Sony action cam georeferencing

Extract Gps information and generate speed subtitles for Sony action cameras (HDR-AZ1, HDR-AS100 and others)

Dependencies

dateutils: http://www.fresse.org/dateutils/
ffmpeg
exiftool
gpsbabel
imagemagick
bash
gnu coreutils

Usage

Copy Folders MP_ROOT and PRIVATE to your computer
cd into directory MP_ROOT/100ANV01 (or similar, it is the folder with the .MP4 files) and copy the script in this directory
Make the script executable (chmod +x georef.sh)
Run the script (./georef.sh)
In Kdenlive you can add the created video (the file ending with overlay) in a video track above the original video file. Then add the effect “chroma key” to the overlay video track, go to properties of that effect, click the right color wheel and pick that blue background from the overlay video. Change variance to 150.

Output

The script will try to match the GPS data files with the corresponding video files according to the start date/times
It converts the files to gpx files with the same name prefix as the corresponding video files
It creates a subtitle file with the velocity
It creates a video file with the same resolution and frame rate as the original, but with blue background and the speed in km/h in white

Problems

If the gps starts later, it will not properly match the video/gpx file
Complexity class: O(n^2)

Use at your own risk, no warranties.

#!/bin/bash

#dependencies:
#dateutils: http://www.fresse.org/dateutils/
#ffmpeg
#exiftool
#gpsbabel
#imagemagick

#offset in seconds
offset=3


#go through all gps nmea .LOG files
log_folder="../../PRIVATE/SONY/GPS/"
for file in $(ls "$log_folder/" |grep -i ".LOG$"); do
	gpx="${file%.*}.gpx"
	gpx11="${gpx%.*}_v11.gpx"
	gpx_s="${gpx%.*}_nospeed.gpx"
	#check if gpx file already exists and if file has more then 1 line
	echo "$log_folder""$file"
	if [ ! -s "$gpx" -a `wc -l < "$log_folder/""$file"` -gt 1 ]
	then
		echo converting "$log_folder/""$file"
		gpsbabel -i nmea -f "$log_folder/""$file" -o gpx,gpxver=1.0 -F "$gpx"
		#clean:
		gpsbabel -i nmea -f "$log_folder/""$file" -o gpx,gpxver=1.1 -F "$gpx11"
		grep -iv 'nan\|<speed>\|<geoidheight>\|<course>\|<fix>' "$gpx11" > "$gpx_s"
		rm "$gpx11"

	fi

	if [ -s "$gpx" ]
	then
		gps_create_date=`awk '/<trkpt/{i++}i==1' $gpx |grep -m1 \<time\> |sed -e 's/<time>//g' -e 's/<\/time>//g'`

		for video_file in $(ls ./ |grep -i ".MP4$" |grep -v "overlay"); do
			if [[ `file $video_file |head -n1` == *"empty"* ]]
			then
			   echo "$video_file is corrupt"
			else
				video_create_date=`exiftool -d %Y-%m-%dT%H:%M:%S%Z -p '$CreateDate' $video_file 2>/dev/null`
				#video_create_date_offset=`dateadd "$video_create_date" "+$offset_video" |xargs date "+%s" --date` 
				#let date_diff=$video_create_date_offset-$gps_create_date
				echo "gps date" $gps_create_date
				echo $video_file
				echo "video date" $video_create_date
				date_diff=`datediff $video_create_date $gps_create_date -f '%S'`
				echo $date_diff
				if [ $date_diff -le 3 ] && [ $date_diff -ge -3 ]
				then
					echo match
					mv "$gpx" "${video_file%.*}.gpx"
					mv "$gpx_s" "${video_file%.*}_nospeed.gpx"

					gps_date_corrected=`dateadd $gps_create_date "$offset"rS -f "%Y%m%d"`
					gps_time_corrected=`dateadd $gps_create_date "$offset"rS -f "%H%M%S"`
					echo $gps_create_date
					echo $gps_date_corrected
					echo $gps_time_corrected

					gpsbabel -i gpx -f "${video_file%.*}.gpx" -o subrip,gps_time=$gps_time_corrected,gps_date=$gps_date_corrected,format='%s km/h' -F "${video_file%.*}".srt

					fps=`exiftool -p '$videoframerate' $video_file`
					image_size=`exiftool -p '$imagesize' $video_file`

					convert -size $image_size canvas:blue blanc.png
					#create empty video with speed rendering
					ffmpeg -loop 1 -i blanc.png -i $video_file -shortest -map 0:0 -map 1:1 -filter:v subtitles="${video_file%.*}.srt":force_style='FontSize=45' -c:a copy -c:v libx264 -qp 0 -preset slow -r $fps "${video_file%.*}_overlay_tmp.mp4"
					
					#remove audio
					ffmpeg -i "${video_file%.*}_overlay_tmp.mp4" -an -c:v copy "${video_file%.*}_overlay.mp4"

					rm blanc.png
					rm "${video_file%.*}_overlay_tmp.mp4"
					break
				else
					echo no match
				fi
			fi	
		done
	else
		echo no gpx file
	fi
done

On Github