DIRSIG5 2024

DIRSIG5 2024.50

  • Important Compatibility Related Notes

    • The Linux release was migrated from a RHEL 7 to a RHEL 8 build host.

      • The executables will not run on RHEL 7 (or CentOS 7, etc.) that only have libc 2.17 or older installed.

      • The updated Linux release includes new MPI adaptors for OpenMPI (both 3.x and 4.x) and MPICH (both 3.x and 4.x).

      • The MuSES TDFIO library was updated to 2024.1.1.

    • The macOS ARM64 (Apple Silicon) and Intel releases were migrated to macOS 14 "Sonoma" (SDK 15.0).

      • The executables will not run on macOS versions older than 14.7.

  • Features

    • The graphical image viewer and command-line image_tool utility now feature options to color zero and NaN ("not a number") valued pixels (the input data value, not the scaled value).

    • Improvements to the image_tool utility.

    • Improvements to scene geometry support via GLIST files:

      • Support for more 3D geometry formats was introduced via the Asset Importer library. A variant was added to the Parking1 demo that utilizes a combination of OBJ, FBX, Collada DEA and GLTF input geometry files.

      • In addition to object-level material overrides, the GLIST file now supports instance-level material overrides as well.

      • More robust error checking for invalid dynamic instances setups were added to the scene compiler.

      • Introduced an option to store large numbers of static instances in a new binary file that greatly reduces file sizes and load times.

    • Introduced an easier way to configure simulations utilizing scenes composed of many "tiles" by loading all the scene files from a specified folder.

    • Improved the FastClouds plugin

      • The user can now specify a reflectance scaling option.

      • The user can now specify the pixel size in decimal degrees in lat/lon.

      • A tiling scheme was added to handle cases when the image is smaller than the requested window/globe.

    • The normal map now supports an optional scaling factor (0 → 1, defaults to 1) that is commonly used and/or available in other modeling tools.

    • More robust error checking on the inputs to the parameterized configuration option for the MODTRAN Tape atmospheric model backend was added.

  • Graphical User Interface

    • JSIM Editor

      • The editor now supports the option to specify a scene folder that can contain one or more scene files (commonly used in wide-area, tiled scenes).

    • Image Viewer

      • The image viewer will now automatically open the image file if the tool is launched from the command-line with a single image file supplied.

      • The image viewer now supports the new "zero color" and "nan color" feature in the underlying image_tool utility (see the --zero_color and --nan_color options to the convert tool).

  • Extra

    • The Blender add-ins for DIRSIG were further improved to better facilitate the use of Blender as a mechanism to convert scenes from conventional representations into ones that can be ingested into DIRSIG (perhaps with some manual edits).

      • See the PDF formatted README file in the extra/blender/4.0x folder for more information.

  • Documentation

    • A new 3rd Party Dependencies document has been added that captures the libraries utilized by DIRSIG.

    • A new table in the image_tool manual defines the list of available output image formats.

  • Demonstrations

  • Bugs

    • Fixed a bug where the spin engine in the Flexible Motion model did not correctly handle rotations about an axis other than +Z (e.g., [0,0,1]).

    • Fixed a bug where scene-less simulations combined with a sensor with integration time resulted in an error about accessing a "null scene".

    • Fixed a bug where multiple geometric instances didn’t correctly contribute to the overall abundance in a pixel.

    • Fixed a bug with atm_builder that could produce crashes when building an atmosphere for a simulation that contained duplicate spectral states (e.g., arrays using the same spectral samples).

    • Fixed a bug where scene2hdf would repeatedly process the same scene file if it appeared in the input scene list multiple times (for example, when a scene is included multiple times with unique scene offsets).

    • Fixed a bug where image_tool convert (primarily on Linux) did not properly support many of the common image file formats.

DIRSIG5 2024.28

  • Important Compatibility Related Notes

    • The scene2hdf scene compiler was updated to report warnings regarding invalid parameters for the THERM temperature model.

      • This includes cases such as the thermal conductivity being less than or equal to 0, thickness less than or equal to 0, etc.

      • Scenes that compiled cleanly with previous versions of DIRSIG may now produce warnings or errors.

  • Features

    • Introduction of the new, graphical image viewer.

      • This image viewer is primarily a graphical wrapper around the existing command-line image_tool utility.

      • This is significantly faster and more powerful than the DIRSIG4-era tool, which is still available as image_viewer4.

      • The new data tool was added to the image_tool utility to facilitate displaying the raw image data.

    • Introduction of the new LightCurve sensor plugin.

      • This plugin streamlines the generation of 1D light curves for objects as a function of time.

      • A common application is computing the light curve for an orbiting object (e.g., a satellite) for space domain awareness applications.

    • Improvements to the BasicPlatform sensor plugin

    • Improvements to the FourCurveAtmosphere sensor plugin

      • The default database was expanded to include more declination angle samples.

      • The plugin will now search your Documents/DIRSIG/atmospheres folder for alternative database files (avoids needing to hard code paths to database files).

      • The database builder tool now supports the nominal altitude as a command-line option, allowing a single confguration to be used to generate databases for different altitudes.

      • A MWIR and LWIR database configuration file for the database builder is now included in the $DIRSIG_HOME/lib/data/atm folder.

    • Improvements and additions to the Earth Model Plugins

      • Improvements to the EarthGrid plugin allow the user to provide an RGB background image for a portion of the Earth (defined by a latitude and longitude box).

      • Introduction of the FastClouds plugin, which introduces a mechanism to use 2D cloud masks to model large area cloud fields.

    • Improvements to the FlexibleMotion model.

      • The velocity and look at orientation (rotation) engines were improved to resolve ambiguities in orientation (see the new/updated <constraint> element).

      • The spin orientation (rotation) engine now supports the rotation axis being defined in the ECEF coordinate frame.

    • Addition of new truth collectors

    • General Features

      • The parameterized atmospheric model backend for MODTRAN now allows the user to specify the band model file to use (see the new band_model_name variable).

      • The new "directional" collector type was added to the PointCollectors plugin, which samples a user-supplied solid angle.

  • Graphical User Interface

    • Introduction of the new, graphical image viewer.

    • Added the ability to import multiple DIRSIG3-era spectral response files at a time in the Simple Capture Editor.

    • The MODTRAN band model can be overriden in the NewAtmosphere editor when using the parameterized MODTRAN input description.

  • Data

    • Added new DIRSIG3-era spectral response files for NASA’s Landsat8, MAXAR’s WorldView-3, Planet’s SuperDove and Planet’s SkySat satellites.

    • Pre-built, alternative FourCurveAtmosphere databases for the MWIR/LWIR and higher altitudes are available via myDIRSIG.

  • Documentation

  • Demonstrations

    • The EarthShine1 demo was updated after it was discovered the previous setup was invalid once a bug was discovered and addressed (see Bugs below). This included a change in the collection geometry and enabling hypersampling on the target sphere to better capture diffuse reflections of the Earth.

    • The new LightCurve1 demo was introduced to, which shows how to use the new LightCurve sensor plugin.

    • The new EarthClouds1 demo was introduced to, which shows how to use the new FastClouds plugin.

  • Bugs

    • The longitude truth collector label (used in the truth image files) indicated the value was +W longitude, when it is +E (this was recently introduced in the 2023.52 release).

    • Fixed a problem with the BasicPlatform DataRecorder instrument where it was outputting invalid Euler rotation angles.

    • Fixed a problem with hypersampling in BasicPlatform not correctly engaging when using a geolocated platform.

    • Fixed a range problem with scenarios using the EarthGrid plugin, that always placed other objects in front of the Earth.

DIRSIG5 2023

DIRSIG5 2023.52

  • Under the hood

    • The scene data model (HDF) lat/lon/alt was increased from single to double precision. This improves pointing precision for high altitude (exo-atm) sensors.

    • A series of optimizations have increased the run-time performance of simulations using multiple scenes.

