Change SkDecodingImageGenerator API

tests/ImageDecodingTest.cpp

Index: tests/ImageDecodingTest.cpp
diff --git a/tests/ImageDecodingTest.cpp b/tests/ImageDecodingTest.cpp
index bbc31cc81fed21663885bccc497bee0c3534f72c..d39a51a134f413a5680012f9d4bb84b6e8dd9aad 100644
--- a/tests/ImageDecodingTest.cpp
+++ b/tests/ImageDecodingTest.cpp
@@ -13,10 +13,13 @@
 #include "SkColorPriv.h"
 #include "SkData.h"
 #include "SkDecodingImageGenerator.h"
+#include "SkDiscardableMemoryPool.h"
 #include "SkForceLinking.h"
 #include "SkGradientShader.h"
 #include "SkImageDecoder.h"
 #include "SkImageEncoder.h"
+#include "SkImageGenerator.h"
+#include "SkImagePriv.h"
 #include "SkOSFile.h"
 #include "SkPoint.h"
 #include "SkShader.h"
@@ -153,7 +156,7 @@ static void test_unpremul(skiatest::Reporter* reporter) {
     if (iter.next(&basename)) {
         do {
             SkString filename = SkOSPath::SkPathJoin(resourcePath.c_str(), basename.c_str());
-            //SkDebugf("about to decode \"%s\"\n", filename.c_str());
+            // SkDebugf("about to decode \"%s\"\n", filename.c_str());
             compare_unpremul(reporter, filename);
         } while (iter.next(&basename));
     } else {
@@ -201,7 +204,7 @@ static void test_stream_life() {
         SkImageEncoder::kWEBP_Type,
     };
     for (size_t i = 0; i < SK_ARRAY_COUNT(gTypes); ++i) {
-        //SkDebugf("encoding to %i\n", i);
+        // SkDebugf("encoding to %i\n", i);
         SkAutoTUnref<SkMemoryStream> stream(create_image_stream(gTypes[i]));
         if (NULL == stream.get()) {
             SkDebugf("no stream\n");
@@ -228,7 +231,7 @@ static void test_stream_life() {
 // Test inside SkScaledBitmapSampler.cpp
 extern void test_row_proc_choice();
 
-#endif // SK_DEBUG
+#endif  // SK_DEBUG
 
 DEF_TEST(ImageDecoding, reporter) {
     test_unpremul(reporter);
@@ -239,6 +242,31 @@ DEF_TEST(ImageDecoding, reporter) {
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+namespace {
+// expected output for 8x8 bitmap
+const int kExpectedWidth = 8;
+const int kExpectedHeight = 8;
+const SkColor kExpectedPixels[] = {
+    0xffbba570, 0xff395f5d, 0xffe25c39, 0xff197666,
+    0xff3cba27, 0xffdefcb0, 0xffc13874, 0xfffa0093,
+    0xffbda60e, 0xffc01db6, 0xff2bd688, 0xff9362d4,
+    0xffc641b2, 0xffa5cede, 0xff606eba, 0xff8f4bf3,
+    0xff3bf742, 0xff8f02a8, 0xff5509df, 0xffc7027e,
+    0xff24aa8a, 0xff886c96, 0xff625481, 0xff403689,
+    0xffc52152, 0xff78ccd6, 0xffdcb4ab, 0xff09d27d,
+    0xffca00f3, 0xff605d47, 0xff446fb2, 0xff576e46,
+    0xff273df9, 0xffb41a83, 0xfff812c3, 0xffccab67,
+    0xff034218, 0xff7db9a7, 0xff821048, 0xfffe4ab4,
+    0xff6fac98, 0xff941d27, 0xff5fe411, 0xfffbb283,
+    0xffd86e99, 0xff169162, 0xff71128c, 0xff39cab4,
+    0xffa7fe63, 0xff4c956b, 0xffbc22e0, 0xffb272e4,
+    0xff129f4a, 0xffe34513, 0xff3d3742, 0xffbd190a,
+    0xffb07222, 0xff2e23f8, 0xfff089d9, 0xffb35738,
+    0xffa86022, 0xff3340fe, 0xff95fe71, 0xff6a71df
+};
+SK_COMPILE_ASSERT((kExpectedWidth * kExpectedHeight)
+                  == SK_ARRAY_COUNT(kExpectedPixels), array_size_mismatch);
+}  // namespace
 
 DEF_TEST(WebP, reporter) {
     const unsigned char encodedWebP[] = {
@@ -269,38 +297,26 @@ DEF_TEST(WebP, reporter) {
         0xe3, 0xfe, 0x66, 0xa4, 0x7c, 0x1b, 0x6c, 0xd1, 0xa9, 0xd8, 0x14, 0xd0,
         0xc5, 0xb5, 0x39, 0x71, 0x97, 0x19, 0x19, 0x1b
     };
-    const SkColor thePixels[]  = {
-        0xffbba570, 0xff395f5d, 0xffe25c39, 0xff197666,
