diff --git a/internal/ceres/CMakeLists.txt b/internal/ceres/CMakeLists.txt
index 1dd4090..18ff92b 100644
--- a/internal/ceres/CMakeLists.txt
+++ b/internal/ceres/CMakeLists.txt
@@ -43,6 +43,7 @@
     c_api.cc
     canonical_views_clustering.cc
     cgnr_solver.cc
+    callbacks.cc
     compressed_col_sparse_matrix_utils.cc
     compressed_row_jacobian_writer.cc
     compressed_row_sparse_matrix.cc
diff --git a/internal/ceres/callbacks.cc b/internal/ceres/callbacks.cc
new file mode 100644
index 0000000..c551162
--- /dev/null
+++ b/internal/ceres/callbacks.cc
@@ -0,0 +1,107 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2014 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// 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: sameeragarwal@google.com (Sameer Agarwal)
+
+#include <iostream>  // NO LINT
+#include "ceres/callbacks.h"
+#include "ceres/program.h"
+#include "ceres/stringprintf.h"
+#include "glog/logging.h"
+
+namespace ceres {
+namespace internal {
+
+StateUpdatingCallback::StateUpdatingCallback(Program* program,
+                                             double* parameters)
+    : program_(program), parameters_(parameters) {}
+
+StateUpdatingCallback::~StateUpdatingCallback() {}
+
+CallbackReturnType StateUpdatingCallback::operator()(
+    const IterationSummary& summary) {
+  if (summary.step_is_successful) {
+    program_->StateVectorToParameterBlocks(parameters_);
+    program_->CopyParameterBlockStateToUserState();
+  }
+  return SOLVER_CONTINUE;
+}
+
+LoggingCallback::LoggingCallback(const MinimizerType minimizer_type,
+                                 const bool log_to_stdout)
+    : minimizer_type(minimizer_type),
+      log_to_stdout_(log_to_stdout) {}
+
+LoggingCallback::~LoggingCallback() {}
+
+CallbackReturnType LoggingCallback::operator()(
+    const IterationSummary& summary) {
+  string output;
+  if (minimizer_type == LINE_SEARCH) {
+    const char* kReportRowFormat =
+        "% 4d: f:% 8e d:% 3.2e g:% 3.2e h:% 3.2e "
+        "s:% 3.2e e:% 3d it:% 3.2e tt:% 3.2e";
+    output = StringPrintf(kReportRowFormat,
+                          summary.iteration,
+                          summary.cost,
+                          summary.cost_change,
+                          summary.gradient_max_norm,
+                          summary.step_norm,
+                          summary.step_size,
+                          summary.line_search_function_evaluations,
+                          summary.iteration_time_in_seconds,
+                          summary.cumulative_time_in_seconds);
+  } else if (minimizer_type == TRUST_REGION) {
+    const char* kReportRowFormat =
+        "% 4d: f:% 8e d:% 3.2e g:% 3.2e h:% 3.2e "
+        "rho:% 3.2e mu:% 3.2e li:% 3d it:% 3.2e tt:% 3.2e";
+    output = StringPrintf(kReportRowFormat,
+                          summary.iteration,
+                          summary.cost,
+                          summary.cost_change,
+                          summary.gradient_max_norm,
+                          summary.step_norm,
+                          summary.relative_decrease,
+                          summary.trust_region_radius,
+                          summary.linear_solver_iterations,
+                          summary.iteration_time_in_seconds,
+                          summary.cumulative_time_in_seconds);
+  } else {
+    LOG(FATAL) << "Unknown minimizer type.";
+  }
+
+  if (log_to_stdout_) {
+    cout << output << endl;
+  } else {
+    VLOG(1) << output;
+  }
+  return SOLVER_CONTINUE;
+}
+
+}  // namespace internal
+}  // namespace ceres
diff --git a/internal/ceres/callbacks.h b/internal/ceres/callbacks.h
new file mode 100644
index 0000000..93704df
--- /dev/null
+++ b/internal/ceres/callbacks.h
@@ -0,0 +1,71 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2014 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// 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: sameeragarwal@google.com (Sameer Agarwal)
+
+#ifndef CERES_INTERNAL_CALLBACKS_H_
+#define CERES_INTERNAL_CALLBACKS_H_
+
+#include <string>
+#include "ceres/iteration_callback.h"
+#include "ceres/internal/port.h"
+
+namespace ceres {
+namespace internal {
+
+class Program;
+
+// Callback for updating the externally visible state of parameter
+// blocks.
