ERS and Envisat processing

[johntruckenbrodt]

This implements several changes to enable/improve ERS and Envisat processing..

snap

• auxil.orb_parametrize: improved ERS/ASAR orbit handling (more work necessary to always select the best available file, because all options are limited in time (e.g. use option 1 if possible, fall back to option 2 otherwise, etc.); needs a download functionality like S1.auxil.OSV to know which ones are available)
• util.geocode:
  • explicitly use 'Latest Auxiliary File' for Envisat calibration (just for readability, this is already the default value of the parsed node; other options: 'Product Auxiliary File', 'External Auxiliary File')
  • leave calibration node polarizations field empty when processing all polarizations (otherwise processing may finish without errors but no product is being written; looks like a SNAP bug, also reported in step-44830)
  • Calibration in/out band handling improvements
    • select source bands based on sensor and acquisition mode (also described in step-44830)
    • more explicit handling of output bands: all that are not needed set to False
    • commented out output bands that are apparently not needed
  • fixed sarsim-cc geocoding:
    • old: SAR-Simulation->Cross-Correlation->Terrain-Flattening->SARSim-Terrain-Correction (does not work because Terrain-Flattening does not pass through any source layers)
    • new: SAR-Simulation->Cross-Correlation->Warp->Terrain-Flattening->Terrain-Correction
    • this reveals a flaw in current SNAP processing: the additional Warp step introduces unnecessary resampling, the created lookup table is not passed between operators and thus makes the process inefficient, the whole procedure only works with EPSG:4326 as map geometry thus, by the looks of it, requiring three forward geocoding steps (for SAR-Simulation, Terrain-Flattening and Terrain-Correction, respectively)
• auxil.groupbyWorkers: add Warp operator to the group of its source node, because it cannot be executed alone (just like ThermalNoiseRemoval)
• ancillary layer writing fix: a layover shadow mask can also be created by SAR-Simulation, but the output layer is named differently ('layover_shadow_mask' instead of 'layoverShadowMask' by Terrain-Correction); this must be handled correctly in auxil.writer

drivers

• ESA:
  • scan_Metadata:
    • read out all MPH, SPH, DSD and GEOLOCATION_GRID_ADS metadata and expose it via meta['origin']
    • use absolute orbit number as frameNumber instead of product counter (which often seems to be 0)
    • convert original metadata to Python types (int, float, datetime)
    • renamed several meta attributes
      • incidenceAngleMin -> incidence_nr
      • incidenceAngleMax -> incidence_fr
      • rangeResolution, azimuthResolution -> resolution (tuple)
      • neszNear, neszFar -> nesz (tuple)
  • new method geo_grid (like for SAFE)
  • corrected acquisition_mode for ASAR WSM, WSS
  • added MR product type
• BEAM_DIMAP
  • improved metadata parsing
    • incidenceAngleMidSwath not always present, use incidence_near and incidence_far alternatively
    • the cycle number may be named orbit_cycle or CYCLE
    • for pyroSAR frameNumber, use ABS_ORBIT, not data_take_id as for Sentinel-1
    • added further meta attributes: swath, looks
    • always four Polarizations fields present, some may be set to None -> filtered out
    • for Sentinel-1 the product and acquisition_mode attributes can be obtained from ACQUISITION_MODE and PRODUCT_TYPE respectively; for ASAR/ERS ACQUISITION_MODE is missing and PRODUCT_TYPE contains the original values, e.g. 'ASA_APP_1P' -> must be abstracted
  • added MR product type
• ID
  • added methods start_dt and stop_dt returning timezone-aware datetime objects

ancillary:

• multilook_factors: fixed bug in returning 0 as range factor

[coveralls]

Pull Request Test Coverage Report for Build 18854125071

Details

• 176 of 292 (60.27%) changed or added relevant lines in 5 files are covered.
• 69 unchanged lines in 5 files lost coverage.
• Overall coverage decreased (-0.7%) to 52.935%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pyroSAR/ancillary.py	2	3	66.67%
pyroSAR/snap/auxil.py	34	41	82.93%
pyroSAR/snap/util.py	42	77	54.55%
pyroSAR/drivers.py	96	169	56.8%

Files with Coverage Reduction	New Missed Lines	%
pyroSAR/S1/auxil.py	1	42.31%
pyroSAR/drivers.py	3	65.22%
pyroSAR/snap/util.py	4	52.11%
tests/test_auxdata.py	8	85.48%
pyroSAR/auxdata.py	53	39.75%

Totals
Change from base Build 18345680634:	-0.7%
Covered Lines:	3887
Relevant Lines:	7343

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💛 - Coveralls