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.TH "PPMTOLSS16" "1"
ppmtolss16 \(em Convert a PPM to an LSS16 image
\fBppmtolss16\fR [ \fB \fI#rrggbb\fR=\fIi\fR \fP \&...] [< input.ppm] [> output.rle]
This manual page documents briefly the \fBppmtolss16\fR command.
The \fBppmtolss16\fR program converts a "raw" PPM file with
max 16 colors to a simple RLE-based format:
\fBsimple RLE-based format\fR
l l.
unint32 0x1413f3dmagic (littleendian)
unint16 xsizelittleendian
unint15 ysizelittleendian
16 x unint8 r,g,bcolor 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.
A summary of options is included below.
.IP "\fB\fI#rrggbb\fR=\fIi\fR\fP" 10
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 <> for
the \fBDebian GNU/Linux\fP system (but may be used by others). Most of the content
was written by H. Peter Anvin.