private void FromStream(Stream stm, string filename)
{
Debug.Assert(stm != null);
int bufferSize = _bufferSizeIncrement;
if (stm.CanSeek)
{
bufferSize = (int)stm.Length + 1; // If this stream is seekable (most cases), we will only have one buffer alloc and read below
// otherwise, we will incrementally grow the buffer and read until end of profile.
// profiles are typcially small, so usually one allocation will suffice
}
byte[] rawBytes = new byte[bufferSize];
int numBytesRead = 0;
while (bufferSize < _maximumColorContextLength)
{
numBytesRead += stm.Read(rawBytes, numBytesRead, bufferSize - numBytesRead);
if (numBytesRead < bufferSize)
{
FromRawBytes(rawBytes, numBytesRead, /* dontThrowException = */ false);
using (FactoryMaker factoryMaker = new FactoryMaker())
{
HRESULT.Check(UnsafeNativeMethodsMilCoreApi.WICCodec.CreateColorContext(factoryMaker.ImagingFactoryPtr, out _colorContextHandle));
HRESULT.Check(IWICCC.InitializeFromMemory(_colorContextHandle, rawBytes, (uint)numBytesRead));
}
return;
}
else
{
bufferSize += _bufferSizeIncrement;
byte[] newRawBytes = new byte[bufferSize];
rawBytes.CopyTo(newRawBytes, 0);
rawBytes = newRawBytes;
}
}
throw new ArgumentException(SR.Get(SRID.ColorContext_FileTooLarge), filename);
}
/// <summary>
/// Create a ColorContext from an unmanaged color context
/// </summary>
private ColorContext(SafeMILHandle colorContextHandle)
{
_colorContextHandle = colorContextHandle;
//
// For 3.* backwards compat, we aren't going to HRESULT.Check() anywhere because
// that could introduce new exceptions. If anything fails, _colorContextHelper
// will be invalid and we'll emulate the old failure behavior later in
// OpenProfileStream()
//
IWICCC.WICColorContextType type;
if (HRESULT.Failed(IWICCC.GetType(_colorContextHandle, out type)))
{
return;
}
switch (type)
{
case IWICCC.WICColorContextType.WICColorContextProfile:
uint cbProfileActual;
int hr = IWICCC.GetProfileBytes(_colorContextHandle, 0, null, out cbProfileActual);
if (HRESULT.Succeeded(hr) && cbProfileActual != 0)
{
byte[] profileData = new byte[cbProfileActual];
if (HRESULT.Failed(IWICCC.GetProfileBytes(
_colorContextHandle, cbProfileActual, profileData, out cbProfileActual))
)
{
return;
}
FromRawBytes(profileData, (int)cbProfileActual, /* dontThrowException = */ true);
}
break;
case IWICCC.WICColorContextType.WICColorContextExifColorSpace:
uint colorSpace;
if (HRESULT.Failed(IWICCC.GetExifColorSpace(_colorContextHandle, out colorSpace)))
{
return;
}
//
// From MSDN:
// "1" is sRGB. We will use our built-in sRGB profile.
// "2" is Adobe RGB. WIC says we should never see this because they are nonstandard and instead a
// real profile will be returned.
// "3-65534" is unused.
//
// From the Exif spec:
// B. Tag Relating to Color Space
// ColorSpace
//
// The color space information tag (ColorSpace) is always recorded as the color space specifier.
// Normally sRGB (=1) is used to define the color space based on the PC monitor conditions and environment. If a
// color space other than sRGB is used, Uncalibrated (=FFFF.H) is set. Image data recorded as Uncalibrated can be
// treated as sRGB when it is converted to Flashpix. On sRGB see Annex E.
// Tag = 40961 (A001.H)
// Type = SHORT
// Count = 1
// 1 = sRGB
// FFFF.H = Uncalibrated
//
// So for 65535 we will return sRGB since it is acceptible rather than having an invalid ColorContext. The Exif
// CC should always be the second one so the real one is given priority. Alternatively, we could ignore the
// uncalibrated CC but that would be a breaking change with 3.* (returning 1 instead of 2).
//
// If anything other than 1 or 65535 happens, _colorContextHelper will remain invalid and we will emulate
// the old crash behavior in OpenProfileStream().
//
if (colorSpace == 1 || colorSpace == 65535)
{
ResourceManager resourceManager = new ResourceManager(
_colorProfileResources, Assembly.GetAssembly(typeof(ColorContext))
);
byte[] sRGBProfile = (byte[])resourceManager.GetObject(_sRGBProfileName);
// The existing ColorContext has already been initialized as Exif so we can't initialize it again
// and instead must create a new one.
using (FactoryMaker factoryMaker = new FactoryMaker())
{
_colorContextHandle.Dispose();
_colorContextHandle = null;
if (HRESULT.Failed(UnsafeNativeMethodsMilCoreApi.WICCodec.CreateColorContext(
factoryMaker.ImagingFactoryPtr, out _colorContextHandle))
)
{
return;
}
if (HRESULT.Failed(IWICCC.InitializeFromMemory(
_colorContextHandle, sRGBProfile, (uint)sRGBProfile.Length))
)
{
return;
}
}
// Finally, fill in _colorContextHelper
FromRawBytes(sRGBProfile, sRGBProfile.Length, /* dontThrowException = */ true);
}
else if (Invariant.Strict)
{
Invariant.Assert(false, String.Format(CultureInfo.InvariantCulture, "IWICColorContext::GetExifColorSpace returned {0}.", colorSpace));
}
break;
default:
if (Invariant.Strict)
{
Invariant.Assert(false, "IWICColorContext::GetType() returned WICColorContextUninitialized.");
}
break;
}
// SECURITY NOTE: This constructor does not set a Uri because the profile comes from raw file
// data. Thus, we don't set _isProfileUriNotFromUser to true because we
// don't want get_ProfileUri to demand permission to return null.
Debug.Assert(_profileUri.Value == null);
}
