Scale the video up from a smaller size(Re-scale)

问题

I'm actually looking for is to not just the quality but resize the entire video to a greater resolution using the AV foundation. I have a videos in 320x240 and 176x144 in mp4 quality and I want to resize video upto size 1280x720, but AVAssetExportSession class not allow to scale the video up from a smaller size.

回答1:

try AVMutableVideoCompositionLayerInstruction and CGAffineTransform.

This code will help the understanding.

https://gist.github.com/zrxq/9817265

来源：https://stackoverflow.com/questions/33231675/scale-the-video-up-from-a-smaller-sizere-scale