[linguaz]

If the psb format can be converted to ppm format (via ImageMagick?), and image size is the issue, maybe NASA's BigView could be an option:

BigView allows for interactive panning and zooming of images of arbitrary size on desktop PCs running linux. Additionally, it can work in a multi-screen environment where multiple PCs cooperate to view a single large image. Using this software, one can explore -- on relatively modest machines -- images such as the Mars Orbiter Camera mosaic [92160x33280 pixels].

http://ti.arc.nasa.gov/opensource/projects/bigview/