History

0.25.0

  • BEHAVIORAL CHANGE: Add sub-pixel bilinear point rendering for stars and targets, enabled by default. Rendered images differ slightly from v0.24.0; set sim.point_rendering to floor for legacy rendering.

  • Add detector-space ePSF lookup-table renderer. Set sim.mode to epsf and configure sim.epsf.*.

  • Add native ePSF trailed star rendering for star_render_mode: streak to speed dense rate-track star fields.

  • Add tiered ePSF crop rendering for dim stars, defaulting to auto thresholds.

  • Add ePSF transform renderer performance options: budget-scaled scatter batches, point_rendering: phase_nearest, and detector-pixel auto temporal sampling with bin-centered exposure samples.

  • Add block-sum downsampling and normalization options for radial image models and PSF generation.

0.24.0

  • Add sky background models for artificial skyglow, moonlight, twilight, and daytime. Configure background.*.

  • Add modular cloud layers with presets, optical depth, glow, source brightening, and wind motion. Configure clouds.

  • Add deformable radial image models. Use deformable_radial_poly2d and deformable_radial_falloff2d.

  • Add apparent RA/Dec FITS WCS metadata with GAPPT headers.

0.23.1

  • Change radar range rate to instantaneous measurement. See radar.monostatic.range_rate.

0.23.0

  • Add FITS compression support. Set sim.fits_compression.

  • Add seed support for deterministic sampling in random functions. Use seed on $sample.

  • Add simplex gradient noise and lognormal_mu_sigma random. Use $sample: random.simplex or random.lognormal_mu_sigma, with optional center.

  • Add GCVS5 star variability catalog support. Configure geometry.stars.gcvs5.*.

  • Add RA/Dec tracking support. Set geometry.site.track.mode to radec.

  • Add compound operator normalization/evaluation and schema updates. Use $compound with $operator.

  • Enhance radial_cos2d with falloff parameters. Set falloff_height, falloff_width, or falloff_xy.

  • Implement PSF none mode to bypass convolution. Set fpa.psf.mode: none.

  • Refactor FITS header generation to incorporate focal plane roll and fix CD/CRPIX.

  • Add support for additional noise term in FPA and evaluation tests. Configure fpa.noise.misc.

0.22.2

  • Rename tracking pointing toggle from light_transit_correction to track_apparent in config and APIs.

  • Add graceful fallback to geometric LOS when apparent LOS computation fails.

0.22.1

  • Add light transit correction toggle for pointing. Set light_transit_correction in track. Default is true.

0.22.0

  • Add analytical RADAR observations.

  • Batched SGP4 propagation with FOV pre-filtering to speed large catalogs.

  • Add profiling for image generation pipeline and object timing logs. Controlled by enable_profiler.

0.21.2

  • Fix stellar aberration being applied to target incorrectly.

0.21.1

  • Add field of view pre-filter to cull objects for performance. Controlled by enable_fov_filter and optional fov_filter_radius (degrees).

0.21.0

  • Add space-based observer.

0.20.4

  • Update analytical observation for specified observation frames. analytical_obs_frame can be barycentric, geocentric, or observer.

0.20.3

  • Fix star stellar aberration.

  • Add simulation configuration options for deflection, light transit, and stellar aberration.

0.20.2

  • Refactor keras_tensor import logic to support multiple TensorFlow/Keras versions.

  • Refactor great circle into separate module.

  • Reorganize CLI tests to run first to prevent TensorFlow configuration errors.

0.20.1

  • Refactor two-body propagation to remove poliastro dependency.

  • Add object identification fields to analytical observations.

0.20.0

  • Add analytical observations with noise modeling capability.

  • Fix electronic noise casting issue in add_read_noise function.

0.19.4

  • Fix observer altitude units.

  • Fix apparent position of stars to include stellar aberration.

0.19.3

  • Add object ID to FITS and annotations.

0.19.2

  • Add rate-sidereal track mode. This mode takes n - 1 rate track frames and the last frame in sidereal tracking mode.

0.19.1

  • Add TRKMODE to fits header.

0.19.0

  • Add lambertian sphere brightness model for objects. Set object key model mode to lambertian_sphere and set albedo and size (meters) parameters. For 2D simulations, distance (km) and phase_angle (degrees) parameters must also be specified.

0.18.0

  • Add turbulent atmosphere to POPPY PSF generation. Set with psf option turbulent_atmosphere and sim option psf_sample_frequency.

  • Add star and object segmentation annotation. Set sim option save_segmentation to true and star_annotation_threshold to limit stars annotated.

0.17.1

  • Copy useful TensorFlow Addon (TFA) functions into tfa as the TFA project is no longer maintained.

  • Copy tests.

0.17.0

  • Add JSON schema definitions. See schema/v1/Document.json for root schema file.

  • Add observation object type.

  • Add support for cropped sensors.

  • Add altitude to site object. Set site alt parameter in km. Default is 0.

0.16.0

  • Add option to annotate stars. Set sim option star_annotation_threshold to the minimum star brightness magnitude or false to disable. Disabled by default.

  • Add option to show annotated stars in annotated images. Set sim option show_star_boxes to true to enable.

0.15.1

  • Remove clipping of negative values in ground truth files by default.

  • Fix missing dependencies for ground truth file generation.

0.15.0

  • Add support to save ground truth image data to the Annotations directory. Set sim option save_ground_truth to true.

  • Add support for running on CPU with no GPU acceleration.

  • Add CZML options for sensor visualization and object billboard image.

0.14.0

  • Add vector math library.

  • Add CZML output for sensor visualization.

  • Fix objects not updating properly when image renderer is off.

0.13.1

  • Add argument to set folder name in gen_multi.

