ios – 使用AudioKit裁剪MIDI文件_app

let loopStart = 12.0let loopLength = 4.0// keep track of the original track contentslet originalLength = 16.0let originalContents = track.getMIDINoteData()// isolate the segment for looPing and shift it to the start of the tracklet loopSegment = originalContents.filter { loopStart ..< (loopStart + loopLength) ~= [+++].position.beats }let shiftedSegment = loopSegment.map { AKMIDINoteData(noteNumber: [+++].noteNumber,veLocity: [+++].veLocity,channel: [+++].channel,duration: [+++].duration,position: AKDuration(beats: [+++].position.beats - loopStart))}// replace the track contents with the loop,and assert the looPing behavIoUrtrack.replaceMIDINoteData(with: shiftedSegment)seq.setLength(AKDuration(beats: loopLength))seq.enableLooPing()// and to get back to the original:track.replaceMIDINoteData(with: originalContents)seq.setLength(AKDuration(beats: originalLength))seq.enableLooPing()

let loopStart = 12.0let loopLength = 4.0// keep track of the original track contentslet originalLength = 16.0let originalContents = track.getMIDINoteData()// isolate the segment for looPing and shift it to the start of the tracklet loopSegment = originalContents.filter { loopStart ..< (loopStart + loopLength) ~= .position.beats }let shiftedSegment = loopSegment.map { AKMIDINoteData(noteNumber: [+++].noteNumber,veLocity: [+++].veLocity,channel: [+++].channel,duration: [+++].duration,position: AKDuration(beats: [+++].position.beats - loopStart))}// replace the track contents with the loop,and assert the looPing behavIoUrtrack.replaceMIDINoteData(with: shiftedSegment)seq.setLength(AKDuration(beats: loopLength))seq.enableLooPing()// and to get back to the original:track.replaceMIDINoteData(with: originalContents)seq.setLength(AKDuration(beats: originalLength))seq.enableLooPing()

let loopStart = 12.0let loopLength = 4.0// keep track of the original track contentslet originalLength = 16.0let originalContents = track.getMIDINoteData()// isolate the segment for looPing and shift it to the start of the tracklet loopSegment = originalContents.filter { loopStart ..< (loopStart + loopLength) ~= .position.beats }let shiftedSegment = loopSegment.map { AKMIDINoteData(noteNumber: .noteNumber,veLocity: [+++].veLocity,channel: [+++].channel,duration: [+++].duration,position: AKDuration(beats: [+++].position.beats - loopStart))}// replace the track contents with the loop,and assert the looPing behavIoUrtrack.replaceMIDINoteData(with: shiftedSegment)seq.setLength(AKDuration(beats: loopLength))seq.enableLooPing()// and to get back to the original:track.replaceMIDINoteData(with: originalContents)seq.setLength(AKDuration(beats: originalLength))seq.enableLooPing()

let loopStart = 12.0let loopLength = 4.0// keep track of the original track contentslet originalLength = 16.0let originalContents = track.getMIDINoteData()// isolate the segment for looPing and shift it to the start of the tracklet loopSegment = originalContents.filter { loopStart ..< (loopStart + loopLength) ~= .position.beats }let shiftedSegment = loopSegment.map { AKMIDINoteData(noteNumber: .noteNumber,veLocity: .veLocity,channel: [+++].channel,duration: [+++].duration,position: AKDuration(beats: [+++].position.beats - loopStart))}// replace the track contents with the loop,and assert the looPing behavIoUrtrack.replaceMIDINoteData(with: shiftedSegment)seq.setLength(AKDuration(beats: loopLength))seq.enableLooPing()// and to get back to the original:track.replaceMIDINoteData(with: originalContents)seq.setLength(AKDuration(beats: originalLength))seq.enableLooPing()

let loopStart = 12.0let loopLength = 4.0// keep track of the original track contentslet originalLength = 16.0let originalContents = track.getMIDINoteData()// isolate the segment for looPing and shift it to the start of the tracklet loopSegment = originalContents.filter { loopStart ..< (loopStart + loopLength) ~= .position.beats }let shiftedSegment = loopSegment.map { AKMIDINoteData(noteNumber: .noteNumber,veLocity: .veLocity,channel: .channel,duration: [+++].duration,position: AKDuration(beats: [+++].position.beats - loopStart))}// replace the track contents with the loop,and assert the looPing behavIoUrtrack.replaceMIDINoteData(with: shiftedSegment)seq.setLength(AKDuration(beats: loopLength))seq.enableLooPing()// and to get back to the original:track.replaceMIDINoteData(with: originalContents)seq.setLength(AKDuration(beats: originalLength))seq.enableLooPing()

