Image Analysis — analysis • magick

Functions for image calculations and analysis. This part of the package needs more work.

image_compare(image, reference_image, metric = "", fuzz = 0)

image_compare_dist(image, reference_image, metric = "", fuzz = 0)

image_fft(image)

Arguments

image: magick image object returned by image_read() or image_graph()
reference_image: another image to compare to
metric: string with a metric from metric_types() such as "AE" or "phash"
fuzz: relative color distance (value between 0 and 100) to be considered similar in the filling algorithm

Details

For details see Image++ documentation. Short descriptions:

image_compare calculates a metric by comparing image with a reference image.
image_fft returns Discrete Fourier Transform (DFT) of the image as a magnitude / phase image pair. I wish I knew what this means.

Here image_compare() is vectorized over the first argument and returns the diff image with the calculated distortion value as an attribute.

See also

Other image: _index_, animation, attributes(), color, composite, defines, device, edges, editing, effects(), fx, geometry, morphology, ocr, options(), painting, segmentation, transform(), video

Examples

out1 <- image_blur(logo, 3)
out2 <- image_oilpaint(logo, 3)
input <- c(logo, out1, out2, logo)
if(magick_config()$version >= "6.8.7"){
  diff_img <- image_compare(input, logo, metric = "AE")
  attributes(diff_img)
}
#> $class
#> [1] "magick-image"
#> 
#> $distortion
#> [1]     0 50455 20580     0
#>