Import Ghostscript 9.54ghostscript-9.54

Signed-off-by: Thomas Deutschmann <whissi@gentoo.org>

1 files changed, 129 insertions, 0 deletions

diff --git a/leptonica/prog/otsutest2.c b/leptonica/prog/otsutest2.c
new file mode 100644
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+++ b/leptonica/prog/otsutest2.c
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+/*====================================================================*
+ -  Copyright (C) 2001 Leptonica.  All rights reserved.
+ -
+ -  Redistribution and use in source and binary forms, with or without
+ -  modification, are permitted provided that the following conditions
+ -  are met:
+ -  1. Redistributions of source code must retain the above copyright
+ -     notice, this list of conditions and the following disclaimer.
+ -  2. Redistributions in binary form must reproduce the above
+ -     copyright notice, this list of conditions and the following
+ -     disclaimer in the documentation and/or other materials
+ -     provided with the distribution.
+ -
+ -  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ -  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ -  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ -  A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL ANY
+ -  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ -  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ -  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ -  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ -  OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ -  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ -  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *====================================================================*/
+
+/*
+ *   otsutest2.c
+ *
+ *   This demonstrates the usefulness of the modified version of Otsu
+ *   for thresholding an image that doesn't have a well-defined
+ *   background color.
+ *
+ *   Standard Otsu binarization is done with scorefract = 0.0, which
+ *   returns the threshold at the maximum value of the score.  However.
+ *   this value is up on the shoulder of the background, and its
+ *   use causes some of the dark background to be binarized as foreground.
+ *
+ *   Using the modified Otsu with scorefract = 0.1 returns a threshold
+ *   at the lowest value of this histogram such that the score
+ *   is at least 0.9 times the maximum value of the score.  This allows
+ *   the threshold to be taken in the histogram minimum between
+ *   the fg and bg peaks, producing a much cleaner binarization.
+ */
+
+
+#ifdef HAVE_CONFIG_H
+#include <config_auto.h>
+#endif  /* HAVE_CONFIG_H */
+
+#include "allheaders.h"
+
+
+int main(int    argc,
+         char **argv)
+{
+char       textstr[256];
+l_int32    i, thresh, fgval, bgval;
+l_float32  scorefract;
+L_BMF     *bmf;
+PIX       *pixs, *pixb, *pixg, *pixp, *pix1, *pix2, *pix3;
+PIXA      *pixa1, *pixad;
+
+    setLeptDebugOK(1);
+    lept_mkdir("lept/otsu");
+
+    pixs = pixRead("1555.007.jpg");
+    pixg = pixConvertTo8(pixs, 0);
+    bmf = bmfCreate(NULL, 8);
+    pixad = pixaCreate(0);
+    for (i = 0; i < 3; i++) {
+        pixa1 = pixaCreate(2);
+        scorefract = 0.1 * i;
+
+            /* Get a 1 bpp version; use a single tile */
+        pixOtsuAdaptiveThreshold(pixg, 2000, 2000, 0, 0, scorefract,
+                                 NULL, &pixb);
+        pixaAddPix(pixa1, pixg, L_COPY);
+        pixaAddPix(pixa1, pixb, L_INSERT);
+
+            /* Show the histogram of gray values and the split location */
+        pixSplitDistributionFgBg(pixg, scorefract, 1,
+                                 &thresh, &fgval, &bgval, &pixp);
+        lept_stderr("thresh = %d, fgval = %d, bgval = %d\n",
+                    thresh, fgval, bgval);
+        pixaAddPix(pixa1, pixp, L_INSERT);
+
+            /* Join these together and add some text */
+        pix1 = pixaDisplayTiledInColumns(pixa1, 3, 1.0, 20, 2);
+        snprintf(textstr, sizeof(textstr),
+             "Scorefract = %3.1f ........... Thresh = %d", scorefract, thresh);
+        pix2 = pixAddSingleTextblock(pix1, bmf, textstr, 0x00ff0000,
+                                     L_ADD_BELOW, NULL);
+
+            /* Save and display the result */
+        pixaAddPix(pixad, pix2, L_INSERT);
+        snprintf(textstr, sizeof(textstr), "/tmp/lept/otsu/%03d.png", i);
+        pixWrite(textstr, pix2, IFF_PNG);
+        pixDisplay(pix2, 100, 100);
+        pixDestroy(&pix1);
+        pixaDestroy(&pixa1);
+    }
+
+        /* Use a smaller tile for Otsu */
+    for (i = 0; i < 2; i++) {
+        scorefract = 0.1 * i;
+        pixOtsuAdaptiveThreshold(pixg, 300, 300, 0, 0, scorefract,
+                                 NULL, &pixb);
+        pix1 = pixAddBlackOrWhiteBorder(pixb, 2, 2, 2, 2, L_GET_BLACK_VAL);
+        pix2 = pixScale(pix1, 0.5, 0.5);
+        snprintf(textstr, sizeof(textstr),
+             "Scorefract = %3.1f", scorefract);
+        pix3 = pixAddSingleTextblock(pix2, bmf, textstr, 1,
+                                     L_ADD_BELOW, NULL);
+        pixaAddPix(pixad, pix3, L_INSERT);
+        pixDestroy(&pixb);
+        pixDestroy(&pix1);
+        pixDestroy(&pix2);
+    }
+
+    lept_stderr("Writing to: /tmp/lept/otsu/result1.pdf\n");
+    pixaConvertToPdf(pixad, 75, 1.0, 0, 0, "Otsu thresholding",
+                     "/tmp/lept/otsu/result1.pdf");
+    bmfDestroy(&bmf);
+    pixDestroy(&pixs);
+    pixDestroy(&pixg);
+    pixaDestroy(&pixad);
+    return 0;
+}