Method for reconstructing a video frame received from a video source over a communication channel

• US 6,289,297 B1
• Filed: 10/09/1998
• Issued: 09/11/2001
• Est. Priority Date: 10/09/1998
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bahl, Paramvir
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): Sergent, Douglas W.
• Application Number:
  US09/169,093
• Time in Patent Office: 1,068 Days
• Field of Search: 703/2, 348/384, 348/466, 370/442, 375/240, 375/240.01, 375/240.11, 375/240.19, 375/240.27, 714/798, 714/48, 382/233, 382/236, 382/240
• US Class Current: 703/2
• CPC Class Codes: H04N 19/10 using adaptive coding
• CPC Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• CPC Class Codes: H04N 19/18 the unit being a set of transform coefficients
• CPC Class Codes: H04N 19/20 using video object coding
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets
• CPC Class Codes: H04N 19/66 involving data partitioning, i.e. separation of data into packets or partitions according to importance
• CPC Class Codes: H04N 21/23655 Statistical multiplexing, e.g. by controlling the encoder to alter its bitrate to optimize the bandwidth utilization

Abstract

An adaptive region-based, multi-scale, motion compensated video compression algorithm design for transmission over hostile communication channels. The algorithm is embodied in a video encoder that extracts spatial information from video frames to create video regions that are then decomposed into sub-bands of different perceptual importance before being compressed and transmitted independently. The system further uses unequal error protection, prioritized transmission and reconstruction to guarantee a minimum spatial and temporal resolution at the receiver. In particular, the region segmented frames bound both spatial and temporal error propagation within frames. A connection-level inter-region statistical multiplexing scheme is also employed to ensure optimal utilization of reserved transmission bandwidth.

Claims

1. A method for reconstructing a video frame received from a video source over a communication network, the method comprising the steps of:

receiving from the video source a first plurality of transmissions over the communications network wherein each transmission contains information representative of a discrete spatial component corresponding to a particular region of a first video frame;

receiving from the video source a second plurality of transmissions over the communications network wherein each transmission contains information representative of a discrete spatial component corresponding to a particular region of a second video frame;

determining if a transmission error is associated with any of the second plurality of transmissions;

substituting for each of the second plurality of transmissions that is determined to have an associated error the information contained in one of the first plurality of transmissions to thereby form a reconstructed second video frame; and

requesting that the video source give priority to a particular transmission in a third plurality of transmissions, wherein each transmission in the third plurality of transmissions contains information representative of a discrete spatial component corresponding to a particular region of a third video frame, wherein the requested priority is a function of the determined errors associated with the second plurality of transmissions.

2. The method as recited in claim 1 wherein the step of determining if a transmission error is associated with any of the second plurality of transmissions further comprises the step of examining the content of the second plurality of transmissions.

3. The method as recited in claim 1 wherein the step of determining if a transmission error is associated with any of the second plurality of transmissions further comprises the step of evaluating the timing of the second plurality of transmissions.

4. The method as recited in claim 1 further comprising the step of storing in memory the information representative of the first video frame.

5. The method as recited in claim 4 further comprising the step of replacing in memory the information representative of the first video frame with the information representative of the reconstructed second video frame.

6. A computer-readable medium having computer executable instructions for use in reconstructing a video image, the instructions performing steps comprising:

receiving from a video source a first plurality of transmissions over a communications network wherein each transmission contains information representative of a discrete spatial component corresponding to a particular region of a first video frame;

receiving from the video source a second plurality of transmissions over the communications network wherein each transmission contains information representative of a discrete spatial component corresponding to a particular region of a second video frame;

determining if a transmission error is associated with any of the second plurality of transmissions;

substituting for each of the second plurality of transmissions that is determined to have an associated error the information contained in one of the first plurality of transmissions to thereby form a reconstructed second video frame; and

requesting that the video source give priority to a particular transmission in a third plurality of transmissions, wherein each transmission in the third plurality of transmissions contains information representative of a discrete spatial component corresponding to a particular region of a third video frame, wherein the requested priority is a function of the determined errors associated with the second plurality of transmissions.

7. The computer-readable medium as recited in claim 6 wherein the instructions for performing the step of determining if a transmission error is associated with any of the second plurality of transmissions further comprise instructions for performing the step of examining the content of the second plurality of transmissions.

8. The computer-readable medium as recited in claim 6 wherein the instructions for performing the step of determining if a transmission error is associated with any of the second plurality of transmissions further comprise instructions for performing the step of evaluating the timing of the second plurality of transmissions.

9. The computer-readable medium as recited in claim 7 further comprising instructions for performing the step of storing in memory the information representative of the first video frame.

10. The computer-readable medium as recited in claim 9 further comprising instructions for performing the step of replacing in memory the information representative of the first video frame with the information representative of the reconstructed second video frame.