Tutorial - Color of main image and cell images.

Please think about it:
Photos are our ink, and the main image is what we are going to draw.

First of all, Let look at this color table.
It is a standard 8 bit color table. there are 6×6x6=216 colors in this table.

If you look a photo at distance, it will appers as a single color.
This is the basic theory of mosaic technology.

By calculate more than 1,000,000 photos, we have a result here:
Most photos appear as the following colors:
You can see, most photos cant be placed to pure color area.

It means, If your main image contains too many pure color, for example, black or white, It will be very hard to find a photo for the cells. and the final quality cann’t be good.

In another word, The cell images is another importand factor.
For example, If you take many photos in a forest, most photos will be placed to green area or close to green area.
Then you can not use it to create a red crab photomosaic.