Error recovery using alternate reference frame

Patent metadata

Field	Value
Publication number	US-10616576-B2
Application number	US-201213599360-A
Country	US
Kind code	B2
Filing date	Aug 30, 2012
Priority date	May 12, 2003
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

A system, apparatus, and method for decoding a video signal having a plurality of frames including a current frame. Decoding the video signal includes generating an alternate reference frame, detecting an error in the current frame and reporting the detected error, receiving a recovery frame in response to reporting the detected error, wherein the recovery frame is encoded using the alternate reference frame; and decoding the recovery frame using the alternate reference frame. The alternate reference frame occurs prior to the current frame in the video signal and is other than a frame immediately prior to the current frame.

First claim

What is claimed is:

1. A method for encoding an input video signal, by a processor in response to instructions stored on a non-transitory computer readable medium, the method comprising:
generating a first encoded frame by encoding a first frame from the input video signal;
transmitting the first encoded frame to an external decoder;
generating a first reconstructed frame by decoding the first encoded frame;
generating a second encoded frame by encoding a second frame from the input video signal, wherein encoding the second frame includes:
using the first reconstructed frame as a reference frame to encode the second frame;

transmitting the second encoded frame to the external decoder;
generating a second reconstructed frame by decoding the second encoded frame;
generating a third encoded frame by encoding a third frame from the input video signal, wherein encoding the third frame includes:
using the second reconstructed frame as a reference frame to encode the third frame;

transmitting the third encoded frame to the external decoder;
generating a third reconstructed frame by decoding the third encoded frame;
generating a fourth encoded frame by encoding a fourth frame from the input video signal, wherein encoding the fourth frame includes:
using the third reconstructed frame as a reference frame to encode the fourth frame;

transmitting the fourth encoded frame to the external decoder;
receiving, from the external decoder, an error report indicating an error associated with decoding the third encoded frame;
generating a fifth encoded frame by encoding a fifth frame from the input video signal, wherein encoding the fifth frame includes:
in response to receiving the error report, selecting a reference frame for encoding the fifth frame from a group consisting of the first reconstructed frame; and
in response to selecting the reference frame for encoding the fifth frame from the group consisting of the first reconstructed frame, using the selected reference frame to encode the fifth frame; and

transmitting the fifth encoded frame to the external decoder.

2. The method of claim 1 , wherein generating the fifth encoded frame includes identifying the first encoded frame as an alternate reference frame.

3. The method of claim 2 , further comprising:
generating a key frame; and
updating at least a portion of the alternate reference frame with at least a portion of the key frame.

4. The method of claim 2 , wherein the alternate reference frame is updated periodically.

5. The method of claim 4 , wherein the alternate reference frame is updated periodically every X seconds.

6. The method of claim 4 , wherein the alternate reference frame is updated periodically every F frames.

7. The method of claim 2 , wherein the error is at least one of data loss or data corruption.

8. A method for decoding an encoded video stream, by a processor in response to instructions stored on a non-transitory computer readable medium, the method comprising:
receiving a first portion of the encoded video stream from an external encoder;
generating a first reconstructed frame by decoding a first encoded frame from the first portion of the encoded video stream;
generating a second reconstructed frame by decoding a second encoded frame from the first portion of the encoded video stream, wherein decoding the second encoded frame includes:
using the first reconstructed frame as a reference frame for decoding the second encoded frame;

generating a third reconstructed frame, wherein generating the third reconstructed frame includes:
detecting an error associated with decoding a third encoded frame from the first portion of the encoded video stream;
generating an error report indicating the error;
transmitting the error report to the external decoder; and
generating, as the third reconstructed frame, an error concealed frame by performing error concealment based on the second reconstructed frame;

generating a fourth reconstructed frame by decoding a fourth encoded frame from the first portion of the encoded video stream, wherein decoding the fourth encoded frame includes:
using the third reconstructed frame as a reference frame for decoding the fourth encoded frame, such that the fourth reconstructed frame includes a propagation error corresponding to the error concealment;

receiving a second portion of the encoded video stream from the external encoder;
generating a fifth reconstructed frame by decoding a fifth encoded frame from the second portion of the encoded video stream, wherein decoding the fifth encoded frame includes:
using the first reconstructed frame as a reference frame for decoding the fifth encoded frame, on a condition that the fifth encoded frame is a frame encoded by selecting a reference frame for encoding the fifth frame from a group consisting of the first reconstructed frame; and

outputting the first reconstructed frame, the second reconstructed frame, the third reconstructed frame, the fourth reconstructed frame, and the fifth reconstructed frame for presentation or storage.

9. The method of claim 8 , wherein generating the fifth reconstructed frame includes identifying the first reconstructed frame as an alternate reference frame.

10. The method of claim 9 , wherein the alternate reference frame is updated periodically.

11. The method of claim 10 , wherein the alternate reference frame is updated periodically every X seconds.

12. The method of claim 10 , wherein the alternate reference frame is updated periodically every F frames.

13. The method of claim 8 , wherein detecting the error includes detecting at least one of data loss or data corruption.

14. The method of claim 9 , wherein receiving the second portion of the encoded video stream includes receiving a frame header including a flag bit indicating an update of the alternate reference frame, the method further comprising:
updating at least a portion of the alternate reference frame in response to receiving the frame header including the flag bit.

Assignees

• Ameres Eric
• Bankoski James
• Lavarnway Scott
• Xu Yaowu
• Miller Dan
• Grange Adrian
• Wilkins Paul
• Google Llc

Inventors

• Ameres Eric
• Bankoski James
• Lavarnway Scott
• Xu Yaowu
• Miller Dan
• Grange Adrian
• Wilkins Paul

Classifications

• H04N19/129

  Scanning of coding units, e.g. zig-zag scan of transform coefficients or flexible macroblock ordering [FMO] · CPC title

• H04N19/152

  by measuring the fullness of the transmission buffer · CPC title

• H04N19/114

  Adapting the group of pictures [GOP] structure, e.g. number of B-frames between two anchor frames (H04N19/107 takes precedence) · CPC title

• H04N19/139

  Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability · CPC title

• H04N19/14

  Coding unit complexity, e.g. amount of activity or edge presence estimation (H04N19/146 takes precedence) · CPC title