----------------------
mhWaveEdit README file
----------------------

mhWaveEdit is a graphical program for editing sound files. It is completely 
free (GPL).

You can find the latest release of mhWaveEdit at:
http://gna.org/projects/mhwaveedit/

The contents of this file is also available inside mhWaveEdit from the help 
menu. 

------------
Installation
------------

 * Unpack the source:                 tar xjf mhwaveedit-1.4.15.tar.bz2
 * Go into the source directory:      cd mhwaveedit-1.4.15
 * Run the configure script:          ./configure
 * Compile the sources:               make
 * Install the program:               su -c "make install"

-----------------
Configure options
-----------------

For most people, just using ./configure without any arguments should work fine, 
but here are some options that the configure-script supports:

--disable-gtk2

  If you have both GTK+ 1.2 and GTK+ 2.0 installed and want to use GTK+ 1.2, 
  specify this option.

--without-portaudio 
--without-sdl
--without-alsalib
--without-oss
--without-jack
  
  Specifying this option will leave out a sound driver, even if 
  it's libs and headers are found.

--without-libsndfile
--without-libsamplerate

  Specifying this option will leave out libsndfile/libsamplerate 
  support, even if the library is found.

--with-libsndfile=prefix
--with-libsamplerate=prefix

  This lets you specify the prefix where libsndfile/libsamplerate is 
  installed if it wasn't auto-detected.

--with-double-samples

  Use double precision floating point numbers for sample processing. If
  you intend to edit 32-bit files, you should enable this. 
  
--without-check-casts

  This option disables the run-time type cast checking. It makes some parts of
  the program faster, but makes it harder to debug.



--------
Starting
--------

To start the program, simply type mhwaveedit. If you want to, you can specify 
files to open on the command line, for example 'mhwaveedit file.wav'.

-----------
Sample view
-----------

The area where you 'see' the contents of the file you are editing, is called 
the 'sample view'. 

In the sample view there is a grey vertical bar called the 'cursor'. The cursor 
follows the sound wave when you play the sound. You can position the cursor by 
clicking with the right (2:nd) mouse button. If you do this while you're 
playing a file, the playing will continue from the new cursor position. You can 
also position the cursor more exact by using the 'Position Cursor...' command 
on the Edit menu.

You can place marks in your file by holding down Ctrl and pressing a number 
from 0 to 9. This will place a mark (green vertical bar) with the same number 
at the current cursor position. You can later make the cursor go to that 
position again by just pressing the number. Setting and jumping to marks can be 
done while playing. To remove a mark, jump to the mark and set it again.

-------
Playing
-------

Playing a file is simple, just load the file and press the play button. The 
green play button plays from the current position. The yellow play button plays 
the current selection, or the entire file if nothing is selected. Stop the 
playback with the stop button (with the red square). 

The playback speed can be varied by adjusting the slider to the far right. 

You can do normal editing while the file is playing.

---------
Recording
---------

Recording is done with 'Record...' on the Play menu, or the Record button (the 
red circle). A dialog box will pop up where you can select what format you want 
to record in. After selecting the format, meters and numbers will appear 
showing info about the volume level of the sound input. 

When you want to start recording, press the "Start recording" button. When 
you've recorded everything you wanted to, press the Finish button and the 
record dialog will disappear and newly recorded sound will show up in a new 
window.

Currently it is impossible to play and record at the same time, so the playback 
will stop when you record.

-------
Editing
-------

You make selections by dragging the mouse over the sample view. You can hear 
what you've currently selected by clicking on the "play selection" button (the 
button with the yellow arrow) or by selecting 'Play selection' from the Play 
menu.

You can use the cursor to refine the selection. Use the 'Selection start at 
cursor' and 'Selection end at cursor' buttons to move the selection starting 
point or the selection end point to the current cursor position. You can also 
drag the selection endpoints using the mouse.

The 'Cut' and 'Copy' functions work like in any other software. 

The 'Paste' function insert the clipboard contents at the cursor position. The 
'Paste over' function works like 'Paste', except that it overwrites the data 
after the insert position. 

The 'Paste mix' function combines the clipboard data with the data at the 
cursor position.

The 'Paste as new' function opens a new window and puts the clipboard contents 
into it. 

The 'Crop' function deletes all parts of the file that are not selected.

The 'Silence selection' function replaces the selected part with silence. To 
avoid clicks, the silent part is a line that meets the wave at the endpoints.

All editing functions work non-destructively, that is, the file you're editing 
isn't actually changed until you save it (the effects also work this way).


-------
Effects
-------

mhWaveEdit has a few simple effects, which are available from the 'Effects' 
menu. 

 * Fade in/out

   This creates a linear fade in or fade out effect.

