EFFICIENT SYSTEMS AND METHODS FOR TRANSMITTING COMPRESSED VIDEO DATA HAVING DIFFERENT RESOLUTIONS

• US 20070147804A1
• Filed: 03/08/2007
• Published: 06/28/2007
• Est. Priority Date: 06/04/2001
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Zhang, Ji, Liu, Humphrey
• Granted Patent: US 8,817,870 B2
• Time in Patent Office: Days
• US Class Current: 386/232
• CPC Class Codes: H04B 1/66 for reducing bandwidth of signals; for improving efficiency of transmission H04B1/68 takes precedence
• CPC Class Codes: H04N 19/39 involving multiple description coding [MDC], i.e. with separate layers being structured as independently decodable descriptions of input picture data
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/234363 by altering the spatial resolution, e.g. for clients with a lower screen resolution
• CPC Class Codes: H04N 21/2365 Multiplexing of several video streams
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities

Abstract

The present invention relates to systems and methods for combining compressed video data encoded or received with different resolutions. The present invention combines the compressed video data from the two separate bitstreams without decoding and re-encoding each bitstream. To do so, the present invention determines which compressed video bitstream has video data with a lower resolution, and applies a tiling process that alters the low resolution compressed video data such that it may be displayed at a high resolution.

Claims

1. A system for providing a bitstream including compressed video data, the system comprising:

a tiling apparatus that receives first compressed video data at a low resolution, and outputs tiled first compressed video data such that it is displayable using a high resolution; and

a combiner that receives the tiled first compressed video data displayable using the high resolution and receives second compressed video data at the high resolution, and combines the tiled first compressed video data and the second compressed video data together to provide an output bitstream including the tiled first compressed video data and the second compressed video data.

2. The system of claim 1 wherein the tiling apparatus comprises a static video data generator that generates static compressed video data displayable using the high resolution.

3. The system of claim 2 wherein the tiling apparatus comprises a tiler that combines the first compressed video data at the low resolution and the static compressed video data from the static video data generator.

4. The system of claim 3 wherein the static video data generator includes a compressed static video data buffer.

5. The system of claim 3 further comprising a scan controller that selects high resolution macroblocks that the tiler tiles using macroblocks from the first compressed video data or the static compressed video data.

6. The system of claim 1 wherein the tiling apparatus receives third compressed video data at a third resolution, and outputs the tiled first compressed video data such that it is displayable at the third resolution.

7. A method for transmitting a bitstream comprising compressed video data, the method comprising:

receiving first compressed video data at a low resolution;

receiving second compressed video data at a high resolution;

converting the first compressed video data such that it is displayable using the high resolution; and

combining the converted first compressed video data and the second compressed video data into an output compressed bitstream including compressed video data at the high resolution.

8. The method of claim 7 wherein converting the first compressed video data comprises combining the first compressed video data with additional compressed video data such that the first compressed video data and the additional video data is displayable at the high resolution.

9. The method of claim 8 wherein the bitstream is an MPEG-2 compressed bitstream.

10. The method of claim 9 wherein combining the first compressed video data with additional video data is performed by tiling macroblocks from the first compressed video data and macroblocks from the additional compressed video data.

11. The method of claim 10 wherein the additional video data includes static video data macroblocks.

12. The method of claim 11 further including determining the size of a low resolution border around a set of macroblocks included in a frame of the first compressed video data.

13. The method of claim 12 wherein macroblocks from the first compressed video data are tiled within the low resolution border and macroblocks from the additional video data are tiled outside the low resolution border.

14. The method of claim 7 wherein converting the first compressed video data such that it is displayable using the high resolution is performed in real time.

15. The method of claim 7 further including transcoding the output compressed bitstream.

16. The method of claim 7 wherein combining the converted first compressed video data and the second compressed video data into the output compressed bitstream includes splicing the converted first compressed video data and the second compressed video data.

17. The method of claim 7 wherein combining the converted first compressed video data and the second compressed video data into the output compressed bitstream includes remultiplexing the converted first compressed video data and the second compressed video data.

18. The method of claim 17 further including inserting pan-and-scan information into the compressed bitstream.

19. A method for transmitting a bitstream comprising MPEG-1, MPEG-2 or MPEG-4 compressed video data, the method comprising:

receiving first MPEG-1, MPEG-2 or MPEG-4 compressed video data at a low resolution;

receiving second MPEG-1, MPEG-2 or MPEG-4 compressed video data at a high resolution;

converting the first compressed video data such that it is displayable using the high resolution without decoding the first compressed video data; and

combining the converted first compressed video data and the second compressed video data into an output compressed bitstream including MPEG-1, MPEG-2 or MPEG-4 compressed video data that is displayable at the high resolution.

20. The method of claim 19 further including determining the size of a low resolution border around a set of macroblocks included in a frame of the first compressed video data.

21. The method of claim 20 further comprising tiling macroblocks from the first compressed video data and macroblocks from the additional compressed video data.

22. The method of claim 21 wherein macroblocks from the first compressed video data are tiled within the low resolution border and macroblocks from the additional video data are tiled outside the low resolution border.

23. A system for transmitting a bitstream comprising compressed video data, the system comprising:

means for receiving first compressed video data at a low resolution;

means for receiving second compressed video data at a high resolution;

means for converting the first compressed video data such that it is displayable at the high resolution; and

means for combining the converted first compressed video data and the second compressed video data into an output compressed bitstream including compressed video data that is displayable at the high resolution.

24. The system of claim 23 wherein said means for converting the first compressed video data such that it is displayable at the high resolution comprises a video data generation means for generating additional compressed video data.

25. The system of claim 24 wherein said means for converting the first compressed video data such that it is displayable at the high resolution comprises assembling means for combining the first compressed video data and the additional compressed compressed video data.

26. A computer readable medium including instructions for transmitting a bitstream comprising compressed video data, the instructions comprising:

instructions for receiving first compressed video data at a low resolution;

instructions for receiving second compressed video data at a high resolution;

instructions for decoding the compressed video stream at the low resolution;

instructions for converting the first compressed video data such that it is displayable at the high resolution; and

instructions for combining the converted first compressed video data and the second compressed video data into an output compressed bitstream including compressed video data that is displayable at the high resolution.