    • An optimization was added to improve performance for simulations employing large numbers of user-defined sources.

    • The internal ephemeris plugin API now describes exo-atm sources (Sun and Moon) as ECEF locations with velocities rather than in terms of a scene relative vector.

      • This improves multi-scene simulations and allows for location dependent solar/lunar geometries.

    • DIRSIG5 can now be run "scene less", meaning a simulation using just the EarthGrid plugin is valid.

    • The BasicPlatform sensor plugin now shoots ECEF rays when a non scene ENU coordinate system is used for motion. This improves pointing precision for high (exo-atm) sensors and introduces flexibility for scene-less simulations.

  • Features

    • Space situational/domain awareness (SSA/SDA) type simulations are now supported in DIRSIG5.

    • Environment variable support was added for external program paths

      • In an effort to improve portability of simulations, the MuSES plugin and MODTRAN backends now support using environment variables to avoid hard-coded paths to executables, data directories, etc.

      • An environment variable is indicated as a string wrapped by ${ and } (e.g., ${MUSES_EXE}, ${MODTRAN_EXE}, etc.). If an incorrectly formatted variable is found, or the indicated variable does not exist, an error will occur.

    • Improved support for MODTRAN6

      • The DIRSIG4-era make_adb atmospheric database builder will now work with MODTRAN6 without the need for the script wrapper required in previous releases.

      • The DIRSIG5-era Modtran Tape backend used by the NewAtmosphere and FourCurveAtmosphere atmospheric database builders will also now work with MODTRAN6 without the need for the script wrapper required in previous releases.

      • The new MODTRAN6 JSON backend used by the NewAtmosphere and FourCurveAtmosphere atmospheric database builders was introduced, which utilizes the modern JSON input interface to MODTRAN6.

    • The Modtran Tape backend that is used with atm_builder and fourcurve_builder now includes a new "parameterized" configuration option:

      • This allows the user to define a basic MODTRAN configuration without needing to pre-build a tape5 file. Note that this feature can be used with MODTRAN6 as well.

    • An option to "remove the sensor path" was added to the NewAtmosphere and FourCurveAtm atmospheric radiative transfer plugins.

      • This is a run-time option to set the radiance and transmission to 0.0 and 1.0 respectively for the first path segment between the sensor and a scene object. This effectively changes what is usually a sensor reaching radiance to a scene leaving radiance.

    • Improvements to the scene_tool utility to make it easier to lookup various truth indexes.

    • The DeltaReflectance and DeltaTransmittance surface optical properties were introduced.

    • The Tabulated and Commanded mount models in BasicPlatform now support platform-relative translation.

    • The DIRSIG5 command-line schedule modification options now include an --end_capture option.

      • This option can be used alone or combined with the --start_capture to simulate a subset of captures in a multi-capture simulation.

    • Graphical User Interface (GUI) improvements when working with JSIM-based simulations.

  • Deprecations and Functional Changes

    • The DIRSIG5 command-line instance report option is no longer supported.

      • This old and tedious method for relating geometry truth indexes back to input scene geometry has been replaced by the new lookup tool in the scene_tool utility.

    • The ClassicExtinction optical property was changed from being internally modeled with a "delta" function (light emerges from the back side going in the same direction) to a "diffuse" function (light emerges from the back side going in a random direction in the hemisphere).

      • This optical property was primarily used in DIRSIG4 and many older scenes to model vegetation transmission (leaves) and the updated diffuse treatment more accurately captures how light interacts with vegetation.

      • However, this optical property was also used in some cases to model materials such as "glass". With this change, the glass will now be appear "frosted" as light paths will emerge from the backside going in random directions rather than straight through. To model a material like glass consider using the DeltaTransmittance property instead. See the updated versions of the BundledObject1 and Parking1 demos for working examples.

  • Documentation

  • Demonstrations

  • Bugs

    • Fixes to scene2hdf to correctly handle multiple TDF files in a single scene.

    • Improvements to the BasicPlatform sensor plugin:

      • Fixed the built-in detector model when the minimum number of electrons is not zero.

      • Fixed the aperture not changing the output units when not using the detection model.

      • Fixed the STK report file readers to now allow the "number of points" variables to be a decimal value (some versions of STK write the files this way).

    • Improvements to the graphical user interface for JSIM files:

      • Fixes to the BasicAtmosphere JSIM editor.

      • Fixes to the BasicPlatform JSIM editor.

      • Improved the layouts of many of the JSIM editor windows to work better on smaller screens.

    • Fixes to the Earth model plugins.

    • Fixes to thermal water plugin.

    • Fixes to path tracing deviant weighting with sources.

DIRSIG5 2023.12

  • Features

    • Introduction of the new vdb_tool command-line program, which provides ways to create, modify and interact with OpenVDB files containing voxelized (volumetric) geometry.

      • This includes a replacement for the stand-alone blackadar plume model introduced in the previous release.

      • It also includes tools to convert DIRSIG4-era RegularGrid files and arbitrarily sampled ASCII/Text XYZ files.

    • Introduction of the new ems_tool command-line program, which provides ways to generate, manipulate and interact with DIRSIG emissivity files.

    • Introduction of native AutoDesk FBX support.

      • An FBX file can now be used as a source of facetized geometry in a GLIST file. See the updated Parking1 demo for an example.

      • The new FBX export tool was added to the scene_tool utility, which will produce a FBX file for the scene. This FBX currently does not contain materials, but it does capture the geometry hierarchy, including dynamic instance motion that can be previewed in 3D tools including Blender, Maya, etc.

    • Improved support for abundance truth in multi-scene simulations.

      • Material abundances are now correctly gathered across multiple scenes. Additionally, the user can use the new scene names feature to indicate that they only wish to collect abundance for a specific scene in a multi-scene simulation.

      • Tagged abundances are now correctly gathered across multiple scenes.

    • Improvements to the scape_tool utility:

      • An option was added to specify the material ID for all the facets in the resulting terrain.

      • An option was added to automatically add a simple 2D UV coordinate system to all the facets in the resulting terrain.

      • The output OBJ file now utilizes shared vertices, which results in significantly smaller OBJ files.

    • Introduction of support for "default bands" in the ENVI image files produced by DIRSIG.

      • This allows the user to optionally define what bands (either 1 or 3 bands can be specified) will be automatically displayed upon an initial load of the image in ENVI and other electronic light table (ELT) applications.

      • The DIRSIG image_tool convert mode will automatically use these default bands if the --bands option is not supplied.

    • Changes to the default spectral coverage windows.

      • The upper wavelength in the predefined "SWIR" windows in scene2hdf was extended from 2.52 microns to 2.55 microns.

      • The default FourCurveAtmosphere database was update to have a broader spectral range, now supporting 0.35 → 2.55 microns (previously 0.38 → 2.52 microns).

  • Migration of the command-line interface (CLI) parsing for several of the tool-based utilities to a new backend that improves modularity and ease of use.

  • Improvements to the Graphical User Interface (GUI)

    • The Output tab of the Simple Capture Editor now lets you specify the "default bands" to be automatically displayed in ENVI and other ELT applications.

    • The DIRSIG image viewer will now pre-select (but not automatically display) the "default bands" in the ENVI image file (if supplied).

    • The initial state of the Clock tab in the Focal Plane Editor was updated to allow the user to immediately set the integration time and rolling shutter variables.

  • Documentation

  • Demonstrations

    • Introduction of the new Brdf3 demo, which focuses on the impacts of surface roughness in a common BRDF model.

    • Introduction of the new SubPixelObject2 demo, which focuses on hypersampling full-fill targets that have small (sub-pixel) features. In this case, a hot spot on the hood of a car.

    • Updates to the Muses1 demo to note differences between DIRSIG4 and DIRSIG5 import mechanism.