 * Normalize, Normalize to...

   This amplifies the sound as much as possible without getting clipping 
distortion. The "Normalize to..." item lets you specify which level to 
normalize to.

 * Volume adjust/fade...

   This effect lets you select a starting volume and a ending volume and 
amplifies the selection fading from the starting volume to the ending volume.

   Note that volumes above 100% may cause sound distortion. Use the 'Find top 
volume' to find out the maximum amplification possible without distortion. (You 
can use this for normalizing samples.) 

   By setting starting volume and ending volume to the same value you get a 
simple amplification of the sound. 

 * Convert samplerate...

   This converts the samplerate of the entire file to one you specify. There 
are different methods for doing this, usually the one in the top has the best 
quality but can take longer than the other methode.

 * Convert sample format...

   This converts the sample format of the entire file.

   The 'Don't actually change the data' option can be used if the program was 
wrong about the file's format.

 * Byte swap

   This "byte swaps" the selected part. It can be used to repair damaged files 
where the byte order is wrong. Note that if the sound looks alright but plays 
wrong, you should not use this option, instead you should use the "byte-swap 
output" option in the Preferences dialog.

 * Mix to mono

   This mixes all channels of the file together to a mono sound.

 * Add channel

   This copies the first channel to a new channel in the sound, converting mono 
to stereo etc.

 * Map channels...
   
   With this effect, you can change the number of channels in the file. You can 
also rearrange and add (i.e. mix) channels.

 * Combine channels...

   This effect lets you create a new sound by a linear combination of the old 
channels. This means you can do channel mixing / swapping / balance / panning / 
amplification etc. by entering different values. For example, to swap the left 
and right channel, you select that the new Channel 1 should be 0% of the old 
Channel 1 and 100% of the old Channel 2, and the new Channel 2 should be 100% 
of the old Channel 1 and 0% of the old Channel 2 

 * Speed adjustment...

   This effect changes the speed of the selection. The tone will change as well.
 * Pipe through program...
 
   This effect is for advanced users wanting to pipe raw audio data through an 
external program. The output of the program is read back and replaces the 
processed part. 

mhWaveEdit supports LADSPA effects and can also make use of most of the SoX 
utility's effects. To find the LADSPA plugins the environment variable 
LADSPA_PATH must be properly set up. 

All supported effects can be found by choosing the 'Effects...' menu item. The 
effects are listed with names beginning with [B] for builtin effects, [L] for 
LADSPA effects, and [S] for SoX effects.


-------
Quality
-------

Some notes on sound quality.

The general rule when doing audio editing/processing is to not manipulate the 
data more than necessary and keep an original copy whenever you're processing 
your important files. 

Cut, copy and paste operations move the data around without modifying it, so 
these don't degrade the sound quality. Because of level differences, you may 
get a "step" at the start and end of the inserted part, which can cause a small 
clicking sound. 

The mix paste function doesn't decrease quality, unless the peaks become too 
high and you get clipping. In that case you will get a warning message.

Sound data is normally stored as integer values. Therefore, whenever you 
normalize, adjust volume, decrease sample size or filter a sound, the result 
must be rounded. If you use 24 or 32 bit sample sizes, this is not really a 
problem, but if you use 8 or 16 bits sample size, this rounding causes a 
decrease in quality. 

The quality decrease that the rounding causes can be masked by adding a small 
amount of noise before rounding. This is called "dithering". mhWaveEdit 
supports basic triangular dithering and it's enabled by default. 

By default, mhWaveEdit uses floating-point temporary files for storing 
processed results to avoid rounding until the file is saved.
------------
File formats
------------

Even if mhWaveEdit was originally built for editing wav files, it's also 
possible to load and save in a few other formats. mhWaveEdit always supports 
wav and raw files, but if it's compiled with the libsndfile library, mhWaveEdit 
supports a couple of other formats as well. 

To save a file with a different file format, use "Save as..." and choose a 
format in the file type selection box. 

mhWaveEdit has basic support for mp3 and ogg formats. For this to work you need 
to have LAME installed for mp3 support, and OggDec/OggEnc for Ogg support. If 
you have these programs, you can open and save mp3/ogg files just like any 
other file format.

If mplayer is installed, mhwaveedit can open all formats that it supports, for 
example the soundtrack of a video file. Since mplayer is only a player, these 
files can not be saved back after editing, you have to save the file into a 
supported format.
-----
Files
-----

mhWaveEdit creates a directory ~/.mhwaveedit where it stores configuration 
information. 

The configuration file is called config. It can be hand edited, but the easiest 
way is through 'Preferences' on the Edit menu.

