Hi.

If I have a global positioning satellite receiver GPS on a laptop USB port, and also a video input fed to the computer;

How to stamp latitude, longitude and heading on each video frame recorded in the hard drive as to log images location for a towed submarine camera ?

 

To make it harder; if the camera is towed 100 horizontal metres behind the boat, how to compensate the stamped readings for accuracy at all headings ?

Miguel

If the app is open source this should be really easy. If not you'll want to run a script that automatically adds the location to the images as they're taken. (you're taking pictures or video?)

 

I assume you have some programming experience cause I doubt anyone is going to actually do this for you.

For still images you can use this web site, which correlates the timestamps on a GPS device that logs to GPX format with the timestamp a camera places in the EXIF data on your photos. The site can then plot your movements on a Google Map and insert pinpoints with the photos that show where they're taken:

 

http://walkingboss.com

Hmmm... I would need to be smarter to understand the thingy.

 

The camera is a video camera, not a photographic camera, no time stamp in any EXIF, ant time is irrelevant. The video would be captured as individual pictures every certain amount of time triggered depending on the speed being towed to take pictures 'back to back' or properly said, sequential without overlap nor gaps.

And every frame has to be saved with its Lat/Long/heading as 'subtitles' to the hard drive, no posterior editing/adding/insertion of any GPS logs onto the frames.

 

The "run a script" does it mean running a program? Made with basic, visual basic, C... ? How to 'tap' to the GPS data entering the computer with such program ?

 

Another data to be superimposed as 'subtitles' to each frame is from a depth sensor.

 

I was a programmer too long ago to remember how to do it now.

 

Miguel

The "run a script" does it mean running a program? Made with basic, visual basic, C... ? How to 'tap' to the GPS data entering the computer with such program ?

If the programs you're using are open source this would be extreamly easy. Otherwise you'll have to read the manual or something and hope there's some way to echo the gps data where you can then write a program to edit your video (stream the video to vlc or something and edit it as you get the video, technically you'll probably lag a bit but that's no big deal).

 

I would also recommend what bascule suggested or a similar program if these sorts of things already exist.

Why can't the latitude / longitude information be applied retroactively?

 

Why are you using a video camera to take a series of still photos?

 

By using timestamps, you can correlate the timestamps on the GPS data with the timestamps on your photos, and thus apply the latitude / longitude info retroactively.

 

This can also be published in the form of a GeoRSS PhotoStream

Thanks for the responses

 

 

Why can't the latitude / longitude information be applied retroactively?

 

------> I would say that is not a task for a thousand pictures every day and having to return to port to do hours of editing. It is for search and recovery; not mapping.

 

Why are you using a video camera to take a series of still photos?

 

-------> That is waterproof to 100 m on hand, and gives real time monitoring. A digital camera for still pictures, good to 100 m, with coaxial video cable to monitor in real time at the surface... have not seen one yet.

 

By using timestamps, you can correlate the timestamps on the GPS data with the timestamps on your photos, and thus apply the latitude / longitude info retroactively.

------> Naaaah. The photos would hardly have time stamps a second apart, it would be high speed bottom scanning.

 

This can also be published in the form of a GeoRSS PhotoStream

------> That I do not know what it is. I will search for it.

 

Miguel:-)