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

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 50045 20580 0 #>