Stray light (flare) documentation pages
Introduction: Intro to stray light testing and normalized stray light | Outputs from Imatest stray light analysis | History
Background: Examples of stray light | Root Causes | Test overview | Test factors | Test Considerations | Glossary
Calculations: Metric image | Normalization methods | Light source mask methods | Summary Metrics | Analysis Channels | Saturation
Instructions: High-level Imatest analysis instructions (Master and IT) | Computing normalized stray light with Imatest | Motorized Gimbal instructions
Settings: Settings list and INI keys/values | Standards and Recommendations | Configuration file input
25.2
Calculations
- Adds the ability to downsample the analysis image(s)
Normalization
- Direct Reference Image: Adds the ability to average the normalization factor from multiple reference images
- Lambertian Reference Image: Adds the ability to average the normalization factor from multiple reference images
Masking/Source Detection
- Adds the ability to save/view diagnostic plots from the masking/source detection
- Adds the ability to use a geometric calibration model (simple pinhole or OpenCV) + circle to mask the analysis images
- Adds the ability to manually place a circle for the reference image(s)
Settings
- Adds the ability to select a colormap for the color-mapped metric image output
- Adds the ability to invert the colormap for the color-mapped metric image output
- Adds the option to toggle the pink mask overlay in the color-mapped metric image output
- Updates INI syntax (breaking change)
Miscellaneous
- Significantly improved the speed of video/frame writing (associated with the color-mapped metric image and histogram outputs)
- Improved the visual appearance and rendering consistency of color-mapped metric image and histogram outputs
25.1
Metadata Attribution
- Adds the ability to extract angle metadata from a filename via regular expression
Masking/Source Detection
- Adds the ability to compute a mask radius via focal length ratios
- Adds the ability to select the smallest of multiple connected components
Calculations
- Adds the ability to select custom weights for a luminance channel
Results
- Adds XML as a result type
- Makes use of a new results-generation engine, which generates documentation of results
Nomenclature
- Renames “Masking” to “Source Detection” for the reference image
24.2
Usability
- Adds a “low-memory” mode
- Makes use of the new batch folder processing from the main window
Calculations
- Adds the ability to analyze the median channel
Results
- Adds an indication of the exit condition for image processing masking to the result file(s)
Settings
- (Imatest Master Only) Reorganizes the settings GUI and adds indications of bad settings at save time
- Updates INI syntax (breaking change)
Plotting
- Adds the ability to set the y-axis upper bound of histogram plots/videos
Deprecations
- Removed support for saving plots as some image formats image formats
24.1
Calculations
- Adds the ability to compute ITU-R BT.709-6, ITU-R BT.2020-2, and MATLAB luminances
- Adds saturated pixel counts per analysis image
- Adds maximum measurable stray light calculation
Settings Interface
- (Imatest Master Only) Hides plot, image, and video settings that are not used based on upstream settings
Future Changes
- Some line plot image formats will be removed in future releases
23.2
Standards
- Adds support for IEEE-P2020 Pre-Release Flare Attenuation
Normalization
- Adds Lambertian Diffuser Normalization for IEEE-P2020 Pre-Release Flare Attenuation
Calculations
- Adds the ability to select the analysis channel(s)
- Adds the ability to select a transformation (log, dB, etc.) of the stray light data
- Adds the ability to subtract off a dark level
- Adds the minimum measurable stray light to the result files
- Adds the ability to express count plots/metrics in terms of percent of pixels
- Adds improved visual separation of masked pixels in color-mapped metric images
Nomenclature
- Renames “Reference Image” Normalization to “Direct Reference Image“
- Renames “Two Pass Circle Radius” Masking to “Image Processing + Circle (Radius)“
Miscellaneous
- Adds the ability to reload settings from the INI
Future Changes
- Some line plot image formats will be removed in future releases
23.1
Masking/Detection
- Separates masking settings for the reference image and test images
- Adds the ability to use the Image Processing masking method
- Adds the ability to use no masking (test images only)
- Adds a minimum stray light level threshold to Image Processing-based source masking to improve masking when the source is out of the FOV
- Adds the ability to use Otsu’s method to determine the light source threshold for Image Processing masking
Normalization
- Adds normalization with the user-provided level
- Adds integration time, light level, and gain compensation factors for the Reference Image normalization
Analysis
- Adds count results: number of pixels with stray light worse than user-provided thresholds
Nomenclature
- Renames “On-Axis” normalization to “Reference Image“
- Renames calculation methods:
- Normal → Transmission
- Reciprocal → Attenuation
Results
- Adds tabs (extra commas) in CSV outputs to delineate sections
22.2
- Initial stray light offering