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iphoneiosavfoundationavvideocomposition

Using AVVideoComposition for kens burn effect?

I'm current using AV Foundation to export images as videos. Now I want to add kens burn effect to these images when they are exported as a video.

As far as I know, this is achievable through AVVideoComposition but I'm not sure how to start.

Solution

  • AVMutableVideoComposition.animationTool (AVVideoCompositionCoreAnimationTool) looks promising.

    That and AVMutableVideoCompositionLayerInstruction's

    - (void)setTransformRampFromStartTransform:(CGAffineTransform)startTransform toEndTransform:(CGAffineTransform)endTransform timeRange:(CMTimeRange)timeRange;

    should be a good start, assuming the Ken Burn's effect can be implemented by interpolating affine transforms.