help editinf files with audacity

Linux for blind general discussion blinux-list at
Wed Jun 28 05:18:00 UTC 2017

Hi mark, Willem here.
Although one cannot edit mp3 with it directly, I have a console-based 
audio editer called dae.
It is based on ecasound.
Below is a dump of its man page.
If you want it let me know.
Email me on wvdwalt at
Regards, Willem
DAE(1)                                                                                                    General Commands Manual                                                                                                   DAE(1)

        dae -

        dae [<audiofile.wav>]

        Dae currently takes no options.


        Dae  was written to be a simple to use digital audio editor which work well with speech under Linux.  Dae is specifically a console program and should NOT be run from a graphical interface like Gnome terminal. To open a console
        under a graphical based Linux system, try Ctrl+Alt+F2 or any other function key (F1-F6) to login on a pure console.  It was designed to work like a conventional tape recorder with the added features of  removing  and  inserting
        bloks  of  data.   Data  can also be inserted from an existing audio file.  If the record option is chosen when in the middle of a file, the recording is made and afterwards, inserted into the file at the point where the record
        option was pressed.

        Dae is started from a console and takes one parameter, the existing audio file that one wants to edit.  If dae is called without a file name, it creates an empty file called unknown.wav.  dae myfile.wav  will  start  dae,  load
        myfile.wav and start to play the file.  A backup of myfile.wav is made as myfile.wav~ before the file is loaded.  If myfile.wav does not exist, it is created as an empty file containing one second silence.

        The current version of dae works reliably on .wav files, so if you want to edit a .mp3 or .ogg, first convert it into a .wav and use dae on the .wav.  The easiest way to do this, is to use sox with its mp3 and ogg support pack‐
        age installed.  E.G. sox somefile.mp3 somefile.wav To convert the edited .wav back to mp3 use lame.  To convert back to .ogg, use oggenc.

        The file starts to play when it is loaded.  The following keys can be used to navigate back and forth while the file is playing: f1: stop, stops the playback of the file.  f2: play, starts playback at the current position.  f3:
        fast  rewind,  jumps  back  one minute in the audio.  It can be used either while the file is playing or when playback is stopped.  f4: fast forward, jumps forward one minute in the audio.  It can also be used while the file is
        playing or when it is stopped.  left-arrow: rewind, jumps back five seconds in the file and can be used like fast forward and fast rewind.  Note that holding down the left-arrow is not recommended as it  does  not  really  work
        well.   right-arrow:  forward,  toggles  the speed of playback between the normal speed and four times the speed of normal playback.  It can be used while the file is playing or when the file is stopped.  l: Toggles lowering of
        playback speed to 70 percent of normal speed.  This is usefull when marking out small portions of audio.  home: go to start of the file.  If the file was playing when this key is pressed, the file will start  playing  from  the
        beginning.  f12: go to end of file, goes to the end of the audio and stops playback, showing the position in seconds.  Fractions of seconds are also shown.

        w: where am I, shows the current position in the file and can always be used.  The position is shown in seconds with a fraction part.  j: jump to, prompts for a position in seconds and jumps to that position in the file.

        Press  f11 to stop playback and select a file to be inserted.  The pickafile file browser with is part of the kies software, is called up if it is installed.  Use the up and down arrows to select the file you want to insert and
        press enter to start inserting.  If pickafile is not available, you will be prompted to type the name of the desired file.  Note: currently only .wav files can be reliably inserted.  The .wav file that you insert does not  have
        to be in the same format, IE, number of channels, sampeling rate etc.  It would be converted into the format of the file you are editing automatically.  Note that the insertion takes quite long.

        Press f10 to start recording at the current position in the file.  You will now see "recording".  You are now recording from the default selected input audio device which could be a microphone or line in.  While you are record‐
        ing, you have the following options.  f1 to stop recording f2 to resume recording and q to stop recording and take you back to your original file.  After you have pressed q as described above, allow for some time for  the  con‐
        tent to be inserted into the file.  It uses the same routine as for inserting from a file for this task.

        The  following tasks can be performed on a part of the audio file which you are editing: Play a part of the file, remove a part of the file and write a part of a file to an external file.  Before any of these tasks can be done,
        the part of the file you want to work with needs to be identified.  This is done by marking the positions of the start and end of the part you want to work with.  Dae calles the part of the file thus marked, a block.  Press  f5
        to  mark  the  start of the block and press f6 to mark the end of the block.  You do not have to mark the start first, if it is conveniant you can first mark the end and mark the start later.  You must have both a start and end
        position marked before any task can be done which requires a block to exist.  To play the marked block, press f7.  If the block is shorter than ten seconds, the block will be played and you will be returned to the possition  in
        the  file where you were when you pressed f7.  If the block is longer than ten seconds, you will not be returned to that position directly.  You are then able to navigate inside the marked block and can use the navigation keys,
        stop and start.  You cannot mark a block within a block, so you can also not perform any task that require a marked blok.  Press q to get back to the position in the main file where you were when you pressed f7.

