There are two types of conferences:
1. when each SIP device plays N-1 streams and sends N-1 streams, where N is totla number of SIP devices connected to the conference. This can be implemented, but it will take long and the cost will be pricey too. 2. When each SIP device plays and sends just one stream containing mixed videos of all participants. This works as long as there's a third-party mixing SIP-server.
In the second case, several Flashphoner clients connect via SIP to one mixing server and then connect to the video conference.
3. There's also a way to do this without SIP - when browsers simply exchange Flash or WebRTC streams.
Regarding the second option: Let's say we have a SIP video conference. There are 2 users from web-pages (powered by Flashphoner) and 2 SIP-devices via hardware or software SIP-phones.
There's also a mising server. Each participant of the conference makes a video call to this mixing server. Think of it as if they just go all together in the same room on the mixing server, and the server merges the picture into one video stream. That is, a user sees the conference as a split-screen video, where every part displays video of the corresponding user.
As a result, when a participant reaches the conference, he sees the rest participants, three in our case. if he called from a webpage (using Flashphoner), he also sees all three participants.
For example, if we have the following layout:
User1 Flash FLASHPHONER MIXING-SERVER User3_Bria_softphone
User2 Flash User4_Grandstream_hardware_phone In this layout User3 and User4 call to the MIXING-SERVER directly.
User1 and User2 call from the webpage via Flashphoner.
It is getting clear now. 1. In theory, can I make so that one participant (let's say a lecturer) could see all others (let's say students)? Students can't see each other, but do see the lecturer. The lecturer sees everyone.
2. Can you suggest such a MIXING-SERVER? If this a flashphoner technology?
3. Can I run such a video conference using Flashphoner?
3. Yes, it is possible with Flashphoner Web Call Server. You can send streams and play streams from other web-clients. Based on this functionality, you can implement just any logic you need.
The thing is, we need a cross-platform video chat client. Including mobile platforms. That's why we selected your product, as you are the only developer offering that (or we didn't find others). We plan to develop from scratch, the entire app.
Can we use Web Call Server to implement this? Including the 1-to-many conference?
In the mean time, I study your product, that's why I'm asking these questions. They are important to me now, and it seems i received my answers. Here is a brief input data:
We need to develop a videochat call-center system.
Base requirements are: cross-platform (partial), slow connection networks support. A translator is on one side of the line, with a listener on the other side (1 to 1) or a group of listeners (1to many).
We have made a beta based on Flash.
We also have a version for Android tablets using AIR. It works well within the sam network, but talking about mobile networks - it looks pathetic. So i googled your website.
We need SIP top manage these calls and sessions, like redirect a session to another translator, put on hol etc. Cross-platform is our concern. The iea is you have a product that does what we need (and it seems it does, but need more testing).
What can you say?
1. You can implement support for conferences in Flashphoner without mixing. In this case the conference is straight exchange of WebRTC streams many-to-many between each other. 2. operation in networks with bad connection.
This is all about quality real-time delivery of the video from a 3G device to the network server and back. The latest public codec I know of is VP8(WebRTC) that can be adopted to the bandwidth.