Main Content

randomAffine3d

Create randomized 3-D affine transformation

Since R2019b

崩溃了ll in page

Syntax

tform = randomAffine3d
tform = randomAffine3d(Name,Value)

Description

tform= randomAffine3dcreates anaffinetform3dobject that performs an identity transformation.

example

tform= randomAffine3d(Name,Value)specifies the type of affine transformation using name-value arguments.

Examples

崩溃了ll

Open Live Script

Create a sample volume.

volumeCube = 0.5*ones(100,100,100);

Create a 3-D viewer to control the appearance of the scene. Set the camera position of the scene to improve the visibility of the volume.

viewer = viewer3d(CameraPosition=[700 -250 650],CameraTarget=[50 50 50]);

Display the volume in the scene.

volshow(volumeCube,Parent=viewer);

Create a 3-D affine transformation that shears 3-D volumes. TherandomAffine3dfunction picks a shear amount randomly from a continuous uniform distribution within the interval [40, 60] degrees.randomAffine3dpicks a random shear direction aligned with thex-,y-, orz-axis.

tform1 = randomAffine3d(Shear=[40 60]); J1 = imwarp(volumeCube,tform1);

Display the sheared volume in a new scene with the same camera position.

viewer1 = viewer3d(CameraPosition=[700 -250 650],CameraTarget=[50 50 50]); volshow(J1,Parent=viewer1);

剪一个体积不同的随机选择amount, create a new 3-D affine transformation. Note the difference in the shear direction.

tform2 = randomAffine3d(Shear=[40 60]); J2 = imwarp(volumeCube,tform2);

Display the sheared volume in a new scene with the same camera position.

viewer2 = viewer3d(CameraPosition=[700 -250 650],CameraTarget=[50 50 50]); volshow(J2,Parent=viewer2);

Input Arguments

崩溃了ll

Name-Value Arguments

Specify optional pairs of arguments asName1=Value1,...,NameN=ValueN, whereNameis the argument name andValueis the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example:tform = randomAffine3d(XReflection=true)

Before R2021a, use commas to separate each name and value, and encloseNamein quotes.

Example:tform = randomAffine3d("XReflection",true)

随机水平反射, specified asfalseortrue. WhenXReflectionistrue(1), the transformationtformreflects images horizontally with 50% probability. By default, the transformation does not reflect images in the horizontal direction.

Random vertical reflection, specified asfalseortrue. WhenYReflectionistrue(1), the transformationtformreflects images vertically with 50% probability. By default, the transformation does not reflect images in the vertical direction.

Random reflection along the depth direction, specified asfalseortrue. WhenZReflectionistrue(1), the transformationtformreflects images along the depth direction with 50% probability. By default, the transformation does not reflect images in the depth direction.

Range of rotation applied to the input image, specified as one of the following. Rotation is measured in degrees.

  • 2-element数值向量。第二个元素亩t be larger than or equal to the first element.randomAffine3dpicks a rotation angle randomly from a continuous uniform distribution within the specified interval.randomAffine3dselects a random axis of rotation from the unit sphere.

  • A function handle of the form

    [rotationAxis,theta] = selectRotation
    The functionselectRotationmust accept no input arguments. The function must return two output arguments:rotationAxis, a 3-element vector defining the axis of rotation, andtheta, a rotation angle in degrees.

    Use a function handle to pick rotation angles from a disjoint interval or using a nonuniform probability distribution. You can also use a function handle to specify an axis of rotation. For more information about function handles, seeCreate Function Handle.

By default, the transformationtformdoes not rotate images.

Example:[-45 45]

Range of uniform (isotropic) scaling applied to the input image, specified as one of the following.

  • 2-element数值向量。第二个元素亩t be larger than or equal to the first element. The scale factor is picked randomly from a continuous uniform distribution within the specified interval.

  • A function handle. The function must accept no input arguments and return the scale factor as a numeric scalar. Use a function handle to pick scale factors from a disjoint interval or using a nonuniform probability distribution. For more information about function handles, seeCreate Function Handle.

By default, the transformationtformdoes not scale images.

Example:[0.5 4]

Range of shear applied to the input image, specified as one of the following. Shear is measured as an angle in degrees, and is in the range (–90, 90).

  • 2-element数值向量。第二个元素亩t be larger than or equal to the first element. The shear angle is picked randomly from a continuous uniform distribution within the specified interval.randomAffine3dapplies shear with uniform randomness to one of the principlex-,y-, andz-directions with respect to one of the two possible orthogonal directions.

  • A function handle. The function must accept no input arguments and return the shear angle as a numeric scalar. Use a function handle to pick a shear angle from a disjoint interval or using a nonuniform probability distribution. For more information about function handles, seeCreate Function Handle.

By default, the transformationtformdoes not shear images in the horizontal direction.

Example:[0 45]

Range of horizontal translation applied to the input image, specified as one of the following. Translation distance is measured in pixels.

  • 2-element数值向量。第二个元素亩t be larger than or equal to the first element. The translation distance is picked randomly from a continuous uniform distribution within the specified interval.

  • A function handle. The function must accept no input arguments and return the translation distance as a numeric scalar. Use a function handle to pick a translation distance from a disjoint interval or using a nonuniform probability distribution. For more information about function handles, seeCreate Function Handle.

By default, the transformationtformdoes not translate images in the horizontal direction.

Example:[-5 5]

Range of vertical translation applied to the input image, specified as one of the following. Translation distance is measured in pixels.

  • 2-element数值向量。第二个元素亩t be larger than or equal to the first element. The translation distance is picked randomly from a continuous uniform distribution within the specified interval.

  • A function handle. The function must accept no input arguments and return the translation distance as a numeric scalar. Use a function handle to pick a translation distance from a disjoint interval or using a nonuniform probability distribution. For more information about function handles, seeCreate Function Handle.

By default, the transformationtformdoes not translate images in the vertical direction.

Example:[-5 5]

Range of translation along the depth direction applied to the input image, specified as one of the following. Translation distance is measured in pixels.

  • 2-element数值向量。第二个元素亩t be larger than or equal to the first element. The translation distance is picked randomly from a continuous uniform distribution within the specified interval.

  • A function handle. The function must accept no input arguments and return the translation distance as a numeric scalar. Use a function handle to pick a translation distance from a disjoint interval or using a nonuniform probability distribution. For more information about function handles, seeCreate Function Handle.

By default, the transformationtformdoes not translate images in the depth direction.

Example:[-5 5]

Output Arguments

崩溃了ll

Affine transformation, returned as anaffinetform3dobject.

Version History

Introduced in R2019b

expand all

See Also

||

Topics