--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src_classic/helper-convert.i	Mon Sep 15 11:37:51 2025 +0200
@@ -0,0 +1,98 @@
+%{
+/*
+# ------------------------------------------------------------------------
+# Copyright 2020-2022, Harald Lieder, mailto:harald.lieder@outlook.com
+# License: GNU AFFERO GPL 3.0, https://www.gnu.org/licenses/agpl-3.0.html
+#
+# Part of "PyMuPDF", a Python binding for "MuPDF" (http://mupdf.com), a
+# lightweight PDF, XPS, and E-book viewer, renderer and toolkit which is
+# maintained and developed by Artifex Software, Inc. https://artifex.com.
+# ------------------------------------------------------------------------
+*/
+//-----------------------------------------------------------------------------
+// Convert any MuPDF document to a PDF
+// Returns bytes object containing the PDF, created via 'write' function.
+//-----------------------------------------------------------------------------
+PyObject *JM_convert_to_pdf(fz_context *ctx, fz_document *doc, int fp, int tp, int rotate)
+{
+    pdf_document *pdfout = pdf_create_document(ctx);  // new PDF document
+    int i, incr = 1, s = fp, e = tp;
+    if (fp > tp) {
+        incr = -1;           // count backwards
+        s = tp;              // adjust ...
+        e = fp;              // ... range
+    }
+    fz_rect mediabox;
+    int rot = JM_norm_rotation(rotate);
+    fz_device *dev = NULL;
+    fz_buffer *contents = NULL;
+    pdf_obj *resources = NULL;
+    fz_page *page=NULL;
+    fz_var(dev);
+    fz_var(contents);
+    fz_var(resources);
+    fz_var(page);
+    for (i = fp; INRANGE(i, s, e); i += incr) {  // interpret & write document pages as PDF pages
+        fz_try(ctx) {
+            page = fz_load_page(ctx, doc, i);
+            mediabox = fz_bound_page(ctx, page);
+            dev = pdf_page_write(ctx, pdfout, mediabox, &resources, &contents);
+            fz_run_page(ctx, page, dev, fz_identity, NULL);
+            fz_close_device(ctx, dev);
+            fz_drop_device(ctx, dev);
+            dev = NULL;
+            pdf_obj *page_obj = pdf_add_page(ctx, pdfout, mediabox, rot, resources, contents);
+            pdf_insert_page(ctx, pdfout, -1, page_obj);
+            pdf_drop_obj(ctx, page_obj);
+        }
+        fz_always(ctx) {
+            pdf_drop_obj(ctx, resources);
+            fz_drop_buffer(ctx, contents);
+            fz_drop_device(ctx, dev);
+            fz_drop_page(ctx, page);
+            page = NULL;
+            dev = NULL;
+            contents = NULL;
+            resources = NULL;
+        }
+        fz_catch(ctx) {
+            fz_rethrow(ctx);
+        }
+    }
+    // PDF created - now write it to Python bytearray
+    PyObject *r = NULL;
+    fz_output *out = NULL;
+    fz_buffer *res = NULL;
+    // prepare write options structure
+    pdf_write_options opts = { 0 };
+    opts.do_garbage         = 4;
+    opts.do_compress        = 1;
+    opts.do_compress_images = 1;
+    opts.do_compress_fonts  = 1;
+    opts.do_sanitize        = 1;
+    opts.do_incremental     = 0;
+    opts.do_ascii           = 0;
+    opts.do_decompress      = 0;
+    opts.do_linear          = 0;
+    opts.do_clean           = 1;
+    opts.do_pretty          = 0;
+
+    fz_try(ctx) {
+        res = fz_new_buffer(ctx, 8192);
+        out = fz_new_output_with_buffer(ctx, res);
+        pdf_write_document(ctx, pdfout, out, &opts);
+        unsigned char *c = NULL;
+        size_t len = fz_buffer_storage(ctx, res, &c);
+        r = PyBytes_FromStringAndSize((const char *) c, (Py_ssize_t) len);
+    }
+    fz_always(ctx) {
+        pdf_drop_document(ctx, pdfout);
+        fz_drop_output(ctx, out);
+        fz_drop_buffer(ctx, res);
+    }
+    fz_catch(ctx) {
+        fz_rethrow(ctx);
+    }
+    return r;
+}
+%}