Audacity Forum

How I use copy audio copy codec ?
when split one hour and 33 minutes of mp3 .

This is nothing to do with recording techniques, so please repost your question in the correct Forum for your operating system (for example, 1.3.X, Linux). Please explain exactly what you are trying to do, or we can't help you.

You can split a long recording up into separate files using this Tutorial. If you want to use Audacity to export files using FFmpeg, add FFmpeg to your computer using these FFmpeg instructions.

If you are on Windows then after installing FFmpeg as above you can use Audacity to export using the FFmpeg command line. Choose (external program) then click "Options" before exporting. The basic syntax is

ffmpeg -i - "%f"

For more advanced syntax, read the FFmpeg documentation.



Gale

Gale Andrews wrote:This is nothing to do with recording techniques, so please repost your question in the correct Forum for your operating system (for example, 1.3.X, Linux). Please explain exactly what you are trying to do, or we can't help you.

You can split a long recording up into separate files using this Tutorial. If you want to use Audacity to export files using FFmpeg, add FFmpeg to your computer using these FFmpeg instructions.

If you are on Windows then after installing FFmpeg as above you can use Audacity to export using the FFmpeg command line. Choose (external program) then click "Options" before exporting. The basic syntax is

ffmpeg -i - "%f"

For more advanced syntax, read the FFmpeg documentation.
Gale

I am using Linux Fedora 13, I read all this, before post the problem. The thing is I don't see , and can't select audio codec copy .

which is the best technique of export files , when is possible .

If you don't have, you should consider have it.
Thanks,

sergiomb wrote:... split one hour and 33 minutes of mp3 ... which is the best technique of export files

Maybe you are looking for a lossless MP3 splitter ? ... http://mp3splt.sourceforge.net/mp3splt_page/home.php (other lossless MP3 splitters are available).

Splitting the MP3 without decoding-recoding produces a techinically better result : the split files are the same as the original source: no loss of quality.

For mp3 splitting without reencoding on linux I add my vote for mp3splt.

Sergio, I'm not sure if we understand what you are trying to do...
What is your native language? If it's portuguese you can send me a private message in portuguese, explaining your problem.

Trebor wrote:

sergiomb wrote:... split one hour and 33 minutes of mp3 ... which is the best technique of export files

Maybe you are looking for a lossless MP3 splitter ? ... http://mp3splt.sourceforge.net/mp3splt_page/home.php (other lossless MP3 splitters are available).

Splitting the MP3 without decoding-recoding produces a techinically better result : the split files are the same as the original source: no loss of quality.

Exactly what I want. We can do it with ffmeg -acodec copy in command line ...
thought we can use it in audacity or audacity can use it in general
but thinking again is it possible ?
Thanks,

No, audacity will always decode it to "raw" uncompressed audio and if you export to mp3 it will always reencode it again. You can't apply audio effects to compressed data such as in an mp3. mp3 data is not "editable". Data must be decoded/uncompressed so that it becomes again an "audio signal" and then once you apply effects to it the audio is changed and needs to be recompressed again.

Imagine a text file, in its uncompressed format is text that you can read and change de words in it. If you compress it in a zip file you can't no longer read it or edit it while it is in zip format.

bgravato wrote:No, audacity will always decode it to "raw" uncompressed audio and if you export to mp3 it will always reencode it again. You can't apply audio effects to compressed data such as in an mp3. mp3 data is not "editable".

Sergio, it's not likely to happen, but I've added your vote for an Audacity Feature Request to be able to "edit" MP3 natively. Cut-and-paste editing and volume edits can be done, as in MP3 DirectCut for Windows, which also does file splitting. Maybe there is some tool on Linux that can do it as well, but I don't know.


Gale

Gale Andrews wrote:Sergio, it's not likely to happen, but I've added your vote for an Audacity Feature Request to be able to "edit" MP3 natively. Cut-and-paste editing and volume edits can be done, as in MP3 DirectCut for Windows, which also does file splitting. Maybe there is some tool on Linux that can do it as well, but I don't know.

I wasn't aware that volume changes could be done to an mp3 without reencoding... I thought only split/merge actions were possible...

Gale, please add my vote for that feature request too.