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Graph Abstraction for Simplified Proofreading of Slice-based Volume Segmentation. Ronell Sicat 1 , Markus Hadwiger 1 , Niloy Mitra 1,2. 1 King Abdullah University of Science and Technology 2 University College London. Motivation.
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Graph Abstraction for Simplified Proofreading of Slice-based Volume Segmentation Ronell Sicat1, Markus Hadwiger1, Niloy Mitra1,2 1 King Abdullah University of Science and Technology 2 University College London
Motivation • Extract 3D structures from electron microscopy (EM) data for analysis • Target application: Connectomics segmentation proofreading analysis input
Input • EM scans of mouse cortex (1024 x 1024 x 150 slices )
Segmentation • Automatic segmentation extracts neural structures (not perfect)
Proofreading • Search for and correct segmentation errors
Analysis • Segmented 3D structures are visualized and analyzed
Motivation • Proofreading – tedious and time consuming • We want abstraction of segmentation data • cheap to compute • provides search and correction support
Graph Abstraction of Segmentation Data • Node • segmented region • center of mass • Edge • connected regions (same object)
Inconsistency Weight node distance
Inconsistency Weight node distance
Inconsistency Weight node distance region overlap
Inconsistency Weight node distance region overlap
Inconsistency Weight node distance region overlap
Inconsistency Weight node distance region overlap
Automatic Correction for Special Case Errors • Fixing extensions • average bounding box is used for clipping • more complex bounding region can be used before
Automatic Correction for Special Case Errors • Fixing extensions • average bounding box is used for clipping • more complex bounding region can be used before
Automatic Correction for Special Case Errors • Fixing extensions • average bounding box is used for clipping • more complex bounding region can be used after
Automatic Correction for Special Case Errors • Fixing holes • fill hole if present in both neighbor regions • more sophisticated methods can be used before
Automatic Correction for Special Case Errors • Fixing holes • fill hole if present in both neighbor regions • more sophisticated methods can be used after
Automatic Correction for Special Case Errors • Not perfect (reduces manual effort needed) • Automatic correction (with threshold) • all threads • one thread • one node • Manual correction can be done anytime • Proofreading tool is implemented as Avizo plugin
Conclusion • Graph abstraction of segmentation data • very cheap to compute • helps in visualization • directs user to error regions • simple but provides fast method for reducing special case errors
Segmentation Details • Segmentation algorithm - Kaynig, V., Fuchs, T., Buhmann, J. M., Neuron Geometry Extraction by Perceptual Grouping in ssTEM Images, CVPR, 2010.
Tracing Details • 3D tracing (Euclidean distance of region center, overlap, difference in region size, texture similarity, smooth continuation) - Kaynig, V., Fuchs, T., Buhmann, J. M., Geometrical Consistent 3D Tracing of Neuronal Processes in ssTEM Data , MICCAI, 2010.