Step 1: Configuring the Request Engine

First, you need to tell your application that it will handle file-terminated requests differently. To do this, modify your web.config file by adding the following:

<configuration>
  <system.webServer>
    <handlers>
      ...
      <add name="JpegFileHandler" path="*.jpg" verb="GET" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
    </handlers>
  </system.webServer>
</configuration>

Step 2: Setting the Route

In your App_Start/RouteConfig.cs file, set up a route like this:

routes.MapRoute(
    name: "Fotos",
    url: "{foto}.jpg",
    defaults: new { controller = "Fotos", action = "Obter", foto = UrlParameter.Optional }
);

Step 3: RouteExistingFiles

This prevents files that already exist from being returned with the original name. You can comment on this line later.

routes.RouteExistingFiles = true;

routes.MapRoute(
    name: "Fotos",
    url: "{foto}.jpg",
    defaults: new { controller = "Fotos", action = "Obter", foto = UrlParameter.Optional }
);

Step 4: Controller Method

In FotosController , type the following Obter method:

public ActionResult Obter(string nomedoarquivo)
{
    // Execute aqui sua lógica para recuperar o arquivo.
    return File(variavelComAFotoComoByteArray, "image/jpeg");
}

variavelComAFotoComoByteArray must be byte[] .