NAME
ppmtolss16 — Convert a PPM to an LSS16 image
SYNOPSIS
ppmtolss16 [ #rrggbb=i ...] [< input.ppm] [>
output.rle]
DESCRIPTION
This manual page documents briefly the ppmtolss16 command.
The ppmtolss16 program converts a "raw" PPM file with max 16 colors to
a simple RLE-based format:
simple RLE-based format
unint32 0x1413f3d magic (littleendian)
unint16 xsize littleendian
unint15 ysize littleendian
16 x unint8 r,g,b color map
Color map is in 6-bit format (each byte is 0..63)
Then, a sequence of nybbles:
N ... if N is != previous pixel, one pixel of color N, otherwise run
sequence follows ...
M ... if M > 0 then run length is M+1, otherwise run sequence is
encoded in two nybbles, littleendian, +17
The nybble sequences are on a per-row basis, runs may not extend across
rows and odd-nybble rows are zero-padded.
At the start of a row, the "previous pixel" is assumed to be zero.
OPTIONS
A summary of options is included below.
#rrggbb=i Specify that the color #rrggbb (hex) should be assigned index
i (decimal).
BUG
This program cannot handle comments in the header, nor "plain" ppm
format.
SEE ALSO
ppmtolss16(1)
AUTHOR
This manual page was compiled by dann frazier <dannf@debian.org> for
the Debian GNU/Linux system (but may be used by others). Most of the
content was written by H. Peter Anvin.