通过AVAssetImageGenerator获取视频的UIImage时,如果视频是以纵向拍摄,我得到的图像会被旋转(尽管从技术上来说它们并没有被旋转)。如何判断视频的方向并正确旋转图像?
AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:url options:nil];
AVAssetImageGenerator *generate = [[AVAssetImageGenerator alloc] initWithAsset:asset];
NSError *err = NULL;
CMTime time = CMTimeMake(0, 60);
CGImageRef imgRef = [generate copyCGImageAtTime:time actualTime:NULL error:&err];
[generate release];
UIImage *currentImg = [[UIImage alloc] initWithCGImage:imgRef];