IWICBitmapSource to WriteableBitmap

gistfile1.cpp

ComPtr<IWICBitmapSource> bitmapSource = ReadFile(stream);  // 読み込みは適当に

UINT width;
UINT height;
ThrowIfFailed(bitmapSource->GetSize(&width, &height));

auto bitmapBytes = ref new Array<byte>(width * height * 4); // 32bpp前提
ThrowIfFailed(
	bitmapSource->CopyPixels(nullptr, width * 4, bitmapBytes->Length, bitmapBytes->Data)
	);

auto bitmap = ref new WriteableBitmap(width, height);
ComPtr<IBufferByteAccess> bufferByteAccess;
ComPtr<IInspectable> inspectable(reinterpret_cast<IInspectable*>(bitmap->PixelBuffer));
ThrowIfFailed(inspectable.As(&bufferByteAccess));
byte* pixels;
ThrowIfFailed(bufferByteAccess->Buffer(&pixels));
for (int i = 0; i < bitmapBytes->Length; i++)
{
	pixels[i] = bitmapBytes[i];
}