Integration of most changes from the GoogleTV project around the convolver/sc...

skia/ext/image_operations_bench.cc

Index: skia/ext/image_operations_bench.cc
===================================================================
--- skia/ext/image_operations_bench.cc	(revision 0)
+++ skia/ext/image_operations_bench.cc	(revision 0)
@@ -0,0 +1,279 @@
+// Copyright (c) 2010 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.
+
+#include <stdio.h>

[brettw, 2010/12/17 20:07:55]

Can you write a comment at the top of the file giving a quick overview about
what this program does?

[evannier, 2010/12/19 00:15:03]

Done.

+
+#include "base/basictypes.h"
+#include "base/command_line.h"
+#include "base/format_macros.h"
+#include "base/string_number_conversions.h"
+#include "base/string_split.h"
+#include "base/string_util.h"
+#include "base/time.h"
+#include "base/utf_string_conversions.h"
+#include "skia/ext/image_operations.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "third_party/skia/include/core/SkRect.h"
+
+namespace {

[brettw, 2010/12/17 20:07:55]

Please put a blank line on both sides of namespace begin/end.

[evannier, 2010/12/19 00:15:03]

Done.

+struct StringMethodPair {
+  const char* name;
+  skia::ImageOperations::ResizeMethod method;
+};
+#define ADD_METHOD(x) { #x, skia::ImageOperations::RESIZE_##x }
+const StringMethodPair resize_methods[] = {
+  ADD_METHOD(GOOD),
+  ADD_METHOD(BETTER),
+  ADD_METHOD(BEST),
+  ADD_METHOD(BOX),
+  ADD_METHOD(HAMMING1),
+  ADD_METHOD(LANCZOS2),
+  ADD_METHOD(LANCZOS3),
+  ADD_METHOD(SUBPIXEL)
+};
+
+// converts a string into one of the image operation method to resize.
+// @return true on success, false otherwise.
+bool StringToMethod(const std::string& arg,
+                    skia::ImageOperations::ResizeMethod* method) {
+  for (size_t i = 0; i < arraysize(resize_methods); ++i) {
+    if (base::strcasecmp(arg.c_str(), resize_methods[i].name) == 0) {
+      *method = resize_methods[i].method;
+      return true;
+    }
+  }
+  return false;
+}
+
+const char* MethodToString(skia::ImageOperations::ResizeMethod method) {
+  for (size_t i = 0; i < arraysize(resize_methods); ++i) {
+    if (method == resize_methods[i].method) {
+      return resize_methods[i].name;
+    }
+  }
+  return "unknown";
+}
+
+// Prints all supported resize methods
+void PrintMethods() {
+  bool print_comma = false;
+  for (size_t i = 0; i < arraysize(resize_methods); ++i) {
+    if (print_comma) {
+      printf(",");
+    } else {
+      print_comma = true;
+    }
+    printf(" %s", resize_methods[i].name);
+  }
+}
+
+// @return the number of bytes that the bitmap has. This number is different

[brettw, 2010/12/17 20:07:55]

We don't use the doxygen-style comments. Can you change the @ stuff to just be
normal sentences ("Returns the number...").

[evannier, 2010/12/19 00:15:03]

Done.

+// from what SkBitmap::getSize() returns since it does not take into account
+// the stride. The difference between the stride and the width can be large
+// because of the alignment constraints on bitmaps created for SRB scaling
+// (32 pixels). Using this metric instead of the getSize seemed to be a more
+// accurate representation of the work done (even though in terms of memory
+// bandwidth that might be similar because of the cache line size).
+// @return the number of bytes of the image.
+int GetBitmapSize(const SkBitmap* bitmap) {
+  return bitmap->height() * bitmap->bytesPerPixel() * bitmap->width();
+}
+
+// Simple class to represent dimensions of a bitmap (width, height).
+class Dimensions {
+ public:
+  Dimensions() :

[brettw, 2010/12/17 20:07:55]

Style: this can all go on one line (I would probably do this method in this
case), or put the : on the next line indented 4 spaces (use this when not
everything fits on one line).

[evannier, 2010/12/19 00:15:03]

Done. i left on separate lines, but moved the ':'

+      width_(0),
+      height_(0) {}
+
+  void set(int w, int h) {
+    width_ = w;
+    height_ = h;
+  }
+
+  int width() const {
+    return width_;
+  }
+
+  int height() const {
+    return height_;
+  }
+
+  bool IsValid() const {
+    return (width_ > 0 && height_ > 0);
+  }
+
+  // On failure, will set its state in such a way that IsValid will return
+  // false.
+  void FromString(const std::string& arg) {
+    std::vector<std::string> strings;
+    base::SplitString(std::string(arg), 'x', &strings);
+    if (strings.size() != 2 ||
+        base::StringToInt(strings[0], &width_) == false ||
+        base::StringToInt(strings[1], &height_) == false) {
+      width_ = -1;  // force the dimension object to be invalid.
+    }
+  }
+ private:
+  int width_;
+  int height_;
+};
+
+// main class used for the benchmarking.
+class Benchmark {
+ public:
+  static const int kDefaultNumberIterations;
+  static const skia::ImageOperations::ResizeMethod kDefaultResizeMethod;
+
+  Benchmark() :

[brettw, 2010/12/17 20:07:55]

Ditto.

