On 12/2/06, Lars Aronsson <lars(a)aronsson.se> wrote:
For example, the image
http://runeberg.org/img/nfad/0670.4.png is
240 kbytes in 150 dpi 16-level grayscale PNG but only 200 kbytes
in 600 dpi bitonal TIFF G4. The difference between 150 dpi
grayscale and 600 dpi bitonal becomes very clear when you try to
print the page on a 600 or 1200 dpi laser printer.
Well, you should compare apples to apples. The image you specified
becames only 58 kbytes wen saved as 1-bit (bitonal) PNG. And bitmapped
formats like PNG and TIFF have no concept of "dpi"- that's an external
manipulation made by the printing program. You need to compare images
with the same pixel sizes.
Ciao,
Alfio