Release 5.2 (R5.2)

• Added option to provide product static-layers data access for each individual burst product using the substrings "{burst_id}" and "{end_date}";
• Fixed writing of cloud-optimized GeoTIFF (COG) files for GDAL >= 3.8;
• Updated S1-reader version to v0.2.4;
• Added RTC-S1 product metadata field informing the average zero-Doppler spacing in meters: averageZeroDopplerSpacingInMeters (HDF5 header) and SOURCE_DATA_AVERAGE_ZERO_DOPPLER_SPACING_IN_METERS (GeoTIFF files).
• Raise an error if the bounding polygon parsed from the S1 annotation files is invalid or empty;
• In the parallel processing mode through the script rtc_s1.py, if at least one child process fails, remove all processed files, and raise an error.

Release 5.1 (R5.1)

• GeoTIFF metadata values are not capitalized.
• Update the default browse image number of lines (height) from 1024 to 2048.
• Update the metadata field corresponding to the bbox pixel coordinate convention from "Upper left corner (ULC)" to "Edges/corners. Xmin, Ymin, Xmax, Ymax.".
• Update the metadata field associated with the backscatter to dB conversion from "BACKSCATTER_DB = 10*LOG10(BACKSCATTER_LINEAR)" to "10*LOG10(BACKSCATTER_LINEAR)".

Release 5 (R5)

• Fixed default burst file names to follow the RTC-S1 and RTC-S1-STATIC products file naming convention.
• Removed the runconfig flag apply_correction_luts and enabled existing flags. apply_bistatic_delay_correction and apply_dry_tropospheric_delay_correction that were previously being ignored in the processing.
• Renamed the metadata field beam ID to sub-swath ID.
• Remove config files from the products' metadata.
• Added the OPERA SDS contact information.
• Added static layer data access field to the RTC-S1 metadata.
• Added option, disabled by default, to create browse images from dual-pol datasets using the color composition: red: co-pol, green: cross-pol, blue: co-pol divided by cross-pol.
• The product version can now be a number of a string (e.g., "1.0.0-beta" or "1.0.0”).
• Removed diagnosticModeFlag from the HDF5 metadata.
• HDF5 metadata field productSpecificationVersion is now a string and burstGeogridSnapX, burstGeogridSnapY, rangeBandwidth, and maxNoiseEquivalentSigmaZero are now float numbers.
• Updated the name of geocoding and RTC algorithms.
• Substituted underbars with dashes in product type.
• Removed az/rg resolution in meters from RTC-S1-STATIC metadata.
• Converted the metadata HDF5 dataset ceosAnalysisReadyDataPixelCoordinateConvention as an attribute of the HDF5 dataset boundingBox.

Cal/Val Point Release 4 (R4.1)

• Created a separate workflow for RTC-S1-STATIC products.
• product_type now accepts two values: “RTC_S1” (existing) “RTC_S1_STATIC” (new value to indicate that the output product is a static layer RTC-S1-STATIC product).
• Updated file names of the output layers to follow RTC-S1 and RTC-S1-STATIC file naming convention.
• Added a new static layer: "rtc_anf_gamma0_to_sigma0” to enable users to normalize RTC-S1 backscatter from gamma0 to sigma0.
• The parameter save_layover_shadow_mask was renamed to save_mask.
• The file {product_id}_layover_shadow_mask.tif was renamed to {product_id}_mask.tif.
• Added browse images for RTC-S1-STATIC products.
• Updated GeoTIFF and HDF5 metadata (improve compliance with CEOS ARD specifications).
• Improved the radiometric terrain correction algorithm.
• Improved algorithm for creating the layover/shadow mask (now saved as "mask").
• Added selection of the RTC area_beta_mode. Options are: "auto", "pixel_area", "projection_angle".
• The parameters save_rtc_anf_psi was renamed to save_rtc_anf_projection_angle.
• Refactored code and fixed bugs.

