Electro-optical imaging systems: Performance measurement

Electro-optical imaging system performance measurement

The minimum resolvable temperature difference (MRTD), the minimum resolvable contrast (MRC), and the triangle orientation discrimination (TOD) are end-to-end EO system performance measures; that is, laboratory measures that characterize EO system performance with a human observer in the loop. Such system performance measures are used: 1) to...

Baxster: an image quality tester for x-ray baggage screening systems

TNO Human Factors in the Netherlands developed a prototype apparatus for testing the image quality of X-ray Baggage Screening Systems: BAXSTER. BAXSTER stands for BAggage X-ray Screening TesteR. The test has a variety of applications, e.g. support by the choice of optimal screening systems for airport security, comparison of competing X-ray...

Human search with a limited Field of View: the effect of scanning parameters and scene content

In order to find an optimal scanning strategy we determined the relationship between search performance and several scanning- and scene parameters in human observer experiments. The observers searched with a limited field of view (FOV) through a large search sector for a target (a camouflaged person) on a heath. From trial to trial the target...

TOD, NVTherm and TRM3 model calculations: a comparison

At the moment there are three potential models and associated measures to replace the FLIR92 model and the MRTD as the standard for sensor performance characterization and TA range predictions. These are: 1) the NVTherm model that calculates the MRTD-ID, 2) the TRM3 model that calculates the MTDP and 3) the TOD model that calculates the TOD. The...

Image dataset for testing search and detection models

The TNO Human Factors Searchû2 image dataset consists of: a set of 44 high-resolution digital color images of different complex natural scenes, the ground truth corresponding to each of these scenes, and the results of psychophysical experiments on each of these images. The images in the Searchû2 dataset are a subset of a larger set that has...

Capturing the sampling effects: A TOD sensor performance model

The standard way to characterize sensor performance is by means of the Minimum Resolvable Temperature Difference (MRTD) and Minimum Resolvable Contrast (MRC) methods. These methods are based on Fourier analysis and work reasonably well for linear (analogue) systems. However, nonlinear effects, such as sampling, are not properly accounted for. As...

A critical evaluation of test patterns for EO system performance characterization

The traditional test pattern for end-to-end EO system performance testing in the laboratory has been the static 3- or 4-bar target. This choice was governed by linear systems approach. The introduction of under-sampled imagers such as IRFPAs (infrared focal plane array cameras) has challenged the testing community to develop an alternative test,...

Automatic Characterization of Electro-Optical Sensors with Image Processing, using the Triangle Orientation Discrimination (TOD) Method

The objective characterization of electro-optical sensors and that of image enhancement techniques has always been a difficult task. Up to now the sensor is characterized using the minimum resolvable temperature difference (MRTD) or the minimum resolvable contrast (MRC). The performance of image enhancement techniques is done by visual...

TOD Predicts Target Acquisition Performance for Staring and Scanning Thermal Imagers

Identification and recognition performance for four staring and two scanning thermal imagers, were measured in an observer experiment using images that were collected during a NATO field trial in Nettuno, Italy, in 1998. The dataset allows validation of the MRTD and alternative sensor performance measures such as the TOD (Triangle Orientation...

T-CAT, Thermal camera aquity tester

Bias-free procedure for the measurement of the minimum resolvable temperature difference and minimum resolvable contrast

MRTD (Minimum Resolvable Temperature Difference) The characterization of electro-optical system performance by means of the standard minimum resolvable temperature difference (MRTD) or the minimum resolvable contrast (MRC) has a number of serious disadvantages. One of the problems is that they depend on the subjective decision criterion of the...

The triangle orientation discrimination test (TOD): A new alternative for MRTD and MRC

The current standard to characterize Electro-Optical system performance is the MRTD (Minimum Resolvable Temperature Difference) for thermal imagers and the MRC (Minimum Resolvable Contrast) for visual devices. This standard has at least three serious disadvantages: (i) the standard 4-bar test pattern is theoretically and practically unsuitable...

Triangle orientation discrimination: The alternative to minimum resolvable temperature difference and minimum resolvable contrast

The characterization of electro-eptical system performance by means of the minimum resolvable temperature difference (MRTD) or minimum resolvable contrast (MRC) has at least three serious disadvantages: (1) the bar pattern stimulus is theoretically and practically unsuitable for 1-D or 2-D spatially sampled systems such as pixel-array cameras, ...

Target acquisition: Human observer performance studies and TARGAC model validation (Final Report)

Human target acquisition performance was studied using the thermal imagery that was collected during Battlefield Emissives Sources Trials under the European Theater Weather and Obscurants, (BEST TWO), organized by NATO AC243/Panel4/RSG.l5 in 1990. Recognition and identification probabilities were measured for a large number of stationary and...

Photoreceptor light adaptation models: an evaluation

Two current descriptions of photoreceptor responses in the presense of adapting background illumination are evaluated. Both descriptions are based on the Michaelis-Menten equation V/V(m) = I(n)/(I(n) + ??(n)), but they use this equation in different ways: (1) to describe increment responses to light increments on a background (the 'increment ...

Transient tritanopia at the level of the ERG b-wave

A blue stimulus that is just visible in the presence of a yellow adapting field remains invisible for several seconds after the yellow field has been turned off. This 'transient tritanopia' is shown to exist already at the level of the b-wave of the electroretinogram. The experiments were done on rhesus monkeys and the results were qualitatively...