Changing image size from stream
Here is how I do it:
byte[] imageBytes; //Of course image bytes is set to the bytearray of your image using (MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length)) { using (Image img = Image.FromStream(ms)) { int h = 100; int w = 100; using (Bitmap b = new Bitmap(img, new Size(w,h))) { using (MemoryStream ms2 = new MemoryStream()) { b.Save(ms2, System.Drawing.Imaging.ImageFormat.Jpeg); imageBytes = ms2.ToArray(); } } } } From there, I use a MemoryStream to upload. I use blob storage and use the UploadFromStreamAsync to load to blob.
This is a basic view of it.