| 1 | .TH "PPMTOLSS16" "1" |
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| 2 | .SH "NAME" |
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| 3 | ppmtolss16 \(em Convert a PPM to an LSS16 image |
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| 4 | .SH "SYNOPSIS" |
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| 5 | .PP |
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| 6 | \fBppmtolss16\fR [ \fB \fI#rrggbb\fR=\fIi\fR \fP \&...] [< input.ppm] [> output.rle] |
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| 7 | .SH "DESCRIPTION" |
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| 8 | .PP |
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| 9 | This manual page documents briefly the \fBppmtolss16\fR command. |
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| 10 | |
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| 11 | .PP |
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| 12 | The \fBppmtolss16\fR program converts a "raw" PPM file with |
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| 13 | max 16 colors to a simple RLE-based format: |
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| 14 | |
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| 15 | .PP |
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| 16 | \fBsimple RLE-based format\fR |
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| 17 | .TS |
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| 18 | tab(); |
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| 19 | l l. |
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| 20 | unint32 0x1413f3dmagic (littleendian) |
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| 21 | unint16 xsizelittleendian |
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| 22 | unint15 ysizelittleendian |
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| 23 | 16 x unint8 r,g,bcolor map |
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| 24 | .TE |
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| 25 | .PP |
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| 26 | Color map is in 6-bit format (each byte is 0..63) |
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| 27 | .PP |
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| 28 | Then, a sequence of nybbles: |
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| 29 | .PP |
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| 30 | N ... if N is != previous pixel, one pixel of color N, otherwise |
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| 31 | run sequence follows ... |
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| 32 | |
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| 33 | .PP |
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| 34 | M ... if M > 0 then run length is M+1, otherwise run sequence is |
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| 35 | encoded in two nybbles, littleendian, +17 |
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| 36 | |
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| 37 | .PP |
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| 38 | The nybble sequences are on a per-row basis, runs may not extend across |
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| 39 | rows and odd-nybble rows are zero-padded. |
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| 40 | |
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| 41 | .PP |
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| 42 | At the start of a row, the "previous pixel" is assumed to be zero. |
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| 43 | |
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| 44 | .SH "OPTIONS" |
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| 45 | .PP |
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| 46 | A summary of options is included below. |
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| 47 | .IP "\fB\fI#rrggbb\fR=\fIi\fR\fP" 10 |
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| 48 | Specify that the color #rrggbb (hex) should be assigned index |
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| 49 | i (decimal). |
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| 50 | |
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| 51 | .SH "BUG" |
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| 52 | .PP |
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| 53 | This program cannot handle comments in the header, nor "plain" ppm |
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| 54 | format. |
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| 55 | |
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| 56 | .SH "SEE ALSO" |
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| 57 | .PP |
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| 58 | \fBppmtolss16\fR(1) |
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| 59 | |
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| 60 | .SH "AUTHOR" |
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| 61 | .PP |
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| 62 | This manual page was compiled by dann frazier <dannf@debian.org> for |
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| 63 | the \fBDebian GNU/Linux\fP system (but may be used by others). Most of the content |
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| 64 | was written by H. Peter Anvin. |
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