Making Pictures with Data

That’s the colour of a capital “A” in a grayscale image, as explained below:

The file “demo1” contains exactly 36 x 50, or 1800 single-byte characters, or 1800 bytes. I can break up the vertical lines by choosing another frame size adding up to 1800 pixels, for example 45×40:

I can do this in colour, too, but this time IM will use a different byte for each RGB channel. Note the “A[blank]p” colour in the leftmost column:

Here’s a prettier version, with the pre-scale-up frame set to 40×15 pixels:

IM will return an error message unless the number of data bytes it’s given is in agreement with the number of pixels.

Source: www.datafix.com.au