  • Add environment variable, SATSIM_SKYFIELD_LOAD_DIR, to specify location of Skyfield ephemeris files.

  • Fix incorrect CZML output when image renderer is off.

0.13.0

  • Add ephemeris objects that are propagated with the Lagrange interpolator.

  • Add Cesium CZML output. Set sim option save_czml to false to disable.

  • Add CSV text file star catalog loader. This feature is useful for small catalogs such as Hipparcos and simulating wide FOV sensors.

  • Add multiplier and clipping for radial cosine.

  • Add option to skip image rendering. Set sim option mode to none to bypass image rendering.

  • Update interfaces for newest version of Skyfield, Poliastro, POPPY, and AstroPy.

  • Fix star renderer issue removing stars in field of view for non-square arrays.

0.12.0

  • Add augmentation of SatNet tf.data.Dataset. This feature allows injecting synthetic targets into real data during training.

  • Add FFT convolution to add_patch sprite render and scatter_shift image augmenter for speed improvement.

  • Add cache last PSF FFT to fftconv2p for speed improvement for static PSFs.

  • Add two-body state vector as a trackable target.

  • Add moon and sun model and misc methods to calculate phase angle and target brightness.

0.11.0

  • Add support to render star motion with FFT. Set sim option star_render_mode to fft.

  • Add option to sample photon noise multiple times. Set sim option num_shot_noise_samples to integer number.

  • Add support to render a satellite as a sprite. Set model option in obs.

  • Add support to load and augment sprite model with $pipeline operator.

  • Add cropped POPPY PSF generation.

  • Fix GreatCircle propagator tracking offset.

  • Fix runtime exception when site and track_mode are not defined.

  • Add TensorFlow 2.6 and update TensorFlow 2.2 and 2.4 Docker build file.

0.10.0

  • Add support for piecewise rendering. Set sim option render_size to enable. For example, [256, 256].

  • Add fixed tracking mode with mount azimuth and elevation.

  • Add great circle propagator for targets.

  • Add in-memory image generation. See generator function image_generator.

  • Fix missing stars when FOV crosses zero degree RA.

  • Add curved targets using bezier curve raster. Enabled by default. Set sim option num_target_samples to 2 to enable linear raster.

  • Add LRU cache to star catalog reader.

  • Add option to turn off SNR calculation. Set sim option calculate_snr to false will render targets and stars together.

  • Handle unstable SGP4 TLEs.

  • Add TensorFlow 2.4 Docker build file.

  • Add debug output for pristine images of targets and stars.

0.9.1

  • Calculate POPPY input wavefront resolution to avoid PSF aliasing.

  • Add support for additional FITS image data types (int16, uint16, int32, uint32, float32).

  • Add batch processing to transform_and_add_counts to support batch processing of stars.

  • Add auto option to calculate temporal oversample factor based on star velocities.

  • Add option to turn off serializing config data to pickle file (save_pickle).

  • Add option to turn off png movie output (save_movie).

  • Add crop_and_resize and flip image augmentation.

  • Set pixels with values beyond the pixel data type’s capacity to the maximum value for that data type.

  • Add lognormal function to generate a distribution with a true target mean.

  • Fix issue with sidereal track.

  • Fix issue with fragment velocity not being randomly sampled.

0.9.0

  • Add Physical Optics Propagation in Python (POPPY) PSF generation.

  • Add PSF augmentation with $pipeline replacement key.

  • Add $function and $compound replacement key.

  • Add ability to generate stray light from a $function replacement key.

  • Add built-in 2D polynomial image generator for stray light, polygrid2d.

  • Add built-in cosine fourth image generator for irradiance falloff, radial_cos2d.

  • Add built-in sine wave image generator for fix pattern noise, sin2d.

  • Add built-in image generator from AstroPy model, astropy_model2d.

  • Add built-in image augmentation, scatter_shift and scatter_shift_polar.

  • Add $cache replacement key (caching works for PSF and $function).

0.8.3

  • Fix new Skyfield incompatibility.

0.8.2

  • Prefix replacement keys with $ in SatSim configuration file.

  • Add option to scale collision fragments by cosine of the exit angle.

0.8.1

  • Add astrometric metadata into FITS header

  • Refactor WCS library

  • Add option to flip images about x or y axis

  • Add option to refresh stars for each frame

  • Add RPO from TLE generator

0.8.0

  • Add two body propagator

  • Add object create, delete, and update events

  • Add collision generator

  • Add breakup generator

  • Add ref keyword to configuration

  • Add key keyword to import configuration

  • Refactor astrometric library

0.7.2

  • Add option to specify star and obs velocity in polar coordinates

0.7.1

  • Add option to turn off shot noise: sim.enable_shot_noise: true

  • Add option to turn off annotation boxes in image: sim.show_obs_boxes: true

  • Add option to specify velocity in arcseconds: sim.velocity_units: arcsec

  • Fix PNG output threading issue

0.7.0

  • Add function pipelines to support variable target brightness

0.6.1

  • Fix built-in generators not included in distribution

  • Add dockerfile

0.6.0

  • Add configuration import.

  • Add configuration generator functions.

  • Add built-in generator for breakups.

  • Add built-in generator for CSOs.

  • Add built-in generator for loading TLE files.

0.5.0

  • Runtime optimization.

  • Add parallel processing and multi-gpu utilization.

  • Add option to limit gpu memory usage.

0.4.0

  • Add signal to noise calculation for target pixels.

0.3.0

  • Add support for two line element set SGP4 satellite propagator.

  • Add support for rate and sidereal track from topocentric site.

0.2.0

  • Add support for SSTR7 star catalog.

0.1.1

  • Add target position to annotation file.

  • Updates to run GitLab CI.

0.1.0

  • First release.