If you have 2 files of the same size and the first is made up of 1000s of colors

Question

and the second is made up of only 6 colors, why doesn't it take longer to create 1000s of colors, and thus longer to download, compared to a 6-color file? "Two files of the same size take the same time to download" is not an answer to this question - it is for that earlier question I asked.

Thanks for the help !

Answer 1

A picture has no flat dimensions as you might imagine.

Let's take a picture of 10x10 pixels. You would guess that to pictures of 10x10 pixels are the same size. But there is a slight problem.

Every pixel should be able to display it's correct color.

Let's simplify it a bit.

Let's say your picture can display 1 color

the dimensions would be 10x10x1=100

If it could display 2 colors it would be 10x10x2=200

for 8 colors 10x10x8 e=800 etc.

See it as a kind of layers. In reality it's a bit more complicated. Every pixel is a kind of container that can hold a certain amount of values by setting certain bits to 1 or 0.

lets say you want 16 colors, then you need 4 bits.

every bit can be either on or of so have 16 possibilitys.

for 256 colors you need 8 bits 2^8=256

for 1000nds of colors 16 bit 2^16=65536 etc.

But after all there are two things to consuider

1) The amount of data you sent. In that case it's really true same size is about the same time.

2) Which kind of compression is used and how much overhead does this give to the receiving computer. A JPG must be uncompressed befoore it can be viewed, a GIF can be compressed, but doesn't have to be. besides that it's compression algorithm isn't as complex as the jpg.

So it can take longer depending on several circumstances