The FreeRunner can record audio. It is nice to record audio: for example I can run the recording in background while I keep tangogps in the screen, and take audio notes about where I am while I am doing mapping for OpenStreetMap.
Here is the script that I put together to create geocoded audio notes:
#!/bin/sh WORKDIR=~/rec TMPINFO=`mktemp $WORKDIR/info.XXXXXXXX` # Sync system time and get GPS info echo "Synchronising system time..." getgps --sync-time --info > $TMPINFO # Compute an accurate basename for the files we generate BASENAME=~/rec/rec-$(date +%Y-%m-%d-%H-%M-%S) # Then give a proper name to the file with saved info mv $TMPINFO $BASENAME.info # Proper mixer settings for recording echo "Recording..." alsactl -f /usr/share/openmoko/scenarios/voip-handset.state restore arecord -D hw -f cd -r 8000 -t wav $BASENAME.wav echo "Done"
It works like this:
- It synchronizes the system time from the GPS (if there is a fix) so that the timestamps on the wav files will be as accurate as possible.
- It also gets all sort of information from the GPS and stores them into a file, should you want to inspect it later.
- It records audio until it gets interrupted.
The file name of the files that it generates corresponds to the beginning of the recording. The mtime of the wav file obviously corresponds to the end of the recording. This can be used to later georeference the start and end point of the recording.
You can use this to check mixer levels and that you're actually getting any input:
arecord -D hw -f cd -r 8000 -t wav -V mono /dev/null
You may now want to experiment, in JOSM, with "Preferences / Audio settings / Modified times (time stamps) of audio files".