Thank you, Wolfgang.

That looks promising.

SVG files are converted using MetaPost. I thought the following would work:

svg=>{\externalfigure[#1][svg][conversion=mp]}

Is there anything else that needs to happen to ensure SVG files are piped
through MetaPost?

Thanks again!



> \setupexternalfigures [location={local,global,default}]
>
> \defineexternalfigure [jpg] [width=4cm]
> \defineexternalfigure [png] [width=8cm]
>
> \starttexdefinition includegraphics #1
>
>     \splitfilename{#1}
>
>     \processaction
>         [\splitofftype]
>         [    jpg=>{\externalfigure[#1][jpg]},
>              png=>{\externalfigure[#1][png]},
>          default=>{\externalfigure[#1]},
>          unknown=>{\externalfigure[#1]}]
>
> \stoptexdefinition
>
> \starttext
>
> \includegraphics{hacker.jpg}
>
> \includegraphics{mill.png}
>
> \includegraphics{cow.pdf}
>
> \stoptext
>
>