/// <summary>
/// Converts the image to a png stream, which can be assigned to
/// a silverlight image control as image source and applies the specified
/// filter before converting the image.
/// </summary>
/// <param name="image">The image, which should be converted. Cannot be null
/// (Nothing in Visual Basic).</param>
/// <param name="filter">The filter, which should be applied before converting the
/// image or null, if no filter should be applied to. Cannot be null.</param>
/// <returns>The resulting stream.</returns>
/// <exception cref="ArgumentNullException">
/// <para><paramref name="image"/> is null (Nothing in Visual Basic).</para>
/// <para>- or -</para>
/// <para><paramref name="filter"/> is null (Nothing in Visual Basic).</para>
/// </exception>
public static Stream ToStream(this ExtendedImage image, IImageFilter filter)
{
Contract.Requires <ArgumentNullException>(image != null, "Image cannot be null.");
Contract.Requires <ArgumentException>(image.IsFilled, "Image has not been loaded.");
MemoryStream memoryStream = new MemoryStream();
try
{
ExtendedImage temp = image;
if (filter != null)
{
temp = image.Clone();
filter.Apply(temp, image, temp.Bounds);
}
PngEncoder encoder = new PngEncoder();
encoder.IsWritingUncompressed = true;
encoder.Encode(temp, memoryStream);
memoryStream.Seek(0, SeekOrigin.Begin);
}
catch
{
if (memoryStream != null)
{
memoryStream.Dispose();
memoryStream = null;
}
throw;
}
return(memoryStream);
}
