Apple Logic Express 9 - Manual (Page 1032)

To use the automatic Beat Mapping feature
1 Select the region you want to make the project tempo display to, then click the Beats
from Region button in the Beat Mapping track.
The Set Beats by Guide Region(s) dialog opens.
2 Choose the most appropriate note value in the Note Value pop-up menu.
The Note Value defines the timing resolution that is used to create the map.
3 Choose between the following two algorithms:
• Tolerate missing or additional events: This algorithm only uses tempo-relevant transients
for the beat mapping process (selection is based on the project’s current time signature).
This avoids drastic tempo changes, which are usually undesirable. You should use this
algorithm for audio regions.
Note: When using this algorithm, you will achieve the best results with reasonably tight
percussive material. The algorithm will not work well on recordings of performances
that have been played too far off the bar, or provide inconsistent tempo information.
The same is true for very complex, layered drum tracks or melodic material that doesn’t
provide enough transient information.
• Use exactly all existing events: This algorithm uses every detected transient for the
automatic beat mapping process. You’ll only get usable results when using this algorithm
to analyze (MIDI) regions that provide an event for each tempo-significant transient.
4 Click OK to perform the automatic beat mapping process.
Logic Express scans the region based on your chosen algorithm and performs the beat
mapping process.
1032 Chapter 34 Beat Mapping Regions