The Collage Aesthetic of Louis Armstrong: “In the Cause of Happiness” (Peter Jay Sharp Arcade, Frederick P. Rose Hall, Broadway at 60th St., up through Sept. 26). Now that a book of Louis Armstrong’s collages has been published, a growing number of music lovers are becoming aware that the greatest jazz musician of the twentieth century was also a gifted amateur artist who decorated the boxes that held his reel-to-reel tape collection and the walls of his New York home with colorful scissors-and-Scotch-tape assemblages of newspaper and magazine clippings whose freely associational quality recalls the “visionary art” of untrained painters. Jazz at Lincoln Center is currently mounting an exhibition of large-scale reproductions of Armstrong’s collages, and a selection of the fragile one-of-a-kind originals will also be on view at the Louis Armstrong House Museum in Queens through July 12. Both shows offer a fascinating glimpse of a little-known aspect of Armstrong’s proliferating creativity (TT).