1 files changed, 102 insertions, 0 deletions
diff --git a/leptonica/prog/extrema_reg.c b/leptonica/prog/extrema_reg.c
new file mode 100644
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+++ b/leptonica/prog/extrema_reg.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.
+ *====================================================================*/
+
+/*
+ *  extrema_reg.c
+ *
+ *     Tests procedure for locating extrema (minima and maxima)
+ *     of a sampled function.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config_auto.h>
+#endif  /* HAVE_CONFIG_H */
+
+#include <math.h>
+#include "allheaders.h"
+
+int main(int    argc,
+         char **argv)
+{
+l_uint8      *data;
+size_t        size;
+l_int32       i, ival, n;
+l_float32     f, val;
+GPLOT        *gplot;
+NUMA         *na1, *na2, *na3;
+PIX          *pix1;
+L_REGPARAMS  *rp;
+
+#if !defined(HAVE_LIBPNG)
+    L_ERROR("This test requires libpng to run.\n", "extrema_reg");
+    exit(77);
+#endif
+
+    if (regTestSetup(argc, argv, &rp))
+        return 1;
+
+    lept_mkdir("lept/extrema");
+
+        /* Generate a 1D signal and plot it */
+    na1 = numaCreate(500);
+    for (i = 0; i < 500; i++) {
+        f = 48.3 * sin(0.13 * (l_float32)i);
+        f += 63.4 * cos(0.21 * (l_float32)i);
+        numaAddNumber(na1, f);
+    }
+    gplot = gplotCreate("/tmp/lept/extrema/plot", GPLOT_PNG,
+                        "Extrema test", "x", "y");
+    gplotAddPlot(gplot, NULL, na1, GPLOT_LINES, "plot 1");
+
+        /* Find the local min and max and plot them */
+    na2 = numaFindExtrema(na1, 38.3, NULL);
+    n = numaGetCount(na2);
+    na3 = numaCreate(n);
+    for (i = 0; i < n; i++) {
+        numaGetIValue(na2, i, &ival);
+        numaGetFValue(na1, ival, &val);
+        numaAddNumber(na3, val);
+    }
+    gplotAddPlot(gplot, na2, na3, GPLOT_POINTS, "plot 2");
+    gplotMakeOutput(gplot);
+
+    numaWriteMem(&data, &size, na2);
+    regTestWriteDataAndCheck(rp, data, size, "na");  /* 0 */
+    lept_free(data);
+
+    regTestCheckFile(rp, "/tmp/lept/extrema/plot.png");  /* 1 */
+    if (rp->display) {
+        pix1 = pixRead("/tmp/lept/extrema/plot.png");
+        pixDisplay(pix1, 100, 100);
+        pixDestroy(&pix1);
+    }
+
+    gplotDestroy(&gplot);
+    numaDestroy(&na1);
+    numaDestroy(&na2);
+    numaDestroy(&na3);
+    return regTestCleanup(rp);
+}