--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/leptonica/src/partify.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,317 @@
+/*====================================================================*
+ -  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.
+ *====================================================================*/
+
+/*!
+ * \file  partify.c
+ * <pre>
+ *
+ *     Top level
+ *         l_int32          partifyFiles()
+ *         l_int32          partifyPixac()
+ *
+ *     Helpers
+ *         static BOXA     *pixLocateStaveSets()
+ *         static l_int32   boxaRemoveVGaps()
+ * </pre>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config_auto.h>
+#endif  /* HAVE_CONFIG_H */
+
+#include "allheaders.h"
+
+    /* Static helplers */
+static BOXA *pixLocateStaveSets(PIX *pixs, l_int32 pageno, PIXA *pixadb);
+static l_ok boxaRemoveVGaps(BOXA *boxa);
+
+/*---------------------------------------------------------------------*
+ *                              Top level                              *
+ *---------------------------------------------------------------------*/
+/*!
+ * \brief   partifyFiles()
+ *
+ * \param[in]    dirname    directory of files
+ * \param[in]    substr     required filename substring; use NULL for all files
+ * \param[in]    nparts     number of parts to generate (counting from top)
+ * \param[in]    outroot    root name of output pdf files
+ * \param[in]    debugfile  [optional] set to NULL for no debug output
+ * \return  0 if OK, 1 on error
+ *
+ * <pre>
+ * Notes:
+ *      (1) All page images are compressed in png format into a pixacomp.
+ *      (2) Each page image is deskewed, binarized at 300 ppi,
+ *          partified into %nparts, and saved in a set of pixacomps
+ *          in tiff-g4 format.
+ *      (3) Each partified pixacomp is rendered into a set of page images,
+ *          and output as a pdf.
+ * </pre>
+ */
+l_ok
+partifyFiles(const char  *dirname,
+             const char  *substr,
+             l_int32      nparts,
+             const char  *outroot,
+             const char  *debugfile)
+{
+PIXA   *pixadb;
+PIXAC  *pixac;
+
+    if (!dirname)
+        return ERROR_INT("dirname not defined", __func__, 1);
+    if (nparts < 0 || nparts > 10)
+        return ERROR_INT("nparts not in [1 ... 10]", __func__, 1);
+    if (!outroot || outroot[0] == '\n')
+        return ERROR_INT("outroot undefined or empty", __func__, 1);
+
+    pixadb = (debugfile) ? pixaCreate(0) : NULL;
+    pixac = pixacompCreateFromFiles(dirname, substr, IFF_PNG);
+    partifyPixac(pixac, nparts, outroot, pixadb);
+    if (pixadb) {
+        L_INFO("writing debug output to %s\n", __func__, debugfile);
+        pixaConvertToPdf(pixadb, 300, 1.0, L_FLATE_ENCODE, 0,
+                         "Partify Debug", debugfile);
+    }
+    pixacompDestroy(&pixac);
+    pixaDestroy(&pixadb);
+    return 0;
+}
+
+
+/*!
+ * \brief   partifyPixac()
+ *
+ * \param[in]    pixac      with at least one image
+ * \param[in]    nparts     number of parts to generate (counting from top)
+ * \param[in]    outroot    root name of output pdf files
+ * \param[in]    pixadb     [optional] debug pixa; can be NULL
+ * \return  0 if OK, 1 on error
+ *
+ * <pre>
+ * Notes:
+ *      (1) See partifyPixac().
+ *      (2) If the image files do not have a resolution, 300 ppi is assumed.
