AVAsset Video Orientation and Camera Position.swift

extension AVAsset {
    
    func videoOrientation() -> (orientation: UIInterfaceOrientation, device: AVCaptureDevicePosition) {
        var orientation: UIInterfaceOrientation = .Unknown
        var device: AVCaptureDevicePosition = .Unspecified

        let tracks :[AVAssetTrack] = self.tracksWithMediaType(AVMediaTypeVideo)
        if let videoTrack = tracks.first {
            
            let t = videoTrack.preferredTransform
            
            if (t.a == 0 && t.b == 1.0 && t.d == 0) {
                orientation = .Portrait
                
                if t.c == 1.0 {
                    device = .Front
                } else if t.c == -1.0 {
                    device = .Back
                }
            }
            else if (t.a == 0 && t.b == -1.0 && t.d == 0) {
                orientation = .PortraitUpsideDown
                
                if t.c == -1.0 {
                    device = .Front
                } else if t.c == 1.0 {
                    device = .Back
                }
            }
            else if (t.a == 1.0 && t.b == 0 && t.c == 0) {
                orientation = .LandscapeRight
                
                if t.d == -1.0 {
                    device = .Front
                } else if t.d == 1.0 {
                    device = .Back
                }
            }
            else if (t.a == -1.0 && t.b == 0 && t.c == 0) {
                orientation = .LandscapeLeft
                
                if t.d == 1.0 {
                    device = .Front
                } else if t.d == -1.0 {
                    device = .Back
                }
            }
        }
        
        return (orientation, device)
    }
}

I updated this for current Swift (as at feb12-2017) and added a simple isPortrait bool to simply coding at my end.

https://gist.github.com/wdcurry/433dd1db8f315cf6edd9ff8d2ee6f411