Bmp Image Decoding

src/codec/SkCodec_libpng.cpp

Index: src/codec/SkCodec_libpng.cpp
diff --git a/src/codec/SkCodec_libpng.cpp b/src/codec/SkCodec_libpng.cpp
index 3d8d4b5634f72f14f3e9f90d945f956064d6f483..d9e5db816d10c76f319cbd0dbb893587c0d8c3e9 100644
--- a/src/codec/SkCodec_libpng.cpp
+++ b/src/codec/SkCodec_libpng.cpp
@@ -445,10 +445,10 @@ SkCodec::Result SkPngCodec::onGetPixels(const SkImageInfo& requestedInfo, void*
     // made in the factory.
     png_read_update_info(fPng_ptr, fInfo_ptr);
 
+    const int bpp = SkSwizzler::BitsPerPixel(sc) / 8;

[scroggo, 2015/03/06 18:56:14]

This makes me nervous that we've messed up if BitsPerPixel was *not* divisible
by 8. Can we make this a helper function in SkSwizzler?:

  int BytesPerPixel(SrcConfig sc) {
    SkASSERT(SkIsAlign4(BitsPerPixel(sc)));
    return BitsPerPixel >> 3;
  }

     if (numberPasses > 1) {
         const int width = requestedInfo.width();
         const int height = requestedInfo.height();
-        const int bpp = SkSwizzler::BytesPerPixel(sc);
         const size_t rowBytes = width * bpp;
 
         storage.reset(width * height * bpp);
@@ -470,7 +470,7 @@ SkCodec::Result SkPngCodec::onGetPixels(const SkImageInfo& requestedInfo, void*
             row += rowBytes;
         }
     } else {
-        storage.reset(requestedInfo.width() * SkSwizzler::BytesPerPixel(sc));
+        storage.reset(requestedInfo.width() * bpp);
         uint8_t* srcRow = static_cast<uint8_t*>(storage.get());
         for (int y = 0; y < requestedInfo.height(); y++) {
             png_read_rows(fPng_ptr, &srcRow, png_bytepp_NULL, 1);