我正在尝试从手机库中的 MOV 类型视频中删除音轨。我知道我可以在播放时将音频静音，但我计划上传用户视频，并且将音频取出并减小文件大小才有意义。
我尝试将 obj-c 代码从 THIS ANSWER 转换为 swift，但我要么搞砸了转换，要么就是没有从文件中取出音频。
任何帮助将不胜感激。
【问题讨论】：
标签： ios swift audio video avfoundation
最受好评的答案对我不起作用 + 我遇到了视频轮播问题。我最终通过添加参数muteSound: Bool 来修改我的视频压缩方法。
我使用2300000 的比特率来保持视频看起来不错，但尺寸比原始视频小 3-4 倍。
我将保持问题的开放性并将投票最多的问题标记为正确。也许有人可以想出一些更简单的东西。
func compressVideo(inputURL: NSURL, outputURL: NSURL, bitRate: Int, muteSound: Bool, onDone: () -> ()) {
let videoAsset = AVURLAsset(URL: inputURL, options: nil)
let videoTrack = videoAsset.tracksWithMediaType(AVMediaTypeVideo)[0]
let videoSize = videoTrack.naturalSize
let videoWriterCompressionSettings = [
AVVideoAverageBitRateKey: bitRate
]
let videoWriterSettings:[String : AnyObject] = [
AVVideoCodecKey : AVVideoCodecH264,
AVVideoCompressionPropertiesKey : videoWriterCompressionSettings,
AVVideoWidthKey : Int(videoSize.width),
AVVideoHeightKey : Int(videoSize.height)
]
let videoWriterInput = AVAssetWriterInput(mediaType: AVMediaTypeVideo, outputSettings: videoWriterSettings)
videoWriterInput.expectsMediaDataInRealTime = true
videoWriterInput.transform = videoTrack.preferredTransform
let videoWriter = try! AVAssetWriter(URL: outputURL, fileType: AVFileTypeQuickTimeMovie)
videoWriter.addInput(videoWriterInput)
let videoReaderSettings:[String : AnyObject] = [
kCVPixelBufferPixelFormatTypeKey as String: Int(kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange)
]
let videoReaderOutput = AVAssetReaderTrackOutput(track: videoTrack, outputSettings: videoReaderSettings)
let videoReader = try! AVAssetReader(asset: videoAsset)
videoReader.addOutput(videoReaderOutput)
let audioWriterInput = AVAssetWriterInput(mediaType: AVMediaTypeAudio, outputSettings: nil)
audioWriterInput.expectsMediaDataInRealTime = false
videoWriter.addInput(audioWriterInput)
let audioTrack = videoAsset.tracksWithMediaType(AVMediaTypeAudio)[0]
let audioReaderOutput = AVAssetReaderTrackOutput(track: audioTrack, outputSettings: nil)
let audioReader = try! AVAssetReader(asset: videoAsset)
if muteSound == false {
audioReader.addOutput(audioReaderOutput)
}
videoWriter.startWriting()
videoReader.startReading()
videoWriter.startSessionAtSourceTime(kCMTimeZero)
let processingQueue = dispatch_queue_create("processingQueue1", nil)
videoWriterInput.requestMediaDataWhenReadyOnQueue(processingQueue, usingBlock: {() -> Void in
while videoWriterInput.readyForMoreMediaData {
let sampleBuffer:CMSampleBuffer? = videoReaderOutput.copyNextSampleBuffer()
if videoReader.status == .Reading && sampleBuffer != nil {
videoWriterInput.appendSampleBuffer(sampleBuffer!)
} else {
videoWriterInput.markAsFinished()
if videoReader.status == .Completed {
if muteSound {
// return without sound
videoWriter.finishWritingWithCompletionHandler({() -> Void in
onDone()
})
} else {
audioReader.startReading()
videoWriter.startSessionAtSourceTime(kCMTimeZero)
let processingQueue = dispatch_queue_create("processingQueue2", nil)
audioWriterInput.requestMediaDataWhenReadyOnQueue(processingQueue, usingBlock: {() -> Void in
while audioWriterInput.readyForMoreMediaData {
let sampleBuffer:CMSampleBufferRef? = audioReaderOutput.copyNextSampleBuffer()
if audioReader.status == .Reading && sampleBuffer != nil {
audioWriterInput.appendSampleBuffer(sampleBuffer!)
