我正在尝试使用 AVPlayer
淡入视频开头的音频轨道 . 播放视频时没有任何错误,似乎音量已经达到100%,并且我的 volumeRamp
音频淡入未执行 .
这是我的代码:
guard let url = (self.videoView.player?.currentItem?.asset as? AVURLAsset)?.url else { return }
let asset = AVAsset(url: url) as AVAsset
let duration = asset.duration
let durationInSeconds = CMTimeGetSeconds(duration)
let playerItem = AVPlayerItem(asset: asset)
let firstSecond = CMTimeRangeMake(CMTimeMakeWithSeconds(0, 1), CMTimeMakeWithSeconds(1, 1))
// Configure audio mix to fade in
let audioParams = AVMutableAudioMixInputParameters(track: asset.tracks.first!)
audioParams.setVolumeRamp(fromStartVolume: 0, toEndVolume: 1, timeRange: firstSecond)
let mix = AVMutableAudioMix()
mix.inputParameters = [audioParams]
playerItem.audioMix = mix
self.videoView.player?.replaceCurrentItem(with: playerItem)
self.videoView.player?.play()
难道我做错了什么 ? (我正在用模拟器测试)