    • Updates to the PlumeVDB1 demo to include the original LWIR simulation looking at an emissive SF6 plume and new a SWIR simulation looking at an absorptive methane (CH4) plume. The README was updated to note the replacement of the old stand-alone blackadar utility with the new vdb_tool.

    • Updates to the Parking1 demo to include an alternate version where all the OBJ files have been converted to FBX.

Review all resolved issues in Bugzilla.

DIRSIG5 2022

DIRSIG5 2022.48

  • Deployment

    • The MacOS application bundle is now code signed and notarized (which which confirms for the user that the application was created by RIT and has not been modified by a 3rd party).

      • This enables the Apple Silicon (ARM64) release for M1 and M2 machines to run without needing to disable System Integrity Protection (SIP).

      • See the updated notes in the installation manual for more details.

    • The Windows installer is now code signed, which confirms for the user that the application was created by RIT.

      • However, Windows Defender might still flag the installer as an "unrecognized app" and require additional user authorization to install. See the updated notes in the installation manual for more details.

  • Features

    • The graphical JSIM editor has been improved to allow the user to run simulations as well as edit them.

      • The layout of this tool was changed to use modal, popup editor windows.

      • A DIRISG4-era .sim file can be migrated to a DIRSIG5-era JSIM file.

      • The order of plugins can now be modified so that plugin overrides can be managed.

      • The unknown (user-defined) plugin editor now provides basic JSON formatting checks.

      • Minimal support for the medium_list is included.

      • The editor has a basic "unsaved changes" check before running.

    • Introduction of the MuSES plugin, which provides an improved, Level-1 integration between DIRSIG and the MuSES signature prediction model.

      • This plugin ensures that the location, orientation, date, time, materials and weather are automatically synchronized between the two models.

    • Introduction of the PlumeVDB plugin, which provides a way to import external plumes (factory stacks, cooling towers, etc.) into DIRSIG using the OpenVDB voxel description.

      • This also includes a port of the DIRSIG3 and DIRSIG4 era puff-based plume model derived from Alfred Blackadar. The blackadar plume utility allows the user to generate single species plumes that can be assigned absorption and/or scattering properties via the PlumeVDB plugin.

    • Introduction of the scene_tool utility to extract information from compiled scenes (aka scene HDF files).

    • Introduction of the facet_tool utility to convert and manage facetized geometry files.

    • Introduction of the direct Curve Map, which allows the user to treat an image as an index map into a curve database.

    • Improvements to the atm_builder utility.

      • The tool now supports a user-supplied list of altitudes to use rather than ones derived from the various scene altitudes and sampling (see the --altitude_list option).

      • The tool now support command-line options to override the default sky sampling range and interval (see the --sky_zenith_sampling and the --sky_azimuth_sampling options).

    • Improvements to the atmospheric database builders (make_adb, atm_builder, etc.) to now run a suite of MODTRAN verification tests upon startup to help the user diagnose configuration issues.

    • Improvements to the image_tool conversion mode

      • The --autoscale=none is now always a manual scaling defined by the optional --gains and --biases arguments (the respective defaults for those are now 1 and 0, respectively). Before some syntaxes would still result in a min/max scaling.

      • The new --output_filename option was added to let the user specify the name of the output file.

    • Improvements to the ChipMaker plugin

      • Channel descriptions can now include gain and bias ranges, which will be used to scale the normal radiance or reflectance outputs to different units or to N-bit output (see here for more details).

      • Channel descriptions can now include a simple additive noise range. This noise is applied after the optional internal scaling operation (see here for more details).

      • The user can now define one or more processing steps as part of the configuration. These steps can be used to trigger any common command-line task (post-processing, format conversion, etc.) on the image data produced for each chip (see here for more details).

    • Improvements to the Graphical User Interface (GUI)

      • The instrument editor now provides access to the optional aperture parameters and lens distortion configurations.

      • The focal plane editor now lets the user enable time-delayed integration and to enable hypersampling.

      • Improvements were made to address style sheet overrides when using Dark Mode.

    • Improvements to the (experimental) inline processing feature in the BasicPlatform plugin

      • The original input filename syntax has been replaced by a string variable that is automatically replaced with the current filename.

      • A more complex example of generating a video file as part of the simulation is now described in the plugin manual and an example included in the TrackingMount1 demo.

    • Improvements to the OrthoImage plugin to optionally include truth data in the output data cube.

    • Addition of the instance report option to the DIRSIG5 run-time, which will produce a JSON report that can be used to link various truth indexes back to base geometry and instance information.

    • Addition of absolute time support and time interpolation to the .til (map time sequences) files.

    • ENVI spectral library (.sli) support was added to the SimpleReflectance and SimpleTransmittance optical properties and the new Curve Map.

      • The sli_tool utility was introduced to help the user create and manage these SLI files.

    • Jitter is now supported in DIRSIG5 when using the FlexMotion model for in-scene object motion.

  • Documentation

  • Demonstrations

Review all resolved issues in Bugzilla.

DIRSIG5 2022.12

  • Features

    • Native support for Apple Silicon (ARM64) processors.

    • Simplified deployment of the MPI-enabled version of DIRSIG5

      • Rather than a separate set of executables, MPI is now enabled with run-time option. See the Parallel DIRSIG5 Guide for more information.

    • An important difference in how DIRSIG4 and DIRSIG5 model the spectral component of LIDAR transmitters (lasers) has been documented and addressed in the LIDAR demos.

    • Improved console output controls

    • The BasicPlatform plugin has a new option to easily scale the resolution of all the focal planes in a platform from the command-line.

    • The PointCollectors plugin now supports a directional collection mode in addition to the hemispherical and spherical collection modes.

    • A new editor for JSIM simulations has been introduced.

      • Although not fully capable yet, this editor allows users to create and edit JSIM configurations.

      • A short tutorial has been added to introduce the user to the basics of using the editor.

    • Replacement of the old envitopnm utility with the new image_tool utility.

      • This more powerful tool allows the user to process images in bulk (rather than indidividually) and directly convert them to JPEG, PNG, etc.

    • Entire GDB and OBJ files can now be assigned a single temperature in a GLIST file via the <temperature> element.

    • Introduction of the bundle inventory, which is a collection of pre-built, bundled object scene assets that can be easily added to scenes.

  • Documentation

    • The old "DIRSIG4 Manual" has been retitled the DIRSIG4 Command-Line Guide.

    • The old "DIRSIG5 Migration Manual" has been retitled the DIRSIG5 Command-Line Guide and reworked:

    • The DIRSIG4-era atmosphere documentation was improved.

      • A new manual for the BasicAtmosphere plugin was introduced, which describes the "SimpleAtm", "UniformAtm" and "ClassicAtm" DIRSIG4 modes supported by this plugin

      • A new manual for the make_adb tool was introduced that attempts to capture how the tool interacts with MODTRAN (including a table of MODTRAN variables modified by the tool), the various configuration options (the "old" MODTRAN installation configuration file vs. profiles in the user settings), options in the .atm file (including an example of an internally stored "tape5" file) and command-line options.

      • A new manual for the ADB file format was introduced.

    • The major overhaul of the material documents has been completed:

    • A manual for the new image_tool utility was introduced.

    • Unit conversions were corrected and improved in the THERM temperature solver documentation.

    • The GLIST manual was updated to document the minscale and maxscale options to the random fill instancing options.

    • The scene2hdf manual was updated to document the DIRSIG_CACHE_DIR override.

    • The BasicPlatform plugin manual was updated to include a section of related documents for platform motion, mounts, truth, etc.

    • The FAQ was updated with a few clarifying questions and anchors for easy linking.

  • Demonstrations

  • Bugs

    • Fixed a bug where large scene map images could not be loaded.

    • Fixed a bug where RGB images would incorrectly trigger a recently added "high bit depth" error check.

    • Fixed a bug where a BasicPlatform plugin configuration with TDI would trigger a range error in the platform motion.

    • Fixed a bug with path radiance and transmission discontinuities for sensors viewing the horizon.

