skeydan
commented
1 year ago
library(bench)
library(tidyverse)
url <- "http://www.physics.uio.no/pow/wavbirds/chaffinch.wav"
wav <- fs::path(tempdir(), "chaffinch.wav")
download.file(
file.path(url),
destfile = wav
)
mp3 <- av::av_audio_convert(wav, fs::path(tempdir(), "chaffinch.mp3"))
############################ usage ############################
w <- tuneR::readWave(wav)
w
# Wave Object
# Number of Samples: 1864548
# Duration (seconds): 42.28
# Samplingrate (Hertz): 44100
# Channels (Mono/Stereo): Stereo
# PCM (integer format): TRUE
# Bit (8/16/24/32/64): 16
av::av_media_info(wav)$duration
# 42.28
w <- av::read_audio_bin(wav)
attributes(w)
# $channels
# [1] 2
#
# $sample_rate
# [1] 44100
length(w)
# 3729096
length(w)/attr(w, "channels")
# 1864548
m <- tuneR::readMP3(mp3)
m
# Wave Object
# Number of Samples: 1866240
# Duration (seconds): 42.32
# Samplingrate (Hertz): 44100
# Channels (Mono/Stereo): Stereo
# PCM (integer format): TRUE
# Bit (8/16/24/32/64): 16
av::av_media_info(mp3)$duration
# 42.31837
m <- av::read_audio_bin(mp3)
attributes(m)
length(m)/attr(m, "channels")
# 1864548
system(paste("soxi", mp3))
# Duration : 00:00:42.32 = 1866224 samples = 3173.85 CDDA sectors
# ffprobe -show_format
# chaffinch.wav:
# Duration: 00:00:42.28
# chaffinch.mp3:
# Duration: 00:00:42.32, start: 0.025057
# It seems like ffmpeg strips off the superfluous samples
# don't quite get numbers to match though - unless this concerns the end as well:
(sup_samples <- 44100 * 0.025057) # 1105.014
(diff_samples <- 1866240 - 1864548) # 1692
############################ performance ############################
viz_benchmark <- function(df) {
p <- df %>%
mutate(
expression =
forcats::fct_reorder(as.character(expression),
min,
.desc = TRUE
)
) %>%
as_bench_mark() %>%
autoplot(type = "ridge") + theme_minimal()
p
}
compare_wav <- mark(
tuneR::readWave(wav),
av::read_audio_bin(wav),
iterations = 100,
check = FALSE
)
viz_benchmark(compare_wav)
compare_mp3 <- mark(
tuneR::readMP3(mp3),
av::read_audio_bin(mp3),
iterations = 100,
check = FALSE
)
viz_benchmark(compare_mp3) +
theme("void")
############################ error handling ############################
notawav <- fs::path(tempdir(), "iamnotawav.wav")
notanmp3 <- fs::path(tempdir(), "iamnotanmp3.mp3")
# no error!!
nm <- tuneR::readMP3(notanmp3)
# Wave Object
# Number of Samples: 19227264
# Duration (seconds): 435.99
nw <- tuneR::readWave(notawav)
# Error in readBin(con, int, n = 4, size = 1, endian = "little", signed = FALSE) %*% : non-conformable arguments
###
# no error/warning, but correct content is returned
nm <- av::read_audio_bin(notanmp3)
length(nm)/attr(nm, "channels")
# 1864548
av::av_media_info(notanmp3)
# $duration
# [1] 42.28
#
# $video
# NULL
#
# $audio
# channels sample_rate codec frames bitrate layout
# 1 2 44100 pcm_s16le NA 1411200 2 channels
w <- av::read_audio_bin(wav)
(w == nm) %>% sum()
# same here: no warning, but content correct
nw <- av::read_audio_bin(notawav)
length(nm)/attr(nm, "channels")
# 1864548
m <- av::read_audio_bin(mp3)
(m == nw) %>% sum()
As discussed with @dfalbel, this should involve evaluation of the following ideas: