What is the best way to combine mp3 files?

Question

I have many mp3 files that I would like to combine into one file. I used the command line method

copy /b 1.mp3+2.mp3 3.mp3 

but it’s a pain when there are many of them and their names are inconsistent. Time does not seem to be running out either.

Answer 1

As Thomas Owens noted, simply concatenating files leaves several ID3 headers scattered throughout the resulting concatenated file, so time / bitrate information will be terribly wrong.

You will need to use a tool that can combine audio data for you.

mp3wrap will be ideal for this - it is designed to combine MP3 files, without the need to decode + transcode data (which will lead to loss of sound quality), and it will also intelligently handle ID3 tags.

The resulting file can also be divided into its component parts using the mp3splt tool - mp3wrap adds information to the IDv3 comment to allow this.

Answer 2

I know this is an old question, but I have the best answer for you. David’s answer is true that simply concatenating files will leave ID3 tags scattered inside (although this usually doesn’t affect playback, so you can do “copy / b” or on UNIX “cat a.mp3 b.mp3> together.mp3” in the extreme case).

However, mp3wrap is not quite the right tool to simply combine multiple MP3 files into one "clean" file. Instead of using ID3, it actually inserts its own custom data format among MP3 frames (the “wrap” part), which causes playback problems, especially on iTunes and iPod. Although the file will play perfectly if you simply allow them to run from start to finish (because players will skip this bytes other than MPEG), the file duration and bitrate will be reported incorrectly, which will lead to an interruption in the search. In addition, mp3wrap will destroy all your ID3 metadata, including artwork, and will not be able to update the VBR header with the correct file length.

mp3cat itself will create a good file with merged data (better than mp3wrap, for example), but it also splits ID3 tags and could not update the VBR header with the correct merged file length.

Here's a good explanation of these problems and the method (in fact) for combining MP3 files and getting a "clean" end result with the original intact metadata - this command line works on Mac / Linux / BSD, etc. She uses:

• mp3cat to merge MPEG data frames only into a continuous file, then
• id3cp to copy all metadata to the merged file and finally
• VBRFix to update the VBR header.

For the Windows GUI tool, check out Merge MP3 - it takes care of everything. (VBRFix also comes in a GUI form, but it does not complete the connection.)

Answer 3

Use ffmpeg or a similar tool to convert all your MP3 files to a consistent format, for example.

 ffmpeg -i originalA.mp3 -f mp3 -ab 128kb -ar 44100 -ac 2 intermediateA.mp3 ffmpeg -i originalB.mp3 -f mp3 -ab 128kb -ar 44100 -ac 2 intermediateB.mp3 

Then, at runtime, merge your files together:

 cat intermediateA.mp3 intermediateB.mp3 > output.mp3 

Finally, run them through the MP3Val tool to fix any stream errors, encode:

 mp3val output.mp3 -f -nb 

Answer 4

The time problem is associated with ID3 headers in MP3 files, which is not taken into account by your method when copying the entire file.

Do you have a choice language that you want to use or does not matter? This will affect which libraries are available that support the desired operations.

Answer 5

What I really wanted was a GUI to reorder them and output them as a single file

The playlist player does just that, decrypts and transcodes them into a combined MP3. It is designed to create mixed tapes or simple podcasts, but you may find it useful.

(Disclosure: I wrote the software, and I make a profit if you buy the Pro Edition. The Lite version is a free version with several limitations).

Answer 6

MP3 files have titles that you need to respect.

You can use this library, for example, the Open Source Audiovisual Library Project and write a tool around it. Or you can use a tool that understands mp3 files such as Audacity .

Answer 7

If you want something for free with a simple user interface that makes completely clean mp3, I recommend MP3 Joiner .

Features:

• Resets ID3 data (both ID3v1 and ID3v2.x) and does not add their own (unlike mp3wrap)
• Lossless connection (does not decode or transcode .mp3s). No codecs are required.
• Simple interface (see below)
• Low memory usage (uses threads)
• Very fast (compared to mp3wrap)
• I wrote this :) - so you can request functions and I will add them.

References:

• MP3 Joiner website: here
• Last Installer: Here

Answer 8

As David says, mp3wrap is the way to go. However, I found that he did not correct the header for the length of the audio, so iTunes refused to play the entire file, despite the fact that all the data was there. (I combined the three 7-minute files, but only saw the first 7 minutes.)

I dug up this blog post explaining how to fix this, as well as how to copy ID3 tags on top of the source files (in itself, mp3wrap removes your ID3 tags). Or just copy the tags (using id3cp from id3lib ), do:

 id3cp original.mp3 new.mp3 

Answer 9

I would use Winamp for this. Create a playlist with the files you want to merge into one, select the Disk Writer output plugin, select the file name, and you're done. The file you get will be the correct MP3 file, and you can set the bitrate, etc.

Answer 10

I have not heard of mp3wrap before. It looks great. I guess someone got into gui too. But to answer the original post, I wrote gui, which executes the COPY / b method. So, under the covers there is nothing new under the sun, but the program is all about making the process less painful if you have a lot of files to merge ... And you do not want to transcode And each set of files to merge is the same bit. If you have it (and you are on Windows), check out Mp3Merge at: http://www.leighweb.com/david/mp3merge and see what you are looking for.

Answer 11

Personally, I would use something like mplayer with an audio pass, at least an option, for example, -oac copy

Answer 12

Instead of using the command line to execute

copy / b 1.mp3 + 2.mp3 3.mp3

instead, you can use "The Rename" to rename all MP3 fragments into a sequence of names that are in order based on some sort of counter. Then you can use the same command line format, but change it a bit to:

copy / b * .mp3 output_name.mp3

This assumes that you ripped all of these MP3 fragments at the same time and they have the same sound settings. Worked great for me when I converted the audiobook I had in .aa into one .mp3. I had to burn all .aa files to 9 CDs, and then copy all 9 CDs, and then about 90 mp3s left me. Actually a pain in a55.