    • Fixed a bug in how DIRSIG5 models RGB maps that would result in a spectral artifact at 0.500 and 0.600 microns.

Review all resolved issues in Bugzilla.

DIRSIG5 2021

DIRSIG5 2021.42

This release produced shortly after the 2021.40 release was produced to address some important bugs in the graphical user interface (GUI).

  • Bugs

    • Fixed a bug where the user could not open or save a PPD file from a simulation in the GUI.

    • Fixed a bug where the right-click menu in the "Component Browser" presented the user with invalid options for an empty component group.

    • Fixed a bug where the output log from the GUI would be incomplete or empty if the simulation failed.

Review all resolved issues in Bugzilla.

DIRSIG5 2021.40

  • Features

    • Updated Ray-Tracing Core

      • The internal ray tracing capabilities have been upgraded to the latest version of Embree (3.13).

      • All DIRSIG4-era built-in (aka "primitive") geometry types are now supported in DIRSIG5.

      • Bezier curve sets can now be ray traced, which allows for direct modeling of some vegetation (e.g., grass blades).

      • Improvements have been made to shadow ray performance.

    • Temperature Prediction Improvements

      • The iterative Balfour model has been improved to reduce noise and mitigate stepping artifacts in thermal shadows.

      • THERM is under active development, but is now supported in DIRSIG5.

        • All materials currently use 4 hours of history (adaptive history under development).

      • THERM parameter maps are now supported in DIRSIG5.

    • ChipMaker Improvements

      • The plugin was updated to leverage the new scene tagging feature to facilitate a new workflow that allows targets and backgrounds to be combined on-the-fly.

      • This introduces a fundamentally new way to generate training data by combining many targets and backgrounds.

    • Graphical User Interface Improvements

      • DIRSIG has been upgraded to use Qt6 on all platforms, which will support future UI development.

      • The run-time output of DIRSIG can now be routed to an output file from the run dialog or saved after the fact from the right-click menu in the output panel.

      • Items in the component browser may now be deleted via the right-click menu.

      • For DIRSIG5 simulations, a scene recompile can now be triggered from the run dialog.

    • Improved pseudo random number generation (RNG)

      • The internal RNG handling was refined to reduce artifacts and improve performance.

    • New Image Analysis/Conversion Tool

      • The new image_tool program was introduced as a replacement for envitopnm and image_analyze utilities.

      • It is intended to serve as a tool to interact with DIRSIG output images, for converting them and performing some common analysis tasks.

      • Both envitopnm and image_analyze are now deprecated and will be removed in a future release.

    • Improved Raster Image Handling

      • A new class of plugins was introduced to handle raster image reading, which allows DIRSIG’s image reading capabilities to be extended.

      • The ENVI image plugin has yielded significant runtime improvements when loading these image file types in scene2hdf and image_tool.

      • This new plugin class will (eventually) allow users to add support for additional formats/remote storage of input image files.

    • Non-raster source truth has been expanded to improve traceability.

    • The makewth.py tool has been updated with more international coverage.

    • The object_tool utility can now read ModelMan FACET files.

  • Demonstrations

  • Bugs

    • Fixed an issue where RGB map reflectance curves went to 0 outside the visible instead of using flat extrapolation. Use of RGB maps is not recommended outside of visible simulations.

    • Fixed a few issues in make_adb relating to precision, angle ranges and the fast sky mode.

    • Fixed an issue with multiple scenes defined using tie points.

Review all resolved issues in Bugzilla.

DIRSIG5 2021.27

  • Features

    • Support for a 5-parameter lens distortion model was introduced to the pinhole camera approach used in the BasicPlatform sensor plugin. See the new Distortion1 demo for an example.

    • Improvements to the SpiceEphemeris plugin:

      • The user can now override the default SPK (DE-420 ephemeris), PCK (planetary constants) and LSK (leap second) kernel files used by SPICE in this plugin via the JSIM configuration.

      • The Sun/Moon position update notifications generated by the plugin was improved. Although the plugin still updates the position of the Sun and Moon for every temporal state change (e.g. image frame), the user can now control how often update messages are sent to the console output (see the update_delta variable in the JSIM configuration).

    • Boundary layer meteorological data (aka weather) support in DIRSIG5 has been migrated into a new set of plugins.

    • The fourcurve_builder companion tool for the FourCurveAtmosphere plugin is now MPI-enabled for users that want to construct alternative databases using large numbers of MODTRAN simulations.

  • Demonstrations

    • New Demos

      • Distortion1 is a demo showing how to use the 5-parameter lens distortion model in the BasicPlatform sensor plugin.

      • WeatherPlugins1 is a demo showing how to configure various weather plugins in DIRSIG5.

  • Bugs

    • Fixed a bug where the FlexMotion model used for BasicPlatform did not deal with parallel line-of-sight (LOS) and constrain vector cases.

    • Fixed a bug where the default body quaternion in the FlexMotion model was not properly initialized.

    • Fixed a bug in DIRSIG4 where the self-emission was lacking a cosine term for the view angle.

    • Fixed a bug where the scene compiler would decouple a bump map from geometry that is also assigned a material map.

Review all resolved issues in Bugzilla.

DIRSIG5 2021.13

  • Release Packaging

    • DIRSIG5 releases for either OpenMPI and MPICH are now available (previously only OpenMPI builds were produced).

  • Scene Compilation

    • The scene2hdf tool was completely rebuilt from the ground up to eliminate the DIRSIG4 code that it was previous based on. The new compiler is significantly faster and uses less memory for some of the random fill instance mechanisms. For more details, please consult the update scene2hdf manual.

    • Coinciding with the scene2hdf rewrite, the compiled scene format was overhauled. This change in format does break backward compatibility, so scenes that were compiled with previous releases will need to be recompiled.

    • The new compiled scene format now supports the propagation of material specific temperature models through material and mixture maps.

  • Features

    • LADAR/LIDAR

      • In the previous release this modality was considered to be experimental in DIRSIG5. This modality has been extensively exercised during the last development cycle and is considered to be operational in DIRSIG5.

      • These simulations can now be run with the MPI-enabled versions of DIRSIG5, but require the user to use the Unique Frame per-Process (UFP) scheduling mode.

    • "Four Curve" Atmosphere Plugin

      • The lower fidelity but physics-driven FourCurveAtm atmosphere plugin was updated to capture azimuthal variances in path radiance.

    • New Ephemeris Plugins

      • The ephemeris models responsible for computing the solar and lunar geometry as a function of time were migrated from shared components in the atmosphere plugins to stand-alone plugins. More information about the available ephemeris plugins can be found here.

  • Graphical User Interface

    • The simple capture method interface in the Platform Editor now gives the user access to change the output data type, including integer data types. Note that the unsigned integer types require the user to use the channel gain and bias mechanism, data-driven array amplification mechanism, etc. options to scale the radiometric values computed by the model into integer values. The currently supported data types include:

      • 64-bit floating point (aka double, the default)

      • 32-bit floating point (aka single)

      • 32-bit unsigned integer (aka uint32)

      • 16-bit unsigned integer (aka uint16)

      • 8-bit unsigned integer (aka uint8)

  • Demonstrations

    • Improved Demos

      • Indoors1 is demo that focuses on multi-bounce illumination effects from interior user-defined sources and external atmospheric sources. This demo was updated to feature a more complex scene that highlights the efficient, multi-bounce light transport in DIRSIG5.

      • LidarUserPulse1 is a demo that shows how to use a user-defined temporal pulse profile in a lidar transmitter.

    • New Demos

      • LidarRetro1 is a demo that reproduces the expected strong return from a retro (corner) reflector with a LIDAR system.

      • SphericalCollector2 is demo that shows how to use the SphericalCollector sensor plugin to emulate an optical goniometer than can quickly collect BRDF type measurements of complex surfaces.