[evannier, 2010/12/19 00:15:03]

Done.

+      num_iterations_(kDefaultNumberIterations),
+      method_(kDefaultResizeMethod) {}
+
+  // @return true if command line parsing was successful, false otherwise.
+  bool ParseArgs(const CommandLine* command_line);
+
+  // @returns true if successful, false otherwise.
+  bool Run() const;
+
+  static void Usage();
+ private:
+  int num_iterations_;
+  skia::ImageOperations::ResizeMethod method_;
+  Dimensions source_;
+  Dimensions dest_;
+};
+
+// static
+const int Benchmark::kDefaultNumberIterations = 1024;
+const skia::ImageOperations::ResizeMethod Benchmark::kDefaultResizeMethod =
+      skia::ImageOperations::RESIZE_LANCZOS3;
+
+// argument management
+void Benchmark::Usage() {
+  printf("image_operations_bench -source wxh -destination wxh "
+         "[-iterations i] [-method m] [-help]\n"
+         "  -source wxh: specify source width and height\n"
+         "  -destination wxh: specify destination width and height\n"
+         "  -iter i: perform i iterations (default:%d)\n"
+         "  -method m: use method m (default:%s), which can be:",
+         Benchmark::kDefaultNumberIterations,
+         MethodToString(Benchmark::kDefaultResizeMethod));
+  PrintMethods();
+  printf("\n  -help: prints this help and exits\n");
+}
+
+bool Benchmark::ParseArgs(const CommandLine* command_line) {
+  const CommandLine::SwitchMap& switches = command_line->GetSwitches();
+  bool fNeedHelp = false;
+
+  for (CommandLine::SwitchMap::const_iterator iter = switches.begin();
+       iter != switches.end();
+       ++iter) {
+    const std::string& s = iter->first;
+    std::string value;
+#if defined(OS_WIN)
+    value = WideToUTF8(iter->second);
+#else
+    value = iter->second;
+#endif
+    if (s == "source") {
+      source_.FromString(value);
+    } else if (s == "destination") {
+      dest_.FromString(value);
+    } else if (s == "iterations") {
+      if (base::StringToInt(value, &num_iterations_) == false) {
+        fNeedHelp = true;
+      }
+    } else if (s == "method") {
+      if (!StringToMethod(value, &method_)) {
+        printf("Invalid method '%s' specified\n", value.c_str());
+        fNeedHelp = true;
+      }
+    } else {
+      fNeedHelp = true;
+    }
+  }
+
+  if (num_iterations_ <= 0) {
+    printf("Invalid number of iterations: %d\n", num_iterations_);
+    fNeedHelp = true;
+  }
+  if (!source_.IsValid()) {
+    printf("Invalid source dimensions specified\n");
+    fNeedHelp = true;
+  }
+  if (!dest_.IsValid()) {
+    printf("Invalid dest dimensions specified\n");
+    fNeedHelp = true;
+  }
+  if (fNeedHelp == true) {
+    return false;
+  }
+  return true;
+}
+
+// actual benchmark.
+bool Benchmark::Run() const {
+  SkBitmap source;
+  source.setConfig(SkBitmap::kARGB_8888_Config,
+                   source_.width(), source_.height());
+  source.allocPixels();
+  source.eraseARGB(0, 0, 0, 0);
+
+  SkBitmap dest;
+
+  const base::TimeTicks start = base::TimeTicks::Now();
+
+  for (int i = 0; i < num_iterations_; ++i) {
+    dest = skia::ImageOperations::Resize(source,
+                                         method_,
+                                         dest_.width(), dest_.height());
+  }
+
+  const int64 elapsed_us = (base::TimeTicks::Now() - start).InMicroseconds();
+
+  const uint64 num_bytes = static_cast<uint64>(num_iterations_) *
+      (GetBitmapSize(&source) + GetBitmapSize(&dest));
+
+  printf("%"PRIu64" MB/s,\telapsed = %"PRIu64" source=%d dest=%d\n",
+         static_cast<uint64>(elapsed_us == 0 ? 0 : num_bytes / elapsed_us),
+         static_cast<uint64>(elapsed_us),
+         GetBitmapSize(&source), GetBitmapSize(&dest));
+
+  return true;
+}
+
+// A small class to automatically call Reset on the global command line to
+// avoid nasty valgrind complaints for the leak of the global command line.
+class CommandLineAutoReset {
+ public:
+  CommandLineAutoReset(int argc, char** argv) {
+    CommandLine::Init(argc, argv);
+  }
+  ~CommandLineAutoReset() {
+    CommandLine::Reset();
+  }
+
+  const CommandLine* Get() const {
+    return CommandLine::ForCurrentProcess();
+  }
+};
+}  // anonymous namespace

[brettw, 2010/12/17 20:07:55]

Just "//  namespace" is sufficient. Also, be sure there's a blank line on each
side of it.

[evannier, 2010/12/19 00:15:03]

Done.

+
+int main(int argc, char** argv) {
+  Benchmark bench;
+  CommandLineAutoReset command_line(argc, argv);
+
+  if (!bench.ParseArgs(command_line.Get())) {
+    Benchmark::Usage();
+    return 1;
+  }
+
+  if (!bench.Run()) {
+    printf("Failed to run benchmark\n");
+    return 1;
+  }
+
+  return 0;
+}