Methods and systems for encoding real time multimedia data

• US 6,674,803 B1
• Filed: 02/29/2000
• Issued: 01/06/2004
• Est. Priority Date: 02/20/1998
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Kesselring, William David
• Primary Examiner(s): RAO, ANAND SHASHIKANT
• Application Number:
  US09/515,689
• Time in Patent Office: 1,407 Days
• Field of Search: 375/240-5-2, 348/461-467
• US Class Current: 375/240.26
• CPC Class Codes: H04N 21/23608 Remultiplexing multiplex streams, e.g. involving modifying time stamps or remapping the packet identifiers
• CPC Class Codes: H04N 21/242 Synchronization processes, e.g. processing of PCR [Program Clock References] arrangements for synchronising broadcast or distribution via plural systems in broadcast distribution systems H04H20/18

Abstract

Methods and systems are provided for generating a real time multimedia data stream with accurate time stamps for decoding. Time stamps are provided which compensate for a difference between a video frame rate corresponding to a video frame within the real time multimedia data stream and the oscillator clock. The video frame is then stamped with the time stamp which compensates for the difference between the theoretical presentation time stamp corresponding to the video frame and the oscillator clock.

Claims

1. A method of generating an encoded real time multimedia data stream comprising the steps of:

determining a time stamp which compensates for a difference between a video frame rate corresponding to a video frame within the real time multimedia data stream and the oscillator clock; and

stamping the video frame with the time stamp which compensates for the difference between the theoretical presentation time stamp corresponding to the video frame and the oscillator clock.

2. The method of claim 1, wherein the real time multimedia data stream complies with the MPEG2 standard.

3. A system for generating an encoded real time multimedia data stream comprising:

means for determining a time stamp which compensates for a difference between a video frame rate corresponding to a video frame within the real time multimedia data stream and the oscillator clock; and

means for stamping the video frame with the time stamp which compensates for the difference between the video frame rate corresponding to the video frame and the oscillator clock.

4. The system according to claim 3, wherein the real time multimedia data stream complies with the MPEG2 standard.

5. A computer program product for generating an encoded real time multimedia data stream comprising:

a computer-readable storage medium having computer-readable program code means embodied in said medium, said computer-readable program code means comprising;

computer readable program code means for determining a time stamp which compensates for a difference between a video frame rate corresponding to a video frame within the real time multimedia data stream and the oscillator clock; and

computer readable program code means for stamping the video frame with the time stamp which compensates for the difference between the video frame rate corresponding to the video frame and the oscillator clock.

6. The computer program product according to claim 5, wherein the real time multimedia data stream complies with the MPEG2 standard.