This piece of music by Oscar Lorenzo Fernández [1897-1948] is from Suite Brasileira No. 1. The suite consists of the following pieces: 1. Velha Modinha (Old Song), 2. Suave Acalanto (Sweet Sleeping Song) and 3. Saudosa Seresta (Regretful Serenade).
Pictures of settings concerning the sound of the music in the video: