We can flexibly add a local image (i.e., an image residing on disk) inside of a table with local_image() function. The function provides a convenient way to generate an HTML fragment using an on-disk PNG or SVG. Because this function is currently HTML-based, it is only useful for HTML table output. To use this function inside of data cells, it is recommended that the text_transform() function is used. With that function, we can specify which data cells to target and then include a local_image() call within the required user-defined function (for the fn argument). If we want to include an image in other places (e.g., in the header, within footnote text, etc.) we need to use local_image() within the html() helper function.

local_image(file, height = 30)

Arguments

file

a path to an image file.

height

the absolute height (px) of the image in the table cell.

Value

a character object with an HTML fragment that can be placed inside of a cell.

Details

By itself, the function creates an HTML image tag with an image URI embedded within. We can easily experiment with a local PNG or SVG image that's available in the gt package using the test_image() function. Using that, the call local_image(file = test_image(type = "png")) evaluates to:

<img cid=<random CID> src=<data URI> style=\"height:30px;\">

where a height of 30px is a default height chosen to work well within the heights of most table rows.

Figures

See also

Other image addition functions: ggplot_image, test_image, web_image

Examples

# Create a tibble that contains heights # of an image in pixels (one column as a # string, the other as numerical values), # then, create a gt table; use the # `text_transform()` function to insert # a local test image (PNG) image with the # various sizes tab_1 <- dplyr::tibble( pixels = px(seq(10, 35, 5)), image = seq(10, 35, 5) ) %>% gt() %>% text_transform( locations = cells_data(vars(image)), fn = function(x) { local_image( file = test_image(type = "png"), height = as.numeric(x) ) } )