Я просто решить проблему с помощью последующего кода и шаги:
Первая моя ориентация устройства блокировки и мое приложение поддерживает только в портретной ориентации, так что я думаю, что я получаю только портретную ориентацию, однако я захват видео по ландшафтному режиму, так используя Core-motion
я получить ориентацию устройства, используя следующий код
#import <CoreMotion/CoreMotion.h>
@interface ViewController()
{
AVCaptureVideoOrientation orientationLast, orientationAfterProcess;
CMMotionManager *motionManager;
}
@implementation ViewController
- (void)initializeMotionManager{
motionManager = [[CMMotionManager alloc] init];
motionManager.accelerometerUpdateInterval = .2;
motionManager.gyroUpdateInterval = .2;
[motionManager startAccelerometerUpdatesToQueue:[NSOperationQueue currentQueue]
withHandler:^(CMAccelerometerData *accelerometerData, NSError *error) {
if (!error) {
[self outputAccelertionData:accelerometerData.acceleration];
}
else{
NSLog(@"%@", error);
}
}];
}
- (void)outputAccelertionData:(CMAcceleration)acceleration{
AVCaptureVideoOrientation orientationNew;
if (acceleration.x >= 0.75) {
orientationNew = AVCaptureVideoOrientationLandscapeLeft;
}
else if (acceleration.x <= -0.75) {
orientationNew =AVCaptureVideoOrientationLandscapeRight;
}
else if (acceleration.y <= -0.75) {
orientationNew =AVCaptureVideoOrientationPortrait;
}
else if (acceleration.y >= 0.75) {
orientationNew =AVCaptureVideoOrientationPortraitUpsideDown;
}
else {
// Consider same as last time
return;
}
if (orientationNew == orientationLast)
return;
orientationLast = orientationNew;
}
так на основе вращения устройства, что orientationLast
обновление ориентации устройства. после этого, когда я нажимаю кнопку для записи видео, я устанавливаю ориентацию AVCaptureConnection
.
AVCaptureConnection *CaptureConnection = [MovieFileOutput connectionWithMediaType:AVMediaTypeVideo];
if ([CaptureConnection isVideoOrientationSupported])
{
[CaptureConnection setVideoOrientation:orientationLast];
}
Теперь после съемки видео. Я сделал следующий код, и это работает отлично.
-(void)cropView:(NSURL*)outputfile
{
AVAsset *asset = [AVAsset assetWithURL:outputfile];
AVAssetTrack *clipVideoTrack = [[asset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
AVMutableVideoComposition* videoComposition = [AVMutableVideoComposition videoComposition];
videoComposition.frameDuration = CMTimeMake(1, 30);
AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
instruction.timeRange = CMTimeRangeMake(kCMTimeZero, CMTimeMakeWithSeconds(60, 30));
CGSize videoSize = [[[asset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] naturalSize];
float scaleFactor;
if (videoSize.width > videoSize.height) {
scaleFactor = videoSize.height/320;
}
else if (videoSize.width == videoSize.height){
scaleFactor = videoSize.height/320;
}
else{
scaleFactor = videoSize.width/320;
}
CGFloat cropOffX = 0;
CGFloat cropOffY = 0;
CGFloat cropWidth = 320 *scaleFactor;
CGFloat cropHeight = 320 *scaleFactor;
videoComposition.renderSize = CGSizeMake(cropWidth, cropHeight);
AVMutableVideoCompositionLayerInstruction* transformer = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:clipVideoTrack];
UIImageOrientation videoOrientation = [self getVideoOrientationFromAsset:asset];
CGAffineTransform t1 = CGAffineTransformIdentity;
CGAffineTransform t2 = CGAffineTransformIdentity;
switch (videoOrientation) {
case UIImageOrientationUp:
t1 = CGAffineTransformMakeTranslation(clipVideoTrack.naturalSize.height - cropOffX, 0 - cropOffY);
t2 = CGAffineTransformRotate(t1, M_PI_2);
break;
case UIImageOrientationDown:
t1 = CGAffineTransformMakeTranslation(0 - cropOffX, clipVideoTrack.naturalSize.width - cropOffY); // not fixed width is the real height in upside down
t2 = CGAffineTransformRotate(t1, - M_PI_2);
break;
case UIImageOrientationRight:
t1 = CGAffineTransformMakeTranslation(0 - cropOffX, 0 - cropOffY);
t2 = CGAffineTransformRotate(t1, 0);
break;
case UIImageOrientationLeft:
t1 = CGAffineTransformMakeTranslation(clipVideoTrack.naturalSize.width - cropOffX, clipVideoTrack.naturalSize.height - cropOffY);
t2 = CGAffineTransformRotate(t1, M_PI );
break;
default:
NSLog(@"no supported orientation has been found in this video");
break;
}
CGAffineTransform finalTransform = t2;
[transformer setTransform:finalTransform atTime:kCMTimeZero];
//add the transformer layer instructions, then add to video composition
instruction.layerInstructions = [NSArray arrayWithObject:transformer];
videoComposition.instructions = [NSArray arrayWithObject: instruction];
NSString *outputPath = [NSString stringWithFormat:@"%@%@", NSTemporaryDirectory(), @"video.mp4"];
NSURL *exportUrl = [NSURL fileURLWithPath:outputPath];
[[NSFileManager defaultManager] removeItemAtURL:exportUrl error:nil];
//Export
AVAssetExportSession *exporter = [[AVAssetExportSession alloc] initWithAsset:asset presetName:AVAssetExportPresetHighestQuality] ;
exporter.videoComposition = videoComposition;
exporter.outputURL = exportUrl;
exporter.outputFileType = AVFileTypeMPEG4;
[exporter exportAsynchronouslyWithCompletionHandler:^
{
dispatch_async(dispatch_get_main_queue(), ^{
//Call when finished
[self exportDidFinish:exporter];
});
}];
}
- (UIImageOrientation)getVideoOrientationFromAsset:(AVAsset *)asset
{
AVAssetTrack *videoTrack = [[asset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
CGSize size = [videoTrack naturalSize];
CGAffineTransform txf = [videoTrack preferredTransform];
if (size.width == txf.tx && size.height == txf.ty)
return UIImageOrientationLeft; //return UIInterfaceOrientationLandscapeLeft;
else if (txf.tx == 0 && txf.ty == 0)
return UIImageOrientationRight; //return UIInterfaceOrientationLandscapeRight;
else if (txf.tx == 0 && txf.ty == size.width)
return UIImageOrientationDown; //return UIInterfaceOrientationPortraitUpsideDown;
else
return UIImageOrientationUp; //return UIInterfaceOrientationPortrait;
}