SkCodec: add wbmp class

tests/CodexTest.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 "Resources.h"
+#include "SkBitmap.h"
+#include "SkCodec.h"
+#include "SkMD5.h"
+#include "Test.h"
+
+static SkStreamAsset* resource(const char path[]) {
+    SkString fullPath = GetResourcePath(path);
+    return SkStream::NewFromFile(fullPath.c_str());
+}
+
+static void md5(const SkBitmap& bm, SkMD5::Digest* digest) {
+    SkAutoLockPixels autoLockPixels(bm);
+    SkASSERT(bm.getPixels());
+    SkMD5 md5;
+    size_t rowLen = bm.info().bytesPerPixel() * bm.width();
+    for (int y = 0; y < bm.height(); ++y) {
+        md5.update(static_cast<uint8_t*>(bm.getAddr(0, y)), rowLen);
+    }
+    md5.finish(*digest);
+}
+
+static void check(skiatest::Reporter* r,
+                  const char path[],
+                  SkISize size,
+                  bool canRewind) {
+    SkAutoTDelete<SkStream> stream(resource(path));
+    if (!stream) {
+        SkDebugf("Missing resource '%s'\n", path);
+        return;
+    }
+    SkAutoTDelete<SkImageGenerator> gen(
+            SkCodec::NewFromStream(stream.detach()));
+    if (!gen) {
+        ERRORF(r, "Unable to decode '%s'", path);
+        return;
+    }
+    SkImageInfo info = gen->getInfo();
+    REPORTER_ASSERT(r, info.dimensions() == size);
+    SkBitmap bm;
+    bm.allocPixels(info);
+    SkAutoLockPixels autoLockPixels(bm);
+    SkImageGenerator::Result result =
+        gen->getPixels(info, bm.getPixels(), bm.rowBytes(), NULL, NULL, NULL);
+    REPORTER_ASSERT(r, result == SkImageGenerator::kSuccess);
+
+    SkMD5::Digest digest1, digest2;
+    md5(bm, &digest1);
+
+    bm.eraseColor(SK_ColorYELLOW);
+
+    result =
+        gen->getPixels(info, bm.getPixels(), bm.rowBytes(), NULL, NULL, NULL);
+
+    // All ImageGenerators should support re-decoding the pixels.
+    // It is a known bug that some can not.
+    if (canRewind) {
+        REPORTER_ASSERT(r, result == SkImageGenerator::kSuccess);
+        // verify that re-decoding gives the same result.
+        md5(bm, &digest2);
+        REPORTER_ASSERT(r, digest1 == digest2);
+    }
+}
+
+DEF_TEST(Codec, r) {
+    // WBMP
+    check(r, "mandrill.wbmp", SkISize::Make(512, 512), true);
+
+    // BMP
+    // TODO (msarett): SkBmpCodec should be able to rewind.
+    check(r, "randPixels.bmp", SkISize::Make(8, 8), false);
+
+    // ICO
+    // TODO (msarett): SkIcoCodec should be able to rewind.
+    check(r, "color_wheel.ico", SkISize::Make(128, 128), false);
+
+    // PNG
+    // TODO (scroggo): SkPngCodec should be able to rewind.
+    check(r, "arrow.png", SkISize::Make(187, 312), false);
+    check(r, "baby_tux.png", SkISize::Make(240, 246), false);
+    check(r, "color_wheel.png", SkISize::Make(128, 128), false);
+    check(r, "half-transparent-white-pixel.png", SkISize::Make(1, 1), false);
+    check(r, "mandrill_128.png", SkISize::Make(128, 128), false);
+    check(r, "mandrill_16.png", SkISize::Make(16, 16), false);
+    check(r, "mandrill_256.png", SkISize::Make(256, 256), false);
+    check(r, "mandrill_32.png", SkISize::Make(32, 32), false);
+    check(r, "mandrill_512.png", SkISize::Make(512, 512), false);
+    check(r, "mandrill_64.png", SkISize::Make(64, 64), false);
+    check(r, "plane.png", SkISize::Make(250, 126), false);
+    check(r, "randPixels.png", SkISize::Make(8, 8), false);
+    check(r, "yellow_rose.png", SkISize::Make(400, 301), false);
+}