If you really wanted to do this:
library("audio")
bday_file <- tempfile()
download.file("http://www.happybirthdaymusic.info/01_happy_birthday_song.wav", bday_file, mode = "wb")
bday <- load.wave(bday_file)
play(bday)
Note you'll need to install.packages("audio") first. If you already have a specific file, you'll need to convert it to WAV format first.
If you wanted something a bit more programmery than playing a WAV file, here's a version that generates the tune from a series of sine waves:
library("dplyr")
library("audio")
notes <- c(A = 0, B = 2, C = 3, D = 5, E = 7, F = 8, G = 10)
pitch <- "D D E D G F# D D E D A G D D D5 B G F# E C5 C5 B G A G"
duration <- c(rep(c(0.75, 0.25, 1, 1, 1, 2), 2),
0.75, 0.25, 1, 1, 1, 1, 1, 0.75, 0.25, 1, 1, 1, 2)
bday <- data_frame(pitch = strsplit(pitch, " ")[[1]],
duration = duration)
bday <-
bday %>%
mutate(octave = substring(pitch, nchar(pitch)) %>%
{suppressWarnings(as.numeric(.))} %>%
ifelse(is.na(.), 4, .),
note = notes[substr(pitch, 1, 1)],
note = note + grepl("#", pitch) -
grepl("b", pitch) + octave * 12 +
12 * (note < 3),
freq = 2 ^ ((note - 60) / 12) * 440)
tempo <- 120
sample_rate <- 44100
make_sine <- function(freq, duration) {
wave <- sin(seq(0, duration / tempo * 60, 1 / sample_rate) *
freq * 2 * pi)
fade <- seq(0, 1, 50 / sample_rate)
wave * c(fade, rep(1, length(wave) - 2 * length(fade)), rev(fade))
}
bday_wave <-
mapply(make_sine, bday$freq, bday$duration) %>%
do.call("c", .)
play(bday_wave)
There's a few points to note. The default octave for the notes is octave 4, where A4 is at 440 Hz (the note used to tune the orchestra). Octaves change over at C, so C3 is one semitone higher than B2. The reason for the fade in make_sine is that without it there are audible pops when starting and stopping notes.
