After a lot of searching in the web I am going to ask here my question:
I want to stream audio between iPods WITHOUT or with less buffering. I am thinking of something like RTP or WebRTC for iOS.
The app which I will develop, enables one iPod to capture the microphone and to stream the audio to the other 50-100 iPods (Broadcast), but all this has to be LIVE.
One speaker's talk is recorded live and the other iPod's can hear the speaker at the same time with very less delay...
Is such a thing possible? Are there frameworks or software existing to handle this? I prefer Objective-C and HTML5.
I would be really happy getting any help. Thanks in forward.
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I'm having some trouble working with the iOS Audio frameworks to create a simple app. I would like to record audio through the Microphone and play it back to the user while recording.
I have tried each of the audio framework layers(AVFoundation, Audio Queue API, and RemoteIO), but have only found old documentation and broken examples.It seems like a simple request that AVFoundation should handle, but I have explored the following other SO questions and still find myself circling for hours to get the hang of this. Here is what I have reviewed:
iOS: Sample code for simultaneous record and playback (Other SO Users also state the accepted answer is not concrete and difficult to implement even with a delay of ~70ms.)
Record and play audio Simultaneously (From 2010 and very high level, I have downloaded the sample code and can't find a working example that does simultaneous playback and recording).
Adjust the length of an AudioUnit Buffer (RemoteIO is so confusing to me right now, is this really required?)
I have also downloaded and reviewed both the SpeakHere and AurioTouch sample projects from Apple. I promise I wouldn't post up without hours of googling and struggling. You can see "record audio and playback iOS simultaneously" returns many dated and non-working examples.I know myself and the community could really benefit from some updated documentation and examples in the audio section. RemoteIO seems to be too advanced for such a simple task. Thanks again for your help and consideration.
The appropriate way to do this is via AudioUnit APIs, even though it seems like a common scenario which should be handled by higher level APIs.
I wrote a small demo app using AudioUnit. You're free to try it our and modify it for suiting your purpose. The demo app does record audio and play it simultaneously, but it's recommended to use a ear phone to see the effect.
The RemoteIO Audio Unit is the only way to play back what is being recorded with low latency. RemoteIO is low latency because it runs audio callbacks in a separate dedicated real-time thread which is why it is fast, but also why it is a bit more complex to code. All the other iOS audio APIs are built on top of RemoteIO and thus add latency.
You will also need to configure the app's Audio Session APIs to request low latency with the appropriate audio session type. The foreground app can request and get audio input and output latencies as low as 5.6 milliseconds on most iOS devices most of the time.
I'm essentially working as a junior software engineer and I've been tasked with creating an iPad application that is capable of receiving a real-time stream from a UAV. The camera hardware hasn't been determined so I need to put a spec together so that it can be used in my iOS app.
However I feel like I'm massively inexperienced to do so as I don't have much of an understanding about media streaming and experience writing iOS apps to produce a decoder to play the video data - I started with Obj-C about 4 months ago when I joined the company.
I apologise if this isn't the best outlet for such a request but could anyone shed some light on the process of receiving low latency video streams or is it far beyond my current ability?
Thanks for any advice!
If you need to play the video you are receiving or do any playback operations, this should be what you are looking for: Writing an app to stream video to iPhone
You can also record the video, documentation from apple
I'm building an app in which I need to steam multiple tracks of audio that make up a song. They all need to be synchronized so the song plays back naturally.
I've been able to play back local multitrack audio very well with the solution on this thread: multi track mp3 playback for iOS application, but it looks like AVAudioPlayer isn't able to stream.
I've been looking into working with DOUAudioStreamer because I've read that it's the best solution for streaming audio on iOS without going pretty low-level, but it seems to lack the equivalent of a -playAtTime: method, which is how the tracks were synced up using `AVAudioPlayer.
Does anyone know a workaround for this using DOUAudioStreamer, or have any advice on another way I should approach this? Thanks.
I'd like to stream video from the camera on an iOS device to a receiver via wifi, in effect turning the device into a wireless webcam. Is there a way to build a small app that captures video input on an iOS app and sends it via an RTSP stream or similar?
As this is an ad hoc experiment, I'm not concerned about App Store guidelines and can jailbreak if necessary.
If I interpret your question correctly you more or less need to solve four problems:
Get the camera feed.
Convert/encode this to the right format.
Stream the data.
Prevent the phone from locking itself and going into deep sleep.
The first one is fairly simple and Apple has as always provided good documentation and examples -> API link. Make sure you check out their example in the end as you will get a CMSampleBufferRef data object back.
For the second and third part, you should check out the CFNetwork framework and specially CFFTPStream for streaming using FTP.
If your are only building this for yourself then you can always turn off the Auto-Lock feature in the settings. If you on the other hand would like to distribute this to other users you could use a trick to play a mute sound every 10 seconds. This is more or less how all the alarm clocks work in the App Store. Here's a tutorial. =)
I hope I helped a little bit at least.
Good luck and best regards!
I'm 70% of the way to doing the same thing. Here's how I did it:
Capture content from video input
Chop video into files for use in HTML Live Streaming.
Spin up a web server on the iPhone and make the video files available.
Connect to the IP address of the phone and viola! you've got live streaming video.
Last time I touched the code I was trying to debug my Live Streaming not working. I'll try and get my source code posted on github this weekend, if you'd like to take a look.
In my app I use MPMoviePlayerController to play an mp3 file from a web server. This plays while downloading the whole file, which is fine over WiFi. But now I want it to work over 3G (and get it into the app store). How do I get it to just buffer the next 10 seconds or so (as per apple rules)? I'm digging through the documentation on AVPlayer, HTTP Live streaming, etc, but I'm still confused about the best way to do this. With so many podcast apps out there, I'm suprised there aren't more tutorials/libraries about it.
Thanks for your time.
I investigated this as well, and I was not able find a way to limit the look-ahead buffer using MPMoviePlayerController. I believe you would have to load chunks at the network layer and feed them in at the AVFoundation layer, but I have not attempted this myself.
That said, I can confirm that you can get an app approved that plays mp3 files using MPMoviePlayerController over both WiFi and 3G connections. In my app I added a setting so the user can decide whether to enable mp3 downloads over 3G or not, although I don't know if that was needed to get approved. I provided it so users didn't inadvertently incur bandwidth costs.