compressng audio

[3390]

i have an audio clip that's abt 1hr45min long. is there any way i can compress it so that it'll fit on a 80min cd? it needs to be made into an audio cd... any inputs appreciated. thanks!

[steptoe]

The simple answer is no

If when you play it the play time is 1hr 45, then thats how long it will always be, unless you cut it into two

Regardless of what you convert it with, it will always be 1hr 45 long


If you convert it to MP3 all you are doing it removing useless data that the encoder thinks you won't miss, but that just reduces the FILE size not the actual playing time

[jimmalenko]

i have an audio clip that's abt 1hr45min long. is there any way i can compress it so that it'll fit on a 80min cd?

No, not possible.

Not unless you speak fluent chipmunk, anyways ...

[gll99]

Any compressed format like mp3, wma etc.. would allow you to put many more minutes on a standard disc, however, what you are asking is if you can fit more than 80 minutes on a standard cd music disc.
The short answer is no because pcm audio (uncompressed cd) is what the time estimate is based on. A 74 minute disc will hold 74 minutes of play time etc...

Having said that....
It should be theoretically possible to lower the bitrate and burn more data (minutes) in the same physical space.
The trick is to find a program that will take lower bitrate files and convert them to cd format without padding the bitrate to compensate. I have never tried to look for such an app nor do I know if it is even possible but you may want to explore that option just in case.

[Supreme2k]

Actually, if it is a mono track, you can put half on one channel (right) and half on the other (left). Then it would just require balancing the sound to one channel, listening to it, then balance to the other channel and replay.

[gll99]

@Supreme2k
That's true the capacity listed for audio discs is based on how much stereo 44.1 kHz 16 bit audio data you can burn on a CD-R.

Recording a separate left and right mono channel would work for sure but again what a sacrifice for the sake of an extra disc. The sounds would play together so you would have to balance one side and then play the track again and slide the balance to the other side.

I don't know if lowering the bitrate to 8 would increase the available space by a factor of 2 but I bet the music would be crappy. Voice would be ok I imagine. I've never tried it so don't know if it has that effect or not or if a conversion/burner program would up the bitrate back to 16.

[jman98]

I don't think the specs for CD audio allow you to lower the bit rate.
You have a couple of options that won't produce an audio CD, but might be worth considering.
1) To make MP3s of it, as already suggested.
2) http://www.vcdeasy.org has a program that can convert audio to MPEG-1 layer II audio and make an audio VCD out of it, giving you something like up to 8 hours of playing time on a CD-R. You have in effect made a photo VCD with a soundtrack where the photo is black space, but it is a possibility if you don't have to have an audio CD.

[SLK001]

If it's not music, then you CAN do this (you can do it with music also, but you may not like the results).

Just load the entire file into a SOUND EDITOR (I use CoolEdit2000, so my technique is based on this program), and apply a "squeeze". If you let the pitch float, it will take a while. If you want to keep the pitch correct, it will take a longer while.

[greymalkin]

yep..if they can understand it at roughly 30% faster than normal speed..you can do it..if it's just speech, you may want to go through and see if there is any dead space you can cut out as well to get the file size as close to 80min before speeding it up.

[Supreme2k]

Pay no attention to these pikers. Use my idea.

Or, spend the extra 3 cents for another CD. You never told us the reason why it needs to go on one CD.

[Nelson37]

Exactly what IS this 1 hr 45 min audio clip, and what do you wish to do with it?

My guess would be this is a concert, in which case you could edit out lots of between-song crowd noise, OR

It is some kind of educational or instructional audio, mostly speech, in which case a speed-up may well be functional.

Also, depending on the intended playback device, many will now handle MP3 files which would be the simplest solution.

More info needed.