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Find the video orientation of an AVAsset. (Useful if you need to send the video to a remote server)
//
// AVAsset+VideoOrientation.h
//
// Created by Luca Bernardi on 19/09/12.
// Copyright (c) 2012 Luca Bernardi. All rights reserved.
//
#import <AVFoundation/AVFoundation.h>
typedef enum {
LBVideoOrientationUp, //Device starts recording in Portrait
LBVideoOrientationDown, //Device starts recording in Portrait upside down
LBVideoOrientationLeft, //Device Landscape Left (home button on the left side)
LBVideoOrientationRight, //Device Landscape Right (home button on the Right side)
LBVideoOrientationNotFound = 99 //An Error occurred or AVAsset doesn't contains video track
} LBVideoOrientation;
@interface AVAsset (VideoOrientation)
/**
Returns a LBVideoOrientation that is the orientation
of the iPhone / iPad whent starst recording
@return A LBVideoOrientation that is the orientation of the video
*/
@property (nonatomic, readonly) LBVideoOrientation videoOrientation;
@end
//
// AVAsset+VideoOrientation.m
//
// Created by Luca Bernardi on 19/09/12.
// Copyright (c) 2012 Luca Bernardi. All rights reserved.
//
#import "AVAsset+VideoOrientation.h"
static inline CGFloat RadiansToDegrees(CGFloat radians) {
return radians * 180 / M_PI;
};
@implementation AVAsset (VideoOrientation)
@dynamic videoOrientation;
- (LBVideoOrientation)videoOrientation
{
NSArray *videoTracks = [self tracksWithMediaType:AVMediaTypeVideo];
if ([videoTracks count] == 0) {
return LBVideoOrientationNotFound;
}
AVAssetTrack* videoTrack = [videoTracks objectAtIndex:0];
CGAffineTransform txf = [videoTrack preferredTransform];
CGFloat videoAngleInDegree = RadiansToDegrees(atan2(txf.b, txf.a));
LBVideoOrientation orientation = 0;
switch ((int)videoAngleInDegree) {
case 0:
orientation = LBVideoOrientationRight;
break;
case 90:
orientation = LBVideoOrientationUp;
break;
case 180:
orientation = LBVideoOrientationLeft;
break;
case -90:
orientation = LBVideoOrientationDown;
break;
default:
orientation = LBVideoOrientationNotFound;
break;
}
return orientation;
}
@end
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