DroneMapper.com: GPX File Generation from UAV Flight Controller Logs

DroneMapper_buildgpx.php

#!/usr/bin/php
<?php
/*
 * Change date_default_timezone_set to your flight timezone, you will also
 * need to add a -geosync offset for exiftool on the command line if the 
 * time (hour) field doesn't match.
 */
date_default_timezone_set('Europe/Berlin');

/*
 * Input/Output files
 */
$incomingfile = "./MAVinci.csvm";
$outputfile = "./MAVinci.gpx";

function getGps($exifCoord, $hemi) {
    $degrees = count($exifCoord) > 0 ? gps2Num($exifCoord[0]) : 0;
    $minutes = count($exifCoord) > 1 ? gps2Num($exifCoord[1]) : 0;
    $seconds = count($exifCoord) > 2 ? gps2Num($exifCoord[2]) : 0;
    $flip = ($hemi == 'W' or $hemi == 'S') ? -1 : 1;
    return $flip * ($degrees + $minutes / 60 + $seconds / 3600);
}

function gps2Num($coordPart) {
    $parts = explode('/', $coordPart);
    if (count($parts) <= 0)
        return 0;
    if (count($parts) == 1)
        return $parts[0];
    return floatval($parts[0]) / floatval($parts[1]);
}

/*
 * Build GPX
 */
  $mygpx = '';
  $mygpx .= '<?xml version="1.0"?>';
  $mygpx .= "\n";
  $mygpx .= '<gpx creator="http://dronemapper.com" version="1.0" xmlns="http://www.topografix.com/GPX/1/0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.topografix.com/GPX/1/0 http://www.topografix.com/GPX/1/0/gpx.xsd">';
  $mygpx .= "\n";
  $mygpx .= '<trk>';
  $mygpx .= "\n";
  $mygpx .= "\t".'<number>1</number>';
  $mygpx .= "\n";
  $mygpx .= "\t".'<name>DroneMapper UAV</name>';
  $mygpx .= "\n";
  $mygpx .= "\t\t<trkseg>\n";

  $row = '';
    if (($handle = fopen($incomingfile, "r")) !== FALSE) {
      /*
       * Use fgetcsv with field delimited of " "
       * You can change this to "," or "\t" for different formats.
       */
      while (($data = fgetcsv($handle, 1000, " ")) !== FALSE) {
      $num = count($data);
      $row++;

        /* Skip headers */
        if(!preg_match("/JPG/i", $data[2])) {
          continue;
        }

          /*
           * You can change the $data[X] to obtain different log fields.
           * This is useful if you are processing a UAV log from a different
           * company or you generate your own.
           */
          print "\tGPS Timestamp: " . $data[3] . "\n";
          print "\tGPS Lat: " . $data[5] . "\n";
          print "\tGPS Lon: " . $data[4] . "\n";
          print "\tGPS Altitude: " . $data[13] . "\n";

          $mygpx .= "\t\t\t<trkpt lat=\"".$data[5]."\" lon=\"".$data[4]."\">\n";
          $mygpx .= "\t\t\t\t";
          $mygpx .= '<ele>'.$data[13].'</ele>'."\n";
          $mygpx .= "\t\t\t\t";
          $mygpx .= '<time>'.date("Y-m-d\TH:i:s\Z", $data[22]).'</time>'."\n";
          $mygpx .= "\t\t\t";
          $mygpx .= '</trkpt>'."\n";
      }
    fclose($handle);
    }

$mygpx .= "\n\t\t";
$mygpx .= '</trkseg>';
$mygpx .= "\n\t";
$mygpx .= '</trk>';
$mygpx .= "\n";
$mygpx .= '</gpx>';

/* Write GPX */
file_put_contents($outputfile, $mygpx);
?>