| Title: | Pencil Sketch Effect |
| Version: | 0.1.3 |
| Description: | An implementation of image processing effects that convert a photo into a line drawing image. For details, please refer to Tsuda, H. (2020). sketcher: An R package for converting a photo into a sketch style image. <doi:10.31234/osf.io/svmw5>. |
| URL: | https://htsuda.net/sketcher/ |
| BugReports: | https://github.com/tsuda16k/sketcher/issues/ |
| License: | MIT + file LICENSE |
| Encoding: | UTF-8 |
| LazyData: | true |
| RoxygenNote: | 7.1.0 |
| Imports: | jpeg, png, readbitmap, downloader, imager, magrittr, methods, stringr, dplyr |
| Depends: | R (≥ 2.10) |
| Suggests: | knitr, rmarkdown |
| NeedsCompilation: | no |
| Packaged: | 2020-05-14 06:19:38 UTC; tsuhir |
| Author: | Hiroyuki Tsuda 
[aut, cre] |
| Maintainer: | Hiroyuki Tsuda <tsuda16k@gmail.com> |
| Repository: | CRAN |
| Date/Publication: | 2020-05-25 09:10:02 UTC |
A face image.
Description
A photograph obtained from a free stock photos site. pexels.com/photo/man-about-to-touch-his-face-wearing-blue-suit-718261/
Usage
face
Format
An array with 600 x 460 * 3 dimensions. Each dimension represents y-coordinate, x-coordinate, and color channel.
Examples
plot(face)
Load image from file or URL
Description
Load image from file or URL
Usage
im_load(file, name)
Arguments
file |
path to file or URL |
name |
a string for name attribute. if missing, inferred from the file argument. |
Value
an array of image data
Examples
## Not run:
# load an image from disk
im = im_load("path/to/your/image.jpg")
plot(im)
# load an image from URL
im = im_load("http://placehold.jp/150x150.png")
## End(Not run)
Save an image to disk
Description
Save an image to disk
Usage
im_save(im, name, path, format = "png", quality = 0.95)
Arguments
im |
An image. |
name |
Name of the image file. |
path |
Path to file. |
format |
Image format. Either "jpg", "png", "tiff", or "bmp". Default is "png". |
quality |
(jpg only) default is 0.95. Higher quality means less compression. |
Value
No return value, called for side effects.
Examples
## Not run:
im = sketch(face)
# im.png is saved to the current working directory
im_save( im, name = "im", path = getwd() )
# myimage.jpg is saved to a specified directory
im_save( im, name = "myimage", path = "path/to/image", format = "jpg" )
## End(Not run)
Display an image
Description
Display an image
Usage
## S3 method for class 'nimg'
plot(x, rescale = FALSE, ...)
Arguments
x |
an image |
rescale |
logical. if true, then pixel value is rescaled to range between 0 and 1. |
... |
other parameters to be passed to plot.default |
Value
No return value, called for side effects.
Examples
plot(face)
Apply the sketch effect on an image
Description
Apply the sketch effect on an image
Usage
sketch(
im,
style = 1,
lineweight = 1,
smooth = ceiling(lineweight),
gain = 0.02,
contrast = NULL,
shadow = 0,
max.size = 2048
)
Arguments
im |
an image (array). |
style |
a numeric (integer). Either 1 or 2. |
lineweight |
a numeric. Strength of lines. |
smooth |
a numeric (integer). Smoothness of image texture. |
gain |
a numeric between 0 and 1. Can be used to reduce noise in dim regions. |
contrast |
a numeric (integer). Adjusts the image contrast. |
shadow |
a numeric between 0 and 1 |
max.size |
maximum image resolution (width or height) of the output image |
Value
an image.
Examples
im = sketch(face)
plot(im)
## Not run:
im = im_load("path/to/your/image.jpg")
plot(im)
## End(Not run)
Create multiple sketches at once and combine them into a single image
Description
It is often necessary to find optimal sketch style parameters for your task. With this function, you can easily compare the effects of different style parameters.
Usage
survey(
im,
style = 1,
weight_levels = c(1, 2, 4),
smooth_levels = c(1, 2, 4),
gain = 0.02,
contrast = NULL,
shadow = 0,
verbose = TRUE
)
Arguments
im |
an image. |
style |
numeric (integer). Either 1 (edge-focused) or 2 (smooth gradient) |
weight_levels |
numeric (integer). a vector of lineweight values |
smooth_levels |
numeric (integer). a vector of smooth values |
gain |
a numeric between 0 and 1. Can be used to reduce noise in dim regions. |
contrast |
numeric (integer). Adjusts the image contrast. |
shadow |
a numeric between 0 and 1 |
verbose |
If TRUE (default), progress information is displayed in the Console. |
Value
an array of the sketched image.
Examples
im = survey(face, style = 1, weight_levels = c(1, 3), smooth_levels = c(1, 3), shadow = 0.3)
plot(im)