diff --git a/internal/ceres/preprocessor.cc b/internal/ceres/preprocessor.cc
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+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2015 Google Inc. All rights reserved.
+// http://ceres-solver.org/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+// * 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.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+//   used to endorse or promote products derived from this software without
+//   specific prior written permission.
+//
+// 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 THE COPYRIGHT OWNER OR 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.
+//
+// Author: sameragarwal@google.com (Sameer Agarwal)
+
+#include "ceres/callbacks.h"
+#include "ceres/gradient_checking_cost_function.h"
+#include "ceres/line_search_preprocessor.h"
+#include "ceres/parallel_for.h"
+#include "ceres/preprocessor.h"
+#include "ceres/problem_impl.h"
+#include "ceres/solver.h"
+#include "ceres/trust_region_preprocessor.h"
+
+namespace ceres {
+namespace internal {
+
+Preprocessor* Preprocessor::Create(MinimizerType minimizer_type) {
+  if (minimizer_type == TRUST_REGION) {
+    return new TrustRegionPreprocessor;
+  }
+
+  if (minimizer_type == LINE_SEARCH) {
+    return new LineSearchPreprocessor;
+  }
+
+  LOG(FATAL) << "Unknown minimizer_type: " << minimizer_type;
+  return NULL;
+}
+
+Preprocessor::~Preprocessor() {
+}
+
+void ChangeNumThreadsIfNeeded(Solver::Options* options) {
+  const int num_threads_available = MaxNumThreadsAvailable();
+  if (options->num_threads > num_threads_available) {
+    LOG(WARNING)
+        << "Specified options.num_threads: " << options->num_threads
+        << " exceeds maximum available from the threading model Ceres "
+        << "was compiled with: " << num_threads_available
+        << ".  Bounding to maximum number available.";
+    options->num_threads = num_threads_available;
+  }
+}
+
+void SetupCommonMinimizerOptions(PreprocessedProblem* pp) {
+  const Solver::Options& options = pp->options;
+  Program* program = pp->reduced_program.get();
+
+  // Assuming that the parameter blocks in the program have been
+  // reordered as needed, extract them into a contiguous vector.
+  pp->reduced_parameters.resize(program->NumParameters());
+  double* reduced_parameters = pp->reduced_parameters.data();
+  program->ParameterBlocksToStateVector(reduced_parameters);
+
+  Minimizer::Options& minimizer_options = pp->minimizer_options;
+  minimizer_options = Minimizer::Options(options);
+  minimizer_options.evaluator = pp->evaluator;
+
+  if (options.logging_type != SILENT) {
+    pp->logging_callback.reset(
+        new LoggingCallback(options.minimizer_type,
+                            options.minimizer_progress_to_stdout));
+    minimizer_options.callbacks.insert(minimizer_options.callbacks.begin(),
+                                       pp->logging_callback.get());
+  }
+
+  if (options.update_state_every_iteration) {
+    pp->state_updating_callback.reset(
+      new StateUpdatingCallback(program, reduced_parameters));
+    // This must get pushed to the front of the callbacks so that it
+    // is run before any of the user callbacks.
+    minimizer_options.callbacks.insert(minimizer_options.callbacks.begin(),
+                                       pp->state_updating_callback.get());
+  }
+}
+
+}  // namespace internal
+}  // namespace ceres