+ * </pre>
+ */
+l_ok
+partifyPixac(PIXAC       *pixac,
+             l_int32      nparts,
+             const char  *outroot,
+             PIXA        *pixadb)
+{
+char       buf[512];
+l_int32    i, j, pageno, res, npage, nbox, icount, line;
+l_float32  factor;
+L_BMF     *bmf;
+BOX       *box1, *box2;
+BOXA      *boxa1, *boxa2, *boxa3;
+PIX       *pix1, *pix2, *pix3, *pix4, *pix5;
+PIXAC    **pixaca;
+
+    if (!pixac)
+        return ERROR_INT("pixac not defined", __func__, 1);
+    if ((npage = pixacompGetCount(pixac)) == 0)
+        return ERROR_INT("pixac is empty", __func__, 1);
+    if (nparts < 1 || nparts > 10)
+        return ERROR_INT("nparts not in [1 ... 10]", __func__, 1);
+    if (!outroot || outroot[0] == '\n')
+        return ERROR_INT("outroot undefined or empty", __func__, 1);
+
+        /* Initialize the output array for each of the nparts */
+    pixaca = (PIXAC **)LEPT_CALLOC(nparts, sizeof(PIXAC *));
+    for (i = 0; i < nparts; i++)
+        pixaca[i] = pixacompCreate(0);
+
+        /* Process each page */
+    line = 1;
+    bmf = bmfCreate(NULL, 10);
+    for (pageno = 0; pageno < npage; pageno++) {
+        if ((pix1 = pixacompGetPix(pixac, pageno)) == NULL) {
+            L_ERROR("pix for page %d not found\n", __func__, pageno);
+            continue;
+        }
+
+            /* Scale, binarize and deskew */
+        res = pixGetXRes(pix1);
+        if (res == 0 || res == 300 || res > 600) {
+            pix2 = pixClone(pix1);
+        } else {
+            factor = 300.0f / (l_float32)res;
+            if (factor > 3)
+                L_WARNING("resolution is very low\n", __func__);
+            pix2 = pixScale(pix1, factor, factor);
+        }
+        pix3 = pixConvertTo1Adaptive(pix2);
+        pix4 = pixDeskew(pix3, 0);
+        pixDestroy(&pix1);
+        pixDestroy(&pix2);
+        pixDestroy(&pix3);
+        if (!pix4) {
+            L_ERROR("pix for page %d not deskewed\n", __func__, pageno);
+            continue;
+        }
+        pix1 = pixClone(pix4);  /* rename */
+        pixDestroy(&pix4);
+
+            /* Find the stave sets at 4x reduction */
+        boxa1 = pixLocateStaveSets(pix1, pageno, pixadb);
+
+            /* Break each stave set into the separate staves (parts).
+             * A typical set will have more than one part, but if one of
+             * the parts is a keyboard, it will usually have two staves
+             * (also called a Grand Staff), composed of treble and
+             * bass staves.  For example, a classical violin sonata
+             * could have a staff for the violin and two staves for
+             * the piano.  We would set nparts == 2, and extract both
+             * of the piano staves as the piano part.  */
+        nbox = boxaGetCount(boxa1);
+        lept_stderr("number of boxes in page %d: %d\n", pageno, nbox);
+        for (i = 0; i < nbox; i++, line++) {
+            snprintf(buf, sizeof(buf), "%d", line);
+            box1 = boxaGetBox(boxa1, i, L_COPY);
+            pix2 = pixClipRectangle(pix1, box1, NULL);
+            pix3 = pixMorphSequence(pix2, "d1.20 + o50.1 + o1.30", 0);
+            boxa2 = pixConnCompBB(pix3, 8);
+            boxa3 = boxaSort(boxa2, L_SORT_BY_Y, L_SORT_INCREASING, NULL);
+            boxaRemoveVGaps(boxa3);
+            icount = boxaGetCount(boxa3);
+            if (icount < nparts)
+                L_WARNING("nparts requested = %d, but only found %d\n",
+                          __func__, nparts, icount);
+            for (j = 0; j < icount && j < nparts; j++) {
+                box2 = boxaGetBox(boxa3, j, L_COPY);
