Square cropping and fixing the video orientation in iOS

Question

I am capturing the video using UIImagePickerController, i can crop the video using the following code,

AVAsset *asset = [AVAsset assetWithURL:url];

//create         


        

Answer 1

I know this question is old but some people may still be wondering why some of the videos from the camera roll zoom in after they're cropped. I faced this problem and realized that the cropRect I was using as a frame was not scaled for the different aspect ratios of the video. To fix this problem I simply added the code below to crop the very top of the video into a square. If you want to change the position just change the y value but make sure to scale it according to the video. Luca Iaco provided some great code to get started with. I appreciate it!

CGSize videoSize = [[[asset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] naturalSize];
float scaleFactor;

if (videoSize.width > videoSize.height) {

    scaleFactor = videoSize.height/320;
}
else if (videoSize.width == videoSize.height){

    scaleFactor = videoSize.height/320;
}
else{
    scaleFactor = videoSize.width/320;
}

CGFloat cropOffX = 0;
CGFloat cropOffY = 0;
CGFloat cropWidth = 320 *scaleFactor;
CGFloat cropHeight = 320 *scaleFactor;