photoprism/internal/meta/gps.go
2021-02-05 09:45:28 +01:00

81 lines
1.7 KiB
Go

package meta
import (
"regexp"
"strconv"
"github.com/dsoprea/go-exif/v3"
)
// var GpsCoordsRegexp = regexp.MustCompile("(-?\\d+(\\.\\d+)?),\\s*(-?\\d+(\\.\\d+)?)")
var GpsCoordsRegexp = regexp.MustCompile("[0-9\\.]+")
var GpsRefRegexp = regexp.MustCompile("[NSEW]+")
// GpsToLatLng returns the GPS latitude and longitude as float point number.
func GpsToLatLng(s string) (lat, lng float32) {
if s == "" {
return 0, 0
}
co := GpsCoordsRegexp.FindAllString(s, -1)
re := GpsRefRegexp.FindAllString(s, -1)
if len(co) != 6 || len(re) != 2 {
return 0, 0
}
latDeg := exif.GpsDegrees{
Orientation: re[0][0],
Degrees: GpsCoord(co[0]),
Minutes: GpsCoord(co[1]),
Seconds: GpsCoord(co[2]),
}
lngDeg := exif.GpsDegrees{
Orientation: re[1][0],
Degrees: GpsCoord(co[3]),
Minutes: GpsCoord(co[4]),
Seconds: GpsCoord(co[5]),
}
return float32(latDeg.Decimal()), float32(lngDeg.Decimal())
}
// GpsToDecimal returns the GPS latitude or longitude as decimal float point number.
func GpsToDecimal(s string) float32 {
if s == "" {
return 0
}
co := GpsCoordsRegexp.FindAllString(s, -1)
re := GpsRefRegexp.FindAllString(s, -1)
if len(co) != 3 || len(re) != 1 {
return 0
}
latDeg := exif.GpsDegrees{
Orientation: re[0][0],
Degrees: GpsCoord(co[0]),
Minutes: GpsCoord(co[1]),
Seconds: GpsCoord(co[2]),
}
return float32(latDeg.Decimal())
}
// GpsToLng returns a single GPS coordinate value as floating point number (degree, minute or second).
func GpsCoord(s string) float64 {
if s == "" {
return 0
}
result, err := strconv.ParseFloat(s, 64)
if err != nil {
log.Debugf("metadata: failed parsing GPS coordinate '%s'", s)
return 0
}
return result
}