Comments (29)
There is a difference between the PTS (Presentation Time Stamp) calculated theoretically and the PTS received in practice. I believe this difference is manifesting as silence.
from haishinkit.swift.
Maybe this fix could have improved it. If you don't mind, I would like to ask you to test it. #1310
from haishinkit.swift.
I confirmed that the issue can be reproduced when launching Example.app while having a Discord call.
As indicated by 'Offset 128,' I confirmed that there is a corresponding gap in that area. It seems like using this value should work well.
CMBlockBuffer 0x282eea880 totalDataLength: 7680 retainCount: 1 allocator: 0x1e753bb30 subBlockCapacity: 2
[0] 7680 bytes @ offset 128 Buffer Reference:
CMBlockBuffer 0x282eea910 totalDataLength: 7832 retainCount: 1 allocator: 0x1e753bb30 subBlockCapacity: 2
[0] 7832 bytes @ offset 0 Memory Block 0x116782240, 7832 bytes (allocator 0x2827f2700)
}
from haishinkit.swift.
The fix made in #1208 was for the case of 2-channel stereo. It might not work correctly for 3 channels or more. It seems like the iPhone 14 Pro is detecting 4 channels.
from haishinkit.swift.
Thanks for your reply @shogo4405 😊
I tried to force the AVAudioSession preferredIntputChannels to 1 or 2 using the setPreferredIntputChannels.
While it seems to work on my iPhone 13mini, it seems it doesn't work on iPhone 14.
So if I have to deal with 4-channels samples. what would be the best way to deal with it inside Haishinkit from your point of view ?
Would I need to "remove" 2 channels from the CMSAmpleBuffer and then give it to the actual Haishinkit code to make it work or have you another idea about something that would make it work ? 🤔
from haishinkit.swift.
I have no idea. We have recently added support for multi-channels in #1273 and #1280. I have also tested it and it seems to work fine with 4 channels.
from haishinkit.swift.
You can try to discard channels within HK by providing a channel map. Negative value is used to discard an input channel:
myStream.audioSettings.outputChannelsMap = [0: 0, 1: 1, 2: -1, 3: -1]
from haishinkit.swift.
Also the format descriptions that show on the screenshots look like "input" audio format. HK does conversion from PCM to compressed AAC format. The "output" format can be found in AudioCodecSettings
. There's hardcoded maximum number of output channels which is 2. Any extra channels are removed, say you convert from 4 to 2 channels, channels 3 and 4 will be removed.
from haishinkit.swift.
I've made significant changes to the internal audio processing in #1294. There's a possibility that it brings improvements. You can test it on the 'main' branch.
from haishinkit.swift.
I'm currently testing it and will tell you if there is improvements or not.
If this does not improve things, I'll take a look and try some things about what @leo150 said earlier to see if it helps.
Thanks for your replies
from haishinkit.swift.
Hi,
I took some time to make several tests and waited for the iPhone 15 Pro release to confirm what I thought.
My issue is also happening on the iPhone 15 Pro.
As @leo150 mentioned, I tried to set audioSettings as below:
stream.audioSettings.bitRate = <info given by my backend>
stream.audioSettings.channels = 1
stream.audioSettings.channelMap = [0: 0, 1: 0, 2: -1, 3: -1]
But it seems it doesn't have any effect on the audio.
I also tried to update the library to use the latest code but it also doesn't seem to change anything.
One piece of info I may provide you is that my AVAudioSession is using playAndRecord
category & videoChat
mode because I have possible audio feedback on speaker and I want echo canceling/voice processing.
If I'm using AirPods or so, I use default
mode and it works as expected, but as soon as my AVAudioSession change, sound is behaving in this weird way.
I also tried, when AVAudioSession change, to detach audio from rtmpStream and then reattach it, thinking that maybe it'd get new settings from incoming audio and set things up in a different way that'd be able to handle audio. But it doesn't work either.
Are all of these info giving you any piece of idea or advice for me ?
from haishinkit.swift.
@shogo4405 @leo150 @CedricEugeni unfortunately we're facing the very same issue. What we've found is that the crackling sound is due to recurring silences or missing samples in the audio. Here are Audacity screenshots :
Here you can see the recurring silences or missing samples.
What we've found is that there's exactly 1024 samples between each recurring silences or missing samples. Therefore we concluded they are either at the beginning or at the end of each audio frame.
We've tried to dig into the resampler and ring buffer but we couldn't find anything that would help us determine where this could come from.
Do the screenshots and/or explanation make you think of anything ? Any help would be greatly appreciated 👍
Cheers
Quentin
from haishinkit.swift.
- Fork this code and provide logs of the print results showing the occurring symptoms. A log of about 30 seconds should be sufficient.
- If possible, please provide a simple code snippet for reproduction along with server access details. You can share the reproduction code via a pull request, and the server credentials can be sent via email.
from haishinkit.swift.
- We've managed to pin point what is causing the issue : when dealing with WebRTC and 4 channels,
CMSampleBuffer
s sent by theAVCaptureSession
sometimes start with 256 "padding/dummy" samples equal to 0 (it happens when the buffer number of samples > 960, there's no problem when the number of samples is exactly 960), the rest of the buffer being fine (here is an example). It leads to 64 silence samples being added per channel, which is exactly the length of silence observed in Audacity.
Unfortunately there doesn't seem to be any information in the CMSampleBuffer
informing its user that there's padding to be skipped at the start of the buffer 😱
Do you have any thought on that? Or any idea on how we could go about fixing this issue?
- It's not easy to provide reproducible steps, but we'll try it when we exhaust all other possibilities 👍
from haishinkit.swift.
Fork this code and provide logs of the print results showing the occurring symptoms. A log of about 30 seconds should be sufficient.
