This function is the same as xfun::base64_uri() (only with a
different function name). It can encode an image file as a base64 string,
which can be used in the img tag in HTML.
uri=image_uri(file.path(R.home("doc"), "html", "logo.jpg"))if(interactive()){cat(sprintf("<img src=\"%s\" />", uri), file ="logo.html")browseURL("logo.html")# you can check its HTML source}