Dynamic trans-framing and trans-rating for interactive playback control

• US 7,643,422 B1
• Filed: 03/24/2006
• Issued: 01/05/2010
• Est. Priority Date: 03/24/2006
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Shen, Bo, Roy, Sumit, Covell, Michele
• Primary Examiner(s): Nguyen; Brian D
• Application Number:
  US11/389,401
• Time in Patent Office: 1,383 Days
• Field of Search: 370/235, 370/230, 370/230.1, 370/231, 709/231, 709/226, 709/229
• US Class Current: 370/235
• CPC Class Codes: H04L 65/613 for the control of the source by the destination control signals issued by the client directed to the server or network components specially adapted for selective content distribution H04N21/637
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/756 adapting media to device capabilities
• CPC Class Codes: H04L 65/762 at the source reformatting of additional data in video distribution servers H04N21/2355
• CPC Class Codes: H04N 21/234381 by altering the temporal resolution, e.g. decreasing the frame rate by frame skipping
• CPC Class Codes: H04N 21/6131 involving transmission via a mobile phone network wireless downlink channel access H04W74/006
• CPC Class Codes: H04N 21/6373 for rate control , e.g. request to the server to modify its transmission rate flow control in packet networks H04L47/10
• CPC Class Codes: H04N 21/6377 directed to server one-way streaming services wherein the source is controlled by the destination H04L65/613
• CPC Class Codes: H04N 21/658 Transmission by the client directed to the server
• CPC Class Codes: H04N 21/6587 Control parameters, e.g. trick play commands, viewpoint selection

Abstract

Embodiments of the present invention recited a method and system for modifying a media stream. In one embodiment, a request is received to modify a media stream from a current display rate to a desired display rate. In response to the request, the media stream dynamically processed to create a modified media stream which is compliant with a pre-determined frame-rate limitation and with a pre-determined bit-rate limitation.

Claims

1. A computer implemented method for modifying a media stream, said method comprising:

receiving a request at said computer to modify a media stream from a current display rate to a desired display rate; and

dynamically processing at said computer said media stream to create a modified media stream which is compliant with a pre-determined frame-rate limitation and with a pre-determined bit-rate limitation, wherein said dynamically processing said media stream further comprises;

determining a desired frame-rate in response to receiving said request;

determining a desired frame-time for each of a plurality of data frames in accordance with said desired frame-rate;

determining a corresponding output presentation time for each of said plurality of data frames; and

modifying a first of said plurality of data frames if the output presentation time for said first data frame is at least equal to the desired frame-time for a second data frame immediately succeeding said first data frame unless said second data frame comprises an intra-coded frame (I-frame).

2. The computer implemented method as recited in claim 1 wherein said first data frame and said second data frame comprise predictive-coded frames (P-frames) and wherein said modifying comprises:

dropping said first data frame; and

re-encoding said second data frame to remove any dependencies on said first data frame.

3. The computer implemented method as recited in claim 1 wherein said first data frame comprises a predictive-coded frame (P-frame) and said second data frame comprises an intra-coded frame (I-frame) and wherein said modifying comprises:

dropping said first data frame; and

presenting said second data frame in the output presentation time of said first data frame.

4. The computer implemented method as recited in claim 1 wherein said first data frame comprises an intra-coded frame (I-frame) and said second data frame comprises a predictive-coded frame (P-frame) and wherein said modifying comprises:

dropping said first data frame; and

re-encoding said second data frame as an intra-coded frame (I-frame).

5. The computer implemented method as recited in claim 1 wherein dynamically processing said media stream further comprises:

determining whether said modified media stream exceeds said pre-determined bit-rate limitation in response to said modifying.

6. The computer implemented method as recited in claim 5 further comprising;

determining a ratio between an average number of bits in a plurality of predictive-coded frames (P-frames) of said media stream and an average number of bits in a plurality of intra-coded frames (I-frames) of said media stream;

determining an average group of pictures (GOP) length of said media stream;

determining whether said modified media stream exceeds said pre-determined bit-rate limitation; and

reducing the bit-rate of said modified media stream to comply with said pre-determined bit-rate limitation.

