[OSM-talk] Interleaving GPS traces with video?

[Laurence Penney]

Thanks a lot. I was hoping, I guess, that there was some standard for simply whacking a GPX file inside an MPEG4 container, and maybe even a viewer for such files... Would be doable to make a system that relies on parallel files, i.e. a GPX of the same name as the video file, and a viewer that would plot a marker on a map as the video progressed. The GPX could be trimmed to match the start and end of the video, thus avoiding any video timing issues.

- L

On 27 Mar 2010, at 19:43, simon at mungewell.org wrote:

>> Does anyone have any experience interleaving GPS traces with video?
>> 
>> Some friends of mine are asking about it in relation to skiing and
>> motor-racing, but one could also imagine it being of use to mappers.
>> Ideally I'd like to look up a "time since start of shot" and find the
>> location. You could also look at such a system as generating ~30
>> geo-referenced photos per second. Are there any video formats that handle
>> this in one file, or standards for having a GPX alongside a video file?
>> 
> 
> There is some mention of video mapping on the wiki:
> http://wiki.openstreetmap.org/wiki/Video_mapping
> 
> along with audio mapping:
> http://wiki.openstreetmap.org/wiki/Audio_mapping
> 
> There was a posting on this list a while ago (1 1/2 years or something)
> where someone had overlayed a 2D barcode containing lat/long onto the
> video frame.
> 
> Personnally I think that it is a real head-ache to try and synchronise the
> data track with audio/video, so would suggest that you try to do it at the
> time that the video is recorded.
> 
> Using an OpenTracker (http://www.argentdata.com/products/otplus.html) you
> could encode the GPS information as audio tones as the camcorder runs.
> Open tracker also collects/reports other telemetry with the same system
> (temp, voltage, counts, etc).
> 
> In post production these could be decoded (with 'multimon') and added as
> an overlay, or even processed into a subtitle file.
> 
> Let us know if you succeed in you challenge,
> Simon
>