Audio Trace

Audio Trace - oscilloscope style sound trace.

Index

• About
  • Description
  • Help
    • Color Options
    • Trace Options
    • Volume Options
• Licence
• Version History
• Security

About

Description

Audio Trace renders an oscilloscope or lissajous style trace of sound signals.

A variety of scroll, zoom and fade effects, using pre-defined (or custom) color schemes, can be applied to the trace for visual interest.

Help

Color Options

The Trace|Colors menu item, provides a way to change the color scheme for the trace. The color schemes include 5 colors. One for the background, and two pairs of two colors, for the left/right innner/outer colors.

Select one of the pre-existing color schemes from the drop-down, or tweak the colors of a scheme by clicking the appropriate color button.

Trace Options

The Trace|Options menu item, provides access to the main configuration for the trace.

Each option has tooltip help (when you point the mouse at it), so here we will just explain some of the terms.

Trace Style. Provides a choice between the standard 'height v. time' oscilloscope style plot and a lissajous ('height v. gradient/rate of change) plot. The slider to the right of the checkbox allows the visual gain of the gradient to be amplified.

Visual Gain. Some sounds have a very low sound throughput (not very loud), this slider can be used to increase the (visual) size of the signal.

Sample Size. This determines the length of the 'chunk' in time that is displayed on each rendering. Short samples are better at displaying higher frequencies, while long time samples are better for showing the overall 'shape' of a sound (similar to the ADSR envelope of musical instrument sounds) or the rhythm and beat of music.

Line Size. Sets the thickness of the line used to draw the left/right traces. The thicker the line is, the more of the 'back' trace will be covered by the front trace. Thin lines appear very sharp and angular at turning points, and become more rounded and smooth as the line thickness rises.

Fade Rate. What happens to old traces, is where this program becomes very pretty. Keep a low 'Fade Rate' setting to retain earlier traces longer. Then a 'Scroll Step' or 'Zoom Step' can be alloted to cause the older traces to gradually 'slide' or 'expand' off the screen, or 'fall' back to the middle.

Scroll Rate. A 'Scroll Step' can be alloted to cause the older traces to gradually 'slide' off the screen, or 'fall' back to the middle.

Zoom Rate. A 'Zoom Step' can be set to cause the older traces to gradually 'expand' off the screen, or 'contract' back to the middle.

Volume Options

Show Volume. The Trace|Volume|Show Volume checkbox menu item configures whether to display volume bars for the audio signal. When showing, it displays the RMS volume for the last sampled chunk in semi-transparent volume meters in the lower left/right of the plot. If the signal strength drops low, the background color turns yellow to mean a weak or soft signal - while even lower, it turns red to indicate 'no signal detected'.

Match Trace Colors. The Trace|Volume|Match Trace Colors checkbox menu item allows the volume level colors to match those of the trace they are displaying. Normally the colors run from green for low volume, through red for high volume.

Low Volume Boost. The Trace|Volume|Low Volume Boost checkbox menu item increases the apparent size of the volume for low signal levels. The RMS volume is returned as a value between 0 (no signal) and 1 (maximum possible loudness). When enabled, the low volume boost option displays the square root of that RMS value, increasing the apparent size of low volume signals, at the expense of compressing the range of volumes for loud signals.

Licence

The Audio Trace software is offered to the general public under a Freeware licence.

Version History

Audio Trace is versioned by the date it was uploaded, in format YY.MM.DD, the latest version is 10.01.31. This date is also added into the program and shown when the About menu item is selected. Versions prior to 09.08.11 are listed as a simpler version number e.g. 0.2 or 1.0.

• Audio Trace version 10.01.31
  • Corrected colors. The 'color matched volume bars' introduced in v. 09.07.11 made it clear there was confusion between left and right channels. The left and right shown on the screen, did not match the left/right colors in the TraceColorOptionsPanel, they were reversed. After some careful observation of the volume bars using tracks that had very distinct stereo effects, it was determined the volume bars were correct, so the color panel was changed to match them.
• Audio Trace version 09.08.11. Significant update in conjunction with the release of Tracker music player which is mentioned on the Tracker sound tool thread on the Sun - Java Sound forum.
  • Changed volume bars to allow them to be configured to match the colors used for the left and right traces.
  • Adapted the Audio Trace to be Configurable, and use Parameters for its initial configuration.
  • Factored out the menus and color and trace options panels into a separate package. This allows a much smaller download for apps. that do not intend to offer a JMenuBar, or otherwise no way for the user to alter the trace options or colors.
  • A number of improvements in the audio stream parsing and interpretation
    • Corrected errors in parsing some sound formats, included support for new formats
    • Implemented RMS volume calculation (whereas previously it was simply reporting the 'average of the absolute value')
• Audio Trace version 1.0 - First release to the general public, as part of Audio Trace, which itself might re-appear 'real soon now'.
• Audio Trace version 0.2 - Bytecode manipulation refined.
• Audio Trace version 0.1 - First release (source to usenet).

Security

Audio Trace can do everything it does, when deployed in a security sandox.