G'MIC - GREYC's Magic for Image Computing: A Full-Featured Open-Source Framework for Image Processing
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A Full-Featured Open-Source Framework for Image Processing

Latest stable version: 3.5.5        Current pre-release: 3.6.0 (2025/08/04)

Reference
Table of Contents  ▸  List of Commands  ▸  Features Extraction  ▸  at_quadrangle◀  at_curve    |    barycenter  ▶

at_quadrangle

Arguments:

  • x0[%],y0[%],x1[%],y1[%],x2[%],y2[%],x3[%],y3[%],_interpolation,_boundary_conditions    or
  • x0[%],y0[%],z0[%],x1[%],y1[%],z1[%],x2[%],y2[%],z2[%],x3[%],y3[%],z3[%],_interpolation,_boundary_conditions

Description:

Retrieve pixels of the selected images belonging to the specified 2D or 3D quadrangle.

interpolation can be { 0:Nearest-neighbor | 1:Linear | 2:Cubic }.
boundary_conditions can be { 0:Dirichlet | 1:Neumann | 2:Periodic | 3:Mirror }.

Example of use:

image.jpg params=5%,5%,95%,5%,60%,95%,40%,95% +at_quadrangle $params polygon.. 4,$params,0.5,255

Command: image.jpg params=5%,5%,95%,5%,60%,95%,40%,95% +at_quadrangle $params polygon.. 4,$params,0.5,255
Command: image.jpg params=5%,5%,95%,5%,60%,95%,40%,95% +at_quadrangle $params polygon.. 4,$params,0.5,255
G'MIC - GREYC's Magic for Image Computing: A Full-Featured Open-Source Framework for Image Processing

G'MIC is an open-source software distributed under the CeCILL free software licenses (LGPL-like and/or
GPL-compatible). Copyrights (C) Since July 2008, David Tschumperlé - GREYC UMR CNRS 6072, Image Team.