Some noise sources form very characteristic noise patterns, which can be easily localized by using pattern recognition techniques. Thumps and some kinds of scratches are good examples of disturbances, which can be easily identified by shape.
To search for typical noise patterns:
1. Mark a fragment of the signal, which will serve as a reference pattern. The reference block should be at least 50 and at most 500 samples long.
2. Select the Find pattern command from the Toolbox menu and press the Get button. The selected fragment of the signal will be displayed at the top of the dialog.
3. Specify the requested degree of similarity between the reference pattern and its preferences by selecting the three accuracy factors (shape, scale and length).
4. Press the FORWARD
/BACKWARD
button to initialize search in a chosen direction. If the search is successful, the corresponding portion of the recording will be highlighted and the cursor will be placed at its beginning. If a pattern matching the reference with a prescribed degree of accuracy cannot be found in a given direction, an appropriate message appears on the screen.
5. When finished, press the Close button to close the Find pattern dialog.
DART XP Pro allows you to save up to 16 typical noise patterns. To add a new pattern to an archive, press the Add button. To remove it from an archive or to change its name use the Remove and Rename buttons, respectively.
At any time you can reduce the size of the Find pattern dialog by pressing the MINIMIZE
button situated in its upper right corner. The reduced size dialog contains the search forward/backward and close buttons only. Use the MAXIMIZE
button to switch back to the full size dialog.
A reference pattern is always taken from the currently displayed channel of a stereo recording. If both channels are displayed DART XP Pro will ask you which one to choose. The search criteria are straightforward - only the displayed channels are browsed when the system looks for the matching patterns. This means that if you would like to inspect both channels of a stereo recording, both should be shown on the screen.