Use 'magick' package for resize()

DESCRIPTION

@@ -6,6 +6,7 @@ Authors@R: c(
     person("Yihui", "Xie", role = "ctb"),
     person("Francois", "Guillem", role = "ctb"),
     person("Barret", "Schloerke", role = "ctb"),
+    person("Thomas", "Leeper", role = "ctb"),
     person("Nicolas", "Perriault", role = "ctb", comment = "The CasperJS library")
     )
 Description: Takes screenshots of web pages, including Shiny applications and R
@@ -15,6 +16,7 @@ Depends:
 Imports:
     magrittr,
     jsonlite,
+    magick,
     callr
 Suggests:
     httpuv,
@@ -23,9 +25,7 @@ Suggests:
     shiny
 VignetteBuilder: knitr
 License: GPL-2
-SystemRequirements: PhantomJS (http://phantomjs.org) for taking screenshots,
-    ImageMagick (http://www.imagemagick.org) or GraphicsMagick
-    (http://www.graphicsmagick.org) and OptiPNG (http://optipng.sourceforge.net)
-    for manipulating images.
+SystemRequirements: PhantomJS (http://phantomjs.org) for taking screenshots
+    and OptiPNG (http://optipng.sourceforge.net) for manipulating images.
 RoxygenNote: 6.0.1
 URL: https://github.com/wch/webshot/

NAMESPACE

@@ -10,4 +10,5 @@ export(resize)
 export(rmdshot)
 export(shrink)
 export(webshot)
+import(magick)
 importFrom(magrittr,"%>%")

NEWS.md

@@ -7,6 +7,8 @@ webshot 0.5.0.9000
 
 * Added `appshot.shiny.appobj` functionality (schloerke, [#55](https://github.com/wch/webshot/pull/55))
 
+* Removed system dependencies on GraphicsMagick/ImageMagick by using the **magick** package in `resize()`.
+
 webshot 0.5.0
 =============
 

R/appshot.R

@@ -107,7 +107,7 @@ appshot.shiny.appobj <- function(
   p <- r_background_process(
     function(url, file, ..., timeout) {
       # Wait for app to start
-      wait <- getFromNamespace("wait_until_server_exists", "webshot")
+      wait <- utils::getFromNamespace("wait_until_server_exists", "webshot")
       wait(url, timeout = timeout)
       webshot::webshot(url = url, file = file, ...)
     },

R/image.R

@@ -1,8 +1,7 @@
 #' Resize an image
 #'
 #' This does not change size of the image in pixels, nor does it affect
-#' appearance -- it is lossless compression. This requires GraphicsMagick
-#' (recommended) or ImageMagick to be installed.
+#' appearance -- it is lossless compression.
 #'
 #' @param filename Character vector containing the path of images to resize.
 #' @param geometry Scaling specification. Can be a percent, as in \code{"50\%"},
@@ -21,6 +20,7 @@
 #'   webshot("https://www.r-project.org/", "r-small-2.png") %>%
 #'     resize("400x")
 #' }
+#' @import magick
 #' @export
 resize <- function(filename, geometry) {
   mapply(resize_one, filename = filename, geometry = geometry,
@@ -29,39 +29,9 @@ resize <- function(filename, geometry) {
 }
 
 resize_one <- function(filename, geometry) {
-  # Handle missing phantomjs
-  if (is.null(filename)) return(NULL)
-
-  # First look for graphicsmagick, then imagemagick
-  prog <- Sys.which("gm")
-
-  if (prog == "") {
-    # ImageMagick 7 has a "magick" binary
-    prog <- Sys.which("magick")
-  }
-
-  if (prog == "") {
-    if (is_windows()) {
-      prog <- find_magic()
-    } else {
-      prog <- Sys.which("convert")
-    }
-  }
-
-  if (prog == "")
-    stop("None of `gm`, `magick`, or `convert` were found in path. GraphicsMagick or ImageMagick must be installed and in path.")
-
-  args <- c(filename, "-resize", geometry, filename)
-
-  if (names(prog) %in% c("gm", "magick")) {
-    args <- c("convert", args)
-  }
-
-  res <- system2(prog, args)
-
-  if (res != 0)
-    stop ("Resizing with `gm convert`, `magick convert` or `convert` failed.")
-
+  img <- image_read(filename)
+  img_out <- image_resize(img, geometry)
+  image_write(img_out, filename)
   filename
 }
 

