Advancing playback of video data based on parameter values of video data

• US 20020110358A1
• Filed: 02/09/2001
• Published: 08/15/2002
• Est. Priority Date: 02/09/2001
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Green, Dustin
• Granted Patent: US 7,035,526 B2
• Time in Patent Office: Days
• US Class Current: 386/68
• CPC Class Codes: G11B 27/28 by using information signals recorded by the same method as the main recording G11B27/22 takes precedence
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/4325 by playing back content from the storage medium reproduction of recorded television signals H04N5/76; reproduction of recorded television signals H04N9/79
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/4345 Extraction or processing of SI, e.g. extracting service information from an MPEG stream
• CPC Class Codes: H04N 21/44008 involving operations for analysing video streams, e.g. detecting features or characteristics in the video stream arrangements characterised by components specially adapted for monitoring, identification or recognition of video in broadcast systems H04H60/59
• CPC Class Codes: H04N 21/478 Supplemental services, e.g. displaying phone caller identification, shopping application
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream
• CPC Class Codes: H04N 21/8456 by decomposing the content in the time domain, e.g. in time segments
• CPC Class Codes: H04N 5/782 on tape

Abstract

A digital video data system automatically skips the playback of recorded video data to a position that corresponds to a transition between segments of the video data. Positions that are candidates for being segment transitions are identified by quantifying the rate of change of one or more parameters of the video data at multiple positions and determining positions for which the rate of change is locally maximal. Parameters such as luminance, I-frame frequency, and frame size tend to change most rapidly at segment transitions. Information relating to the change in the parameter values is stored with recorded video data so that it can be used to identify segment transitions during playback of the video data. During playback, and in response to user input, the system selects a position where the rate of change of parameter values is locally maximal and skips playback to that position.

Claims

1. In an entertainment system that is capable of playing back stored video data, wherein the video data is characterized by parameters that vary as a function of time within the video data, a method of skipping the playback of video data to a location selected to approximate a segment transition between segments of the video data, the method comprising the acts of:

playing back stored video data, wherein the video data includes information identifying positions in the video data that are candidates for segment transitions, the candidates for segment transitions having been identified based on a comparison of values representing the change of the value of a parameter of the video data at a plurality of positions in the video data;

skipping the playback of the video data to a location in the video data designated to approximate a segment transition between segments of the video data, by performing the acts of;

selecting one of the candidates for segment transitions as the location to which the playback is to be skipped; and

skipping the playback to the selected location and resuming playing back of video data from the selected location.

2. A method as defined in claim 1, further comprising, prior to the act of playing back the stored video data, the act of identifying the positions in the video data that are candidates for segment transitions by quantifying the rate of change in the value of the parameter of the video data at the plurality of positions in the video data.

3. A method as defined in claim 2, wherein the act of quantifying the change in the value of a parameter of the video data includes performing, for each of the plurality of positions, the acts of:

calculating a preceding local average value of the parameter in a portion of the video data preceding the position;

calculating a following local average value of the parameter in a portion of the video data following the position; and

generating a local average difference value by calculating the absolute value of the difference between the preceding local average value and the following local average value.

4. A method as defined in claim 3, wherein positions having a locally maximal local average difference value are identified as being candidates for segment transitions.

5. A method as defined in claim 1, wherein the information identifying positions in the video data that are candidates for segment transitions comprises transition tags inserted into the video data at the positions that are candidates for segment transitions, the transition tags having been inserted by the entertainment system after the entertainment system receives the video data.

6. A method as defined in claim 1, wherein the information identifying positions in the video data that are candidates for segment transitions has been inserted into the video data by an encoder prior to the entertainment system receiving the video data, the information having been inserted into the video data by the encoder performing the acts of:

calculating a preceding local average value of the parameter in a portion of the video data preceding the position;

calculating a following local average value of the parameter in a portion of the video data following the position;

generating a local average difference by calculating the absolute value of the difference between the preceding local average value and the following local average value; and

inserting information relating to the local average difference into the video data.

7. A method as defined in claim 1, wherein the act of selecting one of the candidates for segment transitions comprises the acts of:

at each of a plurality of positions that are candidates for segment transitions, multiplying the value representing the rate of change of the value of the parameter at the position with a corresponding value selected from a weighting curve, the shape and position of the weighting curve being selected to favor the selection of a candidate for segment transition that is positioned at a default skip length from a current playback position in the video data to generate a product value associated with the position; and

selecting the position having the greatest associated product value.

8. A method as defined in claim 7, wherein the weighing curve defines a Gaussian distribution having an apex at the default skip length.

9. A method as defined in claim 1, further comprising the act of receiving input from a user requesting the playback to be skipped, the act of skipping the playback of the video data being initiated in response to the act of receiving input.

10. A method as defined in claim 1, wherein the candidates for segment transitions have been identified based on a comparison of values representing the change of the value of multiple parameters of the video data at a plurality of positions in the video data

11. A method as defined in claim 1, wherein the parameter is selected from a group of parameters consisting of:

frame size;

luminance of an image encoded in the video data; and

overall quantization scale used to encode the color of the image.

12. A method as defined in claim 1, wherein:

the video data is encoded using a compression format that uses interframe decoding and includes periodic intraframes used in interframe decoding; and

the parameter represents a frequency of the intraframes in the video data.

13. A method as defined in claim 1, further comprising the act of receiving and storing the video data at the entertainment system for later playback of the video data.

15. A method as defined in claim 14, wherein the act of selecting one of the candidates comprises the acts of:

at each of a plurality of candidate positions in the video data, multiplying the value representing the change of the value of the parameter at the position with a corresponding value selected from a weighting curve, the shape and position of the weighting curve being selected to favor the selection of a candidate for segment transition that is positioned at a default skip length from a current playback position in the video data to generate a product value associated with the position; and

selecting the position having the greatest associated product value.

