Bit Depth
| Bit Depth (bits per pixel) |
Number of colours or tones |
| 1 |
2 |
| 2 |
4 |
| 3 |
8 |
| 4 |
16 |
| 6 |
64 |
| 8 |
256 |
| 16 |
65,536 |
| 24 (3 x 8 ) |
16,777,216 |
| 32 |
4,294,967,296 |
Colour Lookup Tables (LUTs) give you a choice of more colours
One stores only the index to a set of colours chosen amongst a
larger set
E.g. : 16 bit pictures, choosing amongst millions of colours
instead of thousands
a 300x200 image could anyway need up to 60,000 colours!