--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/tesseract/src/ccstruct/dppoint.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,105 @@
+/**********************************************************************
+ * File:        dppoint.h
+ * Description: Simple generic dynamic programming class.
+ * Author:      Ray Smith
+ * Created:     Wed Mar 25 18:57:01 PDT 2009
+ *
+ * (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_CCSTRUCT_DPPOINT_H_
+#define TESSERACT_CCSTRUCT_DPPOINT_H_
+
+#include <cstdint>
+
+namespace tesseract {
+
+// A simple class to provide a dynamic programming solution to a class of
+// 1st-order problems in which the cost is dependent only on the current
+// step and the best cost to that step, with a possible special case
+// of using the variance of the steps, and only the top choice is required.
+// Useful for problems such as finding the optimal cut points in a fixed-pitch
+// (vertical or horizontal) situation.
+// Skeletal Example:
+// DPPoint* array = new DPPoint[width];
+// for (int i = 0; i < width; i++) {
+//   array[i].AddLocalCost(cost_at_i)
+// }
+// DPPoint* best_end = DPPoint::Solve(..., array);
+// while (best_end != nullptr) {
+//   int cut_index = best_end - array;
+//   best_end = best_end->best_prev();
+// }
+// delete [] array;
+class DPPoint {
+public:
+  // The cost function evaluates the total cost at this (excluding this's
+  // local_cost) and if it beats this's total_cost, then
+  // replace the appropriate values in this.
+  using CostFunc = int64_t (DPPoint::*)(const DPPoint *);
+
+  DPPoint()
+      : local_cost_(0)
+      , total_cost_(INT32_MAX)
+      , total_steps_(1)
+      , best_prev_(nullptr)
+      , n_(0)
+      , sig_x_(0)
+      , sig_xsq_(0) {}
+
+  // Solve the dynamic programming problem for the given array of points, with
+  // the given size and cost function.
+  // Steps backwards are limited to being between min_step and max_step
+  // inclusive.
+  // The return value is the tail of the best path.
+  static DPPoint *Solve(int min_step, int max_step, bool debug, CostFunc cost_func, int size,
+                        DPPoint *points);
+
+  // A CostFunc that takes the variance of step into account in the cost.
+  int64_t CostWithVariance(const DPPoint *prev);
+
+  // Accessors.
+  int total_cost() const {
+    return total_cost_;
+  }
+  int Pathlength() const {
+    return total_steps_;
+  }
+  const DPPoint *best_prev() const {
+    return best_prev_;
+  }
+  void AddLocalCost(int new_cost) {
+    local_cost_ += new_cost;
+  }
+
+private:
+  // Code common to different cost functions.
+
+  // Update the other members if the cost is lower.
+  void UpdateIfBetter(int64_t cost, int32_t steps, const DPPoint *prev, int32_t n, int32_t sig_x,
+                      int64_t sig_xsq);
+
+  int32_t local_cost_;       // Cost of this point on its own.
+  int32_t total_cost_;       // Sum of all costs in best path to here.
+                             // During cost calculations local_cost is excluded.
+  int32_t total_steps_;      // Number of steps in best path to here.
+  const DPPoint *best_prev_; // Pointer to prev point in best path from here.
+  // Information for computing the variance part of the cost.
+  int32_t n_;       // Number of steps in best path to here for variance.
+  int32_t sig_x_;   // Sum of step sizes for computing variance.
+  int64_t sig_xsq_; // Sum of squares of steps for computing variance.
+};
+
+} // namespace tesseract.
+
+#endif // TESSERACT_CCSTRUCT_DPPOINT_H_