/
edit.R
399 lines (374 loc) · 14.4 KB
/
edit.R
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
#' Image Editing
#'
#' Read, write and join or combine images. All image functions are vectorized, meaning
#' they operate either on a single frame or a series of frames (e.g. a collage, video,
#' or animation). Besides paths and URLs, [image_read()] supports commonly used bitmap
#' and raster object types.
#'
#' All standard base vector methods such as \link{[}, \link{[[}, [c()], [as.list()],
#' [as.raster()], [rev()], [length()], and [print()] can be used to work with magick
#' image objects. Use the standard \code{img[i]} syntax to extract a subset of the frames
#' from an image. The \code{img[[i]]} method is an alias for [image_data()] which extracts
#' a single frame as a raw bitmap matrix with pixel values.
#'
#' For reading svg or pdf it is recommended to use `image_read_svg()` and `image_read_pdf()`
#' if the [rsvg][rsvg::rsvg] and [pdftools][pdftools::pdf_render_page] R packages are available.
#' These functions provide more rendering options (including rendering of literal svg) and
#' better quality than built-in svg/pdf rendering delegates from imagemagick itself.
#'
#' X11 is required for `image_display()` which is only works on some platforms. A more
#' portable method is `image_browse()` which opens the image in a browser. RStudio has
#' an embedded viewer that does this automatically which is quite nice.
#'
#' Image objects are automatically released by the garbage collector when they are no longer
#' reachable. Because the GC only runs once in a while, you can also call `image_destroy()`
#' explicitly to release the memory immediately. This is usually only needed if you create
#' a lot of images in a short period of time, and you might run out of memory.
#'
#' @importFrom Rcpp sourceCpp
#' @useDynLib magick
#' @export
#' @family image
#' @rdname editing
#' @name editing
#' @inheritParams defines
#' @param path a file, url, or raster object or bitmap array
#' @param image magick image object returned by [image_read()] or [image_graph()]
#' @param density resolution to render pdf or svg
#' @param strip drop image comments and metadata
#' @param coalesce automatically [image_coalesce()] gif images
#' @examples
#' # Download image from the web
#' frink <- image_read("https://jeroen.github.io/images/frink.png")
#' worldcup_frink <- image_fill(frink, "orange", "+100+200", 20)
#' image_write(worldcup_frink, "output.png")
#'
#' # extract raw bitmap array
#' bitmap <- frink[[1]]
#'
#' # replace pixels with #FF69B4 ('hot pink') and convert back to image
#' bitmap[,50:100, 50:100] <- as.raw(c(0xff, 0x69, 0xb4, 0xff))
#' image_read(bitmap)
#'
#' # Plot to graphics device via legacy raster format
#' raster <- as.raster(frink)
#' par(ask=FALSE)
#' plot(raster)
#'
#' # Read bitmap arrays from other image packages
#' download.file("https://jeroen.github.io/images/example.webp", "example.webp", mode = 'wb')
#' if(require(webp)) image_read(webp::read_webp("example.webp"))
#' unlink(c("example.webp", "output.png"))
image_read <- function(path, density = NULL, depth = NULL, strip = FALSE, coalesce = TRUE, defines = NULL){
if(is.numeric(density))
density <- paste0(density, "x", density)
density <- as.character(density)
depth <- as.integer(depth)
defines <- validate_defines(defines)
image <- if(isS4(path) && methods::is(path, "Image")){
convert_EBImage(path)
} else if(inherits(path, "nativeRaster") || (is.matrix(path) && is.integer(path))){
image_read_nativeraster(path)
} else if(inherits(path, "cimg")) {
image_read_cimg((path))
} else if (grDevices::is.raster(path)) {
image_read_raster2(path)
} else if (is.matrix(path) && is.character(path)){
image_read_raster2(grDevices::as.raster(path))
} else if(is.array(path)){
image_readbitmap(path)
} else if(is.raw(path)) {
magick_image_readbin(path, density, depth, strip, defines)
} else if(is.character(path) && all(nchar(path))){
path <- vapply(path, replace_url, character(1))
# See https://github.com/ropensci/magick/issues/285
path <- if(is_windows()){
enc2utf8(path)
} else {
enc2native(path)
}
magick_image_readpath(path, density, depth, strip, defines)
} else {
stop("path must be URL, filename or raw vector")
}
if(is.character(path) && !isTRUE(magick_config()$rsvg)){
if(any(grepl("\\.svg$", tolower(path))) || any(grepl("svg|mvg", tolower(image_info(image)$format)))){
warning("ImageMagick was built without librsvg which causes poor qualty of SVG rendering.
