color depth questions

[Maverick2002]

what is 32-bit and 16-bit color?

I know 8-bit = 256 colors
24-bit = 256 colors per each channel in RGB = 16.7 mill

I'm guessing 32-bit is 24-bit + 256 b/w tones? is this right? what is 16?

 

[Heisenberg]

n/m. I need to learn to read.

 

[DaveSimmons]

depends, it is often
(a) really 24-bit just stored in 32-bit chunks to better fit how CPUs access memory
(b) RGBA where A = alpha channel = transparency / opaqueness (for layering)

 

[Maverick2002]

ty

 

[Electric Amish]

I thought that 32-bit is 24 + 8 alpha (like DaveSimmons said)

 

[Maverick2002]

so is 16-bit GIF format with alpha support (8-bit color + 8-bit channel info)?