Writing a block to an external audio file:
        Press f8 to write the marked block to an external audio file.  For reliable opperation, only write out .wav files.  After pressing f8, you will be prompted for the name of the file in which you want the block  of  audio  to  be
        written.   It is important that you give the .wav extention when you type the file name.  Once the block has been written to the file, you will be returned to the position in the main file where you were before you have pressed

Removing a block of audio:
        Press f9 to remove the marked block.  The block will be removed and you will be returned to the position where you were before pressing f9.  If you were at a position which fell inside the block area when you  pressed  f9,  you
        will be returned to the position where the block started.  After the block has been removed, a block is no longer marked.

        Moving  a  block  of  audio  Currently, moving a block is done using three opperations.  1.  Mark the block.  2.  Write the block to an external audio file.  3.  Insert the external file you have just written out at the desired

        Press q to exit the program.  The backup file and the edited file will be on your disk, but all temporary files will be deleted.  The files you have written out using f8 will also remain on the disk.  Dae does not have an  undo
        feature,  so if you accedentally mess up your file, exit using q and copy the backup file over the one you have edited and start over.  You can also copy the messed up file to another file if parts of the file can be used.  You
        then can copy the backup to the origional file and edit it again, inserting parts of the messed up file after you have written out those parts.  This sounds complicated, but the main thing to remember is that  you  can  recover
        from  an error if need be.  If you have messed up your file, just do not start editing it again before you did something to the backup file because if you just start dae again in this situation, the backup file will be replaced
        with your messed up file and you can lose data.

        Dae requires the scripts catchkey, pickafile  and getterm to be in the execution path.  It also requires various standard UNIX utilities, normally available under any UNIX installation.  It also requires ecasound and python  to
        be installed.  An audio tutorial for dae should have been installed in /usr/local/share/dae/tutorial.  It is called dae_tutorial.ogg and can be played with a program like mplayer.

        pickafile (1) sox (1) aoss (1)

        Dae is Copyright (C) copyright Meraka Institute,
         Meraka,  CSIR,  P.O.  Box 395, Pretoria, 0001, South Africa EMAIL: Willem van der Walt wvdwalt at Web: This program is free software; you can redistribute it and/or modify it under the terms of
        the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.

        This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General  Public  License  for  more

        You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

        For  best  opperation, make sure that you can play multiple audio streams at once.  If you are using a screen reader like speakup, this is important as you might otherwise have speakup and dae fighting over who gets the turn to
        make sound.  If your machine cannot be set up in this way, you can still use dae by turning speakup off using the insert-enter key combination on the numeric keypad.

        Dae can use up to three times the disk space that is taken up by the file you are editing.  The working files are deleted when you exit the program, but the backup file remains.  You must remove that by hand.   Any  files  that
        you have created using f8 write block, also remains.

        Dae does not check for disk space before each operation, so make sure you have enough space.  You can lose data if the disk becomes full during some operations although your backup file should be safe.

        By default, dae uses the device called "/dev/dsp" for both sound input and sound output.  On some machines this might perform poorly and on some machines it might not work at all.  You can try running dae using the aoss program
        to work around this problem.  For example: $aoss dae myfile.wav Alternatively, you can edit the dae file.  At the top of the file, you will find the lines: soundin="/dev/dsp" soundout="/dev/dsp" You can change that  to  another
        device,  for example: soundin="alsa" soundout="alsa" Python version 2.6 and later complains about some of the code used in the ecasound python module, but everything still works without problems.  With python 2.6 you are likely
        to see these errors apon entering and exiting dae.  It is possible to get rid of these errors under python 2.6 and later by compiling ecasound against your installed python.   To  do  that,  do  the  following:  Steps  are  for
        Debean/ubuntu 1.  Install python-dev
            sudo apt-get install python-dev

        2.  Get the source code for ecasound.
            apt-get source ecasound 3.  Change into the directory created by the previous step.  cd ecasound2.2-2.7.0 4.  Configure ecasound to be built for your python:
            ./configure --enable-pyecasound=c 5.  Build and install ecasound:
            make&&sudo make install

        Although dae needs more work, I have used it for a number of years for all my audio editing and had no major problems.

        FUTURE  PLANS  FOR  DAE  Add  support for editing/writing compressed files like mp3 and ogg.  Add a save option where you can save to another file while still editing.  This is currently possible by marking all of the file as a
        block and saving it under another name using write block.  Add support for ladspa and ecasound plugins to be applied on parts of the file and saved as part of the file afterwards.

        Willem van der Walt E-mail wvdwalt at


On Tue, 27 Jun 2017, Linux for blind general discussion wrote:

> Hi all, Mark Peveto here.  Looking for some help with audacity.  I've heard folks sware up and down that it's accessible in Linux, but I sure can't
> figure it out.  I was trying to edit an mp3 file.  I wanted to remove maybe the first 5 or 10 seconds of one.  I hit left bracket to set my left
> boundary, and right bracket to set the right boundry, but when I hit delete, it killed the entire file.  Clearly I'm doing something wrong.  What's the
> trick to file editing like this?
> thanks.
> Mark Peveto
> Registered Linux user number 600552
> Everything happens after coffee!
> _______________________________________________
> Blinux-list mailing list
> Blinux-list at

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