Streaming audio to mobile phones, what technology to use? - iphone

I'm planning on building an application where audio media is going to be streamed to the mobile phone for the user to listen.
The targets are smartphones: iPhone/Blackberry/Android/(J2ME ?).
I see that streaming on iPhone has to be done with HTTP Live streaming, but I don't see it supported by other platforms.
Should I broadcast the streams via rstp ? http ? Is there any way to use a unified solution for all the different mobile platform ? If anyone already had to go through this, help would be greatly appreciated.

One answer to the question "what technology to use ?", for iPhone specifically is WiFi. I know that's not the type of question you are asking, but its a point worth making! Many apps that support streaming over 3G have been rejected by Apple due to bandwidth usage. You may need to be prepared to sense network connection type and limit streaming to when you have a WiFi connection only.

Blackberry works with http and RSTP on OS 4.3 or later. I'm not familiar with other platforms but I would think http would be the most compatible.
Here is a PDF that lists the supported types by the major models.
http://docs.blackberry.com/en/smartphone_users/deliverables/15801/711-01774-123_Supported_Media_Types_on_BlackBerry_Smartphones.pdf

You will probably want to do RTSP, but it doesn't really matter. HTTP Live Streaming is just a protocol on the client side I am pretty sure. All these acronyms just describe ways of transmitting data. If a browser can access the data for a given protocol....chances are a phone can too. It sounds like you are asking more of a server side question.....but that question is the least of your worries You are going to have to think more along the lines of "How am I going to scale this" rather than "What protocol should I use to transmit data". Also, the unified solution for all clients, would be to have a server that they all hit for data. You still need to develop separate clients for each OS.

Both Android and BlackBerry supports RTSP.
Note that some BlackBerry devices only support 15fps video, so you may need separated streams to give the best experience to your users.
iPhone, starting from iPhone OS 3.0, needs HTTP Live Streaming.
The only software solution I know to support all above is Wowza, but you still need an encoder. (I think Wowza supports RTP as input, but need double checking.)

iPhone can play non-streamed audio (progressive download). Considered all platforms you would normally you just needs streams that are suitable transcoded. See f.e. https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/StreamingMediaGuide/Introduction/Introduction.html The title says its about 'HTTP Live Streaming' but a lot applies for just downloading and playing streams.

Related

iPhone peer-to-peer voice chat

I see that Game Kit allows you to develop games with voice chat.
I want to build a more general, peer-to-peer voice chat application, that does not have to live in the Game Center. So a couple questions:
1. What peer to peer system/technologies could be used for this?
2. If I wanted to allow voice chat with a Flash client (i.e. iPhone app <--> Server <---> Flash client on PC) would options for 1 work for this?
I have some experience with RTFMP for Flash to Flash client chat, and no iPhone dev experience, so just want to test out some ideas.
Maybe one idea: build using the Ribbit Platform - they have both Objective-C and Flash SDKs, but this looks more like traditional\SIP calling.
Anyway, would appreciate anything that points me in the right direction.
Thanks.
Now that flash has access to raw Microphone data, you could roll your own client and server; yet, since, currently, it doesn't have UDP sockets in AIR for mobile, you would be forced into considering audio quality vs lagg with even tighter restrictions then usual.
You can now roll your own native extension to make this work; yet, I am assuming you want something that only requires coding in AS3.
Therefore, considering your restrictions, the only real bet would be to use Flash's built-in communications capabilities (e.g. RTMP).
With the above being said, there are opensource alternatives to the array of Adobe's own flash communication servers:
the red5 server, and rtmpd.
IMHO Ribbit's services are kind of pointless.

How to do peer-to-peer communication in an iPhone app?

