--- netpbm-10.25/converter/ppm/ppmtobmp.c.bmpbpp	2004-03-13 20:37:32.000000000 +0100

+++ netpbm-10.25/converter/ppm/ppmtobmp.c	2004-10-18 12:23:43.762552192 +0200

@@ -509,6 +509,25 @@ analyze_colors(const pixel **    const p

     } else {

         *minimum_bpp_p = pm_maxvaltobits(*colors_p-1);

         pm_message("%d colors found", *colors_p);

+	

+	{

+	    int bpps[] = {1,4,8,24,0};

+	    int i;

+	    

+	    for (i = 0; bpps[i] && bpps[i] != *minimum_bpp_p; i++);

+	    

+	    if (!bpps[i]) {

+		for (i = 0; bpps[i]; i++)

+		    if (*colors_p-1 < (1<<bpps[i])) break;

+		    

+		/*

+		 * If the *minimum_bpp_p is > 24 bpp leave it as is

+		 */    

+		if (bpps[i])

+		    *minimum_bpp_p = bpps[i];

+	    }

+	}

+	

         /*

          * Now scale the maxval to 255 as required by BMP format.

          */