Image.Save Method (Stream, ImageFormat)
Saves this image to the specified stream in the specified format.
Assembly: System.Drawing (in System.Drawing.dll)
You should avoid saving an image to the same stream that was used to construct it. Doing so might damage the stream.
The image must be saved to the stream at an offset of zero. If any additional data has been written to the stream before saving the image, the image data in the stream will be corrupted.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.