Detection of gradual transitions in video sequences

A method of processing a sequence of video frames with a physical computing device to detect a gradual transition between frames, the method comprising the physical computing device performing processing operations of:

• for each of a plurality of frames in the sequence, calculating a measure of the monotonicity of the direction of intensity variations between the frame and other frames in the sequence, thereby generating a temporal sequence of intensity change monotonicity measure values comprising a respective intensity change monotonicity measure value for each of the plurality of frames;
• and
• processing the intensity change monotonicity measure values to detect monotonicity measure values within the temporal sequence representative of a gradual transition between video frames;
• wherein each of the plurality of frames is processed by the physical computing device to calculate a measure of the monotonicity of the direction of intensity variations between the frame and other frames in the sequence by the physical computing device performing processing operations of:
• comparing the intensity values of pixels within the frames to calculate differences therebetween;
• determining signs of the calculated differences;
• and
• processing the determined signs to generate the measure of the monotonicity of the direction of intensity variations.

Apparatus operable to process a sequence of video frames to detect a gradual transition between frames, the apparatus comprising:

• a monitoring measure calculator operable to calculate, for each of a plurality of frames in the sequence, a measure of the monotonicity of the direction of intensity variations between the frame and other frames in the sequence to generate a temporal sequence of intensity change monotonicity measure values comprising a respective intensity change monotonicity measure value for each of the plurality of frames;
• and
• a transition detector operable to process the intensity change monotonicity measure values to detect monotonicity measure values within the temporal sequence representative of a gradual transition between video frames;
• wherein the monotonicity measure calculator is operable to process each of the plurality of frames to calculate a measure of the monotonicity of the direction of intensity variations between the frame and other frames in the sequence by:
• comparing the intensity values of pixels within the frames to calculate differences therebetween;
• determining signs of the calculated differences;
• and
• processing the determined signs to generate the measure of the monotonicity of the direction of intensity variations.

A computer-readable medium having computer-readable instructions stored thereon that, if executed by a computer, cause the computer to perform processing operations comprising:

• for each of a plurality of frames in the sequence, calculating a measure of the monotonicity of the direction of intensity variations between the frame and other frames in the sequence, thereby generating a temporal sequence of intensity change monotonicity measure values comprising a respective intensity change monotonicity measure value for each of the plurality of frames;
• and
• processing the intensity change monotonicity measure values to detect monotonicity measure values within the temporal sequence representative of a gradual transition between video frames;
• wherein each of the plurality of frