Add comment to media bench clarifying library initialization.

media/bench/bench.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Standalone benchmarking application based on FFmpeg.  This tool is used to
 // measure decoding performance between different FFmpeg compile and run-time
 // options.  We also use this tool to measure performance regressions when
 // testing newer builds of FFmpeg from trunk.
 
 #include <iomanip>
@@ skipping 30 matching lines @@
               << "Benchmark either the audio or video stream\n"
               << "  --video-threads=N               "
               << "Decode video using N threads\n"
               << "  --fast2                         "
               << "Enable fast2 flag\n"
               << "  --skip=[1|2|3]                  "
               << "1=loop nonref, 2=loop, 3= frame nonref" << std::endl;
     return 1;
   }
 
-  media::InitializeMediaLibrary(FilePath());
+  // Initialize our media library (try loading DLLs, etc.) before continuing.
+  // We use an empty file path as the parameter to force searching of the
+  // default locations for necessary DLLs and DSOs.
+  if (media::InitializeMediaLibrary(FilePath()) == false) {
+    std::cerr << "Unable to initialize the media library.";
+    return 1;
+  }
 
   // Retrieve command line options.
   std::string path(WideToUTF8(filenames[0]));
   CodecType target_codec = CODEC_TYPE_UNKNOWN;
   int video_threads = 0;
 
   // Determine whether to benchmark audio or video decoding.
   std::wstring stream(cmd_line->GetSwitchValue(switches::kStream));
   if (!stream.empty()) {
     if (stream.compare(L"audio") == 0) {
@@ skipping 174 matching lines @@
   std::cout << "      Total:" << std::setw(10) << total.InMillisecondsF()
             << " ms" << std::endl;
   std::cout << "  Summation:" << std::setw(10) << sum
             << " ms" << std::endl;
   std::cout << "    Average:" << std::setw(10) << average
             << " ms" << std::endl;
   std::cout << "     StdDev:" << std::setw(10) << stddev
             << " ms" << std::endl;
   return 0;
 }