Scan mode (stand alone)
The scan mode is to scan an image and save it to a file.
You can select the output format by the filename extension (menu = "by ext") or by selecting the file format in the menu. Possible are: pnm, png, ps, jpeg, raw and tiff.
Pnm and ps (and raw) are always available. The other formats are only available if necessary libraries are present (at compilation time AND while xsane is executed). For png you need libpng and libz, for jpeg you need jpeglib, for tiff you need libtiff.
The raw format is a 16 bit format comparable to 16 bit binary pnm format that is not defined, for pnm the 16 bit format only is defined as ascii mode which generates huge and slow files.
The supported output formats depend on the bit depth of the scanned image:1 bit/pixel black/white mode:
pnm = pbm, png
ps, jpeg and tiff are converted to 8 bit grayscale mode.8 bits/pixel grayscale mode:
pnm = pgm, png, ps, jpeg and tiff16 bits/pixel grayscale mode (9-16 bits):
pnm (ascii), png and raw24 bits/pixel RGB-color mode (8 bits/color):
pnm = ppm, png, ps, jpeg and tiff48 bits/pixel RGB-color mode (9-16 bits/color):
pnm (ascii), png and raw32 bits/pixel RGBA-color mode (8 bits/color):
rgba (raw) and png with alpha channel64 bits/pixel RGBA-color mode (9-16 bits/color):
rgba (raw) and png with alpha channel