ios - 录制视频时的音频音量

所以经过大量搜索后，我找到了允许在录制视频的同时播放背景音频的代码块。 我在下面粘贴了上述代码块。

fileprivate func setBackgroundAudioPreference() {
    guard allowBackgroundAudio == true else {
        return
    }

    guard audioEnabled == true else {
        return
    }

    do{
        if #available(iOS 10.0, *) {
            try AVAudioSession.sharedInstance().setCategory(.playAndRecord, mode: .default, options: [.mixWithOthers, .allowBluetooth, .allowAirPlay, .allowBluetoothA2DP])
        } else {
            let options: [AVAudioSession.CategoryOptions] = [.mixWithOthers, .allowBluetooth]
            let category = AVAudioSession.Category.playAndRecord
            let selector = NSSelectorFromString("setCategory:withOptions:error:")
            AVAudioSession.sharedInstance().perform(selector, with: category, with: options)
        }
        try AVAudioSession.sharedInstance().setActive(true)
        session.automaticallyConfiguresApplicationAudioSession = false
    }
    catch {
        print("[SwiftyCam]: Failed to set background audio preference")

    }
}

但是，我有一个小问题。由于某种原因，当相机加载背景时，音频音量会降低。当我用 instagram 录制视频时，音频不会减少，它仍然会录制有没有什么办法可以改变我当前的代码块，在用视频重新编码时不降低音量？

我阅读了文档，显然 .duckOthers 选项应该是减少音量的唯一选项。但是这个也可以

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Best Answer-推荐答案

好的，我在深入研究一些文档后找到了答案。

下面发布的更新代码。您所要做的就是设置 .defaultToSpeaker 选项

fileprivate func setBackgroundAudioPreference() {
    guard allowBackgroundAudio == true else {
        return
    }

    guard audioEnabled == true else {
        return
    }

    do{
        if #available(iOS 10.0, *) {
            try AVAudioSession.sharedInstance().setCategory(.playAndRecord, mode: .default, options: [.mixWithOthers, .allowBluetooth, .allowAirPlay, .allowBluetoothA2DP,.defaultToSpeaker])
        } else {
            let options: [AVAudioSession.CategoryOptions] = [.mixWithOthers, .allowBluetooth]
            let category = AVAudioSession.Category.playAndRecord
            let selector = NSSelectorFromString("setCategory:withOptions:error:")
            AVAudioSession.sharedInstance().perform(selector, with: category, with: options)
        }
        try AVAudioSession.sharedInstance().setActive(true)
        session.automaticallyConfiguresApplicationAudioSession = false
    }
    catch {
        print("[SwiftyCam]: Failed to set background audio preference")

    }
}

关于ios - 录制视频时的音频音量，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/54578598/