      • MacbethColorChecker1 is a demo that contains a bundled object of the industry standard Macbeth Color Checker.

      • TriBar1 is a demo that contains a bundled object of the industry standard USAF Resolution Target (sometimes referred to as the USAF "tri-bar" target).

  • Bugs

    • Fixed a bug where the LAS point cloud writer did not include the "GeoKeyDirectoryTag" variable length record, which would upset some LAS point cloud readers.

    • Fixed a bug where high-standoff platform motion was not correctly interpolated for small time scales.

Review all resolved issues in Bugzilla.

DIRSIG5 2020

Starting in mid-2020, the DIRSIG releases moved from the Major.Minor.Revision naming scheme to a date-based naming scheme. The version is now identified by a Year.Week.Update and the short hash from our GIT repository.

At this time, DIRSIG5 releases come bundled with the latest DIRSIG4 executable. DIRSIG4 development has ceased, but major bugs are being addressed for the time being until the capabilities planned for migration into DIRSIG5 are completed.

DIRSIG5 2020.43

  • Features

    • General

      • The scene2hdf tool now has an explicit option to specify alternative spectral sampling for the compiled scene via an external file.

      • The BasicAtmosphere plugin now correctly handles internal (embedded) weather data in the .atm file.

      • Improved the support for the built-in image viewer to display unsigned 8-bit, 16-bit and 32-bit integer data types.

      • Major improvements for assigning volumetric properties to primitive (built-in) geometry in DIRSIG5. See the updated ExtinctionProp1 demo for an example.

      • Introduction of "bundled materials", which allows you to create individual files that contain complete material descriptions. Centralized collections of these material descriptions can be created and then imported into multiple material database file for a scene or object bundle. See the new BundledMaterials1 demo for an example.

    • LADAR/LIDAR

      • This is the first public release of DIRSIG5 with lidar support. It should still be considered experimental but all the lidar demos are generally working at this time. Improvements in performance, the back-end detector models, etc. are still ongoing.

  • Demonstrations

    • The DIRSIG4 and DIRSIG5 demos in the main demo index has been merged into a single set. The D4 and D5 compatibility "badges" with each demo indicate which version of DIRSIG is supported.

    • Improved Demos

      • The ExtinctionProp1 was updated to better demonstrate assigning volumetric properties to primitive (built-in) geometry in DIRSIG5. Note, this demo is no longer compatible with DIRSIG4.

    • New Demos

      • ColorFilterArray1 is a demo that shows how to use the color filter array (CFA) options built into the BasicPlatform plugin, including Bayer and Truesense patterns.

      • BundledMaterials1 is a demo that shows how to create and use "bundled materials".

      • LidarUserBeam1 is a lidar demo that shows how to incorporate a user-defined spatial (transverse) beam profile.

      • LidarMultiStatic1 is a lidar demo that shows how to model a multi-static (multi-vehicle) collection scenario. It features a single transmitter and two receivers distributed on three separate vehicles.

  • Bugs

    • Fixed a bug where the image filenames in the dry run output did not match those that would be produced during the simulation.

    • Fixed a bug where a platform staring at a location would appear to "bounce" due to a problem in the dual quaternion screw linear interpolation (ScLERP) routine when the differences in rotation are small from entry to entry.

    • Fixed a bug with the FlexMotion waypoint orientation engine and Euler angle and quaternion orientation engines when a single data entry was provided.

    • Fixed a bug related to parsing an optional external spectral sampling file for the scene2hdf utility.

    • Fixed a bug where the DIRSIG5 material index truth is off by 1 compared to DIRSIG4 and the material_report.txt.

    • Fixed a bug where the emissive objects where being reflected by surfaces with zero reflectance.

    • Fixed a bug when using the --capture option with a multi-focal plane sensor with co-temporal (equal) capture times in the BasicPlatform plugin.

    • Fixed a bug with inconsistent capture counts for non-zero length tasks.

    • Fixed a bug that addresses the correct importing/storing/loading of the internal (embedded) weather data in the .atm file by the GUI.

    • The origin of rays for DIRSIG4 is now the focal point of the camera (matches DIRSIG5 BasicPlatform plugin, Maya, etc.) rather than the focal plane.

    • The graphical material editor was incorrectly saving SimpleReflectance material properties to the .mat file.

Review all resolved issues in Bugzilla.

DIRSIG 4.7

DIRSIG 4.7.5.17770

Release Date: Thu Jun 15 18:48:18 EDT 2018

  • General

    • Improvements to time precision management within the motion models.

    • Improvements to tape5 reading/writing.

      • Verified against 95+ tape5 examples included with MODTRAN6 (except local plume examples, which would be invalid anyway).

    • The Atmosphere Editor was updated to provide access to configuring a fixed lunar ephemeris (only access to the solar ephemeris was provided before).

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.7.4.17540

Release Date: Wed Dec 12 13:49:24 EST 2017

  • General

    • Further updates to improve the ability to bundle objects including bundle-relative paths for several mapped optical properties, including spectral reflectance maps, RGB reflectance maps and mixture maps. Source PSD files are also correctly searched for in the bundle folder.

    • Improved material file configuration of bump maps.

    • Several updates to tape5 parsing to improve support for both historical features and advanced options added in MODTRAN5.

      • Fixed a bug with the Card 2 VIS, WSS, RAINRT and GNDALT variables being parsed incorrectly.

      • Fixed a bug with the Card 2C2 parsing.

    • Fixed issues with null materials over water.

    • Several of the GLIST fill options were updated to use local random number generators for all aspects of object insertion.

    • Improved the error checking logic for solver requirements on proxy materials.

    • Migrated the hyper-sampling option from the adaptive pixel sampler to the central sampler, which yields more stable results and insures the truth is valid.

    • Added new features to the scene file and Scene Editor for tracking the wavelength windows appropriate for the scene and (optional) minimum and maximum GSDs for the scene.

  • LADAR/LIDAR

    • Improved the fidelity of the dark count rate (DCR) tests in the Advanced GmAPD Detector model.

    • The Advanced GmAPD Detector Model now uses the same Mersenne Twister (MT) psuedo random number generator on all three platforms. This resolves the quantization issues on Windows when low dark count rates were combined with the stock 32-bit random number generator.

  • Demonstrations

    • New Demos

      • BumpMap2 is a second bump map example with imposed slopes that can be tested.

      • MixtureMap1 shows how to use a fraction cube to define multiple materials are a given location.

      • SubPixelObject1 shows how to enable hyper-sampling in pixels containing user-defined "important objects" that are very small.

    • DIRSIG5-Specific Demos

      • NormalMap1 shows how to incorporate a normal map to introduce variations in surface normals withing otherwise flat geometry.

      • ChipMaker1 utilizes a specialized combo-plugin to streamline the workflow of making large sets of image chips for training machine learning algorithms.

      • Caustics1 utilizes new scene plugins in the DIRSIG5 core to model water surfaces and sub-surface light propagation.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.7.3.17195

Release Date: Fri Apr 28 17:00:02 EDT 2017

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • General

    • Further updates related to the simple cloud model.

    • Added initialization output for the map-based temperature solver.

    • Fixed a logic issue that caused user-defined source contributions to be unnecessarily computed onto the Sun, Moon and Sky.

    • Improved the handling of material maps using "null" materials when mixing is enabled.

    • Sources can now be assigned simple "blinking" parameters (instant on/off at a user-defined frequency) (see the updated Sources4 demo).

  • LADAR/LIDAR

    • BPF3 formatted point cloud files can now be generated from the simple/basic LIDAR detector model.

    • Added the new crosstalk fill and scaling tools to the Advanced GmAPD Database Builder tool.

  • Important bug fixes (see the link below to view all the Resolved Issues)

    • Removed the debug output generated by user-defined sources that accidentally made it into the 4.7.2 final release.

    • Added a fix to catch inconsistent geometry with vertex plane normals that point in the opposite direction as vertex normals.

