Proposal Vertical Scale GUI Improvements

=Subproposals in this proposal=
 * 1) Left & Right channel labelling in Vertical Scale
 * 2) Values for negative signals to be displayed in "Waveform (dB)" view
 * 3) Additional Vertical Scale at right hand end of waveform

=Left & Right channel labelling in Vertical Scale=

The Problem
The Audacity Meter Toolbar clearly labels the left and right channels with simple L & R labels, however the Audacity waveform is not labelled meaning that the user must infer the waveform channels from the labelling on the meters or work on the assumption that we are using the recording industry "standard" of left above right. This can create confusion which we can avoid with simple labelling.

Users should not need to guess, infer or interpolate information which can clearly be given at the outset.

Proposed Feature
For Stereo tracks upgrade the Vertical Scale to include simple L and R labels

Developer/QA Backing

 * Peter Sampson - I favor Option 1 (vote +1) or Option 3 (vote +0.75)

Use Cases

 * User may not make the connection between the meter labelling and the displayed stereo waveform.
 * User has elected to use vertical metering in which case there is no meters/waveform correlation.
 * User may be unaware of the industry (unwritten) convention that left channel is on top in a stereo pair.

Details
Three alternative possibilities are shown in the GUI Examples below.

Option 1

 * Place the L & R labels to the left of the 0.0 in the Vertical Scale
 * This would require a small horizontal expansion to the Vertical Scale box and places the L & R labels to the left of the 0.0 in the Vertical Scale
 * This will cost a little of the waveform screen real estate but at most this should be around 0.2 seconds at normal zoom level

Option 2

 * Replace the 0.0 numbering in the Vertical Scale with a single digit 0
 * The L & R labels can then be placed to the left of the 0
 * This requires no expansion of the vertical scale

Option 3

 * The L & R labels to be displayed in a large gray font underlying the black 0.0 in the vertical scale
 * This requires no expansion of the vertical scale

Option 2
Note: the red circles are not intended as part of the proposed GUI display, they are there merely to identify the labels. Ed 28Dec11: +1; note also the font size of the pictured labels is not intended to reflect reality, nor is the exact (off-center) location--it was a very quick drawing.

Previous Feature Requests relating to this proposal

 * L and R channel labelling on vertical scale (2 votes) (this allows that there were about two -0.5's on the Forum)

=Values for negative signals to be displayed in "Waveform (dB") view=

The Problem
In the "Waveform dB" view of the waveform there is no value labelling displayed in the Vertical Scale for the negative signals drawn on the bottom half of the waveform display.

Proposed Feature
Values for negative signals to be displayed in "Waveform (dB") view.

Developer/QA Backing

 * Steve Daulton
 * Gale Andrews

Use Cases
Quote from forum: "I think that what a lot of users would find useful is an option to display the "normal" waveform view with the vertical scale units displayed in dB"

Details
Value labelling to be provided in the Vertical Scale corresponding to the lower half of the waveform where the negative signals are displayed.

As stated in the original feature request for this: "the obvious issue is how to present that when the scale values themselves are mostly negative".

Previous Feature Requests relating to this proposal

 * Add scaling for negative samples in Waveform (dB) view (4 votes) (the obvious issue is how to present that when the scale values themselves are mostly negative)

=Additional Vertical Scale at right hand end of waveform=

The Problem
It can be difficult to properly assess the magnitude of the signal level at the right hand end of the waveform display.

Proposed Feature
A second Vertical Scale to be placed at the right hand end of the waveform display.

Developer/QA Backing

 * Greg Kozikowski
 * Peter Sampson

Use Cases
Users on the forum report that it is difficult to ascertain the magnitude of the signal level at the right hand end of the waveform display.

Details
A copy of the existing vertical scale to be redrawn at the right hand end of the waveform. At normal zoom levels this would lose us around 0.4 of a second of the waveform display.

Optionally: this could be made switchable on/off by a new option in Preferences>Interface, with the default set to "off" so that current behavior obtains unless and until the user select the additional Vertical Scale.

Previous Feature Requests relating to this proposal

 * Additional vertical scale at right hand end of waveform (1 votes) (this allows that there were about two -0.5's on the Forum)

The following Feature Requests in the Wiki whilst not directly bearing on the sub-proposal here do however have some bearing on the problem statement:

Waveform Grid lines: 
 * Horizontal: (9 votes)
 * Helps alignment with a specific level on the vertical scale when working at the other end of the track (5 votes)
 * Headroom lines at user-specified dB below and above 0dB FS. (1 votes)
 * Gives compliance with SMPTE and EBU standards calling for specified amount of headroom before full-scale clipping.
 * Horizontal and vertical: (4 votes)
 * Turned on and off on the fly, to help with aligning audio and setting levels.
 * Fixed number of vertical lines on the screen - about 30 (or user could chose a number).
 * Zooming should retain the number and pixel distance spacing of the gridlines.