title: Which GPUImage fillmode for fullscreen on all iPhone size?
body: <p>I would like my GPUImageView (portrait, front camera) to be fullscreen whatever the phone screen size (from iPhone 4 to Iphone 6+). Ideally following an "Aspect fill" mode. </p>
  
  <p>Right now I have : </p>
  
  <pre><code>   _vidCamera = [[GPUImageVideoCamera alloc]
                    initWithSessionPreset:AVCaptureSessionPreset640x480
                    cameraPosition:AVCaptureDevicePositionBack];
      _vidCamera.outputImageOrientation = UIInterfaceOrientationPortrait;
  
      // View
      CGRect f = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);
      _filteredVideoView = [[GPUImageView alloc] initWithFrame:f];
  </code></pre>
  
  <p>Would kGPUImageFillModeStretch be enough ? Do I need to change the SessionPreset as well ? If I change the Session preset to something bigger than say the iPhone 4 can handle, will it cause trouble ? </p>
  
  <p>Sorry I can't test it myself because I don't own more than an iPhone 4. </p>