} else {
audioWriterInput.markAsFinished()
if audioReader.status == .Completed {
videoWriter.finishWritingWithCompletionHandler({() -> Void in
onDone()
})
}
}
}
})
}
}
}
}
})
}
【讨论】：
你可以试试这个
NSString * initPath1 = VideoLocalPath;
AVMutableComposition *composition = [AVMutableComposition composition];
NSString *inputVideoPath = initPath1;
AVURLAsset * sourceAsset = [[AVURLAsset alloc] initWithURL:[NSURL fileURLWithPath:inputVideoPath] options:nil];
AVMutableCompositionTrack *compositionVideoTrack = [composition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
BOOL ok = NO;
AVAssetTrack * sourceVideoTrack = [[sourceAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
CMTimeRange x = CMTimeRangeMake(kCMTimeZero, [sourceAsset duration]);
ok = [compositionVideoTrack insertTimeRange:x ofTrack:sourceVideoTrack atTime:kCMTimeZero error:nil];
if([[NSFileManager defaultManager] fileExistsAtPath:initPath1]) {
[[NSFileManager defaultManager] removeItemAtPath:initPath1 error:nil];
}
NSURL *url = [[NSURL alloc] initFileURLWithPath: initPath1];
AVAssetExportSession *exporter = [[AVAssetExportSession alloc] initWithAsset:composition presetName:AVAssetExportPresetHighestQuality];
exporter.outputURL=url;
exporter.outputFileType = @"com.apple.quicktime-movie";
[exporter exportAsynchronouslyWithCompletionHandler:^{
[self savefinalVideoFileToDocuments:exporter.outputURL];
}];
-(void)savefinalVideoFileToDocuments:(NSURL *)url {
NSString *storePath = [[self applicationCacheDirectory] stringByAppendingPathComponent:@"Videos"];
NSData * movieData = [NSData dataWithContentsOfURL:url];
[movieData writeToFile:storePath atomically:YES];
}
- (NSString *)applicationCacheDirectory {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = ([paths count] > 0) ? [paths objectAtIndex:0] : nil;
return documentsDirectory;
}
迅速
var initPath1 = VideoLocalPath
var composition = AVMutableComposition.composition()
var inputVideoPath = initPath1
var sourceAsset = AVURLAsset(URL: URL(fileURLWithPath: inputVideoPath), options: nil)
var compositionVideoTrack = composition.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: kCMPersistentTrackID_Invalid)
var ok = false
var sourceVideoTrack = sourceAsset.tracks(withMediaType: AVMediaTypeVideo)[0]
var x = CMTimeRangeMake(kCMTimeZero, sourceAsset.duration)
do {
ok = try compositionVideoTrack.insertTimeRange(x, of: sourceVideoTrack, atTime: kCMTimeZero)
}
catch let error {
}
if FileManager.default.fileExists(atPath: initPath1) {
do {
try FileManager.default.removeItem(at: initPath1)
}
catch let error {
}
}
var url = URL(fileURLWithPath: initPath1)
var exporter = AVAssetExportSession(asset: composition, presetName: AVAssetExportPresetHighestQuality)
exporter.outputURL = url
func savefinalVideoFile(toDocuments url: URL) {
var storePath = NSURL(fileURLWithPath: self.applicationCacheDirectory()).appendingPathComponent("Videos")!.absoluteString
var movieData = Data(contentsOf: url)
movieData.write(toFile: storePath, atomically: true)
}
func applicationCacheDirectory() -> String {
var paths = NSSearchPathForDirectoriesInDomains(.cachesDirectory, .userDomainMask, true)
var documentsDirectory = (paths.count > 0) ? paths[0] : nil
return documentsDirectory
}
【讨论】：
这是我在项目中使用的，它适用于纵向视频，也可以调整为横向视频。
func removeSound(withFileURLs videoFileURL: URL, completion: @escaping (_ mergedVideoURL: URL?, _ error: Error?) -> Void) {
let composition = AVMutableComposition()
guard let videoTrack: AVMutableCompositionTrack = composition.addMutableTrack(withMediaType: .video, preferredTrackID: kCMPersistentTrackID_Invalid) else {
completion(nil, videoTrackError())
return
}
