MITSYN Waveform File Play-Record-Edit
The MITSYN Waveform File Editor supports the viewing/editing of waveform stream files. All the usual viewing (zooming), playing, recording, and editing (cropping, splicing, fading in or out, applying effects such as adding reverberation and filtering) operations are supported. Several types of spectral analysis views are available. Locations or events within waveforms may be marked in label lists.
A screenshot of the MITSYN Waveform File Editor is shown at the below. 
The "cursor" is shown
by a vertical yellow bar in each view. The "current selection" is shown as a shaded segment
in the top pane. Additional floating windows may be shown to view the waveform of the current selection
(i.e., zoomed in to the selection), a spectrum of the waveform at the cursor, and a
spectrogram of the current selection. The showing
of these data windows windows may be turned on/off from the View menu or by using the toggle
buttons following the Wnds label in the view toolbar.
Spectral analyses may be viewed in both single spectrum and spectrogram format, with adjustable analysis parameters such as window size (transform length) and spectral smoothing options. Spectrogram views may be either gray scale, or colored.
Tooltips
A primary component of usage information consists of help balloons called "Tooltips" which popup when the mouse cursor is hovered over each control (button, slider, scroll bar, textbox, music keyboard, etc.) of the many toolbars. To learn what any control does, or find the interpretation of graphics and readouts, hover the mouse cursor over the item, and a tooltip will popup which describes the function of that item. This is particularly relevant for the many "sliders" and dynamic readouts on the toolbars, since giving them static labels would waste screen space. If a shortcut key is assigned to the command activated by the control the key(s) will also be shown at the end of the tooltip.
Editing Operations
Many editing functions operate on the "currently selected segment". The easiest way to select a segment is to click and then drag through the desired range, exactly as you would select a segment of text in your word processor. Other common selection actions include the dragging of either end of the selection, and the Edit→Select All command (shortcut key Ctrl+A). Choosing the top level "Help" command shows all of the click/drag options. The currently selected segment is shown with a light yellow shading.
Some editing operations can be applied to either the "current channel" or to all channels. The current channel is the channel viewed at the top of the top pane, and is selected clicking one of the first buttons on the View toolbar which are labeled "All" for all channels (up to the first four channels), "1=L" for the first channel (also known as the left channel) only, and "2=R" for the second (right) channel only. Clicking the "Any" button drops down a menu which allows you to select arbitrary channels for viewing, and in any specified order so that you may specify the "current channel" by putting its number first in the list.
Cropping, Splicing, and Playlists (cut and paste)
Single segment
at a time cut and paste, i.e., splice, types of operation may be requested using the usual cut
and paste Edit→Paste, Insert... command (shortcut key Ctrl+V). You can quickly
cut out segments (to be deleted or copied), repeat segments, reorder segments using these features.
These activities are very useful for extracting and cleaning up small segments from longer sound
files for use with Web pages.
Simply making a file copy of a segment of a waveform file is supported by a File→Save Selection As command.
More complex multiple-segment splicing tasks may be expedited using "Playlists", which are simply lists of segments from the same or different waveform files. Choosing the Audio→Playlist Operations command (or the Playlist toolbar button) brings up a Playlist Operations dialog box which supports additional forms of splicing.
Fades
Fading in or fading out or clearing segments is effected
using the Fade, Clear, Scale or Fill command (Fade toolbar button). These actions
may be applied equally to all the channels, or to each channel independently. To apply to the
entire file, first select the whole file using the Edit→Select All command (Ctrl+A).
The Fade, ... command also supports other actions such as scaling (multiplying by a gain
factor) and overwriting with noise.
Recording
The Waveform File Editor has built-in support for
direct recording into any of the supported waveform file format files. Clicking on the Record
button, or the menu command Audio→Show Recording Toolbar, brings up the Recording toolbar
shown at the right.
The Tooltips for the controls across the top of this toolbar describe their function. While recording the channel level indicators show the current levels of the signals being recorded. If at any time a level is so high that overflow (saturation) occurs the main view background changes from green to red for the remainder of the recording run. The saturation level is a function of the destination file format. .WAV files containing 8 or 16 bit samples are limited to peak signal values of less than 1.0, while no such limitation occurs with 32 bit floating samples.
Recording parameters such as the number of channels,
and the sampling rate, are initially set to that of the currently open file, but may be changed
by clicking on the Change Waveform Properties button, which brings up a dialog box where
these parameters may be changed.
Labels and Waveform Event Lists
Locations
within a waveform may be saved in a label list. Such may be used as simple
bookmarks to facilitate the quick return to selected locations. Label lists may
be saved as plain text files in the "CSV" format, and hence they can also be
used for data collection for subsequent analysis since this file format may be
imported into spreadsheets and other data-analysis programs. The
Labels menu and the Labels toolbar shown at the right are used to manipulate
label lists. Event entries may include just a label and timestamp, or may
include additional data such as the bounds of a waveform segment, or audio
sample values at that location. Saved label lists have the .mwel file name
extension, for "MITSYN Waveform Event List".
Adding Effects such as Reverberation
The Waveform Editor's Effects menu supports tasks such as adding reverberation or echo, frequency band filtering, delaying some channels with respect to other channels, mixing between channels, panning, smoothing, adding vibrato, etc. See the Effects page for details.
Other Types of Waveform Editing/Transformation
Segments of waveform files selected using the Waveform Editor may also be edited using the MITSYN Numeric Array Editor (Edit→Selection Content using Array Editor). Sample values may be drawn in with the mouse, individual sample values may be easily changed. Also such segments may be saved as "wavetable" files. [details]
See Waveform Editor Usage and Implementation for more details.
Last updated 24-Sep-2009