Configure Transforms

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VideoEditor SDK supports several configuration options for the TransformToolController allowing flexible adaptation to different needs and use cases. For a detailed explanation of how to configure different editor views, refer to this guide.

`allowedCropRatios`#

The default configuration includes a number of different crop aspect ratios users can choose from. In order to restrict those to specific aspect ratios only, for instance those used by social networks (e.g. Facebook, Twitter, Instagram, Flickr), we can specify aspect ratios as CropAspect object and give it the desired width and height. The localizedName argument to the CropAspect construtor allows using a custom name for the crop ratio. Note that setting the aspect ratio will not affect the resolution of the image.

`allowFreeCrop`#

While it is possible to configure the available preset aspect ratios for cropping, we can also disable free cropping to ensure that video will always choose one of the available aspect ratios by setting allowFreeCrop to false.

`showResetButton`#

When free crop is enabled, users need a way to reset the applied transform operations. In our example, since we are enforcing a certain set of aspect ratios, we can disable the reset button by setting showResetButton to false.

`outputScaling`#

Sometimes video resolution can't be represented in aspect ratio that is desired. That happen in cases where width and height aren't dividable by the selected aspect ratio widths and heights. For this purpose we have an option to scale the output resolution to match the selected ratio exactly. Default is set to .none which means that no output scaling will be performed. In our example we set it to .scaleUp, which means that the output resolution will be scaled up to the closest resolution that is dividable by the selected ratio.

✨Introduced in VideoEditor SDK v11.4.0

`forceCropMode`#

Since in this example we enforce a certain set of aspect ratios, we need to ensure that one of the crop options is selected before any other editing operations are applied. To this end we configure the VideoEditViewController by setting forceCropMode to true. This ensures that the transform tool is presented first if the selected video does not fit one of the allowed aspect ratios.


import UIKit
import VideoEditorSDK

class VideoTransformConfigurationSwift: Example, VideoEditViewControllerDelegate {
  override func invokeExample() {
    // Create a `Video` from a URL to a video in the app bundle.
    let video = Video(url: Bundle.main.url(forResource: "Skater", withExtension: "mp4")!)

    // Create a `Configuration` object.
    let configuration = Configuration { builder in
      // Configure the `TransformToolController` that lets the user
      // crop and rotate the video.
      builder.configureTransformToolController { options in
        // By default the editor has a lot of crop aspects enabled.
        // For this example only a couple are enabled, e.g. if you
        // only allow certain video aspects in your application.
        options.allowedCropRatios = [
          CropAspect(width: 1, height: 1),
          CropAspect(width: 16, height: 9, localizedName: "Landscape")
        ]

        // By default the editor allows to use a free crop ratio.
        // For this example this is disabled to ensure that the video
        // has a suitable ratio.
        options.allowFreeCrop = false

        // By default the editor shows the reset button which resets
        // the applied transform operations. In this example the button
        // is hidden since we are enforcing certain ratios and the user
        // can only select among them anyway.
        options.showResetButton = false

        // By default the editor doesn't apply any output scaling
        // ransform operations. In this example, we are using `scaleUp`
        // that will make sure that video output resolution exactly
        // matches selected aspect ratio.
        options.outputScaling = .scaleUp
      }

      // Configure the `VideoEditViewController`.
      builder.configureVideoEditViewController { options in
        // For this example the user is forced to crop the asset to one of
        // the allowed crop aspects specified above, before being able to use other
        // features of the editor. The transform tool will only be presented
        // if the video does not already fit one of those allowed aspect ratios.
        options.forceCropMode = true
      }
    }

    // Create and present the video editor. Make this class the delegate of it to handle export and cancelation.
    let videoEditViewController = VideoEditViewController(videoAsset: video, configuration: configuration)
    videoEditViewController.delegate = self
    videoEditViewController.modalPresentationStyle = .fullScreen
    presentingViewController?.present(videoEditViewController, animated: true, completion: nil)
  }

  // MARK: - VideoEditViewControllerDelegate

  func videoEditViewControllerShouldStart(_ videoEditViewController: VideoEditViewController, task: VideoEditorTask) -> Bool {
    // Implementing this method is optional. You can perform additional validation and interrupt the process by returning `false`.
    true
  }

  func videoEditViewControllerDidFinish(_ videoEditViewController: VideoEditViewController, result: VideoEditorResult) {
    // The user exported a new video successfully and the newly generated video is located at `result.output.url`. Dismissing the editor.
    presentingViewController?.dismiss(animated: true, completion: nil)
  }

  func videoEditViewControllerDidFail(_ videoEditViewController: VideoEditViewController, error: VideoEditorError) {
    // There was an error generating the video.
    print(error.localizedDescription)
    // Dismissing the editor.
    presentingViewController?.dismiss(animated: true, completion: nil)
  }

  func videoEditViewControllerDidCancel(_ videoEditViewController: VideoEditViewController) {
    // The user tapped on the cancel button within the editor. Dismissing the editor.
    presentingViewController?.dismiss(animated: true, completion: nil)
  }
}

Configure Transforms

allowedCropRatios#

allowFreeCrop#

showResetButton#

outputScaling#

forceCropMode#

`allowedCropRatios`#

`allowFreeCrop`#

`showResetButton`#

`outputScaling`#

`forceCropMode`#