+class StateUpdatingCallback : public IterationCallback {
+ public:
+  StateUpdatingCallback(Program* program, double* parameters);
+  virtual ~StateUpdatingCallback();
+  virtual CallbackReturnType operator()(const IterationSummary& summary);
+ private:
+  Program* program_;
+  double* parameters_;
+};
+
+// Callback for logging the state of the minimizer to STDERR or
+// STDOUT depending on the user's preferences and logging level.
+class LoggingCallback : public IterationCallback {
+ public:
+  LoggingCallback(MinimizerType minimizer_type, bool log_to_stdout);
+  virtual ~LoggingCallback();
+  virtual CallbackReturnType operator()(const IterationSummary& summary);
+
+ private:
+  const MinimizerType minimizer_type;
+  const bool log_to_stdout_;
+};
+
+}  // namespace internal
+}  // namespace ceres
+
+#endif  // CERES_INTERNAL_CALLBACKS_H_
diff --git a/internal/ceres/solver_impl.cc b/internal/ceres/solver_impl.cc
index 8148716..101439c 100644
--- a/internal/ceres/solver_impl.cc
+++ b/internal/ceres/solver_impl.cc
@@ -35,6 +35,7 @@
 #include <numeric>
 #include <string>
 #include "ceres/array_utils.h"
+#include "ceres/callbacks.h"
 #include "ceres/coordinate_descent_minimizer.h"
 #include "ceres/cxsparse.h"
 #include "ceres/evaluator.h"
@@ -61,26 +62,6 @@
 namespace internal {
 namespace {
 
-// Callback for updating the user's parameter blocks. Updates are only
-// done if the step is successful.
-class StateUpdatingCallback : public IterationCallback {
- public:
-  StateUpdatingCallback(Program* program, double* parameters)
-      : program_(program), parameters_(parameters) {}
-
-  CallbackReturnType operator()(const IterationSummary& summary) {
-    if (summary.step_is_successful) {
-      program_->StateVectorToParameterBlocks(parameters_);
-      program_->CopyParameterBlockStateToUserState();
-    }
-    return SOLVER_CONTINUE;
-  }
-
- private:
-  Program* program_;
-  double* parameters_;
-};
-
 void SetSummaryFinalCost(Solver::Summary* summary) {
   summary->final_cost = summary->initial_cost;
   // We need the loop here, instead of just looking at the last
@@ -91,106 +72,6 @@
   }
 }
 
-// Callback for logging the state of the minimizer to STDERR or STDOUT
-// depending on the user's preferences and logging level.
-class TrustRegionLoggingCallback : public IterationCallback {
- public:
-  explicit TrustRegionLoggingCallback(bool log_to_stdout)
-      : log_to_stdout_(log_to_stdout) {}
-
-  ~TrustRegionLoggingCallback() {}
-
-  CallbackReturnType operator()(const IterationSummary& summary) {
-    const char* kReportRowFormat =
-        "% 4d: f:% 8e d:% 3.2e g:% 3.2e h:% 3.2e "
-        "rho:% 3.2e mu:% 3.2e li:% 3d it:% 3.2e tt:% 3.2e";
-    string output = StringPrintf(kReportRowFormat,
-                                 summary.iteration,
-                                 summary.cost,
-                                 summary.cost_change,
-                                 summary.gradient_max_norm,
-                                 summary.step_norm,
-                                 summary.relative_decrease,
-                                 summary.trust_region_radius,
-                                 summary.linear_solver_iterations,
-                                 summary.iteration_time_in_seconds,
-                                 summary.cumulative_time_in_seconds);
-    if (log_to_stdout_) {
-      cout << output << endl;
-    } else {
-      VLOG(1) << output;
-    }
-    return SOLVER_CONTINUE;
-  }
-
- private:
-  const bool log_to_stdout_;
-};
-
-// Callback for logging the state of the minimizer to STDERR or STDOUT
-// depending on the user's preferences and logging level.
