Xcode 7 - 无法调用 AudioFileStreamOpen

Posted 2023-02-25

【中文标题】Xcode 7 - 无法调用 AudioFileStreamOpen

【英文标题】：Xcode 7 - Can't call AudioFileStreamOpen

【发布时间】：2015-07-02 18:44:14

【问题描述】：

我似乎无法解决这个问题。尝试使用音频文件流服务。

一些代码：

import Foundation
import AudioToolbox

public class StreamingPlayback 
    var audioFileStream: UnsafeMutablePointer<AudioFileStreamID>?
    var inClientData: UnsafeMutablePointer<Void> = nil

    init() 
    

    func start () 
        AudioFileStreamOpen(&inClientData, propertyProc, packetProc, kAudioFileMP3Type, &audioFileStream)
    

    func propertyProc(inClientData: UnsafeMutablePointer<()>,inFileStreamId: AudioFileStreamID,inPropertyId: AudioFileStreamPropertyID,ioFlags: UnsafeMutablePointer<UInt32>) -> Void 
    

    func packetProc(inClientData: UnsafeMutablePointer<()>,inNumberOfBytes: UInt32,inNumberOfPackets: UInt32, UnsafeMutablePointer<()>, inPacketDescriptions: UnsafePointer<AudiostreamPacketDescription>) -> Void 
    

这给了我：

Cannot invoke 'AudioFileStreamOpen' with an argument list of type '(inout UnsafeMutablePointer<Void>, (UnsafeMutablePointer<()>, inFileStreamId: AudioFileStreamID, inPropertyId: AudioFileStreamPropertyID, ioFlags: UnsafeMutablePointer<UInt32>) -> Void, (UnsafeMutablePointer<()>, inNumberOfBytes: UInt32, inNumberOfPackets: UInt32, UnsafeMutablePointer<()>, inPacketDescriptions: UnsafePointer<AudioStreamPacketDescription>) -> Void, AudioFileTypeID, inout UnsafeMutablePointer<AudioFileStreamID>?)'

Expected an argument list of type '(UnsafeMutablePointer<Void>, AudioFileStream_PropertyListenerProc, AudioFileStream_PacketsProc, AudioFileTypeID, UnsafeMutablePointer<AudioFileStreamID>)'

谁能告诉我我做错了什么？

【参考方案1】：

我刚刚遇到了这个问题。尽管 Swift 2.0 支持 c 函数回调，但仍然存在一些问题。我确实找到了解决方法。试试这个：

@objc protocol HandleAudioPacketsDelegate 
    func handlePacketsProc(ioActionFlags: UnsafeMutablePointer<AudioUnitRenderActionFlags>,
        inTimeStamp: UnsafePointer<AudioTimeStamp>,
        inBufNumber: UInt32,
        inNumberFrames: UInt32,
        ioData: UnsafeMutablePointer<AudioBufferList>) -> OSStatus


func packetsProc(inRefCon: UnsafeMutablePointer<Void>,
    ioActionFlags: UnsafeMutablePointer<AudioUnitRenderActionFlags>,
    inTimeStamp: UnsafePointer<AudioTimeStamp>,
    inBufNumber: UInt32,
    inNumberFrames: UInt32,
    ioData: UnsafeMutablePointer<AudioBufferList>)
    -> OSStatus

    let delegate = unsafeBitCast(inRefCon, HandleAudioPacketsDelegate.self)
    let result = delegate.handlePacketsProc(ioActionFlags,
        inTimeStamp: inTimeStamp,
        inBufNumber: inBufNumber,
        inNumberFrames: inNumberFrames,
        ioData: ioData)
    return result

然后在您的StreamingPlayback 类中使用此方法进行回调：

func handlePacketsProcioActionFlags: UnsafeMutablePointer<AudioUnitRenderActionFlags>,
    inTimeStamp: UnsafePointer<AudioTimeStamp>,
    inBufNumber: UInt32,
    inNumberFrames: UInt32,
    ioData: UnsafeMutablePointer<AudioBufferList>) -> OSStatus 

【讨论】：

我可以通过 skype/email/fb messenger 引导您完成此操作。如果您愿意，也很乐意谈论音频流/swift。这个组合有很多障碍，只有一个小社区知道如何与这两者合作。你的联系方式是什么？