Apple Logic Pro 9 - Manual (Page 1045)

Tip: If using the “Tolerate missing or additional events” algorithm, assign the respective
transient manually before using the Beats from Region function, as this will ensure that
a certain beat is always part of the beat mapping process. The resulting map will always
contain this manually mapped position. If Logic Pro is not able to find a consistent tempo,
you should try the following: Manually map (up to) two significant beats and click the
Beats from Region button again. The two manual mapping points define a resulting
tempo that will be used as the basis for automatic beat mapping. If this method fails,
record a MIDI region which contains synchronized regular notes, and use this as a guide
region.
To beat map audio material that contains tempo changes
1 Cut the audio material at the precise position of any tempo changes.
2 Lock the SMPTE position of each audio region.
3 Select the first region and perform the automatic beat mapping process as already
described.
4 Continue with all following audio regions.
Beat Mapping to Scene Markers
If the global Video track is visible, a QuickTime movie is loaded, and the Detect Cuts
function (in the Video track) is used, the detected scene markers appear as available
mapping positions (vertical lines) at the bottom of the Beat Mapping track. You can easily
define a scene cut position as the first downbeat of a bar—by allocating it to the bar
position, as described above.
Beat Mapping to Markers
If the Marker track is visible, you can use the desired marker as a mapping position (vertical
line at the bottom of the Beat Mapping track) by clicking it. Shift-click to assign multiple
markers as beat mapping positions. Once done, you can hide the Marker track.
1045 Chapter 34 Beat Mapping Regions