magick (version 0.1)

transformations: Image Transformations

Description

Vectorized functions for transforming images. These functions apply the same transformation to each frame in the image. The Magick++ documentation explains meaning of each function and parameter. See editing for functions to read or combine image sequences.

Usage

image_trim(image)
image_background(image, color)
image_crop(image, geometry = "")
image_scale(image, geometry = "")
image_sample(image, geometry = "")
image_border(image, color = "", geometry = "")
image_noise(image, noisetype = "gaussian")
image_blur(image, radius = 1, sigma = 0.5)
image_charcoal(image, radius = 1, sigma = 0.5)
image_edge(image, radius = 1)
image_oilpaint(image, radius = 1)
image_emboss(image, radius = 1, sigma = 0.5)
image_enhance(image)
image_equalize(image)
image_flip(image)
image_flop(image)
image_frame(image, geometry = "25x25+6+6")
image_implode(image, factor = 0.5)
image_negate(image)
image_normalize(image)
image_rotate(image, degrees)
image_fill(image, color, point = "1x1", fuzz = 0)
image_chop(image, geometry)
image_colorize(image, opacity, color)
image_composite(image, composite_image = image[1], operator = "atop", offset = "0x0")
image_contrast(image, sharpen = 1)
image_annotate(image, text, gravity = "northwest", location = "+0+0", degrees = 0, size = 10, font = NULL, color = NULL, strokecolor = NULL, boxcolor = NULL)
image_convert(image, format)

Arguments

image

object returned by image_read

color

a valid color string

geometry

a string with geometry syntax for example "10x10+5-5".

noisetype

integer betwee 0 and 5 with noisetype.

radius

the radius of the Gaussian, in pixels, not counting the center pixel.

sigma

the standard deviation of the Laplacian, in pixels.

factor

image implode factor (special effect)

degrees

how many degrees

point

string indicating the flood-fill starting point

fuzz

Colors within this distance are considered equal. Use this option to match colors that are close to the target color in RGB space. I think max distance (from #000000 to #FFFFFF) is 256^3.

opacity

percentage of transparency

composite_image

composition image

operator

string with a composite operator.

offset

geometry string with offset

sharpen

enhance intensity differences in image

text

annotation text

gravity

string with gravity type

location

geometry string with location relative to gravity

size

font-size in pixels

font

rendering font. To use a TrueType font, precede the TrueType filename with an @.

strokecolor

adds a stroke (border around the text)

boxcolor

background color that annotation text is rendered on.

format

output format such as png, jpeg, gif or pdf.

Details

Each function returns a copy of the manipulated image; the input image will be unaffected. Therefore operations can be piped with magrittr if you're into that kind of stuff.

See Also

Other image: editing

Examples

logo <- image_read(system.file("Rlogo.png", package = "magick"))
logo <- image_scale(logo, "400")
image_trim(logo)
image_crop(logo, "400x400+200+200")
image_scale(logo, "200x200")
image_sample(logo, "200x200")
image_border(logo, "red", "10x10")
image_noise(logo)
image_blur(logo, 10, 10)
image_charcoal(logo)
image_edge(logo)
image_oilpaint(logo)
image_emboss(logo)
image_enhance(logo)
image_equalize(logo)
image_flip(logo)
image_flop(logo)
image_frame(logo)
image_implode(logo)
image_negate(logo)
image_normalize(logo)
image_rotate(logo, 45)
image_fill(logo, "red")
image_fill(logo, "red", fuzz = 256^2)
image_chop(logo, "100x20")
image_colorize(logo, 50, "red")
# Compose images using one of many operators
oldlogo <- image_read(system.file("Rlogo-old.png", package = "magick"))
image_composite(logo, oldlogo)
image_composite(logo, oldlogo, operator = "copyred")

# Lights up the R logo
frames <- image_scale(oldlogo, "400x400")
for(i in 1:7) frames <- c(frames, image_contrast(frames[i]))
(blink <- image_animate(c(frames, rev(frames)), fps = 20, loop = 1))

# Add some text to an image
image_annotate(logo, "This is a test")
image_annotate(logo, "CONFIDENTIAL", size = 50, color = "red", boxcolor = "pink",
 degrees = 30, location = "+100+100")

# Setting fonts requires fontconfig support (and that you have the font)
myfont <- ifelse(identical("windows", .Platform$OS.type), "courier-new", "courier")
image_annotate(logo, "The quick brown fox", font = myfont, size = 50)