1 files changed, 140 insertions, 0 deletions
diff --git a/tools/gamma4scanimage.c b/tools/gamma4scanimage.c
new file mode 100644
index 0000000..69d83c7
--- /dev/null
+++ b/tools/gamma4scanimage.c
@@ -0,0 +1,140 @@
+/* --------------------------------------------------------------------------------------------------------- */
+/* sane - Scanner Access Now Easy.
+
+   gamma4scanimage
+
+   (C) 2002 Oliver Rauch
+
+   This file is part of the SANE package.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+   MA 02111-1307, USA.
+
+*/
+/* --------------------------------------------------------------------------------------------------------- */
+
+#include <stdio.h>
+#include <math.h>
+#include <stdlib.h>
+
+int main(int argc, char **argv)
+{
+ double gamma  = 1.0;
+ int maxin     = 16383; /* 14 bit gamma input */
+ int maxout    = 255; /* 8 bit gamma output */
+ int shadow    = 0;
+ int highlight = maxin;
+ int in, out;
+ float f;
+
+  if ( (argc==1) || (argc>6) )
+  {
+    printf("Usage: %s gamma [shadow [highlight [maxin [maxout]]]]\n", argv[0]);
+    exit(-1);
+  }
+
+  if (argc>1)
+  {
+    gamma     = atof(argv[1]);
+  }
+
+  if (argc>2)
+  {
+    shadow    = atoi(argv[2]);
+  }
+
+  if (argc>3)
+  {
+    highlight = atoi(argv[3]);
+  }
+
+  if (argc>4)
+  {
+    maxin     = atoi(argv[4]);
+  }
+
+  if (argc>5)
+  {
+    maxout    = atoi(argv[5]);
+  }
+
+  if (shadow < 0)
+  {
+    printf("%s error: shadow=%d < 0\n", argv[0], shadow);
+    exit(-1);
+  }
+
+  if (highlight < 0)
+  {
+    printf("%s error: highlight=%d < 0\n", argv[0], highlight);
+    exit(-1);
+  }
+
+  if (maxin < 0)
+  {
+    printf("%s error: maxin=%d < 0\n", argv[0], maxin);
+    exit(-1);
+  }
+
+  if (maxout < 0)
+  {
+    printf("%s error: maxout=%d < 0\n", argv[0], maxout);
+    exit(-1);
+  }
+
+  if (shadow >= highlight)
+  {
+    printf("%s error: shadow=%d >= highlight=%d\n", argv[0], shadow, highlight);
+    exit(-1);
+  }
+
+  if (highlight > maxin)
+  {
+    printf("%s error: highlight=%d > maxin=%d\n", argv[0], highlight, maxin);
+    exit(-1);
+  }
+
+  if ((gamma < 0.1) || (gamma > 5))
+  {
+    printf("%s error: gamma=%f out of range [0.1;5]\n", argv[0], gamma);
+    exit(-1);
+  }
+
+  f = (highlight - shadow) / 255.0 + shadow;
+
+  printf("[%d]%d-", 0, 0);
+
+  if (shadow > 0)
+  {
+    printf("[%d]%d-", shadow, 0);
+  }
+
+  while (f < highlight)
+  {
+    in = (int) f;
+    out = maxout * pow((double) (in - shadow)/(highlight-shadow), (1.0/gamma));
+    printf("[%d]%d-", in, out);
+    f *= 1.5;
+  }
+
+  if (f > highlight)
+  {
+    printf("[%d]%d-", highlight, maxout);
+  }
+
+  printf("[%d]%d", maxin, maxout);
+
+ return 0;
+}