These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.01 s (backtrack: 0/20).

[ebuild  N     ] media-libs/libpano13-2.9.23:0/3::gentoo  USE="-java -static-libs -suitesparse" 2789 KiB
[ebuild  N     ] media-gfx/autopano-sift-C-2.5.1-r2::gentoo  188 KiB

Total: 2 packages (2 new), Size of downloads: 2976 KiB