feat(add reversal): ios (shahen94#157)

* adding reverse to process manager on ios

* ext react method for reverse

* adding credit

* removing excess

* removing more rubbish

* adding boomerang and reverse

* adding reverse and boomerang functions in swift

* adding credit

* adding credit

* fixing wrong c&p

* adding boomerang to bridge

* calling back error rather than just printing

* removing logs and commented code

Author: JoshM1994

ios/RNVideoProcessing/RNVideoTrimmer/AVUtilities.swift

@@ -0,0 +1,83 @@
+/*
+ * Credit to whydna and yayoc
+ * https://github.com/whydna/Reverse-AVAsset-Efficient
+ */
+
+import UIKit
+import AVFoundation
+
+class AVUtilities {
+  static func reverse(_ original: AVAsset, outputURL: URL, completion: @escaping (AVAsset) -> Void) {
+    
+    // Initialize the reader
+    
+    var reader: AVAssetReader! = nil
+    do {
+      reader = try AVAssetReader(asset: original)
+    } catch {
+      print("could not initialize reader.")
+      return
+    }
+    
+    guard let videoTrack = original.tracks(withMediaType: AVMediaTypeVideo).last else {
+      print("could not retrieve the video track.")
+      return
+    }
+    
+    let readerOutputSettings: [String: Any] = [kCVPixelBufferPixelFormatTypeKey as String : Int(kCVPixelFormatType_420YpCbCr8BiPlanarFullRange)]
+    let readerOutput = AVAssetReaderTrackOutput(track: videoTrack, outputSettings: readerOutputSettings)
+    reader.add(readerOutput)
+    
+    reader.startReading()
+    
+    // read in samples
+    
+    var samples: [CMSampleBuffer] = []
+    while let sample = readerOutput.copyNextSampleBuffer() {
+      samples.append(sample)
+    }
+    
+    // Initialize the writer
+    
+    let writer: AVAssetWriter
+    do {
+      writer = try AVAssetWriter(outputURL: outputURL, fileType: AVFileTypeQuickTimeMovie)
+    } catch let error {
+      fatalError(error.localizedDescription)
+    }
+    
+    let videoCompositionProps = [AVVideoAverageBitRateKey: videoTrack.estimatedDataRate]
+    let writerOutputSettings = [
+      AVVideoCodecKey: AVVideoCodecH264,
+      AVVideoWidthKey: videoTrack.naturalSize.width,
+      AVVideoHeightKey: videoTrack.naturalSize.height,
+      AVVideoCompressionPropertiesKey: videoCompositionProps
+      ] as [String : Any]
+    
+    let writerInput = AVAssetWriterInput(mediaType: AVMediaTypeVideo, outputSettings: writerOutputSettings)
+    writerInput.expectsMediaDataInRealTime = false
+    writerInput.transform = videoTrack.preferredTransform
+    
+    let pixelBufferAdaptor = AVAssetWriterInputPixelBufferAdaptor(assetWriterInput: writerInput, sourcePixelBufferAttributes: nil)
+    
+    writer.add(writerInput)
+    writer.startWriting()
+    writer.startSession(atSourceTime: CMSampleBufferGetPresentationTimeStamp(samples.first!))
+    
+    for (index, sample) in samples.enumerated() {
+      let presentationTime = CMSampleBufferGetPresentationTimeStamp(sample)
+      let imageBufferRef = CMSampleBufferGetImageBuffer(samples[samples.count - 1 - index])
+      while !writerInput.isReadyForMoreMediaData {
+        Thread.sleep(forTimeInterval: 0.1)
+      }
+      pixelBufferAdaptor.append(imageBufferRef!, withPresentationTime: presentationTime)
+      
+    }
+    
+    writer.finishWriting {
+      completion(AVAsset(url: outputURL))
+    }
+  }
+}
+
+

