Fine scale the decoded result to match the desired sampleSize.
Bug: 27097032
Change-Id: Ie15a3116cdd6988524977e5390f6edbac224e502
diff --git a/core/jni/android/graphics/BitmapFactory.cpp b/core/jni/android/graphics/BitmapFactory.cpp
index 29c1075..fb9b1e5 100644
--- a/core/jni/android/graphics/BitmapFactory.cpp
+++ b/core/jni/android/graphics/BitmapFactory.cpp
@@ -201,6 +201,26 @@
const unsigned int mSize;
};
+// Necessary for decodes when the native decoder cannot scale to appropriately match the sampleSize
+// (for example, RAW). If the sampleSize divides evenly into the dimension, we require that the
+// scale matches exactly. If sampleSize does not divide evenly, we allow the decoder to choose how
+// best to round.
+static bool needsFineScale(const int fullSize, const int decodedSize, const int sampleSize) {
+ if (fullSize % sampleSize == 0 && fullSize / sampleSize != decodedSize) {
+ return true;
+ } else if ((fullSize / sampleSize + 1) != decodedSize &&
+ (fullSize / sampleSize) != decodedSize) {
+ return true;
+ }
+ return false;
+}
+
+static bool needsFineScale(const SkISize fullSize, const SkISize decodedSize,
+ const int sampleSize) {
+ return needsFineScale(fullSize.width(), decodedSize.width(), sampleSize) ||
+ needsFineScale(fullSize.height(), decodedSize.height(), sampleSize);
+}
+
static jobject doDecode(JNIEnv* env, SkStreamRewindable* stream, jobject padding, jobject options) {
// This function takes ownership of the input stream. Since the SkAndroidCodec
// will take ownership of the stream, we don't necessarily need to take ownership
@@ -250,7 +270,6 @@
}
}
}
- const bool willScale = scale != 1.0f;
// Create the codec.
NinePatchPeeker peeker;
@@ -269,15 +288,28 @@
prefColorType = kN32_SkColorType;
}
- // Determine the output size and return if the client only wants the size.
+ // Determine the output size.
SkISize size = codec->getSampledDimensions(sampleSize);
+
+ int scaledWidth = size.width();
+ int scaledHeight = size.height();
+ bool willScale = false;
+
+ // Apply a fine scaling step if necessary.
+ if (needsFineScale(codec->getInfo().dimensions(), size, sampleSize)) {
+ willScale = true;
+ scaledWidth = codec->getInfo().width() / sampleSize;
+ scaledHeight = codec->getInfo().height() / sampleSize;
+ }
+
+ // Set the options and return if the client only wants the size.
if (options != NULL) {
jstring mimeType = encodedFormatToString(env, codec->getEncodedFormat());
if (env->ExceptionCheck()) {
return nullObjectReturn("OOM in encodedFormatToString()");
}
- env->SetIntField(options, gOptions_widthFieldID, size.width());
- env->SetIntField(options, gOptions_heightFieldID, size.height());
+ env->SetIntField(options, gOptions_widthFieldID, scaledWidth);
+ env->SetIntField(options, gOptions_heightFieldID, scaledHeight);
env->SetObjectField(options, gOptions_mimeFieldID, mimeType);
if (onlyDecodeSize) {
@@ -285,6 +317,13 @@
}
}
+ // Scale is necessary due to density differences.
+ if (scale != 1.0f) {
+ willScale = true;
+ scaledWidth = static_cast<int>(scaledWidth * scale + 0.5f);
+ scaledHeight = static_cast<int>(scaledHeight * scale + 0.5f);
+ }
+
android::Bitmap* reuseBitmap = nullptr;
unsigned int existingBufferSize = 0;
if (javaBitmap != NULL) {
@@ -381,13 +420,6 @@
return nullObjectReturn("codec->getAndroidPixels() failed.");
}
- int scaledWidth = size.width();
- int scaledHeight = size.height();
- if (willScale) {
- scaledWidth = int(scaledWidth * scale + 0.5f);
- scaledHeight = int(scaledHeight * scale + 0.5f);
- }
-
jbyteArray ninePatchChunk = NULL;
if (peeker.mPatch != NULL) {
if (willScale) {