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PPMTOLSS16(1) General Commands Manual PPMTOLSS16(1)

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.