ios/RNVideoProcessing/RNVideoTrimmer/RNVideoTrimmer.swift

@@ -252,6 +252,132 @@ class RNVideoTrimmer: NSObject {
           }
       }
   }
+  
+  @objc func boomerang(_ source: String, options: NSDictionary, callback: @escaping RCTResponseSenderBlock) {
+    
+    let quality = ""
+    
+    let manager = FileManager.default
+    guard let documentDirectory = try? manager.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
+      else {
+        callback(["Error creating FileManager", NSNull()])
+        return
+    }
+    
+    let sourceURL = getSourceURL(source: source)
+    let firstAsset = AVAsset(url: sourceURL as URL)
+    
+    let mixComposition = AVMutableComposition()
+    let track = mixComposition.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: Int32(kCMPersistentTrackID_Invalid))
+
+    
+    var outputURL = documentDirectory.appendingPathComponent("output")
+    var finalURL = documentDirectory.appendingPathComponent("output")
+    do {
+      try manager.createDirectory(at: outputURL, withIntermediateDirectories: true, attributes: nil)
+      try manager.createDirectory(at: finalURL, withIntermediateDirectories: true, attributes: nil)
+      let name = randomString()
+      outputURL = outputURL.appendingPathComponent("\(name).mp4")
+      finalURL = finalURL.appendingPathComponent("\(name)merged.mp4")
+    } catch {
+      callback([error.localizedDescription, NSNull()])
+      print(error)
+    }
+    
+    //Remove existing file
+    _ = try? manager.removeItem(at: outputURL)
+    _ = try? manager.removeItem(at: finalURL)
+    
+    let useQuality = getQualityForAsset(quality: quality, asset: firstAsset)
+    
+//    print("RNVideoTrimmer passed quality: \(quality). useQuality: \(useQuality)")
+    
+    AVUtilities.reverse(firstAsset, outputURL: outputURL, completion: { [unowned self] (reversedAsset: AVAsset) in
+      
+      
+      let secondAsset = reversedAsset
+      
+      // Credit: https://www.raywenderlich.com/94404/play-record-merge-videos-ios-swift
+      do {
+        try track.insertTimeRange(CMTimeRangeMake(kCMTimeZero, firstAsset.duration), of: firstAsset.tracks(withMediaType: AVMediaTypeVideo)[0], at: kCMTimeZero)
+      } catch _ {
+        callback( ["Failed: Could not load 1st track", NSNull()] )
+        return
+      }
+      
+      do {
+        try track.insertTimeRange(CMTimeRangeMake(kCMTimeZero, secondAsset.duration), of: secondAsset.tracks(withMediaType: AVMediaTypeVideo)[0], at: mixComposition.duration)
+      } catch _ {
+        callback( ["Failed: Could not load 2nd track", NSNull()] )
+        return
+      }
+      
+      
+      guard let exportSession = AVAssetExportSession(asset: mixComposition, presetName: useQuality) else {
+        callback(["Error creating AVAssetExportSession", NSNull()])
+        return
+      }
+      exportSession.outputURL = NSURL.fileURL(withPath: finalURL.path)
+      exportSession.outputFileType = AVFileTypeMPEG4
+      exportSession.shouldOptimizeForNetworkUse = true
+      let startTime = CMTime(seconds: Double(0), preferredTimescale: 1000)
+      let endTime = CMTime(seconds: mixComposition.duration.seconds, preferredTimescale: 1000)
+      let timeRange = CMTimeRange(start: startTime, end: endTime)
+      
+      exportSession.timeRange = timeRange
+      
+      exportSession.exportAsynchronously{
+        switch exportSession.status {
+        case .completed:
+          callback( [NSNull(), finalURL.absoluteString] )
+          
+        case .failed:
+          callback( ["Failed: \(exportSession.error)", NSNull()] )
+          
+        case .cancelled:
+          callback( ["Cancelled: \(exportSession.error)", NSNull()] )
+          
+        default: break
+        }
+      }
+    })
+  }
+  
+  @objc func reverse(_ source: String, options: NSDictionary, callback: @escaping RCTResponseSenderBlock) {
+    
+    let quality = ""
+    
+    let manager = FileManager.default
+    guard let documentDirectory = try? manager.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
+      else {
+        callback(["Error creating FileManager", NSNull()])
+        return
+    }
+    
+    let sourceURL = getSourceURL(source: source)
+    let asset = AVAsset(url: sourceURL as URL)
+    
+    var outputURL = documentDirectory.appendingPathComponent("output")
+    do {
+      try manager.createDirectory(at: outputURL, withIntermediateDirectories: true, attributes: nil)
+      let name = randomString()
+      outputURL = outputURL.appendingPathComponent("\(name).mp4")
+    } catch {
+      callback([error.localizedDescription, NSNull()])
+      print(error)
+    }
+    
+    //Remove existing file
+    _ = try? manager.removeItem(at: outputURL)
+    
+    let useQuality = getQualityForAsset(quality: quality, asset: asset)
+    
+    print("RNVideoTrimmer passed quality: \(quality). useQuality: \(useQuality)")
+    
+    AVUtilities.reverse(asset, outputURL: outputURL, completion: { [unowned self] (asset: AVAsset) in
+      callback( [NSNull(), outputURL.absoluteString] )
+    })
+  }
 
