Understanding Dynamic Inverse Simulations

The following page presents you what is a dynamic Inverse simulation and its capabilities.

A dynamic Inverse simulation allows a Camera sensor to capture dynamic scenes with related effects such as rolling shutter, motion blur, or LED flickering.

The principle of a dynamic inverse simulation is the consideration of the time. For moving objects, each given position of an object is defined in function of a given time. For flickering sources, each relative flux variation of a source is defined in function of a given time.

Tool Set

Inverse simulation: the Inverse simulation will determine the start time of the timeline.

Note: Dynamic Inverse simulations are only compatible with the Monte-Carlo algorithm.

Camera sensor: the Camera sensor is the mandatory element to capture the different dynamic effects.

Speos Light Box: the Speos Light Box is a container of objects that can move in function of the time if a Trajectory file is set.

Surface source: the Surface source can flicker during the simulation if a Flux variation file is set.

Important Parameters

Note: For more information on each parameter, click the related link.

Integration (Camera Sensor): corresponds to the time needed to get the data acquired by one row of pixels.

Lag time (Camera Sensor): corresponds to the time difference between two rows of pixels to start the integration.

Trajectory File (Camera Sensor, Speos Light Box): *.json file defines the position and orientations of an object in time.

Timeline (Inverse Simulation): allows the Inverse simulation to consider the time.

Start time (Inverse Simulation): determines when the timeline-related parameters are taken into account in the simulation.

Flux Variation File (Surface Source): *.json file that defines the samples for one period representing the variation of the relative flux of the source with time.

Relative Lag (Surface Source): represents the relative time along the period when the source starts to emit light. That means the relative lag includes a temporal shift of the time period.

Capabilities

Note: The following list is non-exhaustive. This only presents you some basics to describe you how to manage dynamic elements.

With a dynamic Inverse simulation, different scenarios are possible:

You can create a simulation of a moving Camera sensor
You can create a simulation of a moving Speos Light Box
You can create a simulation of a Surface source with a flickering effect
You can create a simulation of a moving Surface source with a flickering effect

The Inverse simulation then generates a spectral exposure map (*.xmp) for each sensor, even the static sensors. This map corresponds to the acquisition of the Camera sensor and expresses the data for each pixel in Joules/m²/nm.

Note: As of version 2024 R2, the Trajectory file is no longer necessary to consider an Inverse simulation as dynamic, according to the scenario.