R/utils.R

@@ -291,46 +291,3 @@ fix_windows_url <- function(url) {
 
   vapply(url, fix_one, character(1), USE.NAMES = FALSE)
 }
-
-
-# Borrowed from animation package, with some adaptations.
-find_magic = function() {
-  # try to look for ImageMagick in the Windows Registry Hive, the Program Files
-  # directory and the LyX installation
-  if (!inherits(try({
-    magick.path = utils::readRegistry('SOFTWARE\\ImageMagick\\Current')$BinPath
-  }, silent = TRUE), 'try-error')) {
-    if (nzchar(magick.path)) {
-      convert = normalizePath(file.path(magick.path, 'convert.exe'), "/", mustWork = FALSE)
-    }
-  } else if (
-    nzchar(prog <- Sys.getenv('ProgramFiles')) &&
-      length(magick.dir <- list.files(prog, '^ImageMagick.*')) &&
-      length(magick.path <- list.files(file.path(prog, magick.dir), pattern = '^convert\\.exe$',
-                                       full.names = TRUE, recursive = TRUE))
-  ) {
-    convert = normalizePath(magick.path[1], "/", mustWork = FALSE)
-  } else if (!inherits(try({
-    magick.path = utils::readRegistry('LyX.Document\\Shell\\open\\command', 'HCR')
-  }, silent = TRUE), 'try-error')) {
-    convert = file.path(dirname(gsub('(^\"|\" \"%1\"$)', '', magick.path[[1]])), c('..', '../etc'),
-                        'imagemagick', 'convert.exe')
-    convert = convert[file.exists(convert)]
-    if (length(convert)) {
-      convert = normalizePath(convert, "/", mustWork = FALSE)
-    } else {
-      warning('No way to find ImageMagick!')
-      return("")
-    }
-  } else {
-    warning('ImageMagick not installed yet!')
-    return("")
-  }
-
-  if (!file.exists(convert)) {
-    # Found an ImageMagick installation, but not the convert.exe binary.
-    warning("ImageMagick's convert.exe not found at ", convert)
-    return("")
-  }
-  return(convert)
-}

README.Rmd

@@ -116,7 +116,7 @@ rmdshot("document.rmd", "document.png")
 
 ### Manipulating images
 
-If you have GraphicsMagick (recommended) or ImageMagick installed, you can pass the result to `resize()` to resize the image after taking the screenshot. This can take any valid ImageMagick geometry specifictaion, like `"75%"`, or `"400x"` (for an image 400 pixels wide). However, you may get different (and often better) results by using the `zoom` option: the fonts and graphical elements will render more sharply. However, compared to simply resizing, zooming out may result in slightly different positioning of text and layout elements.
+You can pass the result to `resize()` to resize the image after taking the screenshot. This can take any valid ImageMagick geometry specifictaion, like `"75%"`, or `"400x"` (for an image 400 pixels wide). However, you may get different (and often better) results by using the `zoom` option: the fonts and graphical elements will render more sharply. However, compared to simply resizing, zooming out may result in slightly different positioning of text and layout elements.
 
 You can also call `shrink()`, which runs [OptiPNG](http://optipng.sourceforge.net/) to shrink the PNG file losslessly.
 

README.md

@@ -1,3 +1,7 @@
+---
+output: github_document
+---
+
 
 webshot
 =======
@@ -6,60 +10,66 @@ webshot
 
 **Webshot** makes it easy to take screenshots of web pages from R. It can also:
 
--   Run Shiny applications locally and take screenshots of the application.
--   Render R Markdown documents and take screenshots of the document. Webshot can handle both static Rmd documents and interactive ones (those with `runtime: shiny`).
+* Run Shiny applications locally and take screenshots of the application.
+* Render R Markdown documents and take screenshots of the document. Webshot can handle both static Rmd documents and interactive ones (those with `runtime: shiny`).
 
-Installation
-------------
+## Installation
 
 Webshot can be installed from CRAN. Webshot also requires the external program [PhantomJS](http://phantomjs.org/). You may either download PhantomJS from its website, or use the function `webshot::install_phantomjs()` to install it automatically.
 
-``` r
+
+```r
 install.packages("webshot")
 webshot::install_phantomjs()
 ```
 
-Usage
------
+
+## Usage
 
 By default, `webshot` will use a 992x744 pixel viewport (a virtual browser window) and take a screenshot of the entire page, even the portion outside the viewport.
 
-``` r
+
+```r
 library(webshot)
 webshot("https://www.r-project.org/", "r.png")
 webshot("https://www.r-project.org/", "r.pdf") # Can also output to PDF
 ```
 
 You can clip it to just the viewport region:
 
-``` r
+
+```r
 webshot("https://www.r-project.org/", "r-viewport.png", cliprect = "viewport")
 ```
 
 You can also get screenshots of a portion of a web page using CSS selectors. If there are multiple matches for the CSS selector, it will use the first match.
 
-``` r
+
+```r
 webshot("https://www.r-project.org/", "r-sidebar.png", selector = ".sidebar")
 ```
 
 If you supply multiple CSS selectors, it will take a screenshot containing all of the selected items.
 
