Is there an easy way to split mp3 files?

Question

I recently learned a neat trick. To join mp3 files together, you simply use the command (in Windows)

copy /b *.mp3 joined.mp3

and voila, you have one large mp3 file.

My question: is there a method of doing the opposite, i.e. splitting an mp3 file, this easily?

Answer 1

There are two ways to split an MP3:

1. Decoding into a wave, splitting, and re-encoding. This is the method Audacity uses and results in lost audio quality.
2. Splitting the MP3 directly. You have a lower resolution for where to split, but the result is no loss in audio quality. I've used MP3DirectCut with relatively good success.

Usually you will want to use the 2nd method since it is lossless, unless you really don't care about your audio quality.

Answer 2

It's not as easy as the command you mention in your question. With that being said there are easy ways to do it.

Audacity is one free program that allows you to split mp3s. It's relatively easy to use once you get a hang of the interface.

Answer 3

I regularly use mp3splt. It is an open source program for Windows and Linux, and includes a gui (which I don't use, so I can't comment on it).

This is the commandline I usually use to split a podcast into 6 minute segments:

mp3splt podcast.mp3 -g %[@N=0,@o] -o "@n @f" -t 6.0

• -t 6.0: split every 6 minutes
• -g %[@N=0,@o]: for every section use the original tags, but update the track number starting from 0.
• -o "@n @f": The output file name should be the original filename with the track number tacked on in front.

Answer 4

Try MP3DirectCut. It's free and works for me.

Answer 5

Not that easily, but there are a number of mp3 splitting tools available online that allow you to pick where to split an mp3 file.

Of course if you wanted to split up an mp3 file just to transfer it (and not to play back the split portions), you could use a generic file splitting utility and then the binary copy method you've used to reassemble the mp3.

Answer 6

If you happen to be using Linux you can always use "split --bytes=1M --numeric-suffixes largefile.mp3 smallfile". However, you will have to append the .mp3 yourself unfortunately.

Answer 7

For the record, that's not the best way to merge MP3s.

It works, but it leaves superfluous information (the ID3 tags) from the subsequent files in the final file. Copy, when used that way, is just a concatenate - the extra header information is still in there.

The structure of an MP3 file can give you an idea:

(Click to zoom)

Answer 8

Sliff is right, no os tool available.

Technically mp3 is configured such that you can split at any place you want. It uses 18 ms block of static or variable length with a certain bit combination at the beginning of each block. If you split the file in midst of a block, the player is just going to forward silently to the next block and you therefore lose a max of 18 ms.

Tag blocks - where you enter information about artist, title, album and such, can be at any place in the file or be ommitted. Even multiple tag blocks do not harm (the first is taken).

You can therefore split and join wherever you want.

Any tool to split files would do then.