force opaque if kCGImageAlpha returns None
BUG=skia:2424
R=caryclark@google.com
Author: reed@google.com
Review URL: https://codereview.chromium.org/355403003
diff --git a/src/ports/SkImageDecoder_CG.cpp b/src/ports/SkImageDecoder_CG.cpp
index 8bf30d2..7bebf39 100644
--- a/src/ports/SkImageDecoder_CG.cpp
+++ b/src/ports/SkImageDecoder_CG.cpp
@@ -50,6 +50,56 @@
virtual bool onDecode(SkStream* stream, SkBitmap* bm, Mode);
};
+static void argb_4444_force_opaque(void* row, int count) {
+ uint16_t* row16 = (uint16_t*)row;
+ for (int i = 0; i < count; ++i) {
+ row16[i] |= 0xF000;
+ }
+}
+
+static void argb_8888_force_opaque(void* row, int count) {
+ // can use RGBA or BGRA, they have the same shift for alpha
+ const uint32_t alphaMask = 0xFF << SK_RGBA_A32_SHIFT;
+ uint32_t* row32 = (uint32_t*)row;
+ for (int i = 0; i < count; ++i) {
+ row32[i] |= alphaMask;
+ }
+}
+
+static void alpha_8_force_opaque(void* row, int count) {
+ memset(row, 0xFF, count);
+}
+
+static void force_opaque(SkBitmap* bm) {
+ SkAutoLockPixels alp(*bm);
+ if (!bm->getPixels()) {
+ return;
+ }
+
+ void (*proc)(void*, int);
+ switch (bm->colorType()) {
+ case kARGB_4444_SkColorType:
+ proc = argb_4444_force_opaque;
+ break;
+ case kRGBA_8888_SkColorType:
+ case kBGRA_8888_SkColorType:
+ proc = argb_8888_force_opaque;
+ break;
+ case kAlpha_8_SkColorType:
+ proc = alpha_8_force_opaque;
+ break;
+ default:
+ return;
+ }
+
+ char* row = (char*)bm->getPixels();
+ for (int y = 0; y < bm->height(); ++y) {
+ proc(row, bm->width());
+ row += bm->rowBytes();
+ }
+ bm->setAlphaType(kOpaque_SkAlphaType);
+}
+
#define BITMAP_INFO (kCGBitmapByteOrder32Big | kCGImageAlphaPremultipliedLast)
bool SkImageDecoder_CG::onDecode(SkStream* stream, SkBitmap* bm, Mode mode) {
@@ -89,8 +139,10 @@
case kCGImageAlphaNone:
case kCGImageAlphaNoneSkipLast:
case kCGImageAlphaNoneSkipFirst:
- SkASSERT(SkBitmap::ComputeIsOpaque(*bm));
- bm->setAlphaType(kOpaque_SkAlphaType);
+ // We're opaque, but we can't rely on the data always having 0xFF
+ // in the alpha slot (which Skia wants), so we have to ram it in
+ // ourselves.
+ force_opaque(bm);
break;
default:
// we don't know if we're opaque or not, so compute it.