-``` r
+
+```r
 webshot("https://www.r-project.org/", "r-selectors.png",
         selector = c("#getting-started", "#news"))
 ```
 
 The clipping rectangle can be expanded to capture some area outside the selected items:
 
-``` r
+
+```r
 webshot("https://www.r-project.org/", "r-expand.png",
         selector = "#getting-started",
         expand = c(40, 20, 40, 20))
 ```
 
 You can take higher-resolution screenshots with the `zoom` option. This isn't exactly the same as taking a screenshot with a HiDPI ("Retina") device: it is like increasing the zoom to 200% in a desktop browser and doubling the height and width of the browser window. This differs from using a HiDPI device because some web pages load different, higher-resolution images when they know they will be displayed on a HiDPI device (but using zoom will not report that there is a HiDPI device).
 
-``` r
+
+```r
 webshot("https://www.r-project.org/", "r-sidebar-zoom.png",
         selector = ".sidebar", zoom = 2)
 ```
@@ -68,7 +78,8 @@ webshot("https://www.r-project.org/", "r-sidebar-zoom.png",
 
 All parameters of function `webshot`. That means that multiple screenshots can be taken with a single command. When taking a lot of screenshots, vectorization can divide by 5 the execution time.
 
-``` r
+
+```r
 # Take a screenshot of different sites
 webshot(c("https://www.r-project.org/", "https://github.com/wch/webshot"),
         file = c("r.png", "webshot.png"))
@@ -85,33 +96,40 @@ webshot("http://rstudio.github.io/leaflet/",
         selector = list("#features", "#installation"))
 ```
 
+
+
 ### Screenshots of Shiny applications
 
 The `appshot()` function will run a Shiny app locally in a separate R process, and take a screenshot of it. After taking the screenshot, it will kill the R process that is running the Shiny app.
 
-``` r
+
+```r
 # Get the directory of one of the Shiny examples
 appdir <- system.file("examples", "01_hello", package="shiny")
 appshot(appdir, "01_hello.png")
 ```
 
+
 ### Screenshots of R Markdown documents
 
 The `rmdshot()` function takes screenshots of R Markdown documents. For static R Markdown documents, it renders them to HTML in a temporary directory (using `rmarkdown::render()`)and then takes a screenshot.
 
 For dynamic R Markdown documents, it runs them using `rmarkdown::run()` in a separate R process and then takes a screenshot. After taking the screenshot, it will kill the R process that is running the document.
 
-``` r
+
+```r
 rmdshot("document.rmd", "document.png")
 ```
 
+
 ### Manipulating images
 
-If you have GraphicsMagick (recommended) or ImageMagick installed, you can pass the result to `resize()` to resize the image after taking the screenshot. This can take any valid ImageMagick geometry specifictaion, like `"75%"`, or `"400x"` (for an image 400 pixels wide). However, you may get different (and often better) results by using the `zoom` option: the fonts and graphical elements will render more sharply. However, compared to simply resizing, zooming out may result in slightly different positioning of text and layout elements.
+You can pass the result to `resize()` to resize the image after taking the screenshot. This can take any valid ImageMagick geometry specifictaion, like `"75%"`, or `"400x"` (for an image 400 pixels wide). However, you may get different (and often better) results by using the `zoom` option: the fonts and graphical elements will render more sharply. However, compared to simply resizing, zooming out may result in slightly different positioning of text and layout elements.
 
 You can also call `shrink()`, which runs [OptiPNG](http://optipng.sourceforge.net/) to shrink the PNG file losslessly.
 
-``` r
+
+```r
 webshot("https://www.r-project.org/", "r-small-resized.png") %>%
   resize("75%") %>%
   shrink()
@@ -126,6 +144,9 @@ webshot("https://www.r-project.org/", "r-small.png") %>%
   shrink()
 ```
 
+
+
+
 To illustrate the difference between `resize()` and `zoom`, here is an image with `resize("50%")`:
 
 ![](tools/r-small-resized.png)

vignettes/intro.Rmd

@@ -115,7 +115,7 @@ appdir <- system.file("examples", "01_hello", package="shiny")
 appshot(appdir, delay = 3)
 ```
 
-There are two functions `resize()` and `shrink()` to manipulate images, which require GraphicsMagick (or ImageMagick) and OptiPNG, respectively. A simple example:
+There are two functions `resize()` and `shrink()` to manipulate images, that latter of which requires OptiPNG, respectively. A simple example:
 
 ```{r eval=FALSE}
 # Result can be piped to other commands like resize() and shrink()