Dictacam

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One of the best methods of recording street names and points of interest is to use a digital camera. However, it has some limitations. It is not at all easy to take photographs single handed from a moving bicycle or car. Nor is it easy to do this when it is dark. Another popular method is to use a dictaphone, but this has the drawback that there is no easy way to accurately correlate the voice recording with a point on the track logs. The solution? Dictacam!

Some digital cameras have a mode that allows a voice tag to be recorded along with each photograph. Typically this is a 5 second recording. So while travelling on you bike or in your car you can press the shutter button, but with the camera aimed at nothing in particular, and then say out loud the name of the street. You get an accurate waypoint at the exact time the photograph was taken, and you get a corresponding voice recording containing the name of the feature.

You can subsequently locate the photographs on the track log using JOSM's .jpg image import capability, and you can play the sound track by opening the corresponding .mpg audio recording.

The following instructions are based on using a Sony Cybershot DSC-P10. I don't have experience with other cameras, they may or may not have some or all of the neccessary features and they might well use different terminology anyway. YMMV.

Camera Setup

For best results there are a number of settings that can help to produce better results:

  • Set the camera mode to Voice. In this mode it will take a photograph and then record a 5 second voice tag. If your camera doesn't have this capability then you won't be able to configure it as a dictacam - so stop here.
  • Switch off auto-focus. If your camera has the ability to do so, turn off auto-focus and set it to infinity or something. You aren't interested in the photo so it doesn't matter, but a fixed focus gives a much faster shutter response than auto-focus, especially in the dark when it is hard for the camera to find anything to focus on.
  • Switch on shutter sound effects. If you camera can be configured to make a sound when the photo is taken then enable this. It provides feedback to help you know that the photo has been taken, without having to look at the camera. There may also be a setting to give an audible bleep at the end of the 5 second voice recording. If there is then that also helps.
  • Select lowest image size. Set the picture resolution to the lowest possible setting (1.2 mega pixels or whatever). You don't need the photograph and doing this will save space on your memory card and reduce battery usage. This means that you can stay out mapping for longer :-)
  • Switch off the flash. You definitely won't need this!

Post-Processing

When you upload you camera's files you should find that for each photograph there are two files. One will be the photograph itself in a .jpg file. The other will be an .mpg file which should contain the 5 second audio-track.

  • Open and have ready the folder containing the corresponding .mpg files. This can be arranged so that it is visible to one side of JOSM if you like.
  • Use JOSM to import the .jpg images and sync them with your tracklog.
  • Click on each image in JOSM to see it's file name.
  • Double click on the corresponding .mpg file to play the audio track.

Camera Specific Notes

If you find that this technique works with your camera please add any camera specific notes here.

  • Sony Cybershot DSC-P10 This is quite an old model, but works well as a dictacam.