Visualization tool for WebrtcEventLogs

webrtc/tools/event_log_visualizer/plot_python.cc

Index: webrtc/tools/event_log_visualizer/plot_python.cc
diff --git a/webrtc/tools/event_log_visualizer/plot_python.cc b/webrtc/tools/event_log_visualizer/plot_python.cc
new file mode 100644
index 0000000000000000000000000000000000000000..916bc2e6a61451359e1e3cff6b746ac6d98d7b53
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+++ b/webrtc/tools/event_log_visualizer/plot_python.cc
@@ -0,0 +1,98 @@
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/tools/event_log_visualizer/plot_python.h"
+
+#include <stdio.h>
+
+namespace webrtc {
+namespace plotting {
+
+PythonPlot::PythonPlot() {}
+
+PythonPlot::~PythonPlot() {}
+
+void PythonPlot::draw() {
+  // Write python commands to stdout. Intended program usage is
+  // ./event_log_visualizer event_log160330.dump | python
+
+  if (!series.empty()) {
+    printf("color_count = %zu\n", series.size());
+    printf(
+        "hls_colors = [(i*1.0/color_count, 0.25+i*0.5/color_count, 0.8) for i "
+        "in range(color_count)]\n");
+    printf("rgb_colors = [colorsys.hls_to_rgb(*hls) for hls in hls_colors]\n");
+
+    for (size_t i = 0; i < series.size(); i++) {
+      // List x coordinates
+      printf("x%zu = [", i);
+      if (series[i].points.size() > 0)
+        printf("%G", series[i].points[0].x);
+      for (size_t j = 1; j < series[i].points.size(); j++)
+        printf(", %G", series[i].points[j].x);
+      printf("]\n");
+
+      // List y coordinates
+      printf("y%zu = [", i);
+      if (series[i].points.size() > 0)
+        printf("%G", series[i].points[0].y);
+      for (size_t j = 1; j < series[i].points.size(); j++)
+        printf(", %G", series[i].points[j].y);
+      printf("]\n");
+
+      if (series[i].style == BAR_GRAPH) {
+        // There is a plt.bar function that draws bar plots,
+        // but it is *way* too slow to be useful.
+        printf(
+            "plt.vlines(x%zu, map(lambda t: min(t,0), y%zu), map(lambda t: "
+            "max(t,0), y%zu), color=rgb_colors[%zu], "
+            "label=\'%s\')\n",
+            i, i, i, i, series[i].label.c_str());
+      } else if (series[i].style == LINE_GRAPH) {
+        printf("plt.plot(x%zu, y%zu, color=rgb_colors[%zu], label=\'%s\')\n", i,
+               i, i, series[i].label.c_str());
+      } else {
+        printf("raise Exception(\"Unknown graph type\")\n");
+      }
+    }
+  }
+
+  printf("plt.xlim(%f, %f)\n", xaxis_min, xaxis_max);
+  printf("plt.ylim(%f, %f)\n", yaxis_min, yaxis_max);
+  printf("plt.xlabel(\'%s\')\n", xaxis_label.c_str());
+  printf("plt.ylabel(\'%s\')\n", yaxis_label.c_str());
+  printf("plt.title(\'%s\')\n", title.c_str());
+  if (!series.empty()) {
+    printf("plt.legend(loc=\'best\', fontsize=\'small\')\n");
+  }
+}
+
+PythonPlotCollection::PythonPlotCollection() {}
+
+PythonPlotCollection::~PythonPlotCollection() {}
+
+void PythonPlotCollection::draw() {
+  printf("import matplotlib.pyplot as plt\n");
+  printf("import colorsys\n");
+  for (size_t i = 0; i < plots.size(); i++) {
+    printf("plt.figure(%zu)\n", i);
+    plots[i]->draw();
+  }
+  printf("plt.show()\n");
+}
+
+Plot* PythonPlotCollection::append_new_plot() {
+  Plot* plot = new PythonPlot();
+  plots.push_back(std::unique_ptr<Plot>(plot));
+  return plot;
+}
+
+}  // namespace plotting
+}  // namespace webrtc