+                if (j == nparts - 1)  /* extend the box to the bottom */
+                    boxSetSideLocations(box2, -1, -1, -1,
+                                        pixGetHeight(pix1) - 1);
+                pix4 = pixClipRectangle(pix2, box2, NULL);
+                pix5 = pixAddTextlines(pix4, bmf, buf, 1, L_ADD_LEFT);
+                pixacompAddPix(pixaca[j], pix5, IFF_TIFF_G4);
+                boxDestroy(&box2);
+                pixDestroy(&pix4);
+                pixDestroy(&pix5);
+            }
+            boxaDestroy(&boxa2);
+            boxaDestroy(&boxa3);
+            boxDestroy(&box1);
+            pixDestroy(&pix2);
+            pixDestroy(&pix3);
+        }
+        boxaDestroy(&boxa1);
+        pixDestroy(&pix1);
+    }
+
+        /* Output separate pdfs for each part */
+    for (i = 0; i < nparts; i++) {
+        snprintf(buf, sizeof(buf), "%s-%d.pdf", outroot, i);
+        L_INFO("writing part %d: %s\n", __func__, i, buf);
+        pixacompConvertToPdf(pixaca[i], 300, 1.0, L_G4_ENCODE, 0, NULL, buf);
+        pixacompDestroy(&pixaca[i]);
+    }
+    LEPT_FREE(pixaca);
+    bmfDestroy(&bmf);
+    return 0;
+}
+
+
+/*
+ * \brief   pixLocateStaveSets()
+ *
+ * \param[in]    pixs       1 bpp, 300 ppi, deskewed
+ * \param[in]    pageno     page number; used for debug output
+ * \param[in]    pixadb     [optional] debug pixa; can be NULL
+ * \return   boxa   containing the stave sets at full resolution
+ */
+static BOXA *
+pixLocateStaveSets(PIX     *pixs,
+                   l_int32  pageno,
+                   PIXA    *pixadb)
+{
+BOXA  *boxa1, *boxa2, *boxa3, *boxa4;
+PIX   *pix1, *pix2;
+
+    if (!pixs)
+        return (BOXA *)ERROR_PTR("pixs not defined", __func__, NULL);
+
+        /* Find the stave sets at 4x reduction */
+    pix1 = pixMorphSequence(pixs, "r11", 0);
+    boxa1 = pixConnCompBB(pix1, 8);
+    boxa2 = boxaSelectByArea(boxa1, 15000, L_SELECT_IF_GT, NULL);
+    boxa3 = boxaSort(boxa2, L_SORT_BY_Y, L_SORT_INCREASING, NULL);
+    if (pixadb) {
+        pix2 = pixConvertTo32(pix1);
+        pixRenderBoxaArb(pix2, boxa3, 2, 255, 0, 0);
+        pixaAddPix(pixadb, pix2, L_INSERT);
+        pixDisplay(pix2, 100 * pageno, 100);
+    }
+    boxaDestroy(&boxa1);
+    boxaDestroy(&boxa2);
+
+    boxaRemoveVGaps(boxa3);
+    if (pixadb) {
+        pix2 = pixConvertTo32(pix1);
+        pixRenderBoxaArb(pix2, boxa3, 2, 0, 255, 0);
+        pixaAddPix(pixadb, pix2, L_INSERT);
+        pixDisplay(pix2, 100 * pageno, 600);
+    }
+    boxa4 = boxaTransform(boxa3, 0, 0, 4.0, 4.0);  /* back to full res */
+    boxaDestroy(&boxa3);
+    pixDestroy(&pix1);
+    return boxa4;
+}
+
+
+/*
+ * \brief   boxaRemoveVGaps()
+ *
+ * \param[in]    boxa
+ * \return   0 if OK, 1 on error
+ *
+ * <pre>
+ * Notes:
+ *      (1) The boxes in %boxa are aligned vertically.  Move the horizontal
+ *          edges vertically to remove the gaps between boxes.
+ * </pre>
+ */
+static  l_ok
+boxaRemoveVGaps(BOXA  *boxa)
+{
+l_int32  nbox, i, y1, h1, y2, h2, delta;
+
+    if (!boxa)
+        return ERROR_INT("boxa not defined", __func__, 1);
+    if ((nbox = boxaGetCount(boxa)) == 0)
+        return ERROR_INT("boxa is empty", __func__, 1);
+    for (i = 0; i < nbox - 1; i++) {
+        boxaGetBoxGeometry(boxa, i, NULL, &y1, NULL, &h1);
+        boxaGetBoxGeometry(boxa, i + 1, NULL, &y2, NULL, &h2);
+        delta = (y2 - y1 - h1) / 2;
+        boxaAdjustBoxSides(boxa, i, 0, 0, 0, delta);
+        boxaAdjustBoxSides(boxa, i + 1, 0, 0, -delta, 0);
+    }
+    boxaAdjustBoxSides(boxa, nbox - 1, 0, 0, 0, delta);  /* bot of last */
+    return 0;
+}