For better results use image_read_svg() which uses the rsvg package.", call. = FALSE)
}
}
if(isTRUE(coalesce) && length(image) > 1 && identical('GIF', toupper(image_info(image)$format[1]))){
return(image_coalesce(image))
}
return(image)
}
#' @export
#' @rdname editing
#' @examples if(require(rsvg)){
#' tiger <- image_read_svg("http://jeroen.github.io/images/tiger.svg")
#' svgtxt <- '<?xml version="1.0" encoding="UTF-8"?>
#' <svg width="400" height="400" viewBox="0 0 400 400" fill="none">
#' <circle fill="steelblue" cx="200" cy="200" r="100" />
#' <circle fill="yellow" cx="200" cy="200" r="90" />
#' </svg>'
#' circles <- image_read_svg(svgtxt)
#' }
image_read_svg <- function(path, width = NULL, height = NULL){
path <- vapply(path, replace_url, character(1))
images <- lapply(path, function(x){
if(is_svg(x)) x <- charToRaw(x)
bitmap <- rsvg::rsvg_raw(x, width = width, height = height)
magick_image_readbitmap_raw(bitmap)
})
image_join(images)
}
#' @export
#' @rdname editing
#' @param pages integer vector with page numbers. Defaults to all pages.
#' @param password user [password][pdftools::pdf_render_page] to open protected pdf files
#' @examples if(require(pdftools))
#' image_read_pdf(file.path(R.home('doc'), 'NEWS.pdf'), pages = 1, density = 100)
image_read_pdf <- function(path, pages = NULL, density = 300, password = ""){
path <- replace_url(path)
if(!length(pages))
pages <- seq_len(pdftools::pdf_info(path, opw = password)$pages)
images <- lapply(pages, function(page){
bitmap <- pdftools::pdf_render_page(path, page = page, dpi = density, opw = password)
magick_image_readbitmap_raw(bitmap)
})
out <- image_join(images)
if(length(density))
try(magick_attr_density(out, paste0(density, 'x', density)))
out
}
#' @export
#' @rdname editing
#' @param fps how many images to capture per second of video. Set to
#' `NULL` to get all frames from the input video.
image_read_video <- function(path, fps = 1, format = 'png'){
if(!requireNamespace('av', quietly = TRUE) || utils::packageVersion('av') < '0.3')
stop("Please install or update the 'av' package")
images <- av::av_video_images(path, fps = fps, format = format)
on.exit(unlink(images))
image_read(images)
}
image_readbitmap <- function(x){
if(length(dim(x)) != 3)
stop("Only 3D arrays can be converted to bitmaps")
if(is.raw(x)){
magick_image_readbitmap_raw(x)
} else if(is.double(x)){
magick_image_readbitmap_double(aperm(x))
} else {
stop("Unsupported bitmap array type")
}
}
# output of dev.caputure(native = TRUE)
image_read_nativeraster <- function(x){
stopifnot(is.matrix(x) && is.integer(x))
magick_image_readbitmap_native(x)
}
# output of dev.caputure(native = FALSE) or as.raster()
image_read_raster1 <- function(x){
stopifnot(is.matrix(x) && is.character(x))
magick_image_readbitmap_raster1(t(x))
}
# output of as.raster()
image_read_raster2 <- function(x){
stopifnot(is.matrix(x) && is.character(x))
magick_image_readbitmap_raster2(x)
}
# This can probably be more efficient
image_read_cimg <- function(x){
rast <- as.raster(x)
if(is.list(rast)){
image_join(lapply(rast, image_read))
} else {
image_read(rast)
}
}
#EBImage BioConductor class
convert_EBImage <- function(x){
if(length(dim(x@.Data)) == 2)
dim(x@.Data) <- c(dim(x@.Data), 1L)
img <- if(x@colormode == 2L){
image_read(x@.Data)
} else if(x@colormode == 0L){
image_join(lapply(seq_len(dim(x@.Data)[3]), function(i){
image_read(x@.Data[,,i,drop = FALSE])
}))
} else {
stop("Unknown colormode in EBImage class")
}
image_flop(image_rotate(img, 90))
}
#' @export
#' @inheritParams effects
#' @rdname editing
#' @param flatten should image be flattened before writing? This also replaces
#' transparency with background color.
#' @param quality number between 0 and 100 for jpeg quality. Defaults to 75.
#' @param comment text string added to the image metadata for supported formats
#' @param compression a string with compression type from [compress_types]
image_write <- function(image, path = NULL, format = NULL, quality = NULL,
depth = NULL, density = NULL, comment = NULL, flatten = FALSE,
defines = NULL, compression = NULL){
assert_image(image)
if(!length(image))
warning("Writing image with 0 frames")
if(isTRUE(flatten))
image <- image_flatten(image)
format <- toupper(as.character(format))
quality <- as.integer(quality)
depth <- as.integer(depth)
density <- as.character(density)
comment <- as.character(comment)
compression <- as.character(compression)
if(length(defines)){
image_set_defines(image, defines = defines)
defines[seq_along(defines)] = NA_character_;
on.exit(image_set_defines(image, defines = defines))
}
buf <- magick_image_write(image, format, quality, depth, density, comment, compression)
if(is.character(path)){
writeBin(buf, path)
return(invisible(path))
}
return(buf)
}
#' @export
#' @rdname editing
#' @param format output format such as `"png"`, `"jpeg"`, `"gif"`, `"rgb"` or `"rgba"`.
