--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/tesseract/src/ccutil/qrsequence.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,82 @@
+///////////////////////////////////////////////////////////////////////
+// File:        qrsequence.h
+// Description: Quasi-random sequence generator class.
+// Author:      Ranjith Unnikrishnan
+//
+// Class to generate a (deterministic) quasi-random Van der Corput sequence that
+// covers the interval [0,N) without repetition.
+//
+// The sequence is generated by reversing the base-2 representation of the
+// sequence of natural numbers {0, 1,... M-1}, where M is 2^{num_bits_} and
+// num_bits is the minimum number of bits required to represent N. If a reversed
+// numbers is >= N it is rejected and the next natural number is considered
+// until a valid output number is found.
+//
+// (C) Copyright 2009, Google Inc.
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License.  You may obtain a copy
+// of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required
+// by applicable law or agreed to in writing, software distributed under the
+// License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
+// OF ANY KIND, either express or implied.  See the License for the specific
+// language governing permissions and limitations under the License.
+//
+///////////////////////////////////////////////////////////////////////
+
+#ifndef TESSERACT_CCUTIL_QRSEQUENCE_H_
+#define TESSERACT_CCUTIL_QRSEQUENCE_H_
+
+#include <cmath>
+
+class QRSequenceGenerator {
+public:
+  // Object is initialized with the size of the output range.
+  explicit QRSequenceGenerator(int N) : N_(N), next_num_(0) {
+    num_bits_ = static_cast<int>(ceil(log(static_cast<double>(N)) / log(2.0)));
+  }
+
+  // Main worker method that retrieves the next number in the sequence.
+  // Returns kInvalidVal if called more than N times after object initialization
+  int GetVal() {
+    const int kInvalidVal = -1;
+    const int kMaxNaturalNumberValue = 1 << num_bits_;
+    if (next_num_ >= kMaxNaturalNumberValue) {
+      return kInvalidVal;
+    }
+    int n = next_num_;
+
+    while (next_num_ < kMaxNaturalNumberValue) {
+      n = GetBinaryReversedInteger(next_num_++);
+      if (n < N_) {
+        break;
+      }
+    }
+    return (next_num_ > kMaxNaturalNumberValue) ? kInvalidVal : n;
+  }
+
+protected:
+  // Outputs the integer formed by reversing the bits of the input integer. Only
+  // the lowest num_bits_ bits of the input integer are reversed.
+  int GetBinaryReversedInteger(int in_val) const {
+    int bit_pos = num_bits_;
+    int out_val = 0;
+    while (bit_pos--) {
+      // Set the value of the last bit.
+      out_val |= (in_val & 0x1);
+      if (bit_pos > 0) {
+        // Left-shift output value to prepare for storing the next bit.
+        out_val <<= 1;
+      }
+      // Right-shift input value to prepare for retrieving the next bit.
+      in_val >>= 1;
+    }
+    return out_val;
+  }
+  int N_;
+  // Next number to be considered for reversal and output.
+  int next_num_;
+  // number of bits required to represent the numbers of the sequence
+  int num_bits_;
+};
+
+#endif // TESSERACT_CCUTIL_QRSEQUENCE_H_