16. A method as defined in claim 15, wherein the default skip length is thirty seconds.

17. A method as defined in claim 15, wherein candidate positions that fall at locations in the weighting curve at which the weighting curve has value 0 are not considered or multiplied by the weighting curve.

18. A method as defined in claim 15, wherein the act of identifying segment transition candidates comprises the act of generating the candidates, including the acts of:

calculating a preceding local average value of the parameter in a portion of the video data preceding the position;

calculating a following local average value of the parameter in a portion of the video data following the position; and

generating a local average difference by calculating the absolute value of the difference between the preceding local average value and the following local average value.

19. A method as defined in claim 18, wherein the act of identifying positions in the video data that are candidates for segment transitions comprises the act of identifying positions having a local average difference that is a local maximum.

20. A method as recited in claim 15, wherein the act of storing values representing the change of the value of a parameter of the video data at a plurality of positions in the video data comprises the act of receiving the stored values with the video data, the values having been generated by an encoder of the video data performing the acts of:

calculating a preceding local average value of the parameter in a portion of the video data preceding the position;

calculating a following local average value of the parameter in a portion of the video data following the position; and

generating a local average difference by calculating the absolute value of the difference between the preceding local average value and the following local average value.

14. In an entertainment system that is capable of playing back stored video data, wherein the video data is characterized by parameters that vary as a function of time within the video data, a method of skipping the playback of video data to a location selected to approximate a segment transition between segments of the video data, the method comprising the acts of:

storing video data that has been received by the entertainment system;

calculating values representing the rate of change of the value of a parameter of the video data at a plurality of positions in the video data;

identifying positions in the video data that are candidates for segment transitions by comparing the values representing the change of the value of the parameter at a plurality of positions in the video data;

storing with the video data the segment transition candidates;

playing back the video data;

receiving input from a user requesting that the playback be skipped to a segment transition between segments of the video data;

in response to the input, selecting one of the candidates for segment transitions as the location to which the playback is to be skipped; and

skipping the playback to the selected location and resuming playing back of video data from the selected location.

21. In a video encoder that encodes video data in a compressed format in preparation for transmitting the video data to an entertainment system, wherein the encoded video data is characterized by parameters that vary as a function of time within the video data, a method of supplementing the video data with information identifying candidates for segment transitions between segments of the video data, the method comprising:

encoding the video data in the compressed format;

including, with the video data, information representing the change in the value of a parameter by performing the acts of;

calculating a preceding local average value of the parameter in a portion of the video data preceding the position;

calculating a following local average value of the parameter in a portion of the video data following the position;

generating a local average difference by calculating the absolute value of the difference between the preceding local average value and the following local average value; and

inserting information relating to the local average difference into the video data; and

transmitting the video data and the information representing the change in the value of the parameter to a decoder included in an entertainment system such that the entertainment system can skip playback of the video data to a segment transition in the video data.

22. A method as defined in claim 21, wherein the parameter is selected from a group of parameters consisting of:

frame size;

luminance of an image encoded in the video data; and

overall quantization scale used to encode the color of the image.

23. A method as defined in claim 21, wherein:

the video data is encoded using a compression format that uses interframe decoding and includes periodic intraframes used in interframe decoding; and

the parameter represents a frequency of the intraframes in the video data.

24. A method as defined in claim 21, wherein the act of identifying positions in the video data that are candidates for segment transitions comprises the act of comparing values representing the change in the values of multiple parameters of the video data, including performing, for each of the multiple parameters, the acts of:

calculating a preceding local average value of the parameter in a portion of the video data preceding the position;

calculating a following local average value of the parameter in a portion of the video data following the position;

generating a local average difference value by calculating the absolute value of the difference between the preceding local average value and the following local average value; and

identifying local maxima in the local average difference values over time.

26. A computer program product as recited in claim 25, wherein the act of selecting one of the candidates comprises the acts of:

at each of a plurality of candidate positions in the video data, multiplying the value representing the change of the value of the parameter at the position with a corresponding value selected from a weighting curve, the shape and position of the weighting curve being selected to favor the selection of a candidate for segment transition that is positioned at a default skip length from a current playback position in the video data to generate a product value associated with the position; and

selecting the position having the greatest associated product value.

27. A computer program product as defined in claim 26, wherein the weighing curve defines a Gaussian distribution having an apex at the default skip length.

28. A computer program product as defined in claim 25, wherein the act of storing values representing the change of the value of a parameter of the video data at a plurality of positions in the video data comprises the act of generating the stored values, including the acts of:

calculating a preceding local average value of the parameter in a portion of the video data preceding the position;

calculating a following local average value of the parameter in a portion of the video data following the position; and

generating a local average difference by calculating the absolute value of the difference between the preceding local average value and the following local average value.

25. A computer program product for implementing, in an entertainment system that is capable of playing back stored video data, wherein the video data is characterized by parameters that vary as a function of time within the video data, a method of skipping the playback of video data to a location selected to approximate a segment transition between segments of the video data, the computer program product comprising:

executable instructions for implementing the method, the executable instructions, when executed, causing the entertainment system to perform the acts of;

storing video data that has been received by the entertainment system;

calculating values representing the rate of change of the value of a parameter of the video data at a plurality of positions in the video data;

identifying positions in the video data that are candidates for segment transitions by comparing the values representing the change of the value of the parameter at a plurality of positions in the video data;

storing with the video data the segment transition candidates;

playing back the video data;

receiving input from a user requesting that the playback be skipped to a segment transition between segments of the video data;

in response to the input, selecting one of the candidates for segment transitions as the location to which the playback is to be skipped; and

skipping the playback to the selected location and resuming playing back of video data from the selected location.