    • Fixed a problem with using the <basesource> mechanism in GLIST files.

    • User-defined source radiant intensity files are now correctly searched for in bundled geometry.

    • Fixed a bug where the view buttons in Bulldozer were not consistent with the default orientation expected by the scene motion models.

    • Fixed a bug with the simple/basic LIDAR detector model producing corrupt LAS point cloud files when using the Geiger-mode detector model.

    • Fixed a bug where a data-driven clock did not loop as expected.

    • Fixed a bug where a material defined in a material file as a material mapped proxy could would create an error about missing a temperature solver. Although the material shouldn’t need it and even if you added a temperature solver, the error would be generated.

  • Demonstrations

    • Improved Demos

      • The Sources1 demo was expanded to feature multiple point sources employing multiple geometry and radiometry descriptions.

      • The Sources4 demo was expanded to feature a pair of "blinking" sources.

    • New Demos

      • FastCloud1 shows how to bundle the simple cloud model in an object.

      • TemporalIntegration2 shows temporal integration blurring due to a moving platform.

      • RollingShutter1 shows blurring and artifacts in a moving object due to rolling shutter readout of a 2D array.

      • NestedMotion1 shows a hierarchy of various motion models in a single scene.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.7.2.16784

Release Date: Thu Sep 29 22:36:27 EDT 2016

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Fixed a series of bugs (#1, #2, #3 and #4) related to the simple cloud model.

  • Fixed a bug with the tracking mount correctly pointing at objects with instance offsets. In addition, the TrackingMount1 demo was improved to have two moving targets that can be tracked.

  • Fixed a bug with adjacent material mixing in materials maps.

  • Fixed a bug with solar and lunar ephemeris that resulted in using positions for the wrong day when the UTC hour offset rolled the day.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.7.1.16605

Release Date: Mon May 9 19:54:32 EDT 2016

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Changed the behavior of the attribution mechanism for OBJs via the GLIST file (see related bug).

  • Fixed a bug related to memory indexing uncovered by the OpenWater2 demo.

  • Fixed a bug with the Simple radiometry solver introducing specular effects on diffuse surfaces.

  • Fixed a bug related to material assignment issue surfaced by the RegularGrid1 demo.

  • Fixed a bug where the Scene Editor would inject spaces into material labels used in map assignments.

  • Fixed an issue with sumo2dirsig utility that would cause vehicles to "jump" related to limited precision in the SUMO network files.

  • Fixed a bug with using sub-object motion with objects that asymmetrically expand their bounding box.

  • Fixed a bug that resulted in mixture maps not working correctly.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.7.0.16452

Release Date: Thu Dec 3 21:22:19 EST 2015

This is a major release. The following features were introduced in the DIRSIG 4.7.0 release:

  • Features

    • Material labels (IDs) can now be alphanumeric, rather than strictly numeric.

      • Note that this feature may impact how some people have been attributing OBJ geometry files. Please see this bug for more information.

    • New GLIST features to enable geometry and material bundling (see the new BundledObject1 demo).

    • Improvements to details provided about the scene during load:

      • Improved output while the scene geometry and materials are loaded.

      • The new geometry_report.txt file captures the hierarchy of embedded geometry, automatically instanced geometry and material attribution.

      • The new material_report.txt file captures the mapping of global material indexes (the values captured in the updated material truth) to material labels (IDs), material names and the file the material was defined in.

    • Public release of the Advanced GmAPD Lidar toolchain.

      • A more advanced version of the Geiger-mode Avalanche Photo-diode (GmAPD) detection and point generation tool provided by the general LIDAR tool.

      • The advanced tools allow the user to provide per-pixel photon detection efficiency (PDE) and dark count rate (DCR) that are a function of operating conditions.

      • The advanced tools also allow the user to incorporate crosstalk (a feature not available in the general tool).

    • Simplified installation method for Mac OSX

      • Open the disk image and simply drag the DIRSIG4 folder into Applications or wherever you would like to install the software.

  • Important bug fixes (see the link below to view all the Resolved Issues)

    • The IDAY variable wasn’t always updated in the MODTRAN tape5 files, which would impact the Earth-Sun distance (the Sun position was correct). (External link)

    • Temporally correlated jitter values were not correctly captured in the data recorder instrument or in the LIDAR BIN file. This made it impossible to achieve ideal reconstructions of 2D or 3D imagery. (External link)

    • Atmospheric backscatter returns in LIDAR simulations were not being computed in the 4.6.x release cycle. (External link)

  • Documentation

  • Demonstrations

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.6

DIRSIG 4.6.3.15676

Release Date: Thu Jul 17 00:18:15 EDT 2015

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • An artifact (unreasonable values and gradients) in the path radiance would manifest itself across the field-of-view for exo-atmospheric instruments looking at the Earth.

  • A variety of issues related to enabling temporal oversampling of the range gate for a LIDAR sensor were resolved.

  • The ability to enable and disable various maps in the scene file via the Scene Editor was improved.

  • The issue with the progress bar not always reaching 100% when a simulation completed was resolved.

  • Temporal oversampling can now be combined with a data-driven focal plane.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.6.2.15518

Release Date: Sun May 3 18:31:51 EDT 2015

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Fixed some missing date/time stamps on probe rays used by the built-in THERM temperature solver. This would result in aborts for thermal simulations. This update also fixed a previous undiscovered bug that resulted in thermal shadows not responding to dynamic geometry.

  • Added the new Thermal2 demo to exercise how object temperatures respond to moving objects and the shadows created by them.

  • Fixed a bug related to user-defined sources that would disappear when their pointing direction was not axis-aligned.

  • Restored some methods that allowed the user to generate thermal emission when using the data-driven temperature solver without needing to trigger all thermal calculations.

  • Improved the parsing of large GLIST files, which in some cases didn’t release a large amount of memory after the XML file was parsed.

  • Fixed an issue that caused preview mode for LIDAR simulations to have no active return flux in the output BIN files.

  • Improved the parsing of DeltaMotion MOV files to address negative and zero delta time steps.

  • Fixed some initialization issues when using old DIRSIG3 era simulation descriptions.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.6.1.15063

Release Date: Tue Dec 16 15:49:20 EST 2014

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Fixed a place where rays were not being assigned valid date/time stamps. As a result, this caused scenes with any dynamic content to have artifacts or even crash (External link and External link).

  • Fixed a poor spectral bandpass and channel setup in the Polarization2 demo.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.6.0.14842

Release Date: Fri Nov 7 12:20:17 EST 2014

This is a major release. The following features were introduced in the DIRSIG 4.6.0 release:

  • New resume mode

    • A way to resume a DIRSIG simulation that stopped during a previous run.

      • Only available for the passive "simple" and "raw" capture methods at this time.

    • You can learn more about this feature in the DIRSIG command-line guide.

  • General optimizations

    • Faster geometry loading and sorting

    • Faster radiometry calculations

    • Added r-tree sorting to both static and dynamic (moving) user-defined sources, which results in nearly constant time simulations regardless of the number of sources in the scene.

  • Improved suite of "simple" radiometry tools

    • The new Simple radiometry solver

      • The new radiometry solver is much faster than the the Generic radiometry solver and much better than the Classic radiometry solver.

      • This new solver is now featured in many of the distributed demos and is the recommended solver for all new scene construction.

    • New and improved "simple" optical properties (basic 2-column data)

      • SimpleReflectance (ASCII/Text and XML input) for surface reflectance.

      • SimpleTransmission (ASCII/Text and XML input) for surface transmission.

      • SimpleAbsorption (ASCII/Text and XML input) for volume absorption.

      • SimpleScattering (ASCII/Text and XML input) for volume scattering.

  • Improvements to the adaptive sampling algorithm to minimize temporal differences in pixels with both static and dynamic content.

  • Improved version of the Ross-Li BRDF model, which now supports the "thick" vs. "thin" and "sparse" vs. "dense" formulations.

