Ios AVAssetTrack preferredTransform始终返回横向
我有一个录制视频的应用程序 要处理电话轮换,我有以下代码:Ios AVAssetTrack preferredTransform始终返回横向,ios,avfoundation,Ios,Avfoundation,我有一个录制视频的应用程序 要处理电话轮换,我有以下代码: // called on phone rotation AVCaptureConnection *previewLayerConnection = [[self previewLayer] connection]; if ([previewLayerConnection isVideoOrientationSupported]) { [previewLayerConnection setVideo
// called on phone rotation
AVCaptureConnection *previewLayerConnection = [[self previewLayer] connection];
if ([previewLayerConnection isVideoOrientationSupported]) {
[previewLayerConnection setVideoOrientation:[self getVideoOrientation]];
}
和getVideoOrientation功能:
- (AVCaptureVideoOrientation) getVideoOrientation {
UIInterfaceOrientation deviceOrientation = [[UIDevice currentDevice] orientation];
AVCaptureVideoOrientation newOrientation = AVCaptureVideoOrientationPortrait;
switch (deviceOrientation) {
case UIInterfaceOrientationPortrait:
NSLog(@"UIInterfaceOrientationPortrait");
newOrientation = AVCaptureVideoOrientationPortrait;
break;
case UIInterfaceOrientationLandscapeLeft:
NSLog(@"UIInterfaceOrientationLandscapeRight");
newOrientation = AVCaptureVideoOrientationLandscapeLeft;
break;
case UIInterfaceOrientationLandscapeRight:
NSLog(@"UIInterfaceOrientationLandscapeLeft");
newOrientation = AVCaptureVideoOrientationLandscapeRight;
break;
default:
NSLog(@"default");
newOrientation = AVCaptureVideoOrientationPortrait;
break;
}
return newOrientation;
}
应用程序的这一部分工作正常(我在任何设备上都可以看到视频)。
但当我尝试制作缩略图(或播放视频)时,我遇到了问题
正如我在其他问题中所读到的,我对每首曲目都做了以下操作:
AVAssetTrack* videoTrack = [[asset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
CGAffineTransform txf = [videoTrack preferredTransform];
CGFloat videoAngleInDegree = RadiansToDegrees(atan2(txf.b, txf.a));
if (txf.a == 0 && txf.b == 1.0 && txf.c == -1.0 && txf.d == 0) {
thumbOrientation = UIImageOrientationLeft;
}
if (txf.a == 0 && txf.b == -1.0 && txf.c == 1.0 && txf.d == 0) {
thumbOrientation = UIImageOrientationRight;
}
if (txf.a == 1.0 && txf.b == 0 && txf.c == 0 && txf.d == 1.0) {
thumbOrientation = UIImageOrientationUp;
}
if (txf.a == -1.0 && txf.b == 0 && txf.c == 0 && txf.d == -1.0) {
thumbOrientation = UIImageOrientationDown;
}
UIImage *image = [UIImage imageWithCGImage:im scale:1.0 orientation:thumbOrientation];
我有两个示例文件:1-右横向,2-左横向。我希望它们在上面的代码中有不同的方向,但出乎意料的是它们有相同的方向(而videoAngleInDegree对它们来说都是相同的)
有什么解决办法吗?你确定它工作正常吗?那里的
getVideoOrientation
看起来不对——AVCapture和UIDevice对于横向左侧和右侧的含义相反
下面是一个来自的正确实现--检查下面的讨论,看看它是否有帮助
- (void)deviceOrientationDidChange{
UIDeviceOrientation deviceOrientation = [[UIDevice currentDevice] orientation];
AVCaptureVideoOrientation newOrientation;
if (deviceOrientation == UIDeviceOrientationPortrait){
NSLog(@"deviceOrientationDidChange - Portrait");
newOrientation = AVCaptureVideoOrientationPortrait;
}
else if (deviceOrientation == UIDeviceOrientationPortraitUpsideDown){
NSLog(@"deviceOrientationDidChange - UpsideDown");
newOrientation = AVCaptureVideoOrientationPortraitUpsideDown;
}
// AVCapture and UIDevice have opposite meanings for landscape left and right (AVCapture orientation is the same as UIInterfaceOrientation)
else if (deviceOrientation == UIDeviceOrientationLandscapeLeft){
NSLog(@"deviceOrientationDidChange - LandscapeLeft");
newOrientation = AVCaptureVideoOrientationLandscapeRight;
}
else if (deviceOrientation == UIDeviceOrientationLandscapeRight){
NSLog(@"deviceOrientationDidChange - LandscapeRight");
newOrientation = AVCaptureVideoOrientationLandscapeLeft;
}
else if (deviceOrientation == UIDeviceOrientationUnknown){
NSLog(@"deviceOrientationDidChange - Unknown ");
newOrientation = AVCaptureVideoOrientationPortrait;
}
else{
NSLog(@"deviceOrientationDidChange - Face Up or Down");
newOrientation = AVCaptureVideoOrientationPortrait;
}
[self setOrientation:newOrientation];
}