Thanks guys,
So you need a program called "dashware" That is what you use to add the gauges to the video. Then the hard bit.. you need to match the GPS track in line with the video. I have found it best to have a moment on the GPS and Camera where you do something crazy out of the ordinary to make a point to match from. Leave the camera rolling as stop and start makes it impossible.
Once matched check the next time you stop and start in the video that the speedo drops to 0 and takes off at the right time...
Another one of a Jibe at Port Sorell...
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