Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>As the comment on your question says, UDP or other streaming protocols are usually preferred. But with WCF providing more abstraction, would be easier to do something like this. Having said that I have implemented a voice chatting feature on one of our previous software (the software was used by multiple clients in a LAN) with WCF and <code>netTcpBinding</code>, and it worked well (I tested it with 5 clients in a LAN), you couldn't really feel that WCF hindered the architecture. It will get interesting with the release of WCF 4.5 which will be supporting UDP transport.</p> <p>For something like this, you should really get the gist of duplex communication in WCF. I went about with doing in such a way that i had a <code>SendVoice()</code> operation contract on my service, everytime a client sent their asudio stream to the service, the <code>SendVoice()</code> method would iterate through the list of subscribers (connected clients) and invoke the <code>SendVoiceCallback()</code> on each client. You could start with something like this:</p> <pre><code>public void SendVoice(byte[] audio) { //Keep a list of connected clients in a dictionary called subscribers //lock your subscribers list so that it's not modified when you're in the middle of sending the stream lock (subscribers) { //send the received voice stream to each client foreach (var _subscriber in subscribers) { if (OperationContext.Current.GetCallbackChannel&lt;IVoiceChatCallback&gt;() == subscriber.Key) { //if the person who sent the video is the current subscriber then don't send the video to THAT subscriber continue; } try { //Send the received stream to the client asynchronously _subscriber.Key.BeginOnVoiceSendCallback(audio, onNotifyCompletedVoiceSend, _subscriber.Key); } catch (Exception) { //fault handling } } } } </code></pre> <p>Your clients would then call the method above periodically, in my implementation I set this to every 250 milliseconds and it worked perfectly well (obviously there was a small lag). </p> <p>In the code above <code>IVoiceChatCallback</code> is the callback contract. Callbacks enable the service to invoke some operation on the clients, so for an isntance the client will behave like a server. Asynchronous service calls will mean that your <code>SendVoice()</code> will publish the audio to every client asynchronously, rather than waiting for the previous stream to reach the client before sending the new stream.</p> <p>The code above is just an idea for you to get started. You should add some fault handling code to the service to check when clients are disconnected and remove them from your subscribers dictionary. Again You should become comfortable with asynchronous operation calls in WCF as well as callbacks. Also if you're looking to use this in LAN, then <code>netTcpBinding</code> is the way to go, and you should configure your service as to optimise its throughput and concurrency. Over the internet, you'd want to use a Http Binding that supports duplex.</p>
    singulars
    1. This table or related slice is empty.
    1. POhow to start a WCF voice chat application?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USMohammad Sepahvand
    1. USMohammad Sepahvand
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POhow to start a WCF voice chat application?
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThanks for your great answer, can my portable application be the self-host and the client in the same time ?? or i have to make two separated application (client/self-host service)?
      singulars
      1. PO
      1. USMurhaf Sousli
    2. CO@Mur Haf Soz, I'm not sure I understand, care to eleboarte a bit more? Do you mean can your service host also be a client? Sure why not. My idea is to have a 'main' service that was in charge of sending each clients stream to the other in the form of a callback, so each client sends their voice to the main service, the main service would then invoke a callback on each client (basically play the audio stream received from the service). If you want me to be more specific, I can update my answer.
      singulars
      1. PO
      1. USMohammad Sepahvand
    3. COyea, i would love to know more.
      singulars
      1. PO
      1. USMurhaf Sousli
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload