Portable Pixmap
<file format> (PPM) A colour image file format.
A PPM file contains the following:
a two character "{magic number}" - "P3",
the width in pixels,
the height in pixels,
the maximum colour component value,
HEIGHT rows of WIDTH {pixels}.
The rows are ordered from top to bottom with the pixels in each row
ordered from left to right. Each pixel is
represented as three values for red, green, and
blue.
All parts are separated by whitespace and numbers are in decimal ASCIII
representation. A zero pixel component means that colour is absent. Characters
from a "#" to the next end-of-line are ignored and no line should be longer than
70 characters.
Here is an example of a small pixmap in this format:
P3
# feep.ppm
4 4
15
0 0 0 0 0 0 0 0 0 15 0 15
0 0 0 0 15 7 0 0 0 0 0 0
0 0 0 0 0 0 0 15 7 0 0 0
15 0 15 0 0 0 0 0 0 0 0 0
A "RAWBITS" variant has magic number "P6", pixel values are stored as
plain binary bytes, instead of ASCII decimal and no
whitespace is allowed after a single whitespace
character after the maximum colour component value
which must be less than or equal to 255.
(1998-02-06)
Nearby terms:
Portable Network Graphics « Portable Object Adapter
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