PosteRazor is an open source to make poster,runs on Linux.
The PosteRazor cuts a raster image into pieces which can afterwards be printed out and assembled to a poster.

As input, the PosteRazor takes a raster image. The resulting poster is saved as a multipage PDF document. An easy to use, wizard like user interface guides through 5 steps. It is an open source.

Features:
Input image formats
All image formats that FreeImage can read should be usable as input for the PosteRazor:
BMP, DDS, Dr. Halo, GIF, ICO, IFF, JBIG, JPEG/JIF, KOALA, LBM, Kodak PhotoCD, PCX, PBM, PGM, PNG, PPM, PhotoShop PSD, Sun RAS, TARGA, TIFF, WBMP, XBM, XPM

Image types
PosteRazor can handle the following image color types:
Monochrome, Grayscale, 4 Bit palette, 8 Bit palette, 24 Bit RGB, 48 Bit RGB (only via TIFF and PNG), 32 Bit CMYK (only via TIFF)
32 Bit RGBA images can be loaded, but are transformed to 24 Bit RGB by merging them with a white background.

Dimension Units
Because people around the world invented so many different dimension units, PosteRazor supports quite a few:
m, mm, cm, inch, ft, pt(72th inch)

Printer page layout
The page size and orientation of the printer where the poster will be printed can be set manually or selected one from the following list of predefined formats:
DIN A4, DIN A3, Legal, Letter, Tabloid you can free download PosteRazor for Linux 1.5 now.