[libvirt] building failed

[Wen Congyang]

When I try to build libvirt, I meet the following error messages:
==============================
Generating internals/rpc.html.tmp
Validating internals/rpc.html
  GEN    libvirt-api.xml
  GEN    html/index.html
  GEN    devhelp/libvirt.devhelp
convert -rotate 90 libvirt-net-logical.fig libvirt-net-logical.png
make[1]: convert: Command not found
make[1]: *** [libvirt-net-logical.png] Error 127
==============================

The command convert does not exist. Which package should I install?

PS: I find another command fig2dev can convert *.fig to *.png.

Thanks
Wen Congyang