Each mhwaveedit process creates a session file in the .mhwaveedit directory 
called mhwaveedit-session-<pid>-<session>-<state>, where <session> is the 
session ID number and <state> is a character code showing the state of the 
session ('r' for running sessions). 

Temporary files are by default also stored in the ~/.mhwaveedit directory. 
Which directories to use can be set through the preferences dialog. To get the 
best performance, you should have one temporary directory for each local 
filesystem. The temporary files have names of the form 
"mhwaveedit-temp-<pid>-nnnn-<session>". Do NOT open or remove temporary files 
with the same pid number as a currently running mhWaveEdit.

mhWaveEdit checks on startup for leftover temporary files and lets the user 
open them. After opening a crashed session, the files can be saved or thrown 
away.
------------------
Keyboard shortcuts
------------------

F1            Help
F12           Record

Ctrl+(number) Set mark
(number)      Goto mark

Ctrl+P        Preferences
Ctrl+E        Effects

Ctrl+O        Open file
Ctrl+S        Save file
Ctrl+U        Save selection as

Ctrl+C        Copy
Ctrl+X        Cut
Ctrl+D        Delete
Ctrl+V        Paste
Ctrl+Z        Undo
Ctrl+A        Select all

Ctrl+G        Position cursor (Go to)
Ctrl+H        Position cursor at file start
Ctrl+J        Position cursor at file end
Ctrl+K        Position cursor at selection start
Ctrl+L        Position cursor at selection end
Y,U           Move cursor to nearest all-channel zero-crossing
I,O           Move cursor to nearest any-channel zero-crossing

Ctrl+Q        Selection start at cursor
Ctrl+W        Selection end at cursor

+,=           Zoom in
-             Zoom out
>             Zoom to selection
<             Zoom all
Arrow keys    Scroll left/right

<space>       Play/Stop
,             Play from cursor pos
.             Stop
/             Play selection
H,J           Move cursor (and playback) 1/8 of view
K,L           Move cursor one sample
Ctrl+arrow    Move cursor (and playback) half second
(             Play first 3 seconds of selection
)             Play last 3 seconds of selection
-------------
Bug reporting
-------------

If you find a bug or flaw in the program that's not mentioned in the BUGS file, 
report the bug in the bug tracker (see contact info) or mail a bug report 
describing the bug to: magnus.hjorth@home.se

In case of a crash, please do not send me any core dumps. They are huge and 
completely useless to me. Instead, create a backtrace. Backtraces tell you 
exactly where the program crashed.

How to create a backtrace:
1. Enable core dumps: ulimit -c unlimited
2. Run the program:   mhwaveedit
3. Make the program crash. You should now get a file named core or core.1234 in 
the directory you're in.
4. Run gdb with the program and core file: 
   gdb /usr/local/bin/mhwaveedit core | tee backtrace.txt
5. After gdb has loaded, use the command: bt
6. Quit gdb with the command: quit
7. Now you should have a back trace in the file backtrace.txt

-----------
Helping out
-----------

There are plenty of things you can do if you want to help the development of 
mhWaveEdit. 

First of all, look for bugs and report all bugs you find into the bug tracker 
or through e-mail. Sometimes a bug can get overlooked for a long time because 
nobody reports it, so don't be afraid to report bugs that have been there for a 
few releases. You don't have to provide fixes or very detailed information, 
although it helps of course.

Feature requests are also welcome, report them to the mailing list or to the 
bug tracker.

If you speak a language other than English and mhWaveEdit isn't translated to 
your language, you can contribute a translation. To do that, copy the template 
mhwaveedit.pot in the po directory into a new file ll.po, where ll is your 
language code (see 
http://www.gnu.org/software/gettext/manual/html_node/gettext_221.html for a 
list of language codes). 

It's possible to edit po-files by hand, but I recommend a program such as 
poEdit (http://www.poedit.org) for editing translations. 

Note that for those translatable strings that look like "RecordStatus|Paused", 
you should ignore what's to the left and only translate the string to the right 
("Paused" in this example). This convention is there to make it possible to 
translate the same string to different things depending on context. 

After you've filled in all the translations you want (you don't have to 
translate all the strings), mail in the po file to me (see contact info) and 
I'll add it to the next release. 

If a translation is incomplete, you're very welcome to translate the remaining 
untranslated messages and mail them in. Corrections to translations are also 
appreciated, but they may need to be checked with the previous translator 
before including them. 


-------
Contact
-------

For bug reports, translation updates, patches and PayPal donations:
magnus.hjorth@home.se

Project page with bug tracker, mailing list membership:
http://gna.org/projects/mhwaveedit

Mailing list (you must be a subscriber before you can post messages):
mhwaveedit-discuss@gna.org