I'm trying to write a simple chat application for the iPhone (as an experiment). Is there a simple way for two devices to discover each others' IP addresses, and given the addresses is there a simple API or protocol that would let me send text messages back and forth?
I've investigated SIP (specifically Sofia and eXosip), but these tools exist as C libraries and are beyond my current ability to port them to the iPhone.
Update: I'm trying to connect two devices over the Internet (i.e. not over Bluetooth or a local wireless network, which is what GameKit does).
You're going to need a server that provides the match making service. Game Center makes this pretty easy, but your users will have to have Game Center accounts.
Alternatively, you can set up an XMPP (formerly Jabber, it's what powers Google Chat) server (I've never done this, but there are several available) and use the XMPP Framework for Cocoa. There are instructions for using it in iPhone apps here.
I'm sure there are other chat servers and client source also available. IRC and Mobile Colloquy come to mind.
Finally, you could write your own server using your favorite server language / framework. This isn't too hard (I've done it myself), but it's far from what I'd call simple, and I wouldn't use it for a production system.
There is support for exactly this kind of ad-hoc peer-to-peer networking in GameKit. Have a look at the second half of the GameKit documentation for details:
http://developer.apple.com/library/ios/#documentation/...
NSNetService is a good option.
Take a look at WebRTC Datachannels. WebRTC is a newer option with native iOS support a standard that is still being finalized, but it is more flexible should the iOS app need to communicate with browser or even android peers

How can I send simple data from an iPhone to another iPhone, or an Android?

I'm just getting started with mobile development, and after considerable searching I'm still confused about sending a message from my iPhone to another or an Android. For instance, in building a simple Tic-Tac-Toe game, if I want to notify the other phone of a move, what is the best way to do so? Wifi, bluetooth, 3G? And how?
Many methods seem to point to communicating through a web server, but I'd rather send them directly from phone to phone if possible. (this is for native apps of course)
If you don't want to have a server (or even if you do! It depends!) it sounds like you will want to use TCP sockets. Apple doesn't have a generic bluetooth API to use with iPhone-to-android communication and you'll have TCP access anyway with 3G. A 3G network connection is very similar to wifi and you should be able to check for the difference as needed with little change to your overall networking code. I'm not sure if bonjour is supported on android, but I bet someone has ported it for similar reasons already, and it is supported in iOS. Apple has a networking section for iOS that you may find informative.
Additionally if you want to stay within the iOS device only realm you could use GameKit to communicate via bluetooth.
Hope that helps some.
The easiest way is to create a web server with an API and the clients poll the server for new moves (or the server pushes the client an update). This is the only way you're going to be able to do it over 3G unless you can figure out the IP addresses of both phones (do phones even keep the same IP address for a long period of time?) and open up sockets between them and let one phone be the server and the other be the client (could cause potential cheating).
WiFi is not always there - by limiting your users' options to areas with access points, you'll lose sales. Not sure about Bluetooth - how prevalent is it on handsets, how much of the API is exposed. Your best bet, IMHO, is 3G. With some kind of a central presence server (Web or otherwise), with optional proxying. Read up on peer-to-peer networking.
As far as i know does the iphone only support incoming messages over push notifications.
This means, that you have to update the information, by requesting it from web services etc.
The bluetooth API of the iphone doesn't support this either.

Sending data between OSX and iPhones/iPads

I am wondering how I can send data between a machine and a mobile device. I know about the game kit an have read a bit about bonjour (but don't know to much about it), but would like to know some expert thoughts on what the best way is.
What I basically want to build is a one way traffic application that sends data from OSX to the mobile device (iPhone, iPod touch or iPad). The data send is either pictures, text (of a certain size and position ect) or video. The mobile device just has to receive this data and display it... nothing more.
My guess is that a WiFi solution would be best.
How could I best do this? Are there any tutorials that might help me putting this together?
Thanks in advance!
Best regards,
Paul Peelen
As no reply yet . . .
Bonjour is more focused on LAN networks, so would restrict you to WiFi.
It's also more of a service discovery standard - your Mac app would advertise the service on the LAN, and clients could see it - but your actual app communications will run on a different TCP socket, using whatever protocol is appropriate.
This linked answer may be helpful (although you will want CFNetwork in reverse - pushing from Mac to phone)
[iPhone]: How send output stream via wireless network?
For video you are probably better off looking for higher level frameworks (i.e. the AV ones).
Without knowing the full details of what you want to do, I wonder if rather than pushing data to the iPhone, the best thing would be to send a lightweight notification to the iPhone (AMQP, XMPP, or similar protocol) passing a URL back to the resource on the Mac - that way you could use standard HTTP GET for images, video, etc, on the iPhone side, throw the URL at a webkit view to display - and on your Mac side you could then use an off-the-shelf web server (Apache, or an embedded HTTP server within your code).

