Ubuntu: Convert psd files with imagemagick
Source: http://superuser.com/questions/360434/any-way-to-save-all-psd-layers-separately
Imagemagick will by default convert a psd to multiple images:
convert file.psd file.png
will result in file-0.png, file-1.png etc for each layer. If you wanted a single image, use the flatten switch:
convert file.psd -flatten file.png
Imagemagick is available on osx, windows and linux. And iOS somehow.