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Diameter Analysis

Diameter analysis estimates vessel diameter from line scan kymographs.

The analysis operates on intensity profiles derived from a selected ROI and produces diameter summaries, per-row or per-window results, and quality-control values.

Input data

Diameter analysis expects image data organized as a line scan kymograph. The ROI should cover the spatial region used to estimate vessel diameter.

Detection parameters

Detection parameters define the scientific behavior of the analysis. Diameter analysis parameters control profile aggregation, polarity, thresholding, gradient-based edge detection, motion gating, and post-filtering.

Diameter Detection Parameters

name display_name type default choices unit editable visible methods description
window_rows_odd Window Rows (Odd) int 5 True True ('threshold_width', 'gradient_edges') Odd number of time rows aggregated into each spatial profile.
stride Stride int 1 True True ('threshold_width', 'gradient_edges') Center-row increment between successive measurements.
binning_method Binning Method enum mean ('mean', 'median') True True ('threshold_width', 'gradient_edges') Window reducer across rows before edge detection.
polarity Polarity enum bright_on_dark ('bright_on_dark', 'dark_on_bright') True True ('threshold_width', 'gradient_edges') Intensity polarity; dark_on_bright inverts the profile.
diameter_method Detection Method enum threshold_width ('threshold_width', 'gradient_edges') True True Core detector implementation.
post_filter_kernel_size Post-Filter Kernel Size int 3 True True Odd median kernel applied to diameter after detection. Post-detection smoothing; re-run analysis to apply changes.
threshold_mode Threshold Mode enum half_max ('half_max', 'absolute') True True ('threshold_width',) Threshold rule for threshold_width.
threshold_value Threshold Value float 0.0 True True ('threshold_width',) Absolute threshold when threshold_mode='absolute'.
gradient_sigma Gradient Sigma float 1.5 True True ('gradient_edges',) Gaussian smoothing sigma for gradient edge finding.
gradient_kernel Gradient Kernel enum central_diff ('central_diff',) True True ('gradient_edges',) Derivative kernel for gradient_edges.
gradient_min_edge_strength Min Edge Strength float 0.02 True True ('gradient_edges',) Minimum derivative magnitude for a confident edge.
enable_motion_gating Enable Motion Gating bool True True True ('gradient_edges',) Apply frame-to-frame motion constraints for gradient_edges.
max_edge_shift_um Max Edge Shift (um) float 2.0 True True ('gradient_edges',) Maximum allowed per-frame left/right edge shift.
max_diameter_change_um Max Diameter Change (um) float 2.0 True True ('gradient_edges',) Maximum allowed per-frame diameter jump.
max_center_shift_um Max Center Shift (um) float 2.0 True True ('gradient_edges',) Maximum allowed per-frame center shift.

Results

Diameter analysis stores summary values in the AcqImage JSON sidecar and writes tabular output to a CSV file.

For a source file named my_file.tif, diameter analysis saves:

my_file.tif.json
my_file.tif.diameter.csv

The JSON sidecar includes the detection parameters and summary values for each analyzed ROI. Typical summary values include:

  • diameter_um_mean
  • diameter_um_median
  • diameter_um_cv
  • num_rows
  • qc_score_mean
  • quality-control violation counts

The CSV file stores tabular diameter results.

Programmatic use

Diameter analysis can be run from the GUI or from Python code using the same acqstore backend.

See the Diameter Analysis API.