var instructions = [AVVideoCompositionInstructionProtocol]()
var isError = false
var currentTime: CMTime = CMTime.zero
var videoSize = CGSize.zero
var highestFrameRate = 0
let options = [AVURLAssetPreferPreciseDurationAndTimingKey: true]
let asset = AVURLAsset(url: videoFileURL, options: options)
guard let videoAsset: AVAssetTrack = asset.tracks(withMediaType: .video).first else {
return
}
if videoSize.equalTo(CGSize.zero) {
videoSize = (videoAsset.naturalSize)
}
var isVideoAssetPortrait_ = false
let videoTransform: CGAffineTransform = videoAsset.preferredTransform
if videoTransform.a == 0 && videoTransform.b == 1.0 && videoTransform.c == -1.0 && videoTransform.d == 0 {
isVideoAssetPortrait_ = true
}
if videoTransform.a == 0 && videoTransform.b == -1.0 && videoTransform.c == 1.0 && videoTransform.d == 0 {
isVideoAssetPortrait_ = true
}
var videoAssetWidth: CGFloat = videoAsset.naturalSize.width
var videoAssetHeight: CGFloat = videoAsset.naturalSize.height
if isVideoAssetPortrait_ {
videoAssetWidth = videoAsset.naturalSize.height
videoAssetHeight = videoAsset.naturalSize.width
}
videoSize.height = (videoAssetHeight)
videoSize.width = (videoAssetWidth)
let currentFrameRate = Int(roundf((videoAsset.nominalFrameRate)))
highestFrameRate = (currentFrameRate > highestFrameRate) ? currentFrameRate : highestFrameRate
let timeRange: CMTimeRange = CMTimeRangeMake(start: CMTime.zero, duration: asset.duration)
do {
try videoTrack.insertTimeRange(timeRange, of: videoAsset, at: currentTime)
let videoCompositionInstruction = AVMutableVideoCompositionInstruction.init()
videoCompositionInstruction.timeRange = CMTimeRangeMake(start: currentTime, duration: timeRange.duration)
let layerInstruction = AVMutableVideoCompositionLayerInstruction(assetTrack: videoTrack)
var isVideoAssetPortrait_ = false
let videoTransform: CGAffineTransform = videoAsset.preferredTransform
var videoAssetOrientation_: UIImage.Orientation = .up
if videoTransform.a == 0 && videoTransform.b == 1.0 && videoTransform.c == -1.0 && videoTransform.d == 0 {
videoAssetOrientation_ = .right
isVideoAssetPortrait_ = true
}
if videoTransform.a == 0 && videoTransform.b == -1.0 && videoTransform.c == 1.0 && videoTransform.d == 0 {
videoAssetOrientation_ = .left
isVideoAssetPortrait_ = true
}
if videoTransform.a == 1.0 && videoTransform.b == 0 && videoTransform.c == 0 && videoTransform.d == 1.0 {
videoAssetOrientation_ = .up
}
if videoTransform.a == -1.0 && videoTransform.b == 0 && videoTransform.c == 0 && videoTransform.d == -1.0 {
videoAssetOrientation_ = .down
}
var videoAssetWidth: CGFloat = videoAsset.naturalSize.width
var videoAssetHeight: CGFloat = videoAsset.naturalSize.height
if isVideoAssetPortrait_ {
videoAssetWidth = videoAsset.naturalSize.height
videoAssetHeight = videoAsset.naturalSize.width
}
var tx: Int = 0
if videoSize.width - videoAssetWidth != 0 {
tx = Int((videoSize.width - videoAssetWidth) / 2)
}
var ty: Int = 0
if videoSize.height - videoAssetHeight != 0 {
ty = Int((videoSize.height - videoAssetHeight) / 2)
}
var Scale = CGAffineTransform(scaleX: 1, y: 1)
var factor : CGFloat = 1.0
if tx != 0 && ty != 0 {
if tx <= ty {
factor = CGFloat(videoSize.width / videoAssetWidth)
Scale = CGAffineTransform(scaleX: CGFloat(factor), y: CGFloat(factor))
tx = 0
ty = Int((videoSize.height - videoAssetHeight * CGFloat(factor)) / 2)
}
if tx > ty {
factor = CGFloat(videoSize.height / videoAssetHeight)
Scale = CGAffineTransform(scaleX: CGFloat(factor), y: CGFloat(factor))
ty = 0
tx = Int((videoSize.width - videoAssetWidth * CGFloat(factor)) / 2)
}
}
var Move: CGAffineTransform!
var transform: CGAffineTransform!
