Multimedia communications software with network streaming and multi-format conferencing

• US 6,839,734 B1
• Filed: 09/21/1998
• Issued: 01/04/2005
• Est. Priority Date: 09/21/1998
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Pfenning, Thomas, Ryan, Donald R., Vega-Garcia, Andres, Clark, Michael, Han, Mu, Byrisetty, Rajeev, Solomon, Stefan
• Primary Examiner(s): Harvey, Jack B.
• Assistant Examiner(s): PRIETO, BEATRIZ
• Application Number:
  US09/157,884
• Time in Patent Office: 2,297 Days
• Field of Search: 709/203, 709/204, 379/93.21, 379/96, 379/88.13, 379/93.09, 379/202, 379/158, 379/202.1, 348/15, 348/330, 348/329, 348/972, 348/118, 455/6.3, 455/31.1, 370260-263, 340/825.24, 340/825.25, 345733-747, 375/147
• US Class Current: 709/204
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/4046 with distributed floor control
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]

Abstract

Computers, particularly personal computers, have become everyday communications devices, nearly as common as telephones and televisions. A big reason for this is the expansion of computer networks, such as the Internet, which allow sending and receiving information, including audio and video information, from one computer to one or more other computers. Communicating audio and video information between computers can be problematic because users have to wait for the information to be fully downloaded before viewing or hearing it and because different computers sometimes communicate using incompatible communications protocols, which prevents comprehension. Accordingly, the inventors devised new methods, software, and computer systems that support interactive data streaming (real-time exchange of multimedia data) and full-duplex communications, for example, network conferencing, using more than one communications protocol.

Claims

1. A system in a network conferencing environment for delivering a plurality of video or audio signals, the system comprising:

a plurality of transmitters configured to transmit a set of data streams onto a network, wherein the set of data streams is generated from the plurality of video or audio signals, the audio signals containing useful information and silences or background, and wherein at least one of the transmitters includes a silence suppressor for removing the silences or background while continuing to transmit the useful information from the data streams of the audio signals transmitted by the said at least one transmitter; and

at least one receiver for receiving the set of data streams from the network and recovering the data streams into audio or video signals, the receiver including a demultiplexer for dynamically selecting a subset of the set of data streams based on a source identifier and a payload type and two or more receiver payload handler modules and two or more corresponding decoder modules for handling and decoding two or more types of the data streams.

2. The system of claim 1 wherein one of the payload handler modules handles audio G.711 data and another handles audio G.723.1 data and one or more of the decoder modules decodes audio G.711 data and another decodes audio G.723.1 data.

3. The computer system of claim 2 wherein the demultiplexer is operatively coupled to the one or more decoders for routing data to one of the decoders based on the source identifier and the payload type.

4. The computer system of claim 1 further including an audio mixer operatively coupled to the two or more corresponding decoders.

5. The computer system of claim 1 further including a media rendering module operatively coupled to the one or more decoders.

6. The computer system of claim 1 wherein one or more of the payload handlers includes:

means for reassembling or combining two or more data packets, means for reordering data packets, means for detecting and rejecting duplicate data packets, or means for computing and compensating delay jitter.

7. The system of claim 1, wherein the data streams in the selected subset are most recently activated data steams.

8. The system of claim 1, wherein the source identifier is a synchronization source identifier (SSRC).