Cal/Val Release 4 (R4)

• Add dry troposphere and bistatic delay corrections;
• Add coverage check for ancillary inputs (DEM);
• Provide multiple updates to the OPERA RTC-S1 product metadata:
  • Remove /science/SENTINEL1 and /science/SENTINEL1/RTC base paths from RTC-S1 HDF5 metadata;
  • Rename HDF5 imagery group grids to data;
  • Add RFI fields.
  • Add layer name and description to GeoTIFF metadata;
  • Update metadata field orbitType.
• GeoTIFF files
  • Update default compression algorithm from ZSTD to DEFLATE;
  • Remove NBITS=16 from default runconfig
• Mosaicking
  • Update functions to compute burst and mosaic geogrids
  • Separate runconfig burst and mosaic geogrids
  • Add mosaicking with different output formats;
  • Add support to mosaicking with negative offsets;
  • Add handling of Byte and Integer images;
  • Save color table and no data values into the output mosaic (when available).
  • Provide three mosaicking options: average, first, and bursts_center
  • Reproject burst product before mosaicking if needed
• Layover/shadow mask
  • Add fill value and color table to the layover shadow mask;
  • Add option to dilate the layover/shadow mask;
• Add option to skip process if output geocoded files exist;
• Other minor updates:
• Minor updates:
  • Substitute metadata field ISCEVersion to isce3Version;
  • Update some comments, fix typos, indentation, and bugs;
  • Update dem_description to dem_file_description;
  • Separate runconfig burst and mosaic geogrids;
  • Remove requirement of save_nlooks = True;
  • Add test runconfig at tests/runconfigs/s1b_los_angeles.yaml and use it for workflow testing rather than using the runconfig downloaded from zenodo (during workflow test).

Gamma Release (R3)

Updates since last release (Beta Point Release v0.2):

• Add a parallelized version of the workflow as app/rtc_s1.py. The single-job workflow was moved to app/rtc_s1_single_job.py;
• Add option (enabled by default) to create browse images;
• Add GeoTIFF metadata to the GeoTIFF output files (e.g., RTC-S1 imagery and secondary layers);
• Add workflow test;
• Use mode "AVERAGE" when creating RTC-imagery COG overlays;
• Allow the product ID to have a template substring “_{burst_id}” that is substituted by the burst ID of the RTC-S1 product;
• Refactor code, fix bugs, and update docstrings/comments.

Beta Release Point Release 2.1 (R2.1)

Point release to remove checks that ensure that the mosaic and bursts products have the same EPSG code and pixel spacing

Beta Release

Changes Since v0.1:

• RTC-S1 polarimetric imagery is saved as individual single-band cloud-optimized GeoTIFFs (COGs);
• Option to use a burst database file to generate RTC-S1 products with constant geographic grids;
• Added option to generate the layover/shadow mask layer;
• The base HDF5 dataset group was changed from CSAR to SENTINEL1;
• Only one secondary layer is produced by default: layoverShadowMask;
• Output file names have been updated to match the RTC-S1 file naming convention (see product specs);
• Runconfig product_path_group was renamed to product_group;
• HDF5 default extension was changed from ‘.nc’ to ‘.h5’;
• Option to create COG files with different compression algorithms and different number of bits (other than 32). Default compression is ZSTD, and default NBITS is 16;
• Added processing_type and product_version options to the runconfig;
• Added placeholder parameters for apply_bistatic_delay_correction and apply_dry_tropospheric_delay_correction in the runconfig;
• Updated runconfig default values (rtc_min_value_db was set to -40 and RTC dem_upsampling to 2).

Interface (IF) Release

The interface (IF) release represents the initial release of the Science Algorithm Software (SAS) for generating the OPERA (Observational Products for End-users from Remote-sensing Analysis) Level 2 (L2) Radiometric Terrain-Corrected (RTC) product from Sentinel-1 A/B (RTC-S1). The primary executable of the SAS is the Python script app/rtc_s1.py. It requires a run configuration file (runconfig file) that defines the parameters for executing the SAS.