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diff --git a/zbar/qrcode/rs.h b/zbar/qrcode/rs.h
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+/*Copyright (C) 1991-1995  Henry Minsky (hqm@ua.com, hqm@ai.mit.edu)
+  Copyright (C) 2008-2009  Timothy B. Terriberry (tterribe@xiph.org)
+  You can redistribute this library and/or modify it under the terms of the
+   GNU Lesser General Public License as published by the Free Software
+   Foundation; either version 2.1 of the License, or (at your option) any later
+   version.*/
+#if !defined(_qrcode_rs_H)
+#define _qrcode_rs_H (1)
+
+/*This is one of 16 irreducible primitive polynomials of degree 8:
+    x**8+x**4+x**3+x**2+1.
+  Under such a polynomial, x (i.e., 0x02) is a generator of GF(2**8).
+  The high order 1 bit is implicit.
+  From~\cite{MD88}, Ch. 5, p. 275 by Patel.
+  @BOOK{MD88,
+    author="C. Dennis Mee and Eric D. Daniel",
+    title="Video, Audio, and Instrumentation Recording",
+    series="Magnetic Recording",
+    volume=3,
+    publisher="McGraw-Hill Education",
+    address="Columbus, OH",
+    month=Jun,
+    year=1988
+  }*/
+#define QR_PPOLY (0x1D)
+
+/*The index to start the generator polynomial from (0...254).*/
+#define QR_M0 (0)
+
+typedef struct rs_gf256 rs_gf256;
+
+struct rs_gf256 {
+    /*A logarithm table in GF(2**8).*/
+    unsigned char log[256];
+    /*An exponential table in GF(2**8): exp[i] contains x^i reduced modulo the
+     irreducible primitive polynomial used to define the field.
+    The extra 256 entries are used to do arithmetic mod 255, since some extra
+     table lookups are generally faster than doing the modulus.*/
+    unsigned char exp[511];
+};
+
+/*Initialize discrete logarithm tables for GF(2**8) using a given primitive
+   irreducible polynomial.*/
+void rs_gf256_init(rs_gf256 *_gf, unsigned _ppoly);
+
+/*Corrects a codeword with _ndata<256 bytes, of which the last _npar are parity
+   bytes.
+  Known locations of errors can be passed in the _erasures array.
+  Twice as many (up to _npar) errors with a known location can be corrected
+   compared to errors with an unknown location.
+  Returns the number of errors corrected if successful, or a negative number if
+   the message could not be corrected because too many errors were detected.*/
+int rs_correct(const rs_gf256 *_gf, int _m0, unsigned char *_data, int _ndata,
+	       int _npar, const unsigned char *_erasures, int _nerasures);
+
+/*Create an _npar-coefficient generator polynomial for a Reed-Solomon code with
+   _npar<256 parity bytes.*/
+void rs_compute_genpoly(const rs_gf256 *_gf, int _m0, unsigned char *_genpoly,
+			int _npar);
+
+/*Adds _npar<=_ndata parity bytes to an _ndata-_npar byte message.
+  _data must contain room for _ndata<256 bytes.*/
+void rs_encode(const rs_gf256 *_gf, unsigned char *_data, int _ndata,
+	       const unsigned char *_genpoly, int _npar);
+
+#endif