Skip to main content
Fig. 4 | BMC Bioinformatics

Fig. 4

From: FluoRender: joint freehand segmentation and visualization for many-channel fluorescence data analysis

Fig. 4

Freehand segmentation. (a) The user uses the mouse to paint on a visualization result to select structures. (b) Voxels are projected. The blue voxel is not selected because its projection is outside the painted region. (c) OpenCL kernels are used to estimate a threshold value. (c1) We generate a histogram for voxels within the shaded region. (c2) The histogram from the shaded region. (c3) We calculate a threshold value from the histogram. Low-intensity signals are usually noise and are excluded from the selection. (c4) Voxels with intensities higher than the threshold value are selected. (d) We cast rays backward to the viewer. The red one is rejected because its ray is obstructed by the green object. (e) We calculate a morphological diffusion to select surrounding structures of the green object based on connectivity

Back to article page