Size of Image object

[philip]

Is there a property of the object Image which gives the size (length) of an
image in a given ImageFormat ?
I can know its length if I use :
Image.Save ("xxx.jpg", System.Drawing. Imaging.ImageFo rmat.Jpeg)
Dim file as New FileInfo ("xxx.jpg")
fileLength=file .Length

But is it possible to know this length BEFORE I save the image in the chosen
ImageFormat ?

Thanks for your help