Binary package “libtk-img-doc” in ubuntu bionic

Extended image format support for Tcl/Tk (manual pages)

 Img is a package to enhance Tk by providing support for various image
 formats such as XPM, GIF (transparency supported, but not LZW), PNG,
 JPEG, TIFF, and PostScript.
 .
 The libimg library can be loaded dynamically into Tcl/Tk scripts to
 provide the image handling functions.
 .
 This package includes manual pages and examples.