1PPMTOLSS16(1) General Commands Manual PPMTOLSS16(1)
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6 ppmtolss16 — Convert a PPM to an LSS16 image
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9 ppmtolss16 [ #rrggbb=i ...] [< input.ppm] [>
10 output.rle]
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13 This manual page documents briefly the ppmtolss16 command.
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16 The ppmtolss16 program converts a "raw" PPM file with max 16 colors to
17 a simple RLE-based format:
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20 simple RLE-based format
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22 unint32 0x1413f3d magic (littleendian)
23 unint16 xsize littleendian
24 unint15 ysize littleendian
25 16 x unint8 r,g,b color map
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27 Color map is in 6-bit format (each byte is 0..63)
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29 Then, a sequence of nybbles:
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31 N ... if N is != previous pixel, one pixel of color N, otherwise run
32 sequence follows ...
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35 M ... if M > 0 then run length is M+1, otherwise run sequence is
36 encoded in two nybbles, littleendian, +17
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39 The nybble sequences are on a per-row basis, runs may not extend across
40 rows and odd-nybble rows are zero-padded.
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43 At the start of a row, the "previous pixel" is assumed to be zero.
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47 A summary of options is included below.
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49 #rrggbb=i Specify that the color #rrggbb (hex) should be assigned index
50 i (decimal).
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54 This program cannot handle comments in the header, nor "plain" ppm for‐
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59 ppmtolss16(1)
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63 This manual page was compiled by dann frazier <dannf@debian.org> for
64 the Debian GNU/Linux system (but may be used by others). Most of the
65 content was written by H. Peter Anvin.
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69 PPMTOLSS16(1)