rotate_image🔗
Short description🔗
rotate_image — Rotate an image about its center.
Signature🔗
rotate_image( image Image, out image ImageRotate, angle.deg Phi, string Interpolation )
Description🔗
rotate_image rotates the Image counterclockwise by
Phi degrees about its center and stores the result in the
output image ImageRotate. The output image has the same
size as the input image. The only exception are rotations by 90 and
270 degrees where width and height will be exchanged. The domain of
the input image is ignored, i.e., assumed to be the full rectangle
of the image. The domain of the output image is the intersection of
the transformed rectangle and the rectangle of the output image.
If Phi is a multiple of 90 degrees, this operator is much
faster, especially than the general operator
affine_trans_image. The effect of the parameter
Interpolation is the same as in affine_trans_image.
It is ignored for rotations by 90, 180, and 270 degrees. If it is
necessary to rotate the domain, too, the operator
projective_trans_image must be used.
Additionally, for images of type byte, int2 or uint2 the system parameter 'int_zooming' selects between fast calculation in fixed point arithmetics ('int_zooming' = 'true') and highly accurate calculation in floating point arithmetics ('int_zooming' = 'false'). Except for rotations by 90, 180, or 270 degrees, fixed point calculation can lead to minor gray value deviations. Furthermore, the domain of resulting images can differ as well.
Attention🔗
The domain of the input image is ignored, i.e., assumed to be the
full rectangle of the image. The domain of the output image is the
intersection of the transformed rectangle and the rectangle of the
output image. The angle Phi is given in degrees, not in
radians. For rotations by 90, 180, and 270 degrees
rotate_image is not parallelized internally.
rotate_image can be executed on OpenCL devices if the input
image does not exceed the maximum size of image objects of the
selected device. Due to numerical reasons, there can be slight
differences in the output compared to the execution on the CPU.
Execution information🔗
Execution information
-
Supports OpenCL compute devices.
-
Multithreading type: reentrant (runs in parallel with non-exclusive operators).
-
Multithreading scope: global (may be called from any thread).
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Automatically parallelized on tuple level.
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Automatically parallelized on channel level.
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Automatically parallelized on internal data level.
Parameters🔗
Image (input_object) (multichannel-)image(-array) → object (byte* / int2* / uint2* / real*) *allowed for compute devices
Input image.
ImageRotate (output_object) (multichannel-)image(-array) → object (byte / int2 / uint2 / real)
Rotated image.
Phi (input_control) angle.deg → (real / integer)
Rotation angle.
Default: 90
Suggested values: 90, 180, 270
Value range: 0 ≤ Phi ≤ 360
Minimum increment: 0.001
Recommended increment: 0.2
Interpolation (input_control) string → (string)
Type of interpolation.
Default: 'constant'
List of values: 'bicubic', 'bilinear', 'constant', 'nearest_neighbor', 'weighted'
Example🔗
(HDevelop)
read_image(Image,'monkey')
dev_display (Image)
rotate_image(Image,RotImage,270,'constant')
dev_display (RotImage)
read_image(&Image,"monkey")\;
disp_image(Image,WindowHandle)\;
rotate_image(Image,&RotImage,270,'constant')\;
disp_image(RotImage,WindowHandle)\;
Combinations with other operators🔗
Module🔗
Foundation