ios在另一个视频上叠加Alpha通道视频

Question

I have been trying to create a video template which uses alpha channel video overlayed on the mp4 videos and images.

This is how I need to create a video http://viewptch.ptchcdn.com/rendered/52b28a9f8d4f980f3a3f99c3_cb44bf2b/52b28a9f8d4f980f3a3f99c3_lrg_main_main.mov For overlaying alpha video on another videos, I have used AVAnimator, I was succeeded for playing a preview using AVFoundation, AVSynchronizedLayer and AVAnimator.

When rendering video from composition, frames of alpha channel videos renders very slowly.

I need to create a video with alpha channel video on top of another video.

Can any one please suggest me what are the possible ways to render a video like http://viewptch.ptchcdn.com/rendered/52b28a9f8d4f980f3a3f99c3_cb44bf2b/52b28a9f8d4f980f3a3f99c3_lrg_main_main.mov ?

Answer 1

You mention that you have looked at AVAnimator, did you download the KittyBoom example project and try it out? The specifics of how it works are detailed in this post . One thing to note is that when you build and run on the device, you need to turn Debug mode off otherwise it will not execute quickly because a number of extra checks are done in debug mode. Also, you have to make sure to test on the actual device, the simulator is not a good measure of performance on a real device. Performance is a key problem with video that contains an alpha channel as iOS does not support video with an alpha channel by default.