Subset decoding benchmarks

It was my goal to create benchmarks that could measure all
of the use cases that we have identified.  I think single
subsets, translating, and scaling are the important ones.

It might be a good idea to discuss the document in greater
detail as well.  I just wanted to share this to aid the
discussion.
https://docs.google.com/a/google.com/document/d/1OxW96GDMAlw6dnzNXmiNX-F9oDBBlGXzSsgd0DMIkbI/edit?usp=sharing

BUG=skia:

Review URL: https://codereview.chromium.org/1160953002

1 files changed, 46 insertions, 0 deletions

diff --git a/bench/subset/SubsetSingleBench.h b/bench/subset/SubsetSingleBench.h
new file mode 100644
index 0000000000..1484a51258
--- /dev/null
+++ b/bench/subset/SubsetSingleBench.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Benchmark.h"
+#include "SkImageDecoder.h"
+#include "SkImageInfo.h"
+#include "SkStream.h"
+#include "SkString.h"
+
+/*
+ *
+ * This benchmark is designed to test the performance of subset decoding.
+ * It uses an input width, height, left, and top to decode a single subset.
+ *
+ */
+class SubsetSingleBench : public Benchmark {
+public:
+
+    SubsetSingleBench(const SkString& path,
+                      SkColorType colorType,
+                      uint32_t subsetWidth,
+                      uint32_t subsetHeight,
+                      uint32_t offsetLeft,
+                      uint32_t offsetTop,
+                      bool useCodec);
+
+protected:
+    const char* onGetName() override;
+    bool isSuitableFor(Backend backend) override;
+    void onDraw(const int n, SkCanvas* canvas) override;
+
+private:
+    SkString                      fName;
+    SkColorType                   fColorType;
+    const uint32_t                fSubsetWidth;
+    const uint32_t                fSubsetHeight;
+    const uint32_t                fOffsetLeft;
+    const uint32_t                fOffsetTop;
+    const bool                    fUseCodec;
+    SkAutoTDelete<SkMemoryStream> fStream;
+    typedef Benchmark INHERITED;
+};