Is it possible, in principle, for an Android device to interface with an iPhone over Bluetooth/GameKit?

(I am not interested in pure theory, but as a practical near or mid-term possibility, say within 12-24 months.)
As a developer familiar with (but not specializing in) two major smartphone platforms, should I expect an Android library to come out which can spoof itself onto an iPhone app's GameKit-based network. It seems reasonable that a Bluetooth interface between platforms might square the opportunity to make useful applications, in the same way that modems benefited PC/Mac platforms via Metcalfe's Law.
I am looking for one of two answers:
Is this obviously not likely (e.g. because of encryption)? If so, what is the reason? Is it possible in principle, but requiring years of reverse-engineering (like SMB/CIFS/Samba)? Or is it a no-brainer and just a matter of time? Please give evidence supporting your reason.
Is there an alternative way to have direct peer-to-peer networking besides GameKit? For example, a hand-rolled network using Bluetooth or ad-hoc WiFi? It would be nice to spoof an Android device into an existing iPhone app but my main question is, can the devices speak with each other at all!
Yes, it is possible. GameKit is a protocol using TCP and/or UDP over a BNEP Bluetooth connection. It also uses a trick to identify other iOS devices using the Extended Inquiry mechanism in Bluetooth 2.1+.
I was able to simulate the EIR responses, now, someone needs to reverse engineer the GameKit protocol. This doesn't need Bluetooth, as it is also used for GameKit connections over WLAN.
If anybody can re-implment GameKit for WLAN connections, I can finish the Bluetooth version.
No, and it wont come soon or even at all... Apple pride themselves with their security features, and bluetooth connections can access private data. There will probably not be any cross platform bluetooth framework until something is agreed upon by both companies.
Bump as said by a previous answerer uses a remote server, and the data transferred is not via BT.
GameKit is Bonjour so a Bonjour (which is on IP) over Bluetooth on Android should work.
That should be possible as Bluetooth is capable of setting up tcp/ip networks. Though I have no knowledge of the IPhone SDK whatsoever, but Android does have a BluetoothSocket and BluetoothServerSocket for TCP connections.
This article, http://blog.moritzhaarmann.de/blog/2014/04/27/sorry-state-of-p2p/ written in 2014, suggest it is possible via Bluetooth LE. Available in Android 4.3+ and iOS6+
Two issues:
According to the Android Dashboard only around 30 percent of Android devices support Bluetooth LE https://developer.android.com/about/dashboards/index.html?utm_source=ausdroid.net
Communication between Android-to-Android must be done using some other method (which is not a big problem) because Android devices cannot act as server for B LE connections.
Bounjour on the iPhone gives you full access to all of the Bluetooth protocols, so you don't have to use GameKit. As for when someone will provide an easy to use iPhone to Android GameKit like framework - hard to tell.
An iPhone can already talk to any other Bluetooth device using Bonjour today.
-t
It is absolutely possible! In fact I am amazed that more people haven't done it!
Theory:
Bluetooth is just a wireless socket that you push data across and it comes across the other side, just like tcp/ip.
Practice:
http://www.techcrunch.com/2009/11/11/bump-goes-cross-platform-with-new-android-app-upgrades-iphone-version-too/
Better yet, Bump is cross-platform, which means that you can bump an Android phone with an iPhone and it should work seamlessly.