Add timing SkCodec to nanobench.

bench/CodecBench.cpp

+/*
+ * 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 "CodecBench.h"
+#include "SkBitmap.h"
+#include "SkCodec.h"
+#include "SkImageGenerator.h"
+#include "SkOSFile.h"
+
+CodecBench::CodecBench(SkString baseName, SkData* encoded, SkColorType colorType)
+    : fColorType(colorType)
+    , fData(SkRef(encoded))
+{
+    // Parse filename and the color type to give the benchmark a useful name
+    const char* colorName;
+    switch(colorType) {
+        case kN32_SkColorType:
+            colorName = "N32";
+            break;
+        case kRGB_565_SkColorType:
+            colorName = "565";
+            break;
+        case kAlpha_8_SkColorType:
+            colorName = "Alpha8";
+            break;
+        default:
+            colorName = "Unknown";
+    }
+    fName.printf("Codec_%s_%s", baseName.c_str(), colorName);
+#ifdef SK_DEBUG
+    // Ensure that we can create an SkCodec from this data.
+    SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(fData));
+    SkASSERT(codec);
+#endif
+}
+
+const char* CodecBench::onGetName() {
+    return fName.c_str();
+}
+
+bool CodecBench::isSuitableFor(Backend backend) {
+    return kNonRendering_Backend == backend;
+}
+
+void CodecBench::onPreDraw() {
+    SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(fData));
+    fBitmap.allocPixels(codec->getInfo().makeColorType(fColorType));
+}
+
+void CodecBench::onDraw(const int n, SkCanvas* canvas) {
+    SkAutoTDelete<SkCodec> codec;
+    for (int i = 0; i < n; i++) {
+        codec.reset(SkCodec::NewFromData(fData));
+#ifdef SK_DEBUG
+        const SkImageGenerator::Result result =
+#endif
+        // fBitmap.info() was set to use fColorType in onPreDraw.
+        codec->getPixels(fBitmap.info(), fBitmap.getPixels(), fBitmap.rowBytes());
+        SkASSERT(result == SkImageGenerator::kSuccess
+                 || result == SkImageGenerator::kIncompleteInput);
+    }
+}