-class LineSearchLoggingCallback : public IterationCallback {
- public:
-  explicit LineSearchLoggingCallback(bool log_to_stdout)
-      : log_to_stdout_(log_to_stdout) {}
-
-  ~LineSearchLoggingCallback() {}
-
-  CallbackReturnType operator()(const IterationSummary& summary) {
-    const char* kReportRowFormat =
-        "% 4d: f:% 8e d:% 3.2e g:% 3.2e h:% 3.2e "
-        "s:% 3.2e e:% 3d it:% 3.2e tt:% 3.2e";
-    string output = StringPrintf(kReportRowFormat,
-                                 summary.iteration,
-                                 summary.cost,
-                                 summary.cost_change,
-                                 summary.gradient_max_norm,
-                                 summary.step_norm,
-                                 summary.step_size,
-                                 summary.line_search_function_evaluations,
-                                 summary.iteration_time_in_seconds,
-                                 summary.cumulative_time_in_seconds);
-    if (log_to_stdout_) {
-      cout << output << endl;
-    } else {
-      VLOG(1) << output;
-    }
-    return SOLVER_CONTINUE;
-  }
-
- private:
-  const bool log_to_stdout_;
-};
-
-
-// Basic callback to record the execution of the solver to a file for
-// offline analysis.
-class FileLoggingCallback : public IterationCallback {
- public:
-  explicit FileLoggingCallback(const string& filename)
-      : fptr_(NULL) {
-    fptr_ = fopen(filename.c_str(), "w");
-    CHECK_NOTNULL(fptr_);
-  }
-
-  virtual ~FileLoggingCallback() {
-    if (fptr_ != NULL) {
-      fclose(fptr_);
-    }
-  }
-
-  virtual CallbackReturnType operator()(const IterationSummary& summary) {
-    fprintf(fptr_,
-            "%4d %e %e\n",
-            summary.iteration,
-            summary.cost,
-            summary.cumulative_time_in_seconds);
-    return SOLVER_CONTINUE;
-  }
- private:
-    FILE* fptr_;
-};
-
 // Iterate over each of the groups in order of their priority and fill
 // summary with their sizes.
 void SummarizeOrdering(ParameterBlockOrdering* ordering,
@@ -422,8 +303,8 @@
   // vector.
   program->ParameterBlocksToStateVector(parameters.data());
 
-  TrustRegionLoggingCallback logging_callback(
-      options.minimizer_progress_to_stdout);
+  LoggingCallback logging_callback(TRUST_REGION,
+                                   options.minimizer_progress_to_stdout);
   if (options.logging_type != SILENT) {
     minimizer_options.callbacks.insert(minimizer_options.callbacks.begin(),
                                        &logging_callback);
@@ -487,8 +368,8 @@
   // Collect the discontiguous parameters into a contiguous state vector.
   program->ParameterBlocksToStateVector(parameters.data());
 
-  LineSearchLoggingCallback logging_callback(
-      options.minimizer_progress_to_stdout);
+  LoggingCallback logging_callback(LINE_SEARCH,
+                                   options.minimizer_progress_to_stdout);
   if (options.logging_type != SILENT) {
     minimizer_options.callbacks.insert(minimizer_options.callbacks.begin(),
                                        &logging_callback);