ppmtolss16 — Convert a PPM to an LSS16 image
=i ...] [< input.ppm]
This manual page documents briefly the ppmtolss16
program converts a "raw" PPM file with max 16
colors to a simple RLE-based format:
simple RLE-based format
|16 x unint8 r,g,b
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
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.
A summary of options is included below.
- Specify that the color #rrggbb (hex) should be assigned index i (decimal).
This program cannot handle comments in the header, nor "plain" ppm
This manual page was compiled by dann frazier <email@example.com> for the
system (but may be used by others). Most of the
content was written by H. Peter Anvin.