Efficient software bitstream rate generator for video server

• US 20030115609A1
• Filed: 09/10/2002
• Published: 06/19/2003
• Est. Priority Date: 09/12/2001
• Status: Active Grant

• Current Assignee: Cox Communications Incorporated (Cox Enterprises Incorporated)
• Original Assignee: Cox Communications Incorporated (Cox Enterprises Incorporated)
• Inventors: Frederickson, James, Taylor, Clement G.
• Granted Patent: US 7,904,931 B2
• Time in Patent Office: Days
• US Class Current: 725/93
• CPC Class Codes: H04N 21/23805 Controlling the feeding rate to the network, e.g. by controlling the video pump
• CPC Class Codes: H04N 21/64769 for rate control flow control in packet networks H04L47/10
• CPC Class Codes: H04N 7/17318 Direct or substantially direct transmission and handling of requests

Abstract

An apparatus and a method for constraining the delivery rate of a plurality of bitstreams, such as MPEG bitstreams using a single software process.

Claims

1. A method, comprising:

retrieving, from a priority queue, a stream deadline element including a respective stream deadline key and stream identifier; and

in the case of the stream deadline key representing a time later than a current time, transmitting at least one packet associated with said identified stream.

2. The method of claim 1, wherein in the case of the stream deadline key not representing a time later than a current time, enabling a processing element to perform an alternate task.

3. The method of claim 2, wherein said alternate task is exited when said stream deadline key represents a time later than said current time.

4. The method of claim 1, further comprising:

calculating, after transmitting said at least one packet, a new deadline of at least one next packet associated with said identified stream; and

inserting, into said priority queue, a new stream deadline element for said identified stream including a respective stream deadline key using said new calculated deadline.

5. The method of claim 4, wherein said new deadline is calculated using the encoded bit rate of the identified stream and said stream deadline element is inserted into the priority queue based upon the relative priority of the at least one next packet.

6. The method of claim 1, further comprising:

calculating, for at least one packet of a new stream to be transmitted, a deadline associated with said new stream; and

inserting, into said priority queue, a new stream deadline element for said new stream including a respective stream deadline key using said new calculated deadline.

7. The method of claim 1, wherein said stream deadline elements operate to provide a rate generator function within a multiple stream delivery system.

8. The method of claim 7, wherein said multiple stream delivery system also comprises a multiple bit rate delivery system.

9. The method of claim 8, wherein streams having a relatively low bit rate are processed less frequently than streams having a relatively high bit rate.

10. The method of claim 1, wherein the priority indicative position of a deadline element within said priority queue is adapted in response to changes in the respective deadline key of the deadline element.

18. The method of claim 1, wherein said stream deadline elements operate to provide a rate generator function within a multiple stream, multiple bit rate delivery system.

11. A method of regulating the delivery time of content, comprising:

arranging content portions of each of a plurality of content streams in a priority queue according to the relative transmission time deadlines of the respective content portions; and

in the case of a highest priority content portion having associated with it a transmission time later than a current time, performing the steps of;

transmitting the highest priority content portion; and

inserting a new content portion into the priority queue according to its relative transmission time deadline, said new content portion comprising a next portion of a content stream including said transmitted content portion.

12. The method of claim 11, further comprising:

inserting a new stream content portion into the priority queue according to its relative transmission time deadline, said new stream content portion comprising a content portion of a new content stream to be transmitted.

13. The method of claim 11, wherein:

in the case of said highest priority content portion having associated with it a transmission time not later than a current time, enabling a processing element to perform an alternate task.

14. The method of claim 13, wherein said alternate task is exited when said stream deadline key represents a time later than said current time.

15. The method of claim 11, further comprising:

calculating, after transmitting said content portion, a new transmission time deadline of at least one next content portion associated with said identified stream; and

inserting, into said priority queue, a new stream deadline element for said identified stream including a respective stream deadline key using said new calculated deadline.

16. The method of claim 15, wherein said new transmission time deadline is calculated using the encoded bit rate of said identified stream.

17. The method of claim 12, further comprising:

calculating, using the encoded bit rate of said new stream, a new transmission time deadline of said new stream content portion using the encoded bit rate of said new stream.

19. A method for use in a video stream server providing a plurality of video steams via respective streaming nodes, said method comprising:

associating at least one packet from each of said video streams with a respective stream deadline element including a respective stream deadline key indicative of a transmission time and a respective stream identifier;

arranging said stream deadline elements in a priority queue according to the relative transmission times indicated by said stream deadline keys; and

in the case of the stream deadline key of the highest priority stream deadline event representing a time later than a current time, transmitting the at least one corresponding packet.

20. The method of claim 19, further comprising:

while the stream deadline key of the highest priority stream deadline event not representing a time later than a current time, enabling a processing element to perform an alternate task.