Live 5 .mp3 support and "decoding cache"

proggybreaks · Post by **proggybreaks** » Thu Jul 28, 2005 7:18 am

I just found about about the "decoding cache" folder that Live 5 uses. My understanding of this is that Ableton stores decoded audio files such as .mp3 or .ogg in this folder and then can access them any time they are pulled back up. So I'm wondering, isn't the cache space that the decoded audio file is going to take up going to be almost as much as a .wav anyway? So what's the advantage of using a .mp3 file?

Maybe I'm not understanding it quite right and somebody could shed some light on this.

SimonPHC · Post by **SimonPHC** » Thu Jul 28, 2005 7:38 am

Well, MP3 support is there due to popular demand.
But because timestreching and decoding mp3 doesn't work at the same time, Ableton uses a temporary folder where all you mp3's you use are converted to wav.

yes it takes some disc space. But the files get overwritten or deleted. I mean, it is not a safe folder where everythings stays put, it gets flushed from time to time.

so instead of having 200GB worth of wavs, you have e.g. 20GB worth of mp3's and 10GB decoding cache...

zekrab · Post by **zekrab** » Thu Jul 28, 2005 7:38 am

To use mp3 and ogg, Live needs to decode files to WAV which are put in the cache folder. You can set the size of this cache folder in the preferences.

DJALEX · Post by **DJALEX** » Thu Jul 28, 2005 6:48 pm

SimonPHC wrote:Well, MP3 support is there due to popular demand.
But because timestreching and decoding mp3 doesn't work at the same time, Ableton uses a temporary folder where all you mp3's you use are converted to wav.

yes it takes some disc space. But the files get overwritten or deleted. I mean, it is not a safe folder where everythings stays put, it gets flushed from time to time.

so instead of having 200GB worth of wavs, you have e.g. 20GB worth of mp3's and 10GB decoding cache...

Ok what about if i wanna decod the 20 GB of mp3 to be ready my tour??!!

to me the mp3 and the decoding doesnt make sense, if the file in mp3 is going to be convert to wav " JUST TEMPORARLY" i prefer to convert all my mp3 files to wav, to save the warp inf.
What about if you are playing live, and you drop one mp3 song o sample in the fly!!, and the decoding folder deleted or overwritt that file?? before??!!
Hope you can understan my poor english but Live and the Mp3 function sucks.

robtronik · Post by **robtronik** » Thu Jul 28, 2005 6:55 pm

everything will still work. There shouldn't be any worry here as all it does it create the cache for the ones being used. If your files are short in length, it shouldn't have an impact at all. I have full length tracks (as I DJ) and it hasn't affected the performance or availability of tracks in any way...

At first I thought the same thing but then it has really turned out to be a non issue.

rob.

zekrab · Post by **zekrab** » Thu Jul 28, 2005 7:04 pm

DJALEX wrote: to me the mp3 and the decoding doesnt make sense, if the file in mp3 is going to be convert to wav " JUST TEMPORARLY" i prefer to convert all my mp3 files to wav, to save the warp inf.

Don't worry, all the warp infos are stored when you save them(in the clip window)...even if the cache folder is cleared.
I agree it's really not an issue.
When preparing my radio show, playing directly mp3s saves me:
-HD space!
-1 hour per week to convert to Wav
-1 hour to warp songs

But if you need loops on the fly and can't wait for Live to decode mp3, the best way is to convert them to Wav like before...

Livewire · Post by **Livewire** » Thu Jul 28, 2005 8:15 pm

hey ableton there is this program called virtual dj from atomix. its so cool, you can totally scratch and time-stretch mp3 songs the second you drop it in. and it generates the waveform in the background, kind like what live lets you do with wav files.

i dont think atomix converts the files to wav though? how could it if it lets you play the file right away? well what i'm trying to say is that if atomix can let you time-stretch and even scratch mp3s like vinyl, why cant live?