switch videoAssetOrientation_ {
case UIImage.Orientation.right:
Move = CGAffineTransform(translationX: (videoAssetWidth * factor) + CGFloat(tx) , y: CGFloat(ty))
transform = CGAffineTransform(rotationAngle:degreeToRadian(90))
layerInstruction.setTransform(transform.concatenating(Scale.concatenating(Move)), at: .zero)
case UIImage.Orientation.left:
Move = CGAffineTransform(translationX: CGFloat(tx), y: videoSize.height - CGFloat(ty))
transform = CGAffineTransform(rotationAngle: degreeToRadian(270))
layerInstruction.setTransform(transform.concatenating(Scale.concatenating(Move)), at: .zero)
case UIImage.Orientation.up:
Move = CGAffineTransform(translationX: CGFloat(tx), y: CGFloat(ty))
layerInstruction.setTransform(Scale.concatenating(Move), at: .zero)
case UIImage.Orientation.down:
Move = CGAffineTransform(translationX: videoSize.width + CGFloat(tx), y: (videoAssetHeight*factor)+CGFloat(ty))
transform = CGAffineTransform(rotationAngle: degreeToRadian(180))
layerInstruction.setTransform(transform.concatenating(Scale.concatenating(Move)), at: .zero)
default:
break
}
videoCompositionInstruction.layerInstructions = [layerInstruction]
instructions.append(videoCompositionInstruction)
currentTime = CMTimeAdd(currentTime, timeRange.duration)
} catch {
print("Unable to load data: \(error)")
isError = true
completion(nil, error)
}
if isError == false {
let exportSession = AVAssetExportSession(asset: composition, presetName: AVAssetExportPresetHighestQuality)
let strFilePath: String = generateMergedVideoFilePath()
try? FileManager.default.removeItem(atPath: strFilePath)
exportSession?.outputURL = URL(fileURLWithPath: strFilePath)
exportSession?.outputFileType = .mp4
exportSession?.shouldOptimizeForNetworkUse = true
let mutableVideoComposition = AVMutableVideoComposition.init()
mutableVideoComposition.instructions = instructions
mutableVideoComposition.frameDuration = CMTimeMake(value: 1, timescale: Int32(highestFrameRate))
mutableVideoComposition.renderSize = videoSize
exportSession?.videoComposition = mutableVideoComposition
let exportCompletion: (() -> Void) = {() -> Void in
DispatchQueue.main.async(execute: {() -> Void in
completion(exportSession?.outputURL, exportSession?.error)
})
}
if let exportSession = exportSession {
exportSession.exportAsynchronously(completionHandler: {() -> Void in
switch exportSession.status {
case .completed:
print("Successfully merged")
exportCompletion()
case .failed:
print("Failed")
exportCompletion()
case .cancelled:
print("Cancelled")
exportCompletion()
case .unknown:
print("Unknown")
case .exporting:
print("Exporting")
case .waiting:
print("Wating")
}
})
}
}
}
func videoTrackError() -> Error {
let userInfo: [AnyHashable : Any] =
[ NSLocalizedDescriptionKey : NSLocalizedString("error", value: "Provide correct video file", comment: "") ,
NSLocalizedFailureReasonErrorKey : NSLocalizedString("error", value: "No video track available", comment: "")]
return NSError(domain: "VideoMerger", code: 404, userInfo: (userInfo as! [String : Any]))
}
func generateMergedVideoFilePath() -> String {
return URL(fileURLWithPath: ((FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last)?.path)!).appendingPathComponent("\(UUID().uuidString)-soundlessVideo.mp4").path
}
func degreeToRadian(_ degree: CGFloat) -> CGFloat {
return (.pi * degree / 180.0)
}
【讨论】：
在 Swift 3 中，
func removeAudioFromVideo(_ videoPath: String) {
let initPath1: String = videoPath
let composition = AVMutableComposition()
let inputVideoPath: String = initPath1
let sourceAsset = AVURLAsset(url: URL(fileURLWithPath: inputVideoPath), options: nil)
let compositionVideoTrack: AVMutableCompositionTrack? = composition.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: kCMPersistentTrackID_Invalid)
let sourceVideoTrack: AVAssetTrack? = sourceAsset.tracks(withMediaType: AVMediaTypeVideo)[0]
let x: CMTimeRange = CMTimeRangeMake(kCMTimeZero, sourceAsset.duration)
_ = try? compositionVideoTrack!.insertTimeRange(x, of: sourceVideoTrack!, at: kCMTimeZero)
if FileManager.default.fileExists(atPath: initPath1) {
try? FileManager.default.removeItem(atPath: initPath1)
}
let url = URL(fileURLWithPath: initPath1)
let exporter = AVAssetExportSession(asset: composition, presetName: AVAssetExportPresetHighestQuality)
exporter?.outputURL = url
exporter?.outputFileType = "com.apple.quicktime-movie"
exporter?.exportAsynchronously(completionHandler: {() -> Void in
self.saveFinalVideoFile(toDocuments: exporter!.outputURL!)
})
}
func saveFinalVideoFile(toDocuments url: URL) {
let fileURL = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false).appendingPathComponent("Videos")
let movieData = try? Data(contentsOf: url)
try? movieData?.write(to: fileURL, options: .atomic)
}
【讨论】：