Code is here.
https://github.com/shogo4405/HaishinKit.swift/tree/feature/print-samplebuffer
I'm not interested in the byte sequence of the CMSampleBuffer. I want to know the PTS (Presentation Time Stamp). Please provide the dump result.
from haishinkit.swift.
Fork this code and provide logs of the print results showing the occurring symptoms. A log of about 30 seconds should be sufficient.
Code is here. https://github.com/shogo4405/HaishinKit.swift/tree/feature/print-samplebuffer
I'm not interested in the byte sequence of the CMSampleBuffer. I want to know the PTS (Presentation Time Stamp). Please provide the dump result.
Here's our dump. I had to add a ".zip" extension so that Github let me upload it.
Is it what you were looking for?
from haishinkit.swift.
Thanks for clearing that out 👍
Is there anything this lib or we could do to fix the issue? 🤔
from haishinkit.swift.
First off, thanks for providing a fix to test ❤️
Here's how it went: we had 2 problems
- a crackling sound
- audio was getting late compared to video which resulted in linear desynchronization between audio and video
Your patch fixed the second problem but not the first one.
Therefore I think it would be a good idea to merge it, but we still have an issue with the crackling sound.
from haishinkit.swift.
That looks pretty good indeed! Let us know whether you need any help testing a fix 👍
from haishinkit.swift.
It's being discussed on the developer forum.
https://developer.apple.com/forums/thread/715177
It seems like there is blank data at the beginning like this, which can disrupt calculations such as PTS (Presentation Time Stamp). When I remove the blank data, it sounds correct.
▫️▫️▫️▫️▪️▪️▪️▪️▪️
▫️▫️▫️▫️▪️▪️▪️▪️▪️
▪️▪️▪️▪️▪️▪️▪️▪️▪️
▫️▫️▫️▫️▪️▪️▪️▪️▪️
▫️▫️▫️▫️▪️▪️▪️▪️▪️
▪️▪️▪️▪️▪️▪️▪️▪️▪️
▫️▫️▫️▫️▪️▪️▪️▪️▪️
▫️▫️▫️▫️▪️▪️▪️▪️▪️
▪️▪️▪️▪️▪️▪️▪️▪️▪️
from haishinkit.swift.
Did you manage to find a way to automatically remove that annoying blank data based on the CMBlockBuffer information (like the offset
you mentioned earlier) or are you missing information?
from haishinkit.swift.
I haven't found a way to retrieve it from the parameters.
from haishinkit.swift.
@shogo4405 what are you looking to do regarding this issue? We're still experiencing crackling noise.
Cheers
from haishinkit.swift.
Are you saying that it's still occurring in the post-fix branch at https://github.com/shogo4405/HaishinKit.swift/pull/1310/files? If so, I won't be able to fix it because I can't reproduce it in my environment.
from haishinkit.swift.
With your post-fix branch, we're experiencing:
- way less crackling noise but still random ones every 1 or 2 seconds. they are far more difficult to hear but they are there
- if we record for a few minutes, we see that audio/video get unsynchronized (video is late compared to audio)
Random crackling noises may be due to audio/video getting unsynchronized 🤔
from haishinkit.swift.
The direction of the modifications seems promising. I believe that with extensive debugging, improvements can be achieved. On the other hand, I'm currently allocating my time for the 1.7.0 release, so the subsequent fixes will have to wait.
from haishinkit.swift.
OK thanks for the clarifications 👍 we're available if you need help to debug or test improvements whenever you go back to that issue. Thanks again ❤️
from haishinkit.swift.
As a temporary solution, I disabled voice processing in voice_processing_audio_unit.mm:76 and the issue is gone. In our case the voice processing isn't a requirement.
vpio_unit_description.componentSubType = kAudioUnitSubType_RemoteIO;
I don't have time to create a reproducible example, but ideally we need to add a voice processing unit to the HaishinKit example app so the issue could looked into.
from haishinkit.swift.
You can reproduce the issue by starting the HaishinKit sample app while on a call in Discord. Since I don't have a good improvement plan at the moment, I will move this to the Discussion section for now.
from haishinkit.swift.
Related Issues (20)
- What happens when playing pure audio fails? We only did audio push-pull streaming, but we ran into problems playing it back. HOT 6
- When I closed the stream and then turned it back on, the log showed that it was connected, but frequent switching results in low transmission speed HOT 2
- Recording is broken if using an audio sample rate is set to 44.1 kHz HOT 1
- App audio performance issue HOT 3
- videoCodecErrorOccurred reason=failedToFlame(status: 0), description=The operation couldn’t be completed. (HaishinKit.IOVideoUnitError error 3.) HOT 2
- Metadata issue leading to out-of-sync audio after recording on server HOT 16
- RTMP: First AVC interframe has timestamp delta == 0
- CPU usage increases after SRT Playback ends HOT 1
- ReplayKit and multicam .audioMic issue HOT 6
- Exception "required condition is false: [_nodes containsObject: node]" when I close RTMP stream connection HOT 6
- LTE and 5G Network Connection Failure: POSIXErrorCode(rawValue: 50): Network is down HOT 4
- Change resolution during stream HOT 4
- Recording not working since 1.8.0 HOT 3
- connection closed by peer on stopping the RTMP stream HOT 6
- [Sponsorship] Need Help with New Features HOT 1
- [SRT] After `SRTConnection.close` `SRTConnection.connected` is true
- [SRT] After fist live audio does not have a program
- Black screen at the trailing HOT 1
- NetConnection.Connect.Failed when I use RTMP stream with H264
- [Bug Maybe] Feedback for 1.8.0 and 1.8.2 HOT 3
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.
from haishinkit.swift.