WebPicture.Constructor(data as String, FileName as String)

From Xojo Documentation

Constructor
WebPicture.Constructor(data as String, fileName as String)

Creates a WebPicture from the passed string data using the specified fileName.

Example

If you have the picture data available as a String, you can use it to create a WebPicture:

Dim myPicture As New WebPicture(pictureData, "MyPicture.png")