Swift iOS - Наложение перетаскиваемого заголовка видео с перекосом на горизонтальное видео

Question

Я создаю приложение, которое позволяет пользователям выбирать видео из своей библиотеки и добавлять заголовок на экран, перетаскивать его туда, куда они хотят, в контейнер, в котором видео находится сзади, а заголовок сверху. Затем я хочу экспортировать это видео с надписью поверх видео.

Сначала я превращаю UIView с подписью в изображение, затем добавляю изображение в видео с помощью AVMutableComposition. Это работает с портретными видео, которые будут заполнять весь вид.

Проблема, с которой я сталкиваюсь, заключается в том, что в альбомной ориентации изображения заголовка разбиты. Мне нужно как-то всегда иметь видеокадр размером с вид заголовка и поместить видео поверх этого холста, а затем поместить заголовок поверх него.

import UIKit
import AVFoundation
import Photos

class VideoEditor {
    func mergeVideoCaption(fromVideoAt videoURL: URL, videoRect: CGRect, captionImage: UIImage, onComplete: @escaping (URL?) -> Void) {

        let asset = AVURLAsset(url: videoURL)
        let composition = AVMutableComposition()
        let captionSize = CGSize(width: captionImage.size.width * UIScreen.main.scale, height: captionImage.size.height * UIScreen.main.scale)
        //let captionSize = CGSize(width: captionImage.size.width, height: captionImage.size.height)

        //Create new mutable composition track from composition and create an asset track
        guard let compositionTrack = composition.addMutableTrack(withMediaType: .video, preferredTrackID: kCMPersistentTrackID_Invalid), let assetTrack = asset.tracks(withMediaType: .video).first else {
            print("Something is wrong with the asset.")
            onComplete(nil)
            return
        }


        do {
            //Set the time range for the composition video track based on asset duration
            //Insert asset track into the compositionTrack
            let timeRange = CMTimeRange(start: .zero, duration: asset.duration)
            try compositionTrack.insertTimeRange(timeRange, of: assetTrack, at: .zero)

            //create mutable audio track from composition and set time duration based on audio asset duration
            //Insert audio track into compositionAudioTrack
            if let audioAssetTrack = asset.tracks(withMediaType: .audio).first,
                let compositionAudioTrack = composition.addMutableTrack(withMediaType: .audio, preferredTrackID: kCMPersistentTrackID_Invalid) {
                try compositionAudioTrack.insertTimeRange(timeRange, of: audioAssetTrack, at: .zero)
            }
        } catch {
            print(error)
            onComplete(nil)
            return
        }

        compositionTrack.preferredTransform = assetTrack.preferredTransform
        let videoInfo = orientation(from: assetTrack.preferredTransform)

        let videoSize: CGSize
        if videoInfo.isPortrait {
            videoSize = CGSize(
                width: assetTrack.naturalSize.height,
                height: assetTrack.naturalSize.width)
        } else {
            videoSize = assetTrack.naturalSize
        }

        //Create layers
        let videoLayer = CALayer()
        //videoLayer.frame = CGRect(origin: .zero, size: videoSize)
        videoLayer.frame = CGRect(x: videoRect.origin.x * UIScreen.main.scale, y: videoRect.origin.y * UIScreen.main.scale, width: videoSize.width, height: videoSize.height)

        print("video size: \(videoSize)")
        print("video rect: \(videoRect)")
        print("caption rect: \(captionSize)")

        let overlayLayer = CALayer()
        overlayLayer.frame = CGRect(origin: .zero, size: videoSize)

        addImage(to: overlayLayer, image: captionImage, imageSize: videoSize)

        let outputLayer = CALayer()
        outputLayer.frame = CGRect(origin: .zero, size: videoSize)
        outputLayer.backgroundColor = GoinOnColors.black.cgColor

        let bgLayer = CALayer()
        bgLayer.frame = CGRect(origin: .zero, size: videoSize)
        bgLayer.backgroundColor = GoinOnColors.black.cgColor
        outputLayer.addSublayer(bgLayer)
        outputLayer.addSublayer(videoLayer)
        outputLayer.addSublayer(overlayLayer)

        let videoComposition = AVMutableVideoComposition()
        videoComposition.renderSize = videoSize
        videoComposition.frameDuration = CMTime(value: 1, timescale: 30)

        videoComposition.animationTool = AVVideoCompositionCoreAnimationTool(
            postProcessingAsVideoLayer: videoLayer,
            in: outputLayer)


        // Set the time range instruction for the video composition object
        let instruction = AVMutableVideoCompositionInstruction()
        instruction.timeRange = CMTimeRange(start: .zero, duration: composition.duration)
        videoComposition.instructions = [instruction]

        //
        let layerInstruction = compositionLayerInstruction(
            for: compositionTrack,
            assetTrack: assetTrack)
        instruction.layerInstructions = [layerInstruction]

        guard let export = AVAssetExportSession(asset: composition, presetName: AVAssetExportPresetHighestQuality) else {
            print("Cannot create export session.")
            onComplete(nil)
            return
        }

        let videoName = UUID().uuidString
        let exportURL = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(videoName).appendingPathExtension("mov")

        export.videoComposition = videoComposition
        export.outputFileType = .mov
        export.outputURL = exportURL

        export.exportAsynchronously {
            DispatchQueue.main.async {
                switch export.status {
                case .completed:
                    onComplete(exportURL)
                    //PHPhotoLibrary.shared().performChanges({
                    //PHAssetChangeRequest.creationRequestForAssetFromVideo(atFileURL: exportURL)
                    //})
                default:
                    print("Something went wrong during export.")
                    print(export.error ?? "unknown error")
                    onComplete(nil)
                    break
                }
            }
        }
    }

    private func addImage(to layer: CALayer, image: UIImage, imageSize: CGSize) {
        let imageLayer = CALayer()
        imageLayer.frame = CGRect(
            x: 0,
            y: 0,
            width: imageSize.width,
            height: imageSize.height)
        imageLayer.contents = image.cgImage
        layer.addSublayer(imageLayer)
    }

    private func orientation(from transform: CGAffineTransform) -> (orientation: UIImage.Orientation, isPortrait: Bool) {
        var assetOrientation = UIImage.Orientation.up
        var isPortrait = false
        if transform.a == 0 && transform.b == 1.0 && transform.c == -1.0 && transform.d == 0 {
            assetOrientation = .right
            isPortrait = true
        } else if transform.a == 0 && transform.b == -1.0 && transform.c == 1.0 && transform.d == 0 {
            assetOrientation = .left
            isPortrait = true
        } else if transform.a == 1.0 && transform.b == 0 && transform.c == 0 && transform.d == 1.0 {
            assetOrientation = .up
        } else if transform.a == -1.0 && transform.b == 0 && transform.c == 0 && transform.d == -1.0 {
            assetOrientation = .down
        }

        return (assetOrientation, isPortrait)
    }

    private func compositionLayerInstruction(for track: AVCompositionTrack, assetTrack: AVAssetTrack) -> AVMutableVideoCompositionLayerInstruction {
        let instruction = AVMutableVideoCompositionLayerInstruction(assetTrack: track)
        let transform = assetTrack.preferredTransform

        instruction.setTransform(transform, at: .zero)

        return instruction
    }

}

// Вот как Я называю это

let captionImage = UIImage(view: self.editCaptionMasterContainer)

                    let editor = VideoEditor()
                    editor.mergeVideoCaption(fromVideoAt: url, videoRect: self.videoPartial.avPlayerLayer!.videoRect, captionImage: captionImage)

Примеры снимков экрана