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+.. _affine:
+
+================================================================================
+Affine transformation
+================================================================================
+
+.. versionadded:: 6.0.0
+
+The affine transformation applies translation and scaling/rotation terms on the
+x,y,z coordinates, and translation and scaling on the temporal cordinate.
+
++---------------------+----------------------------------------------------------+
+| **Alias**           | affine                                                   |
++---------------------+----------------------------------------------------------+
+| **Domain**          | 4D                                                       |
++---------------------+----------------------------------------------------------+
+| **Input type**      | XYZT                                                     |
++---------------------+----------------------------------------------------------+
+| **output type**     | XYZT                                                     |
++---------------------+----------------------------------------------------------+
+
+By default, the parameters are set for an identity transforms. The transformation
+is reversible unless the determinant of the sji matrix is 0, or `tscale` is 0
+
+
+Parameters
+################################################################################
+
+Optional
+-------------------------------------------------------------------------------
+
+.. option:: +xoff=<value>
+
+    Offset in X. Default value: 0
+
+.. option:: +yoff=<value>
+
+    Offset in Y. Default value: 0
+
+.. option:: +zoff=<value>
+
+    Offset in Z. Default value: 0
+
+.. option:: +toff=<value>
+
+    Offset in T. Default value: 0
+
+.. option:: +s11=<value>
+
+    Rotation/scaling term. Default value: 1
+
+.. option:: +s12=<value>
+
+    Rotation/scaling term. Default value: 0
+
+.. option:: +s13=<value>
+
+    Rotation/scaling term. Default value: 0
+
+.. option:: +s21=<value>
+
+    Rotation/scaling term. Default value: 0
+
+.. option:: +s22=<value>
+
+    Rotation/scaling term. Default value: 1
+
+.. option:: +s23=<value>
+
+    Rotation/scaling term. Default value: 0
+
+.. option:: +s31=<value>
+
+    Rotation/scaling term. Default value: 0
+
+.. option:: +s32=<value>
+
+    Rotation/scaling term. Default value: 0
+
+.. option:: +s33=<value>
+
+    Rotation/scaling term. Default value: 1
+
+.. option:: +tscale=<value>
+
+    Time scaling term. Default value: 1
+
+
+
+Mathematical description
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+
+.. math::
+    :label: formula
+
+    \begin{align}
+        \begin{bmatrix}
+            X \\
+            Y \\
+            Z \\
+            T \\
+        \end{bmatrix}^{dest} =
+        \begin{bmatrix}
+            xoff \\
+            yoff \\
+            zoff \\
+            toff \\
+        \end{bmatrix} +
+        \begin{bmatrix}
+             s11 & s12 & s13 & 0 \\
+             s21 & s22 & s23 & 0 \\
+             s31 & s32 & s33 & 0 \\
+             0   & 0   & 0   & tscale \\
+        \end{bmatrix}
+        \begin{bmatrix}
+            X \\
+            Y \\
+            Z \\
+            T \\
+        \end{bmatrix}^{source}
+    \end{align}
+
+