Currently the Ranking Criteria touches upon audio bitrate modes without clarifying more specific details that really matter given how users can't really tell the difference.

I feel like we can have something to explicitly cover what types of bitrate modes are acceptable instead of being vague about it for those who do not know, aside from that I don't think anyone who doesn't know about .ogg will bother to use it so it's better to specify which quality is acceptable.

I'm mainly bringing this up since most users will use audacity and plug in an "average" or "variable bitrate" and call it a day but those do not give you the exact 192kpbs which most people use. Given how AIMod is still very outdated but continues to tell users about the bitrate mode, another thing to note is that osu! is not really compatible with vbr/abr since it ends up causing issues with preview points and minor timing issues.

A beatmapset's audio file must use the .mp3 or .ogg file format. MP3s must have a constant bit rate no greater than 192kbps. OGGs must be no greater than 192kpbs (Quality 6)

Vs.

Ranking Criteria wrote:

A beatmapset's audio file must use the .mp3 or .ogg file format and have an average bit rate no greater than 192kbps.

As you can see the current doesn't really inform you about OGG Vorbis but also the current information for audio bitrate modes here are quite misleading.

If you don't believe me when it comes to the average bitrate issue (it's more of a bug I guess but this isn't a bug report) you can take a look at an example that was fixed but never really fully addressed but that's mostly due to standards today when it comes to having "good audio" for ranking:

Lasse's mod on dsco's map of This Charming Man tells him to fix audio bitrate because it's simply over the cap. I never checked if it was changed from a variable bitrate to a constant but I still have the old mp3 and the beatmapset if you want to hear it for yourself: This Charming Man osz with old MP3


edit: holy crap it looks like this is something that was in discussion at community/forums/topics/1123516 ?????????????????????

Either way this discussion was mainly aimed at clearing up confusion for bitrate modes for MP3 audio over OGG Vorbis so discussion is welcome.

BlastTheKidd wrote:

another thing to note is that osu! is not really compatible with vbr/abr since it ends up causing issues with preview points and minor timing issues.

this isn't an issue anymore and it's why the rule is written like this. see community/forums/posts/7188716

I think the other thread will clear up any misinfo about .ogg (which is itself a misleading name to mean Vorbis in this context... I forgot if Opus was even tested when .ogg was originally allowed for songs). either way, this rule could rly use a link to a basic encoding guide

I believe in the fact that the client still manages to mess up VBR/ABR audio at the moment given the example I had shown above but yes, most guides that are accessible through the site are quite outdated so it wouldn't be hard to just conjure one up (specifically for using LAME with Audacity).

ailv wrote:

the wording "average bit rate" encompasses both cbr and vbr files, since cbr will have up to a constant 192.

When people see average I'm pretty sure they jump to the conclusion that ABR is just fine and use that over CBR but given how we have a guideline to tell people to find the highest possible quality, it'd mean that CBR is basically the way to go in this case:

Ranking Criteria wrote:

A song's audio file and hitsound files must be of reasonable quality. Try to find the highest quality source file available rather than ripping a file from a streaming video website. Songs should be normalized to their original release volumes and should not be encoded to a bit rate higher than their original files.

I also want to point out that ABR and CBR are not the same but also not similar to one another. Even though cbr produces somewhat lower quality it's still a constant bitrate and not a variable.