Display help.
+=item B<--compress>
+
+Compress the output file. This I<only> works if the output format is
+C<qcow2>.
+
=item B<--convert> raw
=item B<--convert> qcow2
Use C<output-format> as the format for the destination image. If this
is not specified, then the input format is used.
-Supported and known-working output formats are: C<raw>, C<qcow2>.
+Supported and known-working output formats are: C<raw>, C<qcow2>, C<vdi>.
You can also use any format supported by the L<qemu-img(1)> program,
-eg. C<vdi> or C<vmdk>, but support for other formats is reliant on
-qemu.
+eg. C<vmdk>, but support for other formats is reliant on qemu.
Specifying the I<--convert> option is usually a good idea, because
then virt-sparsify doesn't need to try to guess the input format.
+For fine-tuning the output format, see: I<--compress>, I<-o>.
+
+=item B<--debug-gc>
+
+Debug garbage collection and memory allocation. This is only useful
+when debugging memory problems in virt-sparsify or the OCaml libguestfs
+bindings.
+
=item B<--format> raw
=item B<--format> qcow2
when being parsed by other programs. See
L</MACHINE READABLE OUTPUT> below.
+=item B<-o> option[,option,...]
+
+Pass I<-o> option(s) to the L<qemu-img(1)> command to fine-tune the
+output format. Options available depend on the output format (see
+I<--convert>) and the installed version of the qemu-img program.
+
+You should use I<-o> at most once. To pass multiple options, separate
+them with commas, eg:
+
+ virt-sparsify --convert qcow2 \
+ -o cluster_size=512,preallocation=metadata ...
+
=item B<-q>
=item B<--quiet>