  • New units options for radiance image produced by the Basic capture method

    • Selectable area units (per m2 or per cm2)

    • Selectable flux units (watts, milliwatts, microwatts or photons/second)

  • New object instancing tools

    • Various automated object instancing tools in the GLIST file help users procedurally fill scenes with objects (see the DensityMap1 and PolyFill1 demos for more information).

    • "Decal maps" simplify the placement of objects on top of other objects (see the DecalMap1 demo for more information).

  • The initial version of Flexible motion model is officially "done" at this time.

    • This module includes tools for defining both scene (object) and platform motion. There are tools to directly use an SGP4 propagator with a two-line element (TLE), data-driven support for quaternions, and more.

    • See the Flexible Motion model guide for options, use cases and examples.

    • See the FlexMotion1 demo for more information on using it for scene content.

  • New instance truth and track extraction tool

  • New data-driven temperature solver

    • A new temperature solver we added that allows the user to specify the temperature as a function of time (see the new DataDrivenTempSolver1 demo for more information).

  • New modulating user-defined source option

    • Added support for modulating sources (see the Sources4 demo for more information).

  • New exo-atmospheric source positioning options

    • Ability to specify a fixed Sun location (zenith and azimuth) is available in the new Ephemeris tab on the Atmospheric Conditions Editor.

    • New scriptable sun location model lets users specify the location of the sun via a script (requires manual editing of the .atm file at this time).

  • Improved radar modality features (this modality is still experimental)

    • Materials properties are no longer embedded in the .platform file. The new SarReflectivity optical property model can be used via the material database file.

    • The required .platform variables have been distilled down to a minimum. The applicable section of the Radar Modality Handbook has been updated to describe the improvements.

  • Improvements to psuedo random number generation

    • Added a new command-line option to specify the global random seed.

    • Added some options to override the seed for specific random number generators associated with specific components.

  • Packaged data sets

    • Added "standard" relative spectral response (RSR) files for Si (Silicon), InSb (Indium Antimonide), and HgCdTe (Mercury Cadmium Telluride) sensors.

  • Scene Updates

    • Foxbat scene

      • Added water tower near the fuel storage area.

      • Added floodlights around the perimeter of the aircraft movement area.

    • Warehouse scene

      • Added floodlights to the rear storage yard.

  • New Documentation

  • Demonstrations

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.5

The following important changes were made in the DIRSIG 4.5.x releases that will result in different output when compared to simulations from previous releases (for example, DIRSIG 4.4.4 and older releases):

  • A "Setup Wizard" will start the first time you launch the user interface. It will guide you through a basic configuration process, including MODTRAN configuration. This wizard will only run the first time you launch the user interface with DIRSIG 4.5.

  • In previous releases, the UV projection scheme was automatically used if the source geometry included UV coordinates (for example, an OBJ file containing "vt" coordinates). In this release, those objects will not automatically switch from the "drape" projection scheme in the .scene file to the "UV" projection scheme. The user must explicitly select the "UV" projection scheme, otherwise the "drape" scheme in the .scene file will be honored.

  • In previous releases of DIRSIG, an unpolarized reflectance model (for example, the "Classic Emissivity", "Ward", "Phong", etc. models) would "preserve" polarization. Radiometrically, this behavior was deemed a poor approach and in DIRSIG 4.5 and later these optical properties will be 100% depolarizing.

  • The format of the ASCII/Text point cloud files has changed slightly. Please consult the Lidar Modality Handbook for more information.

  • Several significant change were made to user-defined (secondary) sources in the 4.5.1 release. Details about this feature and some of these changes are discussed in the User-Defined Sources Manual.

    • A bug (External link) in the code was fixed that had these sources producing radiances with the wrong units (they were off by a factor of 10,000 because of a m2 vs. cm2 factor). If users figured this out on their own and had adjusted their input INT files to compensate, then those users will will need to revert their files back to the correct units.

    • The default value for the NORMALIZE_SHAPE option was changed to TRUE. This means that older scene setups using sources that didn’t have this option specified will behave differently with 4.5.1 and all releases going forward.

Release 4.5.4.13875

Release Date: Thu May 22 22:13:34 EDT 2014

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Important bug fixes (see the link below to view all the Resolved Issues)

    • Material truth did not report the fraction for mixed materials correctly (External link).

    • Simulation progress bar did not complete as expected (External link).

    • Sign of whisk mount angles was backwards (External link).

    • Flexible motion "LookAt" orientation engine was not initialized correctly (External link).

    • Independent clock offset was not written out (External link).

    • Image file format plugins were not included on Windows (External link).

  • New features

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

Release 4.5.3.13312

Release Date: Wed Jan 2 14:05:37 EST 2014

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Important bug fixes (see the link below to view all the Resolved Issues)

    • Matlab BIN file reader did not account for time bin width (External link).

    • Task Editor crashes upon saving a new set of tasks (External link).

    • File write errors did not result in fatal error (External link).

    • Image viewer tried to automatically load images with wrong path (External link).

  • New features

    • Basic progress bar for multiple capture simulations (for example, multiple array readouts in a pushbroom collection, video collection, LIDAR collection, etc.).

    • Graphical interface support for user-defined LIDAR temporal pulse profiles was added.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

Release 4.5.2.13188

Release Date: Mon Nov 11 20:43:10 EST 2013

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Important bug fixes (see the link below to view all the Resolved Issues)

    • Memory leak when using adaptive sampling with multiple captures (frames) (External link).

    • Fixed lost geolocation info in the ENVI header for "file per capture" output schedules (External link).

    • Updated Blender plugins now work with Blender 2.4x, 2.5x and 2.6x (External link).

    • Supplied MATLAB LIDAR BIN file reading code now works with files produced since DIRSIG 4.5.x. (External link).

  • New features

    • Added a "split" tool to the Simulation Editor, which allows the user to split some simulations into multiple smaller simulations so the user can achieve pseudo parallel processing.

    • Added support for the UTM reference frame for platform orientation angles.

    • Added the option to specify a time offset for independent clocks (previously only slaved clocks could have offsets).

  • New documentation

  • New demonstrations

    • LeafStack1 (example of "leaf stacking effect" and Leaf Area Index (LAI) truth collector).

    • LidarPointing1 (shows command errors (jitter) and knowledge error impacts on 3D point clouds).

    • LidarUserPulse1 (shows how to import an user-defined temporal pulse profile).

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

Release 4.5.1.12800

Release Date: Fri Aug 9 06:02:02 EDT 2013

This release is primarily a maintenance release, which is focused on bug fixes and the addition of only minor new features.

  • Important bug fixes (see the link below to view all the Resolved Issues)

    • Multiple changes and fixes with respect to user-defined sources (External link, External link and External link).

    • Integrated channel values were always unpolarized, even when a a polarized radiance was predicted and a polarization filter was applied (External link).

    • Problems with make_adb under Windows when the MODTRAN path contained spaces (External link).

    • Adaptive sampling parameters were not reloaded into the user interface correctly for LIDAR receiver focal planes (External link).

    • Viewing a weather file would erase the weather file path from the Atmospheric Conditions Editor (External link).

    • Truth image file only contained the last capture regardless of the output file schedule (External link).

    • Temporally uncorrelated jitter was not working (External link).

    • Temporally correlated jitter editor needed lots of improvements (External link).

    • The unit tester would crash at the end under Windows (External link).

    • Trees in the Forest and Urban scene do not show up in LIDAR simulations (External link).

  • New features

    • New "Leaf Area Index" truth collector.

    • Access to the "normalize shape" option for sources in the Material Database Editor.

  • New/Improved demonstrations

    • The "Sources1" demo was improved to include a realistic point source.

  • New/Improved documentation

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

Release 4.5.0.12124

Release Date: Fri Feb 22 10:16:07 EST 2013

Summary of new features:

  • Performance improvements

    • New spectral library code greatly improves many spectral and/or polarimetric simulations:

      • On average, most simulations are now 2x faster.

