README.md

aplay+ 🎶

a simple BitPerfect player

💿 Supported file formats

• FLAC (Free Lossless Audio Codec)
• WAV (RIFF waveform Audio Format)
• MP3 (MPEG-1 Audio Layer-3)
• Ogg Vorbis
• AAC (mp4/m4a)

🔧 How to build

• build with Colab   

# dnf install alsa-lib-devel
$ make

🌸 How to use

$ make
$ ./aplay+ -h
Usage: ./aplay+ [options] dir

Options:
-h                 Print this message
-d <device name>   ALSA device name [default hw:0,0 plughw:0,0...]
-f                 Use 32bit floating
-r                 Recursively search for directory
-x                 Random play
-s <regexp>        Search files
-t <ext type>      File type [flac mp3 wma...]
-p                 Tuning for Linux platforms

$ ./aplay+ -rx .
$ ./aplay+ -rx -d hw:7,0 /Music/ -s ZARD
$ ./aplay+ -rfx -d hw:7,0 /Music/ -s '^(?!.*nstrumental).*$'

🌟 Tuning for Linux platforms

• Disk I/O

vm.dirty_ratio = 40
vm.dirty_background_ratio = 10
vm.dirty_expire_centisecs = 3000
vm.dirty_writeback_centisecs = 500

#dev.hpet.max-user-freq = 3072

vm.overcommit_memory = 1

sysctl -p

• scheduler

#!/bin/sh
#cat /sys/block/sd*/queue/scheduler
for FILE in /sys/block/sd*/queue/scheduler
do
	[ -f $FILE ] || continue
	echo -n none > $FILE
done

# scheduler for non rotational, SSD
ACTION=="add|change", KERNEL=="sd[a-z]|mmcblk[0-9]*", ATTR{queue/rotational}=="0", ATTR{queue/scheduler}="none"
# scheduler for rotational, HDD
ACTION=="add|change", KERNEL=="sd[a-z]", ATTR{queue/rotational}=="1", ATTR{queue/scheduler}="bfq"

fstrim -v /

• Setting CPU clock to performance

#!/bin/sh
#cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
for CPUFREQ in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
do
	[ -f $CPUFREQ ] || continue
	echo -n performance > $CPUFREQ
done

• Timer

#cat /sys/devices/system/clocksource/clocksource0/current_clocksource
echo tsc > /sys/devices/system/clocksource/clocksource0/current_clocksource

ulimit -a

📖 References

• https://github.com/nothings/stb
• https://github.com/mackron/dr_libs
• https://github.com/dr-soft/mini_al
• https://github.com/ccxvii/minilibs
• https://github.com/jibsen/parg
• https://pulseaudio.blog.fc2.com/blog-entry-1.html
• https://kazuhira-r.hatenablog.com/entry/2021/05/22/210532