Change Image extension using FileUpload control in ASP.Net MVC

How to change image extension to jpeg format after uploading via uploadfile control and save it as jpeg format.

        [HttpGet]
		public ActionResult UploadFile()
		{
			return View();
		}
		[HttpPost]
		public ActionResult UploadFile(HttpPostedFileBase file)
		{
			try
			{
				if (Request.Files.Count > 0)
				{
					HttpPostedFileBase File = Request.Files[0];
					if (File != null && File.ContentLength > 0)
					{
						if (Path.GetExtension(file.FileName) != "jpeg")
						{
							string trailingPath = Path.GetFileName(file.FileName);
							string fullPath = Server.MapPath(file.FileName.Replace("png","jpeg"));
							file.SaveAs(fullPath);

@{
	ViewBag.Title = "UploadFile";
}

<h2>UploadFile</h2>

@using (Html.BeginForm("UploadFile", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{

<div>
	<input id="File" name="File" type="file" style="width:100%" accept="image/*" />
	<input type="submit" value="Upload" />
	@ViewBag.Message
</div>
}