\name{readImage} \alias{readImage} \alias{writeImage} \concept{image IO} \title{Image I/O} \description{ Functions to read and write images from/to files and URL's. The supported image formats depend on the capabilities of ImageMagick. } \usage{ readImage(files, colormode) writeImage(x, files, quality = 100) } \arguments{ \item{files}{A character vector of file names or URLs. If missing, an interactive file chooser is displayed.} \item{x}{An \code{\linkS4class{Image}} object or an array.} \item{quality}{A numeric, ranging from 1 to 100. Default is 100.} \item{colormode}{Deprecated.} } \value{ \code{readImage} returns a new \code{Image} object. \code{writeImage} returns \code{invisible(files)}. } \details{ When writing images in formats supporting lossy compression (like JPEG), the quality can be specified used a \code{quality} value in the range \code{[1,100]}. The best quality is obtained with 100. The file format is deduced from the file name extension. \code{ImageMagick} is used to perform all image I/O operations. Therefore, the package supports all the file types supported by \code{ImageMagick}. When reading images, files of different formats can be mixed in any sequence, including mixing single 2D images with TIFF image stacks. The result will contain a stack with all images and stacks, at the size of the first image read. Subsequent images are cropped (if larger) or filled with background (if smaller). } \references{ ImageMagick: \url{http://www.imagemagick.org} } \author{ Oleg Sklyar, \email{osklyar@ebi.ac.uk}, 2005-2006 } \examples{ ## Reads and display images f = system.file("images", "lena-color.png", package="EBImage") x = readImage(f) if (interactive()) display(x) x = readImage(system.file("images", "nuclei.tif", package="EBImage")) if (interactive()) display(x) try({ im = readImage("http://www.google.com/intl/en/images/logo.gif") if (interactive()) display(im) }) ## Converts a TIFF file into JPEG f1 = system.file("images", "lena-color.png", package="EBImage") x1 = readImage(f1) f2 = paste(tempfile(), "jpeg", sep=".") writeImage(x1, f2) cat("Converted '", f1, "' into '", f2, "'.\n", sep='') }