http://www.tcl.tk/man/tcl8.4/TkCmd/photo.htm

A photo [image] is the means that Tk uses to display full color images.
Tk comes with support for GIF, PPM, and PGM formats, as well as a format to hook in code for other formats. The [Img] extension provides additional full color image formats.

[Photo image rotation] - [Image scaling]
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