-        0xff3cba27, 0xffdefcb0, 0xffc13874, 0xfffa0093,
-        0xffbda60e, 0xffc01db6, 0xff2bd688, 0xff9362d4,
-        0xffc641b2, 0xffa5cede, 0xff606eba, 0xff8f4bf3,
-        0xff3bf742, 0xff8f02a8, 0xff5509df, 0xffc7027e,
-        0xff24aa8a, 0xff886c96, 0xff625481, 0xff403689,
-        0xffc52152, 0xff78ccd6, 0xffdcb4ab, 0xff09d27d,
-        0xffca00f3, 0xff605d47, 0xff446fb2, 0xff576e46,
-        0xff273df9, 0xffb41a83, 0xfff812c3, 0xffccab67,
-        0xff034218, 0xff7db9a7, 0xff821048, 0xfffe4ab4,
-        0xff6fac98, 0xff941d27, 0xff5fe411, 0xfffbb283,
-        0xffd86e99, 0xff169162, 0xff71128c, 0xff39cab4,
-        0xffa7fe63, 0xff4c956b, 0xffbc22e0, 0xffb272e4,
-        0xff129f4a, 0xffe34513, 0xff3d3742, 0xffbd190a,
-        0xffb07222, 0xff2e23f8, 0xfff089d9, 0xffb35738,
-        0xffa86022, 0xff3340fe, 0xff95fe71, 0xff6a71df
-    };
     SkAutoDataUnref encoded(SkData::NewWithCopy(encodedWebP,
                                                 sizeof(encodedWebP)));
     SkBitmap bm;
-    bool success = SkDecodingImageGenerator::Install(encoded, &bm, NULL);
+
+    bool success = SkInstallDiscardablePixelRef(
+        SkDecodingImageGenerator::Create(encoded,
+            SkDecodingImageGenerator::Options()), &bm, NULL);
+
     REPORTER_ASSERT(reporter, success);
     if (!success) {
         return;
     }
     SkAutoLockPixels alp(bm);
-    bool rightSize = SK_ARRAY_COUNT(thePixels) == bm.width() * bm.height();
+
+    bool rightSize = ((kExpectedWidth == bm.width()) 
+                      && (kExpectedHeight == bm.height()));
     REPORTER_ASSERT(reporter, rightSize);
     if (rightSize) {
         bool error = false;
-        const SkColor* correctPixel = thePixels;
+        const SkColor* correctPixel = kExpectedPixels;
         for (int y = 0; y < bm.height(); ++y) {
             for (int x = 0; x < bm.width(); ++x) {
                 error |= (*correctPixel != bm.getColor(x, y));
@@ -310,3 +326,256 @@ DEF_TEST(WebP, reporter) {
         REPORTER_ASSERT(reporter, !error);
     }
 }
+
+////////////////////////////////////////////////////////////////////////////////
+
+// example of how Android will do this inside their BitmapFactory
+static SkPixelRef* install_pixel_ref(SkBitmap* bitmap,
+                                     SkStreamRewindable* stream,
+                                     int sampleSize, bool ditherImage) {
+    SkASSERT(bitmap != NULL);
+    SkASSERT(stream != NULL);
+    SkASSERT(stream->rewind());
+    SkASSERT(stream->unique());
+    SkColorType colorType;
+    if (!SkBitmapConfigToColorType(bitmap->config(), &colorType)) {
+        return NULL;
+    }
+    SkDecodingImageGenerator::Options opts(sampleSize, ditherImage, colorType);
+    SkAutoTDelete<SkImageGenerator> gen(
+        SkDecodingImageGenerator::Create(stream, opts));
+    SkImageInfo info;
+    if ((NULL == gen.get()) || !gen->getInfo(&info)) {
+        return NULL;
+    }
+    SkDiscardableMemory::Factory* factory = NULL;
+    if (info.getSafeSize(info.minRowBytes()) < (32 * 1024)) {
+        // only use ashmem for large images, since mmaps come at a price
+        factory = SkGetGlobalDiscardableMemoryPool();
+    }
+    if (SkInstallDiscardablePixelRef(gen.detach(), bitmap, factory)) {
+        return bitmap->pixelRef();
+    }
+    return NULL;
+}
+/**
+ *  A test for the SkDecodingImageGenerator::Create and
+ *  SkInstallDiscardablePixelRef functions.