7. An interactive media stream system comprising:

a media access device for displaying a media stream; and

a media stream generating device communicatively coupled with said media access device, said media stream generating device for receiving a request to modify said media stream from a current display rate to a desired display rate and for dynamically processing said media stream in response to said request to create a modified media stream which is compliant with a pre-determined frame-rate limitation and with a pre-determined bit-rate limitation and wherein said dynamically processing said media stream comprises;

determining a desired frame-rate in response to receiving said request;

determining a desired frame-time for each of a plurality of data frames in accordance with said desired frame rate;

determining a corresponding output presentation time for each of said plurality of data frames; and

modifying a first data frame of said plurality of data frames if the output presentation time for said first data frame is at least equal to the desired frame-time for a second data frame immediately succeeding said first data frame unless said second data frame comprises an intra-coded frame (I-frame).

8. The system of claim 7 wherein said first data frame and said second data frame comprise predictive-coded frames (P-frames) and wherein said media stream generating device drops said first data frame and re-encodes said second data frame to remove any dependencies on said first data frame.

9. The system of claim 7 wherein said first data frame comprises a predictive-coded frame (P-frame) and said second data frame comprises an intra-coded frame (I-frame) and wherein said media stream generating device drops said first data frame and presents said second data frame in the output presentation time of said first data frame.

10. The system of claim 7 wherein said first data frame comprises an intra-coded frame (I-frame) and said second data frame comprises a predictive-coded frame (P-frame) and wherein said media stream generating device drops said first data frame and re-encodes said second data frame as an intra-coded frame (I-frame).

11. The system of claim 7 wherein dynamically processing said media stream further comprises:

determining whether said modified media stream exceeds said pre-determined bit-rate limitation in response to said modifying.

12. The system of claim 11 wherein said dynamically processing further comprises;

determining a ratio between an average number of bits in a plurality of predictive-coded frames (P-frames) of said media stream and an average number of bits in a plurality of intra-coded frames (I-frames) of said media stream;

determining an average group of pictures (GOP) length of said media stream;

determining whether said modified media stream exceeds said pre-determined bit-rate limitation; and

reducing the bit-rate of said modified media stream to comply with said pre-determined bit-rate limitation.

13. A media stream generating system comprising:

a component for receiving a request to modify a media stream from a current display rate to a desired display rate; and

a media stream modifying device for dynamically processing said media stream to create a modified media stream which is compliant with a pre-determined frame-rate limitation and with a pre-determined bit-rate limitation, wherein said media stream modifying device implements a frame-rate transcoding process comprising;

determining a desired frame-rate in response to receiving said request;

determining a desired frame-time for each of a plurality of data frames in accordance with said desired frame rate;

determining a corresponding output presentation time for each of said plurality of data frames; and

modifying a first of said plurality of data frames if the output presentation time for said first data frame is at least equal to the desired frame-time for a second data frame immediately succeeding said first data frame unless said second data frame comprises an intra-coded frame (I-frame).

14. The system of claim 13 wherein said first data frame and said second data frame comprise predictive-coded frames (P-frames) and wherein said media stream modifying device drops said first data frame and re-encodes said second data frame to remove any dependencies on said first data frame.

15. The system of claim 13 wherein said first data frame comprises a predictive-coded frame (P-frame) and said second data frame comprises an intra-coded frame (I-frame) and wherein said media stream modifying device drops said first data frame and presents said second data frame in the output presentation time of said first data frame.

16. The system of claim 13 wherein said first data frame comprises an intra-coded frame (I-frame) and said second data frame comprises a predictive-coded frame (P-frame) and wherein said media stream modifying device drops said first data frame and re-encodes said second data frame as an intra-coded frame (I-frame).

17. The system of claim 13 wherein said media stream modifying device further implements a bit-rate transcoding process comprising:

determining whether said modified media stream exceeds said pre-determined bit-rate limitation in response to said modifying.

18. The system of claim 17 wherein said bit-rate transcoding process further comprises;

determining a ratio between an average number of bits in a plurality of predictive-coded frames (P-frames) of said media stream and an average number of bits in a plurality of intra-coded frames (I-frames) of said media stream;

determining an average group of pictures (GOP) length of said media stream;

determining whether said modified media stream exceeds said pre-determined bit-rate limitation; and

reducing the bit-rate of said modified media stream to comply with said pre-determined bit-rate limitation.