David<br>This sounds like it will be super cool (sorry about the pun). I'll be trying this out on my next expedition.<br><br>Etienne<br><br><div class="gmail_quote">On Wed, Feb 20, 2008 at 6:16 PM, David Earl <<a href="mailto:david@frankieandshadow.com">david@frankieandshadow.com</a>> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">To augment continuous audio synchronized with waypoints that I mailed<br>
about earlier this week, I have now also added the facility to work with<br>
continuous audio recordings on tracks where you don't have or don't want<br>
to use explicit GPS waypoints. This will be in tomorrow's JOSM build.<br>
<br>
After loading your GPX track, right click on the GPX layer and choose<br>
the new "Make Sampled Audio Layer" option. This will ask for your WAV<br>
file; then it will create a new layer combining the audio track with the<br>
GPX trackpoints to produce a set of audio markers laid out along the<br>
track. These will be at least 15 seconds and 75 metres apart, or<br>
whatever values you choose for these in Advanced Preferences settings<br>
for "marker.audiosampleminsecs" and "marker.audiosampleminmetres"<br>
respectively)(*).<br>
<br>
You're then in a similar position to applying audio to explicit<br>
waypoints as per my previous changes: you can synchronise to a marker<br>
near the beginning of the track, play by reference to the visual<br>
position on the map, jump forward and back in the commentary, pause and<br>
resume and so on.<br>
<br>
The sampled markers are named according to the time offset from the<br>
beginning of the sound track (e.g. "1:37", "1:09:07"). To facilitate<br>
this, I've reversed the default for whether to show text for button<br>
markers (audio, image and web), but you can turn these off as before,<br>
transiently from the right button layer menu, or permanently by setting<br>
marker.buttonlabels to false in Advanced Preferences.<br>
<br>
David<br>
<br>
<br>
(*) the defaults are chosen so that they are about the same for a<br>
cyclist travelling at 5 metres per second (about 11mph or 18km/h), so<br>
you get a useful but not overwhelming number of samples, but if you stop<br>
or slow down, you don't suddenly get a concentration of points close<br>
together. Of course if you stop and then record intermittently, you'll<br>
still find it hard to locate the bit of commentary you want - the whole<br>
idea is it is related to landmark junctions or loops you make in the<br>
road or whatever. If you're in a car you might want to set the sample<br>
time a bit shorter, say 7.5 in an urban environment, though the distance<br>
would probably be the same unless you actually want a higher or lower<br>
density, and maybe 60 to 90 seconds apart if walking at a typical 1 m/s.<br>
<br>
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</blockquote></div><br>