ios - 我想在不使用任何第三方框架的情况下将过滤器应用于录制的视频。我曾尝试将 CIfilter 用于 CAlayer 但它不起作用

Question

我想在不使用任何第三方框架的情况下将过滤器应用于预录视频我该怎么做。我曾尝试将 CIfilter 用于 CAlayer 但它不起作用。这是我的代码:

 CALayer *effectlayer=[CALayer layer];
    CIFilter *filter = [CIFilter filterWithName:@"CISepiaTone"
                                  keysAndValues: kCIInputImageKey,effectlayer,
                        @"inputIntensity", @.5, nil];


    [effectlayer setFilters:[NSArray arrayWithObjects:filter, nil]];

    CALayer *parentLayer = [CALayer layer];
    CALayer *videoLayer=[CALayer layer];
    parentLayer.frame = CGRectMake(0, 0, size.width, size.height);
    videoLayer.frame = CGRectMake(0, 0, size.width, size.height);
    [parentLayer addSublayer:videoLayer];
    [parentLayer addSublayer:overlayLayer];

    [parentLayer addSublayer:overlayLayero];
    [parentLayer addSublayer:effectlayer];

Answer 1

这是我的答案代码:

// 1 - set up the overlay
CALayer *overlayLayer = [CALayer layer];
UIImage *overlayImage = nil;


overlayImage = [UIImage imageNamed:@"your Image name"];


[overlayLayer setContents:(id)[overlayImage CGImage]];
overlayLayer.frame = CGRectMake(0, 0, size.width, size.height);
[overlayLayer setMasksToBounds:YES];

// 2 - set up the parent layer
CALayer *parentLayer = [CALayer layer];
CALayer *videoLayer = [CALayer layer];
parentLayer.frame = CGRectMake(0, 0, size.width, size.height);
videoLayer.frame = CGRectMake(0, 0, size.width, size.height);
[parentLayer addSublayer:videoLayer];
[parentLayer addSublayer:overlayLayer];

// composiontion is instance of your AVMutableVideoComposition
composition.animationTool = [AVVideoCompositionCoreAnimationTool
                             videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:parentLayer];