   @objc func compress(_ source: String, options: NSDictionary, callback: @escaping RCTResponseSenderBlock) {
 

ios/RNVideoProcessing/RNVideoTrimmer/RNVideoTrimmerBridge.m

@@ -11,6 +11,8 @@ @interface RCT_EXTERN_MODULE(RNVideoTrimmer, NSObject)
 
 RCT_EXTERN_METHOD(getAssetInfo:(NSString *)source callback:(RCTResponseSenderBlock)callback);
 RCT_EXTERN_METHOD(trim:(NSString *)source options:(NSDictionary *)options callback:(RCTResponseSenderBlock)callback);
+RCT_EXTERN_METHOD(reverse:(NSString *)source options:(NSDictionary *)options callback:(RCTResponseSenderBlock)callback);
+RCT_EXTERN_METHOD(boomerang:(NSString *)source options:(NSDictionary *)options callback:(RCTResponseSenderBlock)callback);
 RCT_EXTERN_METHOD(compress:(NSString *)source options:(NSDictionary *)options callback:(RCTResponseSenderBlock)callback);
 RCT_EXTERN_METHOD(getPreviewImageAtPosition:(NSString *)source atTime:(float *)atTime maximumSize:(NSDictionary *)maximumSize format:(NSString *)format callback:(RCTResponseSenderBlock)callback);
 RCT_EXTERN_METHOD(crop:(NSString *)source options:(NSDictionary *)options callback:(RCTResponseSenderBlock)callback);

lib/ProcessingManager/ProcessingManager.ios.js

@@ -25,6 +25,30 @@ export class ProcessingManager {
     });
   }
 
+    static reverse(source: sourceType, options: trimOptions = {}): Promise<string> {
+        const actualSource: string = getActualSource(source);
+        return new Promise((resolve, reject) => {
+            RNVideoTrimmer.reverse(actualSource, options, (err: Object<*>, output: string) => {
+                if (err) {
+                    return reject(err);
+                }
+                return resolve(output);
+            });
+        });
+    }
+
+    static boomerang(source: sourceType, options: trimOptions = {}): Promise<string> {
+        const actualSource: string = getActualSource(source);
+        return new Promise((resolve, reject) => {
+            RNVideoTrimmer.boomerang(actualSource, options, (err: Object<*>, output: string) => {
+                if (err) {
+                    return reject(err);
+                }
+                return resolve(output);
+            });
+        });
+    }
+
   static getPreviewForSecond(
     source: sourceType,
     forSecond: ?number = 0,