#' @param depth color depth (either 8 or 16)
#' @param antialias enable anti-aliasing for text and strokes
#' @param type string with [imagetype](https://www.imagemagick.org/Magick++/Enumerations.html#ImageType)
#' value from [image_types][image_types] for example `grayscale` to convert into black/white
#' @param colorspace string with a [`colorspace`](https://www.imagemagick.org/Magick++/Enumerations.html#ColorspaceType)
#' from [colorspace_types][colorspace_types] for example `"gray"`, `"rgb"` or `"cmyk"`
#' @param matte set to `TRUE` or `FALSE` to enable or disable transparency
#' @param interlace string with [interlace](https://www.imagemagick.org/Magick++/Enumerations.html#InterlaceType)
image_convert <- function(image, format = NULL, type = NULL, colorspace = NULL,
depth = NULL, antialias = NULL, matte = NULL, interlace = NULL){
assert_image(image)
depth <- as.integer(depth)
antialias <- as.logical(antialias)
type <- as.character(type)
colorspace <- as.character(colorspace)
matte <- as.logical(matte)
interlace <- as.character(interlace)
if(length(depth) && is.na(match(depth, c(8, 16))))
stop('depth must be 8 or 16 bit')
magick_image_format(image, toupper(format), type, colorspace, depth, antialias, matte, interlace)
}
image_write_frame <- function(image, format = "rgba", i = 1){
magick_image_write_frame(image, format = format, i = i)
}
#' @export
#' @rdname editing
#' @param channels string with image channel(s) for example `"rgb"`, `"rgba"`,
#' `"cmyk"`,`"gray"`, or `"ycbcr"`. Default is either `"gray"`, `"rgb"` or `"rgba"`
#' depending on the image
#' @param frame integer setting which frame to extract from the image
image_data <- function(image, channels = NULL, frame = 1){
if(length(image) > 1 || frame > 1)
image <- image[frame]
if(!length(channels) || !nchar(channels)){
info <- image_info(image)
channels <- if(tolower(info$colorspace) == "gray"){
"gray"
} else if(isTRUE(info$matte)){
"rgba"
} else {
"rgb"
}
}
if(!grepl("a$", channels)) #output has no transparency channel
image <- image_flatten(image)
image_write_frame(image, format = channels)
}
#' @export
#' @rdname editing
#' @param tidy converts raster data to long form for use with [geom_raster][ggplot2::geom_raster].
#' If `FALSE` output is the same as `as.raster()`.
image_raster <- function(image, frame = 1, tidy = TRUE){
raster <- as.raster(image[frame])
if(!isTRUE(tidy))
return(raster)
data.frame(x = rep(seq_len(ncol(raster)), nrow(raster)),
y = rep(seq_len(nrow(raster)), each = ncol(raster)),
col = as.vector(raster),
stringsAsFactors = FALSE)
}
#' @export
#' @param animate support animations in the X11 display
#' @rdname editing
image_display <- function(image, animate = TRUE){
magick_image_display(image, animate)
}
#' @export
#' @param browser argument passed to [browseURL][utils::browseURL]
#' @rdname editing
image_browse <- function(image, browser = getOption("browser")){
ext <- ifelse(length(image), tolower(image_info(image[1])$format), "gif")
tmp <- tempfile(fileext = paste0(".", ext))
image_write(image, path = tmp)
utils::browseURL(tmp)
}
#' @export
#' @rdname editing
image_strip <- function(image){
assert_image(image)
magick_image_strip(image)
}
#' @export
#' @rdname editing
#' @inheritParams device
#' @inheritParams painting
#' @param pseudo_image string with [pseudo image](http://www.imagemagick.org/script/formats.php#pseudo)
#' specification for example `"radial-gradient:purple-yellow"`
#' @examples # create a solid canvas
#' image_blank(600, 400, "green")
#' image_blank(600, 400, pseudo_image = "radial-gradient:purple-yellow")
#' image_blank(200, 200, pseudo_image = "gradient:#3498db-#db3a34",
#' defines = c('gradient:direction' = 'east'))
image_blank <- function(width, height, color = "none", pseudo_image = "", defines = NULL){
width <- as.numeric(width)
height <- as.numeric(height)
color <- as.character(color)
defines <- validate_defines(defines)
magick_image_blank(width, height, color, pseudo_image, defines)
}
#' @export
#' @rdname editing
image_destroy <- function(image){
assert_image(image)
magick_image_destroy(image)
}
#' @export
#' @rdname editing
#' @param ... several images or lists of images to be combined
image_join <- function(...){
x <- unlist(list(...))
stopifnot(all(vapply(x, inherits, logical(1), "magick-image")))
magick_image_join(x)
}
#' @export
#' @rdname editing
image_attributes <- function(image){
assert_image(image)
magick_image_properties(image)
}
#' @export
#' @rdname editing
#' @param artifact string with name of the artifact to extract, see the
#' [image_deskew] for an example.
image_get_artifact <- function(image, artifact = ""){
assert_image(image)
artifact <- as.character(artifact)
magick_image_artifact(image, artifact)
}
#' @export
#' @rdname editing
demo_image <- function(path){
image_read(system.file('images', path, package = 'magick'))
}