Operator Reference

hom_mat2d_scale_localT_hom_mat2d_scale_localHomMat2dScaleLocalHomMat2dScaleLocalhom_mat2d_scale_local (Operator)

hom_mat2d_scale_localT_hom_mat2d_scale_localHomMat2dScaleLocalHomMat2dScaleLocalhom_mat2d_scale_local — Add a scaling to a homogeneous 2D transformation matrix.

Signature

hom_mat2d_scale_local( : : HomMat2D, Sx, Sy : HomMat2DScale)

Herror T_hom_mat2d_scale_local(const Htuple HomMat2D, const Htuple Sx, const Htuple Sy, Htuple* HomMat2DScale)

void HomMat2dScaleLocal(const HTuple& HomMat2D, const HTuple& Sx, const HTuple& Sy, HTuple* HomMat2DScale)

HHomMat2D HHomMat2D::HomMat2dScaleLocal(const HTuple& Sx, const HTuple& Sy) const

HHomMat2D HHomMat2D::HomMat2dScaleLocal(double Sx, double Sy) const

static void HOperatorSet.HomMat2dScaleLocal(HTuple homMat2D, HTuple sx, HTuple sy, out HTuple homMat2DScale)

HHomMat2D HHomMat2D.HomMat2dScaleLocal(HTuple sx, HTuple sy)

HHomMat2D HHomMat2D.HomMat2dScaleLocal(double sx, double sy)

def hom_mat2d_scale_local(hom_mat_2d: Sequence[float], sx: Union[float, int], sy: Union[float, int]) -> Sequence[float]

Description

hom_mat2d_scale_localhom_mat2d_scale_localHomMat2dScaleLocalHomMat2dScaleLocalhom_mat2d_scale_local adds a scaling by the scale factors SxSxSxsxsx and SySySysysy to the homogeneous 2D transformation matrix HomMat2DHomMat2DHomMat2DhomMat2Dhom_mat_2d and returns the resulting matrix in HomMat2DScaleHomMat2DScaleHomMat2DScalehomMat2DScalehom_mat_2dscale. The scaling is described by a 2×2 scaling matrix S. In contrast to hom_mat2d_scalehom_mat2d_scaleHomMat2dScaleHomMat2dScalehom_mat2d_scale, it is performed relative to the local coordinate system, i.e., the coordinate system described by HomMat2DHomMat2DHomMat2DhomMat2Dhom_mat_2d; this corresponds to the following chain of transformation matrices:

The fixed point of the transformation is the origin of the local coordinate system, i.e., this point remains unchanged when transformed using HomMat2DScaleHomMat2DScaleHomMat2DScalehomMat2DScalehom_mat_2dscale.

Attention

It should be noted that homogeneous transformation matrices refer to a general right-handed mathematical coordinate system. If a homogeneous transformation matrix is used to transform images, regions, XLD contours, or any other data that has been extracted from images, the row coordinates of the transformation must be passed in the x coordinates, while the column coordinates must be passed in the y coordinates. Consequently, the order of passing row and column coordinates follows the usual order (RowRowRowrowrow,ColumnColumnColumncolumncolumn). This convention is essential to obtain a right-handed coordinate system for the transformation of iconic data, and consequently to ensure in particular that rotations are performed in the correct mathematical direction.

Note that homogeneous matrices are stored row-by-row as a tuple; the last row is usually not stored because it is identical for all homogeneous matrices that describe an affine transformation. For example, the homogeneous matrix is stored as the tuple [ra, rb, tc, rd, re, tf]. However, it is also possible to process full 3×3 matrices, which represent a projective 2D transformation.

Execution Information

  • Multithreading type: reentrant (runs in parallel with non-exclusive operators).
  • Multithreading scope: global (may be called from any thread).
  • Processed without parallelization.

Parameters

HomMat2DHomMat2DHomMat2DhomMat2Dhom_mat_2d (input_control)  hom_mat2d HHomMat2D, HTupleSequence[float]HTupleHtuple (real) (double) (double) (double)

Input transformation matrix.

SxSxSxsxsx (input_control)  number HTupleUnion[float, int]HTupleHtuple (real / integer) (double / int / long) (double / Hlong) (double / Hlong)

Scale factor along the x-axis.

Default: 2

Suggested values: 0.125, 0.25, 0.5, 1, 2, 4, 8, 16

Restriction: Sx != 0

SySySysysy (input_control)  number HTupleUnion[float, int]HTupleHtuple (real / integer) (double / int / long) (double / Hlong) (double / Hlong)

Scale factor along the y-axis.

Default: 2

Suggested values: 0.125, 0.25, 0.5, 1, 2, 4, 8, 16

Restriction: Sy != 0

HomMat2DScaleHomMat2DScaleHomMat2DScalehomMat2DScalehom_mat_2dscale (output_control)  hom_mat2d HHomMat2D, HTupleSequence[float]HTupleHtuple (real) (double) (double) (double)

Output transformation matrix.

Result

hom_mat2d_scale_localhom_mat2d_scale_localHomMat2dScaleLocalHomMat2dScaleLocalhom_mat2d_scale_local returns 2 ( H_MSG_TRUE) if both scale factors are not 0. If necessary, an exception is raised.

Possible Predecessors

hom_mat2d_identityhom_mat2d_identityHomMat2dIdentityHomMat2dIdentityhom_mat2d_identity, hom_mat2d_translate_localhom_mat2d_translate_localHomMat2dTranslateLocalHomMat2dTranslateLocalhom_mat2d_translate_local, hom_mat2d_scale_localhom_mat2d_scale_localHomMat2dScaleLocalHomMat2dScaleLocalhom_mat2d_scale_local, hom_mat2d_rotate_localhom_mat2d_rotate_localHomMat2dRotateLocalHomMat2dRotateLocalhom_mat2d_rotate_local, hom_mat2d_slant_localhom_mat2d_slant_localHomMat2dSlantLocalHomMat2dSlantLocalhom_mat2d_slant_local, hom_mat2d_reflect_localhom_mat2d_reflect_localHomMat2dReflectLocalHomMat2dReflectLocalhom_mat2d_reflect_local

Possible Successors

hom_mat2d_translate_localhom_mat2d_translate_localHomMat2dTranslateLocalHomMat2dTranslateLocalhom_mat2d_translate_local, hom_mat2d_scale_localhom_mat2d_scale_localHomMat2dScaleLocalHomMat2dScaleLocalhom_mat2d_scale_local, hom_mat2d_rotate_localhom_mat2d_rotate_localHomMat2dRotateLocalHomMat2dRotateLocalhom_mat2d_rotate_local, hom_mat2d_slant_localhom_mat2d_slant_localHomMat2dSlantLocalHomMat2dSlantLocalhom_mat2d_slant_local, hom_mat2d_reflect_localhom_mat2d_reflect_localHomMat2dReflectLocalHomMat2dReflectLocalhom_mat2d_reflect_local

See also

hom_mat2d_scalehom_mat2d_scaleHomMat2dScaleHomMat2dScalehom_mat2d_scale

Module

Foundation