Does somebody know where you can find the relative orbit number of a Sentinel 1 image? I know it should be somewhere in the metadata (the xml-file), but I can't find it.
3 Answers
You actually can find the relative orbit number of sentinel-1 image from the filename by deriving absolute orbit number provided in the name.
Sentinel-1A Relative Orbit Number = mod (Absolute Orbit Number orbit - 73, 175) + 1
Sentinel-1B Relative Orbit Number = mod (Absolute Orbit Number orbit - 27, 175) + 1
Yes you are right. You need to parse the manifest.xml
file.
Here's how to do it in Python:
import xml.etree.ElementTree as ET
tree = ET.parse(manifest_path)
ns = {'safe': 'http://www.esa.int/safe/sentinel-1.0'}
start_relative_orbit_number = tree.find('.//safe:relativeOrbitNumber[@type="start"]', ns).text
end_relative_orbit_number = tree.find('.//safe:relativeOrbitNumber[@type="stop"]', ns).text
Here is your information right here.... https://ec.europa.eu/research/participants/portal/doc/call/fp7/fp7-space-2012-1/31660-s1-rs-mda-52-7441_v2_2_productspecification_en.pdf
More information there if you have not seen this :
https://sentinels.copernicus.eu/web/sentinel/user-guides/sentinel-1-sar/revisit-and-coverage