+ */
+DEF_TEST(ImprovedBitmapFactory, reporter) {
+    SkString resourcePath = skiatest::Test::GetResourcePath();
+    SkString directory = SkOSPath::SkPathJoin(resourcePath.c_str(), "encoding");
+    SkString path = SkOSPath::SkPathJoin(directory.c_str(), "randPixels.png");
+    SkAutoTUnref<SkStreamRewindable> stream(
+        SkStream::NewFromFile(path.c_str()));
+    if (sk_exists(path.c_str())) {
+        SkBitmap bm;
+        SkAssertResult(bm.setConfig(SkBitmap::kARGB_8888_Config, 1, 1));
+        REPORTER_ASSERT(reporter,
+            NULL != install_pixel_ref(&bm, stream.detach(), 1, true));
+        SkAutoLockPixels alp(bm);
+        REPORTER_ASSERT(reporter, NULL != bm.getPixels());
+    }
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+
+#if defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_UNIX)
+static inline bool check_rounding(int value, int dividend, int divisor) {
+    // returns true if (dividend/divisor) rounds up OR down to value
+    return (((divisor * value) > (dividend - divisor))
+            && ((divisor * value) < (dividend + divisor)));
+}
+#endif  // SK_BUILD_FOR_ANDROID || SK_BUILD_FOR_UNIX
+
+
+#if SK_PMCOLOR_BYTE_ORDER(B,G,R,A)
+    #define kBackwards_SkColorType kRGBA_8888_SkColorType
+#elif SK_PMCOLOR_BYTE_ORDER(R,G,B,A)
+    #define kBackwards_SkColorType kBGRA_8888_SkColorType
+#else
+    #error "SK_*32_SHFIT values must correspond to BGRA or RGBA byte order"
+#endif
+
+static inline const char* SkColorType_to_string(SkColorType colorType) {
+    switch(colorType) {
+        case kAlpha_8_SkColorType:   return "Alpha_8";
+        case kRGB_565_SkColorType:   return "RGB_565";
+        case kARGB_4444_SkColorType: return "ARGB_4444";
+        case kPMColor_SkColorType:   return "PMColor";
+        case kBackwards_SkColorType: return "Backwards";
+        case kIndex_8_SkColorType:   return "Index_8";
+        default:                     return "ERROR";
+    }
+}
+
+/**
+ * Given either a SkStream or a SkData, try to decode the encoded
+ * image using the specified options and report errors.
+ */
+static void test_options(skiatest::Reporter* reporter,
+                         const SkDecodingImageGenerator::Options& opts,
+                         SkStreamRewindable* encodedStream,
+                         SkData* encodedData,
+                         bool useData,
+                         const SkString& path) {
+    SkBitmap bm;
+    bool success = false;
+    if (useData) {
+        if (NULL == encodedData) {
+            return;
+        }
+        success = SkInstallDiscardablePixelRef(
+            SkDecodingImageGenerator::Create(encodedData, opts), &bm, NULL);
+    } else {
+        if (NULL == encodedStream) {
+            return;
+        }
+        success = SkInstallDiscardablePixelRef(
+            SkDecodingImageGenerator::Create(encodedStream->duplicate(), opts),
+            &bm, NULL);
+    }
+    if (!success) {
+        if (opts.fUseRequestedColorType
+            && (kARGB_4444_SkColorType == opts.fRequestedColorType)) {
+            return;  // Ignore known conversion inabilities.
+        }
+        // If we get here, it's a failure and we will need more
+        // information about why it failed.
+        reporter->reportFailed(SkStringPrintf(
+            "Bounds decode failed "
+            "[sampleSize=%d dither=%s colorType=%s %s] %s:%d",
+            opts.fSampleSize, (opts.fDitherImage ? "yes" : "no"),
+            (opts.fUseRequestedColorType
+             ? SkColorType_to_string(opts.fRequestedColorType) : "(none)"),
+            path.c_str(), __FILE__, __LINE__));
+        return;
+    }
+    #if defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_UNIX)
+    // Android is the only system that use Skia's image decoders in
+    // production.  For now, we'll only verify that samplesize works
+    // on systems where it already is known to work.
