Instantly Remove Pesky Salt-and-Pepper Noise

Are bright and dark pixels/lines ruining the visualization and analysis of your image? Then use the Hot & Cold Pixel Remover, included for free in the Huygens Software! Leverage an efficient algorithm to find and correct hot and cold pixels.

• Boost visual contrast by removing intense spots and streaks.
• Clean up your image before deconvolution, negating detector artifacts.
• Massively increase the reliability, and accuracy of colocalization analyses.

Huygens Hot & Cold Pixel Remover—located under the Deconvolution & Restoration menu—automatically finds hot or cold pixels across the Z-axis, timeseries and channels. Rapid visualization is facilitated with familiar controls, and the sensitivity for outlier pixels can be easily adjusted and reviewed with a simple slider. Export or import masks for quick and consistent corrections. Stay quantitative by providing the mask with your data in the workflow processor for batch-processing.

Huygens already uses sensible defaults. Just check the settings per channel or timeframe, and export your image or mask if the result looks good!

Visualization: Twin slicer settings are incorporated in the tool for visualization. These settings are found under View options. You can specify whether to look for and remove hot and/or cold pixels by clicking the blue bars at the top, or the tickboxes at the bottom right. Since Huygens 25.10, both can be corrected in one go! Just below, there is an option to visualize the correction with an ROI instead of the full image, which can be faster in large images. You can also overlay the mask of hot / cold pixel locations on the image.

Sensitivity: Huygens estimates the sensitivity for hot and cold pixels, however, it can be fine-tuned for each channel using the slider. Higher sensitivity increases the odds of false positives, while a lower sensitivity may not remove all out-liers. Ideally, lower the sensitivity as much as possible without hot / cold pixels showing.

Axial correlations: If you are not sure if any exist, you can simply disable them. This option is relevant when a defect detector causes hot / cold pixels. (hidden if not applicable for dataset)
Correlation along Z: Due to camera defects, certain pixels in the 2D sensor grid can have irregular high / low outputs. When the image is recorded slice-by-slice, each Z slice subsequently has a high likelihood of having a hot / cold pixel at that same location. This leads to “hot and cold columns”, which show up as vertical lines in XZ and YZ like a barcode. As this is the most common case, along Z is true by default.
Correlation along Channels: In multi-channel images, if the same faulty detector is used per channel, the correlation option should be enabled.

Masks: The corrector tool has both import and export for masks. These can be used in repeated workflows with the same microscope.