Text Envelope

Thanks, Steve. I added some suggestions to the help text (in red) below.

According to conventions we should have no more than 25 lines of help text or 50 characters per line. The first screen has too many lines - perhaps an answer would be to cut therefrom

If Units are seconds and dB, the example above would mean:
at 2.5 seconds, amplify by -6 dB
at 5 seconds, amplify by -12 dB
at 10 seconds, amplify by -48 dB.

I have not fixed all the lines that are over 50 characters.

I think space permitting it would be helpful to have one or two examples of positive % amplification equivalents e.g. 150% or 200%.

The code comment “;;To avoid problems with these versions use only numbers and spaces” could possibly say “;; To avoid problems with these versions use only numbers and spaces in Intermediate Control Points”.

Actually I’m not sure what the changes in 1.3.14 are that have affected this plug-in. I had not picked this up for possible release noting. Can you point me to it possibly?
http://code.google.com/p/audacity/source/list


Gale

HELP (overview):

This plug-in simulates the behaviour > of > the Envelope tool
using text input rather than mouse / pointer control.

‘Select Function’ allows applying the effect or viewing a
help menu.

Time units may be in milliseconds, seconds, minutes or as a
percentage of the selection (default = seconds).
Amplification units may be in dB or as % (default = dB).

The initial and final amplification levels for the selection
have their own controls, allowing easy linear fading from one
level to another.

Intermediate Control Points are entered as Time/Value pairs.
Example: 2.5,-6 : 5.0,-12 : 10,-48

If Units are seconds and dB, the example above would mean:
at 2.5 seconds, amplify by -6 dB
at 5 seconds, amplify by -12 dB
at 10 seconds, amplify by -48 dB.

Values can be separated by spaces or other > non-numeric
characters such as comma, colon or bracket.

Non-> numeric > text is stripped from the input.



EXAMPLES:

For a linear fade out, set:
Initial Amplification = 100 (%)
Final Amplification = 0 (%)
and no Intermediate Control Points.

For a smooth fade to half volume, try setting:
Time Units = %
Initial Amplification = 100 (%)
Final Amplification = 50 (%)
17 97 : 33 88 : 50 75 : 68 63 : 83 53

or for the same effect using a dB scale:
Time Units = %
Initial Amplification = 0 (dB)
Final Amplification = -6 (dB)
Intermediate Control Points:
17 -0.3 : 33 -1.1 : 50 -2.5 : 68 -4 : 83 -5.4



TIPS:

100% amplification amplifies by 0 dB.
50% amplification amplifies by -6 dB.
25% amplification amplifies by -12 dB.
0% (or empty) amplification results in silence.

Positive time values are from the start of the selection.
Negative time values are from the end of the selection.


Example, to set 50% amplification 1 second after
the start and 50% amplification 1 second before
the end of the selection:
1 50 : -1 50


Time/value pairs are always applied in time order
so an extra time value pair can simply be added
to the end of the Control Point list.
‘1 50 : 2 20’ has the same effect as ‘2 20 : 1 50’.

It is often easiest to first apply the effect with only the
initial and final settings. Use > CTRL > + Z to undo and reapply
the effect with additional Intermediate Control Point pairs
as required.