Ios 如何缩放CALayer以适应视频层
我和CALayer有问题。关键是我想在这部电影上保留一些视图。基本上,我正试图通过CALayer来完成。一切正常,应用程序导出带有层的电影,但带有视图的层比视频帧小 我试图手动缩放图层,但根本不像屏幕上显示的那个样。如果我在电影中把UIView移得更高,它会变得更高 视频具有全高清帧,UIView的层次取决于用户在屏幕上的放置方式 问题是: -如何以更好的视网膜质量呈现UIView上下文Ios 如何缩放CALayer以适应视频层,ios,objective-c,iphone,swift,uiview,Ios,Objective C,Iphone,Swift,Uiview,我和CALayer有问题。关键是我想在这部电影上保留一些视图。基本上,我正试图通过CALayer来完成。一切正常,应用程序导出带有层的电影,但带有视图的层比视频帧小 我试图手动缩放图层,但根本不像屏幕上显示的那个样。如果我在电影中把UIView移得更高,它会变得更高 视频具有全高清帧,UIView的层次取决于用户在屏幕上的放置方式 问题是: -如何以更好的视网膜质量呈现UIView上下文 如何缩放层以完全适合视频 代码如下: VideoSaver.saveVideo(videoAsset!)
- 如何缩放层以完全适合视频
VideoSaver.saveVideo(videoAsset!) { (composition, size) in
////////////////
//Parent Layer//
////////////////
let parentLayer = CALayer()
parentLayer.frame = CGRectMake(0, 0, size.width, size.height)
/////////
//Sizes//
/////////
let xScaleValue = CGRectGetWidth(parentLayer.frame)/CGRectGetWidth(self.view.frame)
let yScaleValue = CGRectGetHeight(parentLayer.frame)/CGRectGetHeight(self.view.frame)
///////////////
//Video Layer//
///////////////
let videoLayer = CALayer()
videoLayer.frame = CGRectMake(0, 0, size.width, size.height)
//////////////////
//Captions Layer//
//////////////////
//Creating UIImage from Captions
UIGraphicsBeginImageContext(CGSizeMake(self.captionsTextView.bounds.size.width, self.captionsTextView.bounds.size.height+20))
let currentContext = UIGraphicsGetCurrentContext()
CGContextTranslateCTM(currentContext, 0, 16)
self.captionsTextView.layer.renderInContext(currentContext!)
let captionTextViewImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
let captionsOverlayLayer = CALayer()
captionsOverlayLayer.contents = captionTextViewImage.CGImage
captionsOverlayLayer.frame = CGRectMake(self.captionsTextView.frame.origin.x * xScaleValue,
(size.height - ((self.captionsTextView.frame.origin.y - 20) * yScaleValue)),
CGRectGetWidth(self.captionsTextView.frame) * xScaleValue,
(CGRectGetHeight(self.captionsTextView.frame)+20) * yScaleValue)
captionsOverlayLayer.masksToBounds = true
///////////////////
//TagFilter Layer//
///////////////////
UIGraphicsBeginImageContext(self.tagView.bounds.size)
self.tagView.layer.renderInContext(UIGraphicsGetCurrentContext()!)
let tagViewImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
let tagOverlayLayer = CALayer()
tagOverlayLayer.contents = tagViewImage.CGImage
tagOverlayLayer.frame = CGRectMake(self.tagView.frame.origin.x * xScaleValue,
(size.height - ((self.tagView.frame.origin.y) * yScaleValue)),
CGRectGetWidth(self.tagView.frame) * xScaleValue,
(CGRectGetHeight(self.tagView.frame)) * yScaleValue)
///////////////////////////////////////////////
parentLayer.addSublayer(videoLayer)
parentLayer.addSublayer(captionsOverlayLayer)
parentLayer.addSublayer(tagOverlayLayer)
///////////////
//Composition//
///////////////
composition.animationTool = AVVideoCompositionCoreAnimationTool.init(postProcessingAsVideoLayer: videoLayer, inLayer: parentLayer)
}
我很乐意提供帮助:)如果问题在于图层显示的图像分辨率,则:
- 这是您的第一个错误:
。始终调用UIGraphicsBeginImageContext
和第三个参数UIGraphicsBeginImageContextWithOptions
,或显式解析0
- 第二个错误是您从未设置CALayer的
contentsCale
UIView
都放在一个UIView
中。从这个ui视图
我创建了图层并将其缩放到视频大小。如果有人遇到同样的问题,则会有一个代码:
VideoSaver.saveVideo(videoAsset!)
{
(composition, size) in
////////////////
//Parent Layer//
////////////////
let parentLayer = CALayer()
parentLayer.frame = CGRectMake(0, 0, size.width, size.height)
///////////////
//Video Layer//
///////////////
let videoLayer = CALayer()
videoLayer.frame = CGRectMake(0, 0, size.width, size.height)
///////////////////////
//Effect Layout Layer//
///////////////////////
UIGraphicsBeginImageContextWithOptions(self.effectLayoutView.bounds.size, false, 0.0)
self.effectLayoutView.layer.renderInContext(UIGraphicsGetCurrentContext()!)
let effectLayoutViewImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
let effectOverlayLayer = CALayer()
effectOverlayLayer.contents = effectLayoutViewImage.CGImage
effectOverlayLayer.frame = CGRectMake(0, 0, size.width, size.height)
effectOverlayLayer.masksToBounds = true
///////////////////////////////////////////////
parentLayer.addSublayer(videoLayer)
parentLayer.addSublayer(effectOverlayLayer)
///////////////
//Composition//
///////////////
composition.animationTool = AVVideoCompositionCoreAnimationTool.init(postProcessingAsVideoLayer: videoLayer, inLayer: parentLayer)
}
如果我理解正确,我必须添加到每个CALayer
contentScale=self.myView.layer.contentsScale
?我还更改了UIGraphicsBeginImageContextWithOptions(CGSizeMake(self.captionsTextView.bounds.size.width,self.captionsTextView.bounds.size.height+20),false,0.0)
。不幸的是,我不知道如何将层调整为视频大小:(好吧,这里已经详细介绍了您正在做的事情;例如,请参阅教程,以及类似我遇到相同问题的教程,父层的子层没有根据视频层大小调整大小。您能帮我吗?您已经添加了parentLayer.addSublayer(videoLayer)parentLayer.addSublayer(effectoverlayer)为什么?