      • An AVIRIS-type simulation is now 6x faster on the Foxbat scene

      • Most polarized simulations are now running 2x - 5x faster.

      • Most LIDAR simulations are 2x - 3x faster.

    • Improved geometry and motion support greatly improves scenes with lots of static and moving geometry:

      • A simulation containing a large number of moving items is 6x faster.

  • LIDAR improvements

    • Created the new LIDAR modality handbook.

    • Added the ability to define fixed or dynamically polarized transmitter and receiver components.

    • Added the ability to have more than 1 receiver focal plane array (FPA).

    • Improved "spatial response" options for LIDAR FPAs.

    • LIDAR detector model enhancements

      • Added new "photon counting" detection model which emulates the ATLAS sensor on the forthcoming ICESat-2 satellite.

      • Addition of LAS 1.3 output option for point cloud files, which can be directly loaded by several free point cloud visualization tools.

      • Improvements to ASCII/Text output option for point cloud files, including support for different geolocated coordinate systems.

  • Improved documentation

  • Truth image improvements

    • Added support for output file schedule options.

    • Added the new "abundance" truth, which allows the user to create image planes that contain the fraction of a user-defined set of materials that are contained in each pixel (one band per supplied material ID).

  • Run-time options

    • Ability to specify an output folder and file prefix when you start a simulation (improves ability to reuse .platform files).

    • Improved command-line options and syntax for both dirsig and make_adb.

  • Scene property map improvements

    • Added ability to use PNG, JPEG and GIF file formats (in addition to PGM) for most property maps.

    • Added the explicit UV map projector.

    • Added property map features to support different image origin conventions, flip vs. mirror options, etc.

  • Different image data scaling options available within the built-in image viewer tool.

  • Simplified installation and user specific settings

    • Eliminated the DIRSIG_HOME environment variable.

    • MODTRAN configuration is now stored in the users settings (no longer lost with each update) and users can configure more than one MODTRAN setup to use.

    • Windows users can now "double-click to open" most component files if they manually setup the default program for those files to be the DIRSIG editor.

    • The "visual preview" tool has been merged with the main DIRSIG editor.

  • Improved the command-line "object tool" program

    • Added significant options to manipulate and convert object geometry.

  • New Demonstrations

    • CommandedMount1 (direct command platform-relative pointing)

    • DataDriven1 (data-driven focal plane with linear and non-linear gain models)

    • ExternalTriggers1 (driving a clock with external, irregular trigger times)

    • ScriptedMount1 (platform-relative pointing via user-supplied script)

    • TabulatedMount1 (platform-relative pointing vis user-supplied data)

  • Important bugs

    • Scriptable mount is working.

    • External clock trigger mechanism is working.

Known Issues (External link to Bugzilla)

Resolved Issues (External link to Bugzilla)

DIRSIG 4.4

Release 4.4.4.11164

Release Date: Wed Aug 29 09:33:56 EDT 2012

This release is primarily a maintenance release. Here is a general list of the new features and improvements appearing in this release:

  • Updated reference documentation

  • Fixed temperature truth generation

  • Fixed global to local polarization rotations

  • Fixed INCLUDE_FILE mechanism for material database files

  • Improved functional and user-define channel response integration

  • Improved PGM header support

  • Improved support for truth file output schedules

  • New GUI weather generation tool

  • New GUI for advanced options

  • New data-driven focal plane demo with non-linear gain

Resolved Issues (External link to Bugzilla)

Release 4.4.3.10639

Release Date: Sun May 13 23:19:33 EDT 2012

This release is primarily a maintenance release. Here is a general list of the new features and improvements appearing in this release:

  • New reference documentation

  • Fix to default GLIST and ODB rotation order

  • Support for viewing exo-atmospheric objects with "Simple" and "Threshold" atmosphere models

  • Improved support for defining spectral bandpasses in nanometers

  • Improved speed when loading large ODB files

  • Improved spotlight collection wizard

  • New/Updated LIDAR demonstrations

    • LidarBounces1

    • LidarDynamicGate1

  • New/Updated RADAR demonstrations

    • SpotlightSar1

    • StripmapSar1

    • QuadPolSar1

Related Issues (External link to Bugzilla)

Release 4.4.2.9954

Release Date: Sun Jan 15 22:15:58 EST 2012

This release is primarily a maintenance release. Here is a general list of the new features and improvements appearing in this release:

  • Significant performance improvements to LIDAR simulations (~20x faster)

  • Adaptive sampling support in the Graphical User Interface (GUI)

  • Data-drive focal plane support in the Graphical User Interface (GUI)

  • Improvements to graphical "Simulation Preview" tool

  • New extended-area, directly viewable sources

  • New "Refinery" scene

  • 10 new demonstrations

    • Bayer pattern focal plane (BayerPattern1)

    • Expanded BRDF examples (Brdf1)

    • LIDAR returns from sub-pixel structures (LidarEdge1)

    • LIDAR returns from a sloped surface (LidarSlope1)

    • A geo-synchronous, exo-atmospheric "moon-like" satellite (MoonSat1)

    • A 4-camera, division-of-aperture polarization system (Polarization4)

    • A 2x2 microgrid division-of-array (focal plane) polarization system (Polarization5)

    • Expanded primitive geometry objects (PrimitiveObjects2)

    • An extended-area, directly viewable source (Sources2)

    • An advanced UV mapping example (UvMapping2)

  • Bug fixes related to using the "Classic" atmosphere model

    • Improved compatibility with MODTRAN5 2.0.0

    • Issues with platforms on space based platforms

    • Issues with platforms on the ground looking at exo-atmospheric objects

  • Scene Editor upgrades

    • New "General" tab with preview image

    • Option for implicit scene "base directory" using the location of the .scene file

    • More meta-data than just the scene "name"

  • Platform Editor upgrades

    • New tabbed layout of the focal plane editor

    • Improved data-driven detector array geometry support

Resolved Issues (External link to Bugzilla)

Release 4.4.1.8286

Release Date: Thu Mar 10 10:19:01 EST 2011

This release is primarily a maintenance release. Here is a general list of the new features and improvements appearing in this release:

  • First release to include a Windows 64-bit version

  • Improvements to correlated deviate models used for jitter

    • The frequency spectrum can now (optionally) include the phase

  • New demonstrations

    • Indoors1

    • ExtinctionProps1

  • Blender plug-ins for DIRSIG file formats

  • Various LIDAR related improvements

    • Speedups for atmospheric backscatter returns

    • Bug fix for Linear-mode APD LIDAR detector model

  • Various GUI bug fixes and improvements

  • Improvements to streamline integration with SUMO and CityEngine

    • SUMO vehicle track import utility included on all platforms

  • Simplified shared library requirements for Solaris

  • Initial MuSES support built-in for the following platforms

    • Windows 32-bit

    • Windows 64-bit

Resolved Issues (External link to Bugzilla)

Release 4.4.0.7420

Release Date: Fri Oct 15 09:28:51 EDT 2010

Summary of new features:

  • New User Interface Tools

    • Graphical simulation preview

    • Basic image viewer

    • Component browser

    • SGP4 Orbiting Platform Motion Wizard

  • Geometry Improvements

    • Added affine transform INFO option to ODB

    • Ray-trace optimization for dynamic (moving) scene geometry

    • Support for vertex normals (normal "shading") on OBJ input geometry

  • Atmosphere

    • Added the GUI for the UniformAtm model

    • User-defined MODTRAN profile support (make_adb config file) in GUI for ClassicAtm and ThresholdAtm models

    • ClassicAtm reuse ADB check in GUI runs

  • Other

    • General performance improvements

    • Flight data recorder instrument

    • Improved demos (most upgraded to SIM and new HTML index)

    • New "warehouse" scene

Resolved Issues (External link to Bugzilla)