video I'm making. The melody is taken from Finnish composer Jean Sibelius' Violin Concerto. Sibelius lived from 1865 to 1957, and the Violin Concerto was written in 1904. I can perform and record the melody myself on my instrument, so I'm not using other people's recordings.
But I am uncertain about whether or not the musical composition is in the public domain. I live in Canada, and as I understand it, a work is considered public domain 50 years after the composer's death, so the composition would be public domain in my country. But in Finland, where the composer was born, the work is not public domain yet (70 years after death).
So if I make a video which uses, as soundtrack, my performance of the Sibelius melody, would I be able to own the copyright to the video I make?
And what happens when I upload the video to Youtube, would US copyright laws (which I still can't make sense of) apply to the melody by Sibelius?
And if the melody is not in the public domain, how do I go about using it in my video? (finding and contacting whoever the copyright holder is?)