--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/leptonica/src/convertfiles.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,147 @@
+/*====================================================================*
+ -  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 convertfiles.c
+ * <pre>
+ *
+ *      Conversion to 1 bpp
+ *          l_int32    convertFilesTo1bpp()
+ *
+ *  These are utility functions that will perform depth conversion
+ *  on selected files, writing the results to a specified directory.
+ *  We start with conversion to 1 bpp.
+ * </pre>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config_auto.h>
+#endif  /* HAVE_CONFIG_H */
+
+#include <string.h>
+#include "allheaders.h"
+
+/*------------------------------------------------------------------*
+ *                        Conversion to 1 bpp                       *
+ *------------------------------------------------------------------*/
+/*!
+ * \brief   convertFilesTo1bpp()
+ *
+ * \param[in]    dirin
+ * \param[in]    substr       [optional] substring filter on filenames;
+ 8                            can be NULL
+ * \param[in]    upscaling    1, 2 or 4; only for input color or grayscale
+ * \param[in]    thresh       global threshold for binarization; 0 for default
+ * \param[in]    firstpage
+ * \param[in]    npages       use 0 to do all from %firstpage to the end
+ * \param[in]    dirout
+ * \param[in]    outformat    IFF_PNG, IFF_TIFF_G4
+ * \return  0 if OK, 1 on error
+ *
+ * <pre>
+ * Notes:
+ *      (1) Images are sorted lexicographically, and the names in the
+ *          output directory are retained except for the extension.
+ * </pre>
+ */
+l_ok
+convertFilesTo1bpp(const char  *dirin,
+                   const char  *substr,
+                   l_int32      upscaling,
+                   l_int32      thresh,
+                   l_int32      firstpage,
+                   l_int32      npages,
+                   const char  *dirout,
+                   l_int32      outformat)
+{
+l_int32  i, nfiles;
+char     buf[512];
+char    *fname, *tail, *basename;
+PIX     *pixs, *pixg1, *pixg2, *pixb;
+SARRAY  *safiles;
+
+    if (!dirin)
+        return ERROR_INT("dirin", __func__, 1);
+    if (!dirout)
+        return ERROR_INT("dirout", __func__, 1);
+    if (upscaling != 1 && upscaling != 2 && upscaling != 4)
+        return ERROR_INT("invalid upscaling factor", __func__, 1);
+    if (thresh <= 0) thresh = 180;
+    if (firstpage < 0) firstpage = 0;
+    if (npages < 0) npages = 0;
+    if (outformat != IFF_TIFF_G4)
+        outformat = IFF_PNG;
+
+    safiles = getSortedPathnamesInDirectory(dirin, substr, firstpage, npages);
+    if (!safiles)
+        return ERROR_INT("safiles not made", __func__, 1);
+    if ((nfiles = sarrayGetCount(safiles)) == 0) {
+        sarrayDestroy(&safiles);
+        return ERROR_INT("no matching files in the directory", __func__, 1);
+    }
+
+    for (i = 0; i < nfiles; i++) {
+        fname = sarrayGetString(safiles, i, L_NOCOPY);
+        if ((pixs = pixRead(fname)) == NULL) {
+            L_WARNING("Couldn't read file %s\n", __func__, fname);
+            continue;
+        }
+        if (pixGetDepth(pixs) == 32)
+            pixg1 = pixConvertRGBToLuminance(pixs);
+        else
+            pixg1 = pixClone(pixs);
+        pixg2 = pixRemoveColormap(pixg1, REMOVE_CMAP_TO_GRAYSCALE);
+        if (pixGetDepth(pixg2) == 1) {
+            pixb = pixClone(pixg2);
+        } else {
+            if (upscaling == 1)
+                pixb = pixThresholdToBinary(pixg2, thresh);
+            else if (upscaling == 2)
+                pixb = pixScaleGray2xLIThresh(pixg2, thresh);
+            else  /* upscaling == 4 */
+                pixb = pixScaleGray4xLIThresh(pixg2, thresh);
+        }
+        pixDestroy(&pixs);
+        pixDestroy(&pixg1);
+        pixDestroy(&pixg2);
+
+        splitPathAtDirectory(fname, NULL, &tail);
+        splitPathAtExtension(tail, &basename, NULL);
+        if (outformat == IFF_TIFF_G4) {
+            snprintf(buf, sizeof(buf), "%s/%s.tif", dirout, basename);
+            pixWrite(buf, pixb, IFF_TIFF_G4);
+        } else {
+            snprintf(buf, sizeof(buf), "%s/%s.png", dirout, basename);
+            pixWrite(buf, pixb, IFF_PNG);
+        }
+        pixDestroy(&pixb);
+        LEPT_FREE(tail);
+        LEPT_FREE(basename);
+    }
+
+    sarrayDestroy(&safiles);
+    return 0;
+}