AVPlayer 将纵向视频旋转为横向

Question

我正在使用 AVcapture 录制视频并在 AVplayer 中播放。

    NSURL *videoUrl1 = [self.mediaInfo objectAtIndex:0];
AVURLAsset *videoAsset1 = [AVURLAsset URLAssetWithURL:videoUrl1 options:nil];
NSURL *videoUrl2 = [self.mediaInfo objectAtIndex:1];
AVURLAsset *videoAsset2 = [AVURLAsset URLAssetWithURL:videoUrl2 options:nil];
AVAssetTrack *videoTrack1 = [[videoAsset1 tracksWithMediaType:AVMediaTypeVideo]objectAtIndex:0];
AVAssetTrack *videoTrack2 = [[videoAsset2 tracksWithMediaType:AVMediaTypeVideo]objectAtIndex:0];

两个音轨放在一起：

     [compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, video1) ofTrack:videoTrack1 atTime:kCMTimeZero error:nil];
    [compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, video2) ofTrack:videoTrack2 atTime:(compositionVideoTrack.timeRange.duration) error:nil];

玩过：

    AVPlayerItem * newPlayerItem = [AVPlayerItem playerItemWithAsset:self.composition];
//newPlayerItem.videoComposition = mainCompositionInst;
self.mediaPlayer = [AVPlayer playerWithPlayerItem:newPlayerItem];
self.playerLayer = [AVPlayerLayer playerLayerWithPlayer:self.mediaPlayer];
[[self view].layer insertSublayer:self.playerLayer atIndex:0];
self.playerLayer.frame = [self view].layer.bounds;
self.playerLayer.videoGravity = AVLayerVideoGravityResizeAspectFill ;

[self playItem];

奇怪的是，对于完全相同的文件，初始 AVURLAsset 的 preferredTransform 与 A​​VAssetTrack 不同：

AVURLASSET

txf.a = 1.000000 txf.b = 0.000000 txf.c = 0.000000 txf.d = 1.000000 txf.tx = 0.000000 txf.ty = 0.000000

AVAssetTrack

txf.a = 0.000000 txf.b = 1.000000 txf.c = -1.000000 txf.d = 0.000000 txf.tx = 480.000000 txf.ty = 0.000000

任何帮助解决这个轮换将不胜感激， 提前致谢。

CL

Answer 1

创建视频合成

vidComposition = [AVMutableVideoComposition videoComposition];

设置vidComposition.instructions = mainInstruction (AVMutableVideoCompositionInstruction) 用 AVPlayer 编辑视频播放后

取消注释 newPlayerItem.videoComposition = mainCompositionInst; 并设置 vidComposition 而不是 mainCompositionInst。 newPlayerItem.videoComposition = vidComposition;

对于编辑视频，本教程可能会对您有所帮助。 raywenderlich.com/13418/how-to-play-record-edit-videos-in-io‌​s

我希望这会有所帮助。