algorithms.resample¶
Module: algorithms.resample¶
Some simple examples and utility functions for resampling.
Functions¶
- nipy.algorithms.resample.resample(image, target, mapping, shape, order=3, mode='constant', cval=0.0)¶
Resample image to target CoordinateMap
Use a “world-to-world” mapping mapping and spline interpolation of a order.
Here, “world-to-world” refers to the fact that mapping should be a callable that takes a physical coordinate in “target” and gives a physical coordinate in “image”.
- Parameters:
- imageImage instance
image that is to be resampled.
- targetCoordinateMap
coordinate map for output image.
- mappingcallable or tuple or array
transformation from target.function_range to image.coordmap.function_range, i.e. ‘world-to-world mapping’. Can be specified in three ways: a callable, a tuple (A, b) representing the mapping y=dot(A,x)+b or a representation of this mapping as an affine array, in homogeneous coordinates.
- shapesequence of int
shape of output array, in target.function_domain.
- orderint, optional
what order of interpolation to use in
scipy.ndimage.- modestr, optional
Points outside the boundaries of the input are filled according to the given mode (‘constant’, ‘nearest’, ‘reflect’ or ‘wrap’). Default is ‘constant’.
- cvalscalar, optional
Value used for points outside the boundaries of the input if mode=’constant’. Default is 0.0.
- Returns:
- outputImage instance
Image has interpolated data and output.coordmap == target.
- nipy.algorithms.resample.resample_img2img(source, target, order=3, mode='constant', cval=0.0)¶
Resample source image to space of target image
This wraps the resample function to resample one image onto another. The output of the function will give an image with shape of the target and data from the source.
- Parameters:
- source
Image Image instance that is to be resampled
- target
Image Image instance to which source is resampled. The output image will have the same shape as the target, and the same coordmap.
- order
int, optional What order of interpolation to use in
scipy.ndimage.- modestr, optional
Points outside the boundaries of the input are filled according to the given mode (‘constant’, ‘nearest’, ‘reflect’ or ‘wrap’). Default is ‘constant’.
- cvalscalar, optional
Value used for points outside the boundaries of the input if mode=’constant’. Default is 0.0.
- source
- Returns:
- output
Image Image with interpolated data and output.coordmap == target.coordmap
- output
Examples
>>> from nipy.testing import funcfile, anatfile >>> from nipy.io.api import load_image >>> aimg_source = load_image(anatfile) >>> aimg_target = aimg_source >>> # in this case, we resample aimg to itself >>> resimg = resample_img2img(aimg_source, aimg_target)