+    REPORTER_ASSERT(reporter, check_rounding(bm.height(), kExpectedHeight,
+                                             opts.fSampleSize));
+    REPORTER_ASSERT(reporter, check_rounding(bm.width(), kExpectedWidth,
+                                             opts.fSampleSize));
+    #endif  // SK_BUILD_FOR_ANDROID || SK_BUILD_FOR_UNIX
+    SkAutoLockPixels alp(bm);
+    if (bm.getPixels() == NULL) {
+        reporter->reportFailed(SkStringPrintf(
+            "Pixel decode failed "
+            "[sampleSize=%d dither=%s colorType=%s %s] %s:%d",
+            opts.fSampleSize, (opts.fDitherImage ? "yes" : "no"),
+            (opts.fUseRequestedColorType
+             ? SkColorType_to_string(opts.fRequestedColorType) : "(none)"),
+            path.c_str(), __FILE__, __LINE__));
+        return;
+    }
+
+    SkBitmap::Config requestedConfig
+        = SkColorTypeToBitmapConfig(opts.fRequestedColorType);
+    REPORTER_ASSERT(reporter,
+                    (!opts.fUseRequestedColorType)
+                    || (bm.config() == requestedConfig));
+
+    // Condition under which we should check the decoding results:
+    if ((SkBitmap::kARGB_8888_Config == bm.config())
+        && (!path.endsWith(".jpg"))  // lossy
+        && (opts.fSampleSize == 1)) {  // scaled
+        const SkColor* correctPixels = kExpectedPixels;
+        SkASSERT(bm.height() == kExpectedHeight);
+        SkASSERT(bm.width() == kExpectedWidth);
+        int pixelErrors = 0;
+        for (int y = 0; y < bm.height(); ++y) {
+            for (int x = 0; x < bm.width(); ++x) {
+                if (*correctPixels != bm.getColor(x, y)) {
+                    ++pixelErrors;
+                }
+                ++correctPixels;
+            }
+        }
+        if (pixelErrors != 0) {
+            reporter->reportFailed(SkStringPrintf(
+                "Pixel-level mismatch (%d of %d) [sampleSize=%d "
+                "dither=%s colorType=%s %s] %s:%d",
+                pixelErrors, kExpectedHeight * kExpectedWidth,
+                opts.fSampleSize, (opts.fDitherImage ? "yes" : "no"),
+                (opts.fUseRequestedColorType
+                 ? SkColorType_to_string(opts.fRequestedColorType)
+                 : "(none)"), path.c_str(), __FILE__, __LINE__));
+        }
+    }
+}
+
+/**
+ *  SkDecodingImageGenerator has an Options struct which lets the
+ *  client of the generator set sample size, dithering, and bitmap
+ *  config.  This test loops through many possible options and tries
+ *  them on a set of 5 small encoded images (each in a different
+ *  format).  We test both SkData and SkStreamRewindable decoding.
+ */
+DEF_TEST(ImageDecoderOptions, reporter) {
+    const char* files[]  = {
+        "randPixels.bmp",
+        "randPixels.jpg",
+        "randPixels.png",
+        "randPixels.webp",
+        #if !defined(SK_BUILD_FOR_WIN)
+        // TODO(halcanary): Find out why this fails sometimes.
+        "randPixels.gif",
+        #endif
+    };
+
+    SkString resourceDir = skiatest::Test::GetResourcePath();
+    SkString directory = SkOSPath::SkPathJoin(resourceDir.c_str(), "encoding");
+    if (!sk_exists(directory.c_str())) {
+        return;
+    }
+
+    int scaleList[] = {1, 2, 3, 4};
+    bool ditherList[] = {true, false};
+    SkColorType colorList[] = {
+        kAlpha_8_SkColorType,
+        kRGB_565_SkColorType,
+        kARGB_4444_SkColorType,  // Most decoders will fail on 4444.
+        kPMColor_SkColorType
+        // Note that indexed color is left out of the list.  Lazy
+        // decoding doesn't do indexed color.
+    };
+    const bool useDataList[] = {true, false};
+
+    for (size_t fidx = 0; fidx < SK_ARRAY_COUNT(files); ++fidx) {
+        SkString path = SkOSPath::SkPathJoin(directory.c_str(), files[fidx]);
+        if (!sk_exists(path.c_str())) {
+            continue;
+        }
+
+        SkAutoDataUnref encodedData(SkData::NewFromFileName(path.c_str()));
+        REPORTER_ASSERT(reporter, encodedData.get() != NULL);
+        SkAutoTUnref<SkStreamRewindable> encodedStream(
+            SkStream::NewFromFile(path.c_str()));
+        REPORTER_ASSERT(reporter, encodedStream.get() != NULL);
+
+        for (size_t i = 0; i < SK_ARRAY_COUNT(scaleList); ++i) {
+            for (size_t j = 0; j < SK_ARRAY_COUNT(ditherList); ++j) {
+                for (size_t m = 0; m < SK_ARRAY_COUNT(useDataList); ++m) {
+                    for (size_t k = 0; k < SK_ARRAY_COUNT(colorList); ++k) {
+                        SkDecodingImageGenerator::Options opts(scaleList[i],
+                                                               ditherList[j],
+                                                               colorList[k]);
+                        test_options(reporter, opts, encodedStream, encodedData,
+                                     useDataList[m], path);
+
+                    }
+                    SkDecodingImageGenerator::Options options(scaleList[i],
+                                                              ditherList[j]);
+                    test_options(reporter, options, encodedStream, encodedData,
+                                 useDataList[m], path);
+                }
+            }
+        }
+    }
+}
+////////////////////////////////////////////////////////////////////////////////
+