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imager (version 0.45.8)

Image Processing Library Based on 'CImg'

Description

Fast image processing for images in up to 4 dimensions (two spatial dimensions, one time/depth dimension, one colour dimension). Provides most traditional image processing tools (filtering, morphology, transformations, etc.) as well as various functions for easily analysing image data using R. The package wraps 'CImg', , a simple, modern C++ library for image processing.

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Install

install.packages('imager')

Monthly Downloads

9,144

Version

0.45.8

License

LGPL-3

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Repository

https://github.com/asgr/imager/

Homepage

https://asgr.github.io/imager/

Maintainer

Last Published

February 20th, 2024

Functions in imager (0.45.8)

Autocrop image region

Compute the bounding box of a pixset

Convert a cimg object to a raster object for plotting

blur_anisotropic

Blur image anisotropically, in an edge-preserving way.

Center stencil at a location

Capture the current R plot device as a cimg image

Canny edge detector

Photograph of sailing boats from Kodak set

Blur image with a box filter (square window)

Find the boundary of a shape in a pixel set

Clean up and fill in pixel sets (morphological opening and closing)

Add circles to plot

Control CImg's parallelisation

Split a colour image into a list of separate channels

Convert cimg to spatstat im object

cimg.dimensions

Image dimensions

Return contours of image/pixset

Various shortcuts for extracting colour channels, frames, etc

Methods to convert various objects to pixsets

Display image using CImg library

Display object using CImg library

Display image list using CImg library

Estimate displacement field between two images.

distance_transform

Compute Euclidean distance function to a specified value.

Draw circle on image

Return coordinates of subset of pixels

Flatten alpha channel

Fill in a colour in an area given by a pixset

Blur image with a box filter.

Various useful pixsets

Crop the outer margins of an image

Grow/shrink a pixel set

Correlation/convolution of image by filter

Create a cimg object

Concatenation for image lists

Apply recursive Deriche filter.

Select image regions interactively

Check that value is in a range

Convert an RGB image to grayscale

Highlight pixel set on image

Split an image, apply function, recombine the results as an image

Return pixel values in a neighbourhood defined by a stencil

Split an image along axis, apply function, return a list

Circle detection using Hough transform

Replace part of an image with another

Array subset operator for cimg objects

Split a video into separate frames

Evaluation in an image context

Split an image along a certain axis (producing a list)

imager: an R library for image processing, based on CImg

Draw image on another image

Grayscale dimensions of image

Coordinates from pixel index

Draw rectangle on image

Draw text on an image

Split an image along a certain axis (producing a list)

Coordinates as images

Compute Haar multiscale wavelet transform.

Generates a "dirac" image, i.e. with all values set to 0 except one.

Select part of an image

Replicate images

Rotate an image along the XY plane.

Compute image gradient

Combining images

Return image hessian.

Erode/dilate image by a structuring element.

Colour space conversions in imager

diffusion_tensors

Compute field of diffusion tensors for edge-preserving smoothing.

Create an image of custom size by filling in repeated values

Combine a list of images into a single image

Compute image hessian.

Interpolate image values

Check that an object is an imlist object

Load all images in a directory

Return information on image file

Checks that an object is a cimg object

Type-stable map for use with the purrr package

Shift image content.

Plot a line, Hesse normal form parameterisation

Apply function to each element of a list, then combine the result as an image by appending along specified axis

Mutate a data frame by adding new or replacing existing columns.

Mirror image content along specified axis

Check that an object is a pixset object

Blur image with the median filter. In a window of size n x n centered at pixel (x,y), compute median pixel value over the window. Optionally, ignore values that are too far from the value at current pixel.

Make/save a video using ffmpeg

resize_doubleXY

Resize image uniformly

Pixel sets (pixsets)

Return the pixel grid for an image

extract_patches

Extract image patches and return a list

Compute image gradient.

Hough transform for lines

Remove alpha channel and store as attribute

Load example image

Compute image Laplacian

Renormalise image

Split an image along axis, map function, return a data.frame

Fill-in NA values in an image

Load image from file or URL

Build simple interactive interfaces using imager

Return image patch summary

Permute image axes

Compute the periodic part of an image, using the periodic/smooth decomposition of Moisan (2011)

Display an image using base graphics

Generate (Gaussian) white-noise image

Plot objects on image using base graphics

Modify parts of an image

Threshold grayscale image

Select a region of homogeneous colour

A cross-shaped stencil

Plot an image list

Pad image with n pixels along specified axis

Label connected components.

Rotate image by an arbitrary angle, around a center point.

patch_summary_cimg

Extract a numerical summary from image patches, using CImg's mini-language Experimental feature.

Blur image isotropically.

Young-Van Vliet recursive Gaussian filter.

Compute watershed transform.

Return locations in pixel set

Linear index in internal vector from pixel coordinates

Load a video using ffmpeg

px.remove_outer

Remove all connected regions that touch image boundaries

A pixset for NA values

Remove empty dimensions from an array

Convert a magick image to a cimg image or image list and vice versa

split_connected

Split pixset into connected components

Convert a raster object to a cimg object

Convert a RasterLayer/RasterBrick to a cimg image/image list

Convert to cimg object

Convert an image in spatstat format to an image in cimg format

as.cimg.data.frame

Create an image from a data.frame

Compute the Discrete Fourier Transform of an image

as.cimg.function

Create an image by sampling a function

Add colour channels to a grayscale image or pixel set

as.data.frame.imlist

Convert image list to data.frame

as.igraph.pixset

Form an adjacency graph from a pixset

as.data.frame.cimg

Convert a pixel image to a data.frame

as.data.frame.pixset

Methods to convert pixsets to various objects

Convert various objects to image lists

Turn an numeric array into a cimg object

Form a graph from an image

Return or set pixel value at coordinates