[XeTeX] How does xetex handle non-native image filessuchas eps?

[Yuan Qi]

Ulrike Fischer <news2 at ...> writes:

> if the conversion command can convert it to a native image format.
> 
> What conversion command? If you are using a "native" format, that is one
> for which xetex has a library, no conversion is involved. Then xetex can
> simply open it, get the size and continue with the page setting. 
> 
> Also \DeclareGraphicsRule isn't a command that requires something. It is
> command that informs latex or xelatex or pdflatex how and if a certain
> format can be handled. 

The conversion command I was referring to is the fourth argument of  
\DeclareGraphicsRule. On example would be {'pstopdf #1}