undef

s1a-ew-grd-vv-20160826t211705-20160826t211809-012777-01420d-001_filter

s1a-ew-grd-vh-20160826t211705-20160826t211809-012777-01420d-002_filter

s1a-ew-grd-vv-20160826t211705-20160826t211809-012777-01420d-001_winddir

s1a-ew-grd-vh-20160826t211705-20160826t211809-012777-01420d-002_winddir