Create Subversion repository

git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@1 9d0c8265-081b-0410-96cb-a4ca84ce46f8

1 files changed, 120 insertions, 0 deletions

diff --git a/converter/ppm/ppmtopi1.c b/converter/ppm/ppmtopi1.c
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+++ b/converter/ppm/ppmtopi1.c
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+/* ppmtopi1.c - read a portable pixmap and write a Degas PI1 file
+**
+** Copyright (C) 1991 by Steve Belczyk and Jef Poskanzer.
+**
+** Permission to use, copy, modify, and distribute this software and its
+** documentation for any purpose and without fee is hereby granted, provided
+** that the above copyright notice appear in all copies and that both that
+** copyright notice and this permission notice appear in supporting
+** documentation.  This software is provided "as is" without express or
+** implied warranty.
+*/
+
+#include "ppm.h"
+
+#define COLS 320
+#define ROWS 200
+#define MAXVAL 7
+#define MAXCOLORS 16
+
+static short screen[ROWS*COLS/4];  /* simulate the ST's video RAM */
+
+int
+main( argc, argv )
+    int argc;
+    char* argv[];
+    {
+    FILE* ifp;
+    pixel** pixels;
+    register pixel *pP;
+    colorhist_vector chv;
+    colorhash_table cht;
+    int rows, cols, row, colors, i;
+    register int col;
+    pixval maxval;
+
+
+    ppm_init( &argc, argv );
+
+    if ( argc > 2 )
+        pm_usage( "[ppmfile]" );
+
+    if ( argc == 2 )
+        ifp = pm_openr( argv[1] );
+    else
+        ifp = stdin;
+
+    pixels = ppm_readppm( ifp, &cols, &rows, &maxval );
+    pm_close( ifp );
+    if ( (cols > COLS) || (rows > ROWS) )
+        pm_error( "image is larger than %dx%d - sorry", COLS, ROWS );
+
+    pm_message( "computing colormap..." );
+    chv = ppm_computecolorhist( pixels, cols, rows, MAXCOLORS, &colors );
+    if ( chv == (colorhist_vector) 0 )
+        {
+        pm_message(
+            "too many colors - try doing a 'pnmquant %d'", MAXCOLORS );
+        exit( 1 );
+        }
+    pm_message( "%d colors found", colors );
+
+    /* Write PI1 header - resolution and palette. */
+    (void) pm_writebigshort( stdout, (short) 0 );       /* low resolution */
+    for ( i = 0; i < 16; ++i )
+        {
+        short w;
+
+        if ( i < colors )
+            {
+            pixel p;
+
+            p = chv[i].color;
+            if ( maxval != MAXVAL )
+                PPM_DEPTH( p, p, maxval, MAXVAL );
+            w  = ( (int) PPM_GETR( p ) ) << 8;
+            w |= ( (int) PPM_GETG( p ) ) << 4;
+            w |= ( (int) PPM_GETB( p ) );
+            }
+        else
+            w = 0;
+        (void) pm_writebigshort( stdout, w );
+        }
+    if ( maxval > MAXVAL )
+        pm_message(
+            "maxval is not %d - automatically rescaling colors", MAXVAL );
+
+    /* Convert color vector to color hash table, for fast lookup. */
+    cht = ppm_colorhisttocolorhash( chv, colors );
+    ppm_freecolorhist( chv );
+
+    /* Clear the screen buffer. */
+    for ( i = 0; i < ROWS*COLS/4; ++i )
+        screen[i] = 0;
+
+    /* Convert. */
+    for ( row = 0; row < rows; ++row )
+        {
+        for ( col = 0, pP = pixels[row]; col < cols; ++col, ++pP )
+            {
+            register int color, ind, b, plane;
+
+            color = ppm_lookupcolor( cht, pP );
+            if ( color == -1 )
+                pm_error(
+                    "color not found?!?  row=%d col=%d  r=%d g=%d b=%d",
+                    row, col, PPM_GETR(*pP), PPM_GETG(*pP), PPM_GETB(*pP) );
+            ind = 80 * row + ( ( col >> 4 ) << 2 );
+            b = 0x8000 >> (col & 0xf);
+            for ( plane = 0; plane < 4; ++plane )
+                if ( color & (1 << plane) )
+                    screen[ind+plane] |= b;
+            }
+        }
+
+    /* And write out the screen buffer. */
+    for ( i = 0; i < ROWS*COLS/4; ++i )
+        (void) pm_writebigshort( stdout, screen[i] );
+
+    exit( 0 );
+    }