silverlight 支持视频格式和图像格式

图像支持jpg png bmp的,不支持gif

视频

Windows Media	"353" - Microsoft Windows Media Audio v7 v8 and v9.x Standard (WMA Standard) "354" - Microsoft Windows Media Audio v9.x and v10 Professional (WMA Professional) WMV1 (Windows Media Video 7) WMV2 (Windows Media Video 8) WMV3 (Windows Media Video 9)
MP4	H.264 (ITU-T H.264 / ISO MPEG-4 AVC), AAC-LC
MP3	"85" - ISO MPEG-1 Layer III (MP3)