如何将FFMPEG AV_CODEC_ID_PCM_S16BE音频数据提供给AudioQueue(How to feed FFMPEG AV_CODEC_ID_PCM_S16BE audio data to AudioQueue)

 我正在使用FFMPEG与FFmpegAudioPlayer结合进行直播。 我遇到的问题是，虽然音频可以被解码和播放，但是音频中存在持续的点击/尖叫噪声，当其他应用程序流式传输相同的源时，该噪声不存在。 所以我猜这个问题是由于我将FFMPEG AV_CODEC_ID_PCM_S16BE音频数据处理到AudioQueue之前的处理方式： 
 
audioFormat.mFormatID = kAudioFormatLinearPCM;            
audioFormat.mFormatFlags = kAudioFormatFlagsCanonical;//kAudioFormatFlagIsBigEndian|kAudioFormatFlagIsAlignedHigh;
audioFormat.mSampleRate = pAudioCodecCtx->sample_rate;
audioFormat.mBitsPerChannel = 8*av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
audioFormat.mChannelsPerFrame = pAudioCodecCtx->channels;
audioFormat.mBytesPerFrame = pAudioCodecCtx->channels * av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
audioFormat.mBytesPerPacket= pAudioCodecCtx->channels * av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
audioFormat.mFramesPerPacket = 1;
audioFormat.mReserved = 0;

pSwrCtx = swr_alloc_set_opts(pSwrCtx,
                                             1,//pAudioCodecCtx->channel_layout,
                                             AV_SAMPLE_FMT_S16,
                                             pAudioCodecCtx->sample_rate,
                                             1,//pAudioCodecCtx->channel_layout,
                                             AV_SAMPLE_FMT_S16,
                                             pAudioCodecCtx->sample_rate,
                                             0,
                                             0);
outCount = swr_convert(pSwrCtx,
                                             (uint8_t **)(&pOut),
                                             in_samples,
                                             (const uint8_t **)pAVFrame1->extended_data,
                                             in_samples);
 
 还请注意，我为swr_alloc_set_opts尝试了许多不同的参数，但音频变得无法识别或噪音持续存在。 
 
 这是一个带有咔嗒声的音频样本，如果有帮助的话。 

I am using FFMPEG in combination with FFmpegAudioPlayer to do live streaming. The issue I am having is that, while the audio can be decoded and played, there's a constant clicking/screeching noise in the audio that isn't present when streaming the same source by other applications. So I am guess the issue arise due to how I process the FFMPEG AV_CODEC_ID_PCM_S16BE audio data before handing it to AudioQueue:
 
audioFormat.mFormatID = kAudioFormatLinearPCM;            
audioFormat.mFormatFlags = kAudioFormatFlagsCanonical;//kAudioFormatFlagIsBigEndian|kAudioFormatFlagIsAlignedHigh;
audioFormat.mSampleRate = pAudioCodecCtx->sample_rate;
audioFormat.mBitsPerChannel = 8*av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
audioFormat.mChannelsPerFrame = pAudioCodecCtx->channels;
audioFormat.mBytesPerFrame = pAudioCodecCtx->channels * av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
audioFormat.mBytesPerPacket= pAudioCodecCtx->channels * av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
audioFormat.mFramesPerPacket = 1;
audioFormat.mReserved = 0;

pSwrCtx = swr_alloc_set_opts(pSwrCtx,
                                             1,//pAudioCodecCtx->channel_layout,
                                             AV_SAMPLE_FMT_S16,
                                             pAudioCodecCtx->sample_rate,
                                             1,//pAudioCodecCtx->channel_layout,
                                             AV_SAMPLE_FMT_S16,
                                             pAudioCodecCtx->sample_rate,
                                             0,
                                             0);
outCount = swr_convert(pSwrCtx,
                                             (uint8_t **)(&pOut),
                                             in_samples,
                                             (const uint8_t **)pAVFrame1->extended_data,
                                             in_samples);
 
Please also note that I've tried many different parameters for swr_alloc_set_opts, but either the audio became unrecognizable or the noise persisted.
 
Here's a sample of the audio with clicking sound, if it helps.

原文：https://stackoverflow.com/questions/26499668