System and method for selecting key-frames of video data

A method for selecting key-frames from video data, comprising the steps of:

• partitioning video data into segments;
• generating a temporal activity curve for dissimilarity measures based on one of frame differences, color histograms, camera motion, and a combination thereof, for each segment;
• and
• sampling the temporal activity curve to select at least one key-frame for each segment, wherein the step of generating a temporal activity curve for dissimilarity measures based on camera motion comprises the steps of:
• estimating camera motion between consecutive frames in a given segment;
• computing a motion activity curve based on the estimated camera motion for the given segment;
• and
• computing a binary motion activity curve by comparing the motion activity curve to a second predefined threshold on a frame-by-frame basis.

A method for selecting key-frames from video data, comprising the steps of:

• partitioning video data into segments;
• generating a temporal activity curve for dissimilarity measures based on one of frame differences, color histograms, camera motion, and a combination thereof, for each segment;
• and
• sampling the temporal activity curve to select at least one key-frame for each segment, wherein the step of generating a temporal activity curve for dissimilarity measures based on color histograms comprises the steps of:
• computing a color histogram of each frame of a given segment;
• computing a moving average histogram of the given segment using the computed color histograms for each frame;
• generating a color histogram activity curve by computing a distance between the color histogram of each frame and the moving average histogram;
• and
• computing a binary color histogram activity curve by comparing a change in value of the color histogram activity curve between each consecutive frame of the given segment to a fourth predefined threshold value.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for selecting key-frames from video data, the method steps comprising:

• partitioning video data into segments;
• generating a temporal activity curve for dissimilarity measures based on one of frame differences, color histograms, camera motion, and a combination thereof, for each segment, wherein the step of generating a temporal activity curve for dissimilarity measures based on frame differences comprises computing an average of an absolute pixel-based intensity difference between consecutive frames in a given segment, and computing a cumulative sum of the average of the absolute pixel-based intensity differences for the frames of the given segment;
• and
• sampling the temporal activity curve to select at least one key-frame for each segment, wherein the step of sampling the temporal activity curve comprises selecting a first frame in the given segment as a key-frame, if the cumulative sum of the average of the absolute pixel-based intensity differences for the frames of the given segment does not exceed a first predefined threshold, and selecting a predefined number of key-frames in the given segment uniformly, if the cumulative sum of the average of the absolute pixel-based intensity differences for the frames of the given segment exceeds the first predefined threshold.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for selecting key-frames from video data, the method steps comprising:

• partitioning video data into segments;
• generating a temporal activity curve for dissimilarity measures based on one of frame differences, color histograms, camera motion, and a combination thereof, for each segment;
• and
• sampling the temporal activity curve to select at least one key-frame for each segment,
• wherein the instructions for performing the step of generating a temporal activity curve for dissimilarity measures based on camera motion comprise instructions for performing the steps of:
• estimating camera motion between consecutive frames in a given segment;
• computing a motion activity curve based on the estimated camera motion for the given segment;
• and
• computing a binary motion activity curve by comparing the motion activity curve to a second predefined threshold on a frame-by-frame basis.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for selecting key-frames from video data, the method steps comprising:

• partitioning video data into segments;
• generating a temporal activity curve for dissimilarity measures based on one of frame differences, color histograms, camera motion, and a combination thereof, for each segment;
• and
• sampling the temporal activity curve to select at least one key-frame for each segment,
• wherein the instructions for performing the step of generating a temporal activity curve for dissimilarity measures based on color histograms comprise instructions for performing the steps of:
• computing a color histogram of each frame of a given segment;
• computing a moving average histogram of the given segment using the computed color histograms for each frame;
• generating a color histogram activity curve by computing a distance between the color histogram of each frame and the moving average histogram;
• and
• computing a binary color histogram activity curve by comparing a change in value of the color histogram activity curve between each consecutive frame of the given segment to a fourth predefined threshold value.