add decode bench
add dictionary for bench tools to see optional cmdline args



git-svn-id: http://skia.googlecode.com/svn/trunk@351 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/bench/DecodeBench.cpp b/bench/DecodeBench.cpp
new file mode 100644
index 0000000..6abd054
--- /dev/null
+++ b/bench/DecodeBench.cpp
@@ -0,0 +1,53 @@
+#include "SkBenchmark.h"
+#include "SkBitmap.h"
+#include "SkImageDecoder.h"
+#include "SkString.h"
+
+static const char* gConfigName[] = {
+    "ERROR", "a1", "a8", "index8", "565", "4444", "8888"
+};
+
+class DecodeBench : public SkBenchmark {
+    const char* fFilename;
+    SkBitmap::Config fPrefConfig;
+    SkString fName;
+    enum { N = 10 };
+public:
+    DecodeBench(void* param, SkBitmap::Config c) : SkBenchmark(param) {
+        fFilename = this->findDefine("decode-filename");
+        fPrefConfig = c;
+        
+        const char* fname = NULL;
+        if (fFilename) {
+            fname = strrchr(fFilename, '/');
+            if (fname) {
+                fname += 1; // skip the slash
+            }
+        }
+        fName.printf("decode_%s_%s", gConfigName[c], fname);
+    }
+
+protected:
+    virtual const char* onGetName() {
+        return fName.c_str();
+    }
+
+    virtual void onDraw(SkCanvas* canvas) {
+        for (int i = 0; i < N; i++) {
+            SkBitmap bm;
+            SkImageDecoder::DecodeFile(fFilename, &bm, fPrefConfig,
+                                       SkImageDecoder::kDecodePixels_Mode);
+        }
+    }
+
+private:
+    typedef SkBenchmark INHERITED;
+};
+
+static SkBenchmark* Fact0(void* p) { return new DecodeBench(p, SkBitmap::kARGB_8888_Config); }
+static SkBenchmark* Fact1(void* p) { return new DecodeBench(p, SkBitmap::kRGB_565_Config); }
+static SkBenchmark* Fact2(void* p) { return new DecodeBench(p, SkBitmap::kARGB_4444_Config); }
+
+static BenchRegistry gReg0(Fact0);
+static BenchRegistry gReg1(Fact1);
+static BenchRegistry gReg2(Fact2);