Follow

Have I mentioned recently how much I love opus audio encoding?

I just took a rip of a 6 CD set from 1GB of FLAC files (which I'll keep for archival purposes) to 160MB of OPUS files (which I'll keep for listening purposes.)

I went from an average file size of 9.25 MB/track to an average file size of 1.4MB per track.

I took a 6CD set and crushed it down to 1/4 of 1 CD-R worth of data, and most average listeners would never notice a difference, maybe not even side by side.

Show thread

@vanillacherry I rip CDs to FLAC because I have a lot of storage availale, and I like to be able to transcode to various other formats for various purposes, and you get better results transcoding from a lossless format than from a high bitrate lossy format.

My FLAC files for this boxed set worked out to about 1GB. My "high bitrate" opus transcode works out to about 250 MB.

I could probably get it down to 100 MB before I'd even notice a difference in audio quality.

@ajroach42 Favorite tool / setting to convert to opus? Opus-tools works, but needs quite a bit of hand-holding / scripting

#opus

@qwxlea @ajroach42
FFMPEG of course, but CLI so can't recommend to everyone

@tleb @ajroach42 😂 , ok, that is a /lot/ of buttons and levers before something useful rolls out...

You have any scripts on git*? Would be nice to compare output of the different implementations.

I'll stick with opus-tools for now.

@qwxlea @ajroach42
If I remember correctly, a simple *ffmpeg -i input.flac -b:a 192k output.ogg* works well enough.

@tleb @ajroach42 ah, merci, mon amie, that is something even *I* can pull off.

Let the battle of the converters commence!

@tleb @ajroach42 Great fun comparing opusenc and ffmpeg!

function song2opus(){
opusenc --bitrate 64.0 "$1" "${1%.flac}-64.opus"
opusenc --bitrate 128.0 "$1" "${1%.flac}-128.opus"
ffmpeg -i "$1" -b:a 128k "${1%.flac}-ffmpeg128k.opus"
ffmpeg -i "$1" -b:a 192k "${1%.flac}-ffmpeg192k.opus"
}

#ffmpeg is a lot louder then opusenc. Rock (Creedance Cl. Rev.) was better using ffmpeg, Pop (B. Eilish) about the same, The Police also better on ffmpeg.

Next, script some blind testing & more bitrates.

@qwxlea @ajroach42
What is your audio setup? I would be happy to participate in those blind tests, I got a QC35 recently (hope no audiophile is in the room) and I'd like to compare it to my other audio emitters. My UE Megabooms are still going strong and I still feel like their sound is good quality, they made me notice how some speakers were bad multiple times.

@tleb @ajroach42 Great idea! My setup is very simple: a rooted samsung phone for outside and headphones in my laptop's audiojack at home.
For headphones I use depending on the music, Sennheiser, JBL or Jabras. One day I hope to get a decent DAC, but for now it will have to do.

@qwxlea @tleb I just use opusenc. I have a little script:

```
#!/bin/bash
for file in ./*.flac; do
opusenc --bitrate 64 "$file" "${file%.flac}.opus"
done

dir=$PWD-opus-64
mkdir -p "$dir" || exit
cp ./*.png ./*.jpg "$dir"
mv ./*.opus "$dir"

```

But the important bit is just opusenc --bitrate 64 Input.flac output.opus

@ajroach42 @tleb
Simple enough ;-)

Is 64 enough, though? From the man-page: The default for input with a sample rate of 44.1 kHz or higher is 64 kbit/s per mono stream and 96 kbit/s per coupled pair.

More encoding battles shall ensue!

@qwxlea @tleb I do a 128 and a 64, each has a separate purpose.

The 64 is for low storage devices and our intranet radio. The 128 is for my regular listening. I could probably get away with 96k, though.

Listen to them side by side, make the determination for yourself.

@ajroach42 6 CDs down to 1GB of FLAC is impressive itself. I never get that kind of ratio with FLAC.

Sign in to participate in the conversation
R E T R O  S O C I A L

A social network for the 19A0s.