let loopStart = 12.0let loopLength = 4.0// keep track of the original track contentslet originalLength = 16.0let originalContents = track.getMIDINoteData()// isolate the segment for looPing and shift it to the start of the tracklet loopSegment = originalContents.filter { loopStart ..< (loopStart + loopLength) ~= .position.beats }let shiftedSegment = loopSegment.map { AKMIDINoteData(noteNumber: .noteNumber,veLocity: .veLocity,channel: .channel,duration: .duration,position: AKDuration(beats: [+++].position.beats - loopStart))}// replace the track contents with the loop,and assert the looPing behavIoUrtrack.replaceMIDINoteData(with: shiftedSegment)seq.setLength(AKDuration(beats: loopLength))seq.enableLooPing()// and to get back to the original:track.replaceMIDINoteData(with: originalContents)seq.setLength(AKDuration(beats: originalLength))seq.enableLooPing()

概述我正在尝试使用AudioKit裁剪并循环MIDI文件的某个部分. 我正在使用一个音序器,发现了一些接近我需要的东西,但并不完全正确. 我在AKSequencer中找到了一个名为clearRange的方法.通过这种方法,我能够使我不想要的MIDI部分静音,但是我还没有找到一种方法来修剪音序器,只保留我感兴趣的部分.现在只有我想要的部分有声音但我仍然得到了沉默的部分. 有没有办法修剪一个音序器或创建一我正在尝试使用AudioKit裁剪并循环MIDI文件的某个部分.

我正在使用一个音序器,发现了一些接近我需要的东西,但并不完全正确.

我在AKSequencer中找到了一个名为clearRange的方法.通过这种方法,我能够使我不想要的MIDI部分静音,但是我还没有找到一种方法来修剪音序器,只保留我感兴趣的部分.现在只有我想要的部分有声音但我仍然得到了沉默的部分.

有没有办法修剪一个音序器或创建一个新的音序器,只有我想要保留原音序列？

谢谢！

解决方法 Apple的MusicSequence(AKSequencer所基于的)的一个令人沮丧的限制是,尽管您可以轻松设置循环部分的“右侧”,但左侧将始终循环回零并且无法更改.因此,要从左侧裁剪,您需要隔离要循环的部分并将其移位,以使循环的开始为零.

从AudioKit 4.2.4开始,这是可能的.使用AKMusicTrack的.getMIDINoteData()获取AKMIDINoteData结构数组,其内容可以编辑,然后用于替换原始数据.如果你有一个16节拍的曲目你想要循环最后四个节拍,你可以做一些事情：

let loopStart = 12.0let loopLength = 4.0// keep track of the original track contentslet originalLength = 16.0let originalContents = track.getMIDINoteData()// isolate the segment for looPing and shift it to the start of the tracklet loopSegment = originalContents.filter { loopStart ..< (loopStart + loopLength) ~= .position.beats }let shiftedSegment = loopSegment.map { AKMIDINoteData(noteNumber: .noteNumber,veLocity: .veLocity,channel: .channel,duration: .duration,position: AKDuration(beats: .position.beats - loopStart))}// replace the track contents with the loop,and assert the looPing behavIoUrtrack.replaceMIDINoteData(with: shiftedSegment)seq.setLength(AKDuration(beats: loopLength))seq.enableLooPing()// and to get back to the original:track.replaceMIDINoteData(with: originalContents)seq.setLength(AKDuration(beats: originalLength))seq.enableLooPing()

如果你想循环部分重复原始序列的长度,那么你可以使用shiftedSegment作为模板并从中构建一个16拍序列.

总结

以上是内存溢出为你收集整理的ios – 使用AudioKit裁剪MIDI文件全部内容，希望文章能够帮你解决ios – 使用AudioKit裁剪MIDI文件所遇到的程序开发问题。

如果觉得内存溢出网站内容还不错，欢迎将内存溢出网站推荐给程序员好友。

欢迎分享，转载请注明来源：内存溢出

原文地址: http://outofmemory.cn/web/1033205.html