Hedroom · Post by **Hedroom** » Thu Jul 28, 2005 8:15 pm

I've noticed a BIG problem

Sometimes when decoding the mp3s the wavs rendered in the decoding cache have sizeable glitches EVEN WHEN THE ORGIGNAL MP3 IS GLITCH FREE. erk!

So suddenly all your finely tuned warp settings are out because the new decoded version isn't the same as the one you warped from.

Quite a worrying bug. Not sure I trust letting it decode my mp3s on the fly at the moment. Think I'm gonna have to stick to converting all my mp2s to wavs

Post by **Alex** » Thu Jul 28, 2005 8:20 pm

Hi Splashmas,

you should better make a separate post in the 'Bugs and problem' forum.

regards,
Alex

kabuki · Post by **kabuki** » Thu Jul 28, 2005 8:23 pm

Livewire wrote:hey ableton there is this program called virtual dj from atomix. its so cool, you can totally scratch and time-stretch mp3 songs the second you drop it in. and it generates the waveform in the background, kind like what live lets you do with wav files.

i dont think atomix converts the files to wav though? how could it if it lets you play the file right away? well what i'm trying to say is that if atomix can let you time-stretch and even scratch mp3s like vinyl, why cant live?

Just a guess here, but Atomix (and Tractor DJ, etc) are limited to TWO tracks at a time. Live gives you the option of many more than that. Plus a ton of effects and MIDI instruments, etc.

I figure - just a guess - that if you tried to decode say more than 2 (a meager sum to Live), plus a few VST instruments, and run them thru a few effects, Atomix, Tractor DJ and the like would probably show up at your house, kick in the door and shit in your bed.

Live doesn't even fart at that kind of workload.

If the Abs thouoght that limiting its users to 2 MP3 tracks was acceptable, I bet they could have figured out a way to without a cache.

Just a guess

Hedroom · Post by **Hedroom** » Thu Jul 28, 2005 8:29 pm

Alex wrote:Hi Splashmas,

you should better make a separate post in the 'Bugs and problem' forum.

regards,
Alex

Done

Livewire · Post by **Livewire** » Thu Jul 28, 2005 8:49 pm

does it really take so much cpu to decode mp3s in real-time? arent the LAME mp3 encoder, and most commercial encoders, capable of faster than real-time encoding/decoding?

dont stress out about this ableton, its just that i use other mp3 DJ programs and it seems they dont have a problem playing mp3s directly and instantly.

robtronik · Post by **robtronik** » Thu Jul 28, 2005 8:51 pm

Splashmas wrote:I've noticed a BIG problem

Sometimes when decoding the mp3s the wavs rendered in the decoding cache have sizeable glitches EVEN WHEN THE ORGIGNAL MP3 IS GLITCH FREE. erk!

So suddenly all your finely tuned warp settings are out because the new decoded version isn't the same as the one you warped from.

Quite a worrying bug. Not sure I trust letting it decode my mp3s on the fly at the moment. Think I'm gonna have to stick to converting all my mp2s to wavs

I've never had this problem.

But to tell you the truth, I actually encode all my material into FLAC so I get the space savings (50%) while no loss in audio fidelity.

That to me is the best way to do this. I avoid MP3 if possible - but that still doesn't materially affect my observation that I've had no slippage in my warp settings from cached audio files...

Interesting problem... hope it isn't systemic to the program and is an isolated thing.

rob.

proggybreaks · Post by **proggybreaks** » Thu Jul 28, 2005 9:15 pm

So, does it only save hard drive space if you have songs on there that you aren't using in live? For example, if you have 75 full songs in .wav that you want to use in live vs 75 .mp3 files that you want to use in live, should you just stick with .wav for better sound quality?

Livewire · Post by **Livewire** » Thu Jul 28, 2005 9:43 pm

proggybreaks wrote:So, does it only save hard drive space if you have songs on there that you aren't using in live? For example, if you have 75 full songs in .wav that you want to use in live vs 75 .mp3 files that you want to use in live, should you just stick with .wav for better sound quality?

yes because live is going to convert the files back to wav anyways.