ImageMagick uses a handy geometry syntax to specify coordinates and shapes for use in image transformations. You can either specify these manually as strings or use the helper functions below.

geometry_point(x, y)

geometry_area(width = NULL, height = NULL, x_off = 0, y_off = 0)

geometry_size_pixels(width = NULL, height = NULL, preserve_aspect = TRUE)

geometry_size_percent(width = 100, height = NULL)

Arguments

x

left offset in pixels

y

top offset in pixels

width

in pixels

height

in pixels

x_off

offset in pixels on x axis

y_off

offset in pixels on y axis

preserve_aspect

if FALSE, resize to width and height exactly, loosing original aspect ratio. Only one of percent and preserve_aspect may be TRUE.

Details

See ImageMagick Manual for details about the syntax specification. Examples of geometry strings:

  • "500x300" -- Resize image keeping aspect ratio, such that width does not exceed 500 and the height does not exceed 300.

  • "500x300!" -- Resize image to 500 by 300, ignoring aspect ratio

  • "500x" -- Resize width to 500 keep aspect ratio

  • "x300" -- Resize height to 300 keep aspect ratio

  • "50%x20%" -- Resize width to 50 percent and height to 20 percent of original

  • "500x300+10+20" -- Crop image to 500 by 300 at position 10,20

See also

Examples

# Specify a point logo <- image_read("logo:") image_annotate(logo, "Some text", location = geometry_point(100, 200), size = 24)
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 640 480 sRGB TRUE 0 72x72
# Specify image area image_crop(logo, geometry_area(300, 300), repage = FALSE)
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 300 300 sRGB FALSE 0 72x72
image_crop(logo, geometry_area(300, 300, 100, 100), repage = FALSE)
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 300 300 sRGB FALSE 0 72x72
# Specify image size image_resize(logo, geometry_size_pixels(300))
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 300 225 sRGB FALSE 0 72x72
image_resize(logo, geometry_size_pixels(height = 300))
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 400 300 sRGB FALSE 0 72x72
image_resize(logo, geometry_size_pixels(300, 300, preserve_aspect = FALSE))
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 300 300 sRGB FALSE 0 72x72
# resize relative to current size image_resize(logo, geometry_size_percent(50))
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 320 240 sRGB FALSE 0 72x72
image_resize(logo, geometry_size_percent(50, 20))
#> # A tibble: 1 x 7 #> format width height colorspace matte filesize density #> <chr> <int> <int> <chr> <lgl> <int> <chr> #> 1 GIF 320 96 sRGB FALSE 0 72x72