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Get the Diff Image of a Comparison

Source: R/view.R
diff_image.Rd

Read the diff image produced by a comparison.

Usage

diff_image(x, as = c("magick", "raster"))

Arguments

x

An odiff_result from odiff_run(), a one-row data.frame from compare_images(), a single row of an odiffr_batch (e.g. results[2, ]), or the path to a diff image file.

as

Output type: "magick" (default) returns a magick-image (requires the magick package); "raster" returns a raster object (see grDevices::as.raster()) read with png::readPNG(), so magick is not required.

Value

A magick-image or a raster object.

Details

A diff image only exists when the comparison was run with diff_output (or diff_dir for batches) and the images differ. An error is raised otherwise.

See also

plot.odiff_result()

Examples

if (FALSE) { # \dontrun{
result <- compare_images("baseline.png", "current.png", diff_output = TRUE)
img <- diff_image(result)

# Without magick
plot(diff_image(result, as = "raster"))

# One row of a batch
results <- compare_image_dirs("baseline/", "current/", diff_dir = "diffs/")
diff_image(failed_pairs(results)[1, ])
} # }