brief.instrs

speech signal process tools

			Brief waves+ User Instructions
			------------------------------


MOUSE BUTTON SUMMARY
-------------------

* Region Marking: Left button down, drag through region, release button

* waves+ Function Menu: Right button down in data display

* Colormap Control: Middle mouse button down while in image display

LOOKING AT WAVEFORMS
--------------------

Waveforms displays are single or multi-line displays, in which each display
line consists of points connected by straight segments.


A. The Waveform Window
----------------------
If for some reason the "signal.sd" waveform window isn't up now
(look in the top frame of the display windows for file names),
please bring it up by using the "Input Files" button. "signal.sd"
lives under the "Real signal" button.

The waveform window is a waves+ signal display window.  All such
windows have three important components:  (1) the window titlebar and
frame around the outside, (2) a narrow scrollbar region just under the
titlebar, and (3) the main display area.

Waveform window titlebars contain a lot of useful information.  For
now, simply notice that it tells you the name of the signal file
and the signal's sampling frequency (8 kHz in this case).


A.1. The Data Cursor And The Left And Right Markers
---------------------------------------------------

Now move the mouse into the display area of the window, and move it
back and forth.  You'll see a thin vertical line which tracks the
mouse.  This is the signal cursor.  The current location in time of
the cursor is shown in the titlebar, and the sample value at the
cursor location is printed in the lower left of the display area.

Move the cursor to the signal location at about .4 seconds. Now holding 
the left mouse button down, move the cursor to the signal location at about
.6 seconds and release the button.  You should see another
vertical line at the point where you depressed the button, and a
third one at the point where you released the button.  These two
lines are the left and right markers.  Their locations in time are
shown in the "L:" and "R:" fields in the titlebar.  These markers
delimit a signal segment that can be played out to a speaker,
stored in a file, deleted, and so forth.  The duration of this
segment, in seconds, is shown in the "D:" field of the titlebar.


A.2. Menus
----------

Many waves+ operations are performed using menus.  As usual, the
window system menu pops up when you click right on the titlebar. 
You should be familiar with most of the choices in this menu.  The
operation of these choices are dependent on your operating system: 
try out some of them and see how they work.  Notice that if you
resize the waveform window the portion of the signal displayed in
the window remains the same: only the size of the display changes.

The other important menu is the waves+ signal display menu.  You can
see this menu by clicking right on any point within the data
display area of the waveform window.  For now, choose a point in
signal.sd at about .5 seconds. Click right, and examine the menu that pops up.

Most of the menu items should be self-explanatory.  Let's try one
out:  the "ZOOM IN" selection.  Clicking right on this item
provides an expanded view of the waveform.  Now take a look at the
scrollbar, just under the titlebar.   The heavy horizontal line
that extends across  a piece of the window has now shrunk. This bar
shows the portion of the signal that is currently being displayed. 
Right click again to recall the menu, and right click a second time
to zoom in again.  The bar is now one half its former size.
 
Move the cursor to one of the pulses (prominant positive peak) in
the signal.  Hold the left button down, and advance to the next
pulse.  Release the button.  You should be able to read the peak
period and repetition frequency from the "D:" and "F:" fields in
the titlebar.  You may need to strecth the window horizontally to 
see the "F:" field. 


A.3. Moving Around
------------------

The portion of the signal displayed in the window can be changed by
clicking any mouse button when the cursor is in the scrollbar area. 
(Remember, the scrollbar region is the one under the titlebar and above
the data display.) Here's how the buttons work:

MIDDLE          Press the middle button anywhere in the scrollbar, and
                the displayed portion of the signal will end up centered
                around the cursor in the scroll bar.  (The entire width
                of the scrollbar represents the entire signal.  So the
                center of the scrollbar represents the middle of the
                signal, the left edge of the scroll bar represents the
                beginning of the signal, etc.)

LEFT            Press the left button anywhere in the scrollbar, and the
                sample of the signal at the cursor in the display area,
                not the scrollbar will move to the left edge of the
                window.

RIGHT           Press the right button anywhere in the scrollbar, and the
                sample of the signal at the left edge will move to the
                cursor location in the display area, not the scrollbar.

Play around with these buttons now, to get a feel for how they
work.  Here are three things to remember:

*       These operations only work when the cursor is in the scrollbar
        region.

*       The left and right buttons have opposite effects: pressing the
        left button and then the right button leaves you looking at
        the portion of the signal you began with.

*       The beginning of the signal can't be moved right of the left
        edge of the window.  Nor can the end of the signal be moved
        left of the right edge of the window.  Try this out.  You'll
        see that the signal moves in the correct direction "as far as
        it can" and no farther.

A.4. Quick Review
-----------------

To review, when the cursor is in the display area of a waveform
window, the left mouse button controls the left and right markers,
and the right mouse button pops up the waves+ menu.  
So what does the middle button do?  If you have audio output, it
plays the portion of the signal between the left and right markers. 
Don't worry about that now, but you may find it useful in other
demos, or while using waves+ to do work.


LOOKING AT IMAGE-STYLE DISPLAYS
-------------------------------

Waves+ has image-style displays also. If you don't have a display
window called "signal.fft.spgm" on your monitor, bring it up by
selecting "Real Spectrum" from the "Input Files" control panel.
This window is called a image window.  It contains the result from
doing an overlapped FFT analysis on the file "signal.sd". It is another 
example of a waves+ signal display window.  Like the waveform window,
it has a titlebar with useful information, a scrollbar, and a data 
display area.  

Move the mouse around inside of the image window, and notice
what happens.  The image window has a cross-hair cursor,
which specifies both time and frequency.  Notice that the time and
frequency location of the cross hair is shown in the titlebar,
along with the left and right marker locations, and the marked
segment duration and "frequency".  (Sometimes the titlebar is not
wide enough to show all this information, in which case the latter
values may get truncated.)

Another thing to note is that the cursor in the waveform window and
the cursor in the spectrogram window move together:  the two
cursors are always at the same point in time in their respective
signals.  In waves+ parlance, the two cursors are "ganged" together
because they are different views of the same object.  (Note the
"OBJECT name" field in the control panel.) Try zooming in on a waves+ 
image display by placing the mouse cursor in the data display part of 
the window, holding the right mouse button down, and slecting "zoom in".
Now try "align & rescale"; that puts the two displays on the same time 
basis and vertically aligns them. 

One last thing. place the mouse cursor in the lower left corner of the
image display ("signal.fft.spgm") and hold down the middle mouse button.
Now, still holding it down, move the mouse curosr up to the right. waves+
give you inteactive control over the colormap.

FOR MORE INFORMATION
--------------------
If you have a copy of the waves+ product, you can learn much more about 
using it by doing the "waves+ Tutorial". If you only have this demo,
try the other buttons the the "waves+ INTRO Demo" control panel. The "Colors"
button allows you to try different colormaps, and the "Menu Changes" button
allows you to interatively modify the waveform and image menus.


( @(#)brief.instrs	1.5 8/7/91 ERL )