1 files changed, 116 insertions, 0 deletions
diff --git a/leptonica/prog/comparepages.c b/leptonica/prog/comparepages.c
new file mode 100644
index 00000000..45437356
--- /dev/null
+++ b/leptonica/prog/comparepages.c
@@ -0,0 +1,116 @@
+/*====================================================================*
+ -  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.
+ *====================================================================*/
+
+/*
+ * comparepages.c
+ *
+ *    This compares text pages using the location of word bounding boxes.
+ *    The goal is to get a fast and robust determination for whether
+ *    two pages are the same.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config_auto.h>
+#endif  /* HAVE_CONFIG_H */
+
+#include "allheaders.h"
+
+int main(int    argc,
+         char **argv)
+{
+l_int32  w, h, n, same;
+BOXA    *boxa1, *boxa2;
+NUMA    *nai1, *nai2;
+NUMAA   *naa1, *naa2;
+PIX     *pixs, *pixt, *pixb1, *pixb2;
+
+    setLeptDebugOK(1);
+    lept_mkdir("lept/comp");
+
+    pixs = pixRead("lucasta.047.jpg");
+    pixb1 = pixConvertTo1(pixs, 128);
+    pixGetWordBoxesInTextlines(pixb1, 10, 10, 500, 50, &boxa1, &nai1);
+    pixt = pixDrawBoxaRandom(pixs, boxa1, 2);
+    pixDisplay(pixt, 100, 100);
+    pixWrite("/tmp/lept/comp/pixt.png", pixt, IFF_PNG);
+    naa1 = boxaExtractSortedPattern(boxa1, nai1);
+    numaaWrite("/tmp/lept/comp/naa1.naa", naa1);
+    n = numaaGetCount(naa1);
+    lept_stderr("Number of textlines = %d\n", n);
+    pixDisplay(pixb1, 300, 0);
+
+        /* Translate */
+    pixb2 = pixCreateTemplate(pixb1);
+    pixGetDimensions(pixb1, &w, &h, NULL);
+    pixRasterop(pixb2, 148, 133, w, h, PIX_SRC, pixb1, 0, 0);
+    pixDisplay(pixb2, 600, 0);
+    pixGetWordBoxesInTextlines(pixb2, 10, 10, 500, 50, &boxa2, &nai2);
+    naa2 = boxaExtractSortedPattern(boxa2, nai2);
+    numaaCompareImagesByBoxes(naa1, naa2, 5, 10, 150, 150, 20, 20, &same, 1);
+    lept_stderr("Translation.  same?: %d\n\n", same);
+    boxaDestroy(&boxa2);
+    numaDestroy(&nai2);
+    pixDestroy(&pixb2);
+    numaaDestroy(&naa2);
+
+        /* Aligned part is below h/3 */
+    pixb2 = pixCreateTemplate(pixb1);
+    pixGetDimensions(pixb1, &w, &h, NULL);
+    pixRasterop(pixb2, 0, 0, w, h / 3, PIX_SRC, pixb1, 0, 2 * h / 3);
+    pixRasterop(pixb2, 0, h / 3, w, 2 * h / 3, PIX_SRC, pixb1, 0, h / 3);
+    pixDisplay(pixb2, 900, 0);
+    pixGetWordBoxesInTextlines(pixb2, 10, 10, 500, 50, &boxa2, &nai2);
+    naa2 = boxaExtractSortedPattern(boxa2, nai2);
+    numaaCompareImagesByBoxes(naa1, naa2, 5, 10, 150, 150, 20, 20, &same, 1);
+    lept_stderr("Aligned part below h/3.  same?: %d\n\n", same);
+    boxaDestroy(&boxa2);
+    numaDestroy(&nai2);
+    pixDestroy(&pixb2);
+    numaaDestroy(&naa2);
+
+        /* Top and bottom switched; no aligned parts */
+    pixb2 = pixCreateTemplate(pixb1);
+    pixGetDimensions(pixb1, &w, &h, NULL);
+    pixRasterop(pixb2, 0, 0, w, h / 3, PIX_SRC, pixb1, 0, 2 * h / 3);
+    pixRasterop(pixb2, 0, h / 3, w, 2 * h / 3, PIX_SRC, pixb1, 0, 0);
+    pixDisplay(pixb2, 1200, 0);
+    pixGetWordBoxesInTextlines(pixb2, 10, 10, 500, 50, &boxa2, &nai2);
+    naa2 = boxaExtractSortedPattern(boxa2, nai2);
+    numaaCompareImagesByBoxes(naa1, naa2, 5, 10, 150, 150, 20, 20, &same, 1);
+    lept_stderr("Top/Bot switched; no alignment.  Same?: %d\n", same);
+    boxaDestroy(&boxa2);
+    numaDestroy(&nai2);
+    pixDestroy(&pixb2);
+    numaaDestroy(&naa2);
+
+    boxaDestroy(&boxa1);
+    numaDestroy(&nai1);
+    pixDestroy(&pixs);
+    pixDestroy(&pixb1);
+    pixDestroy(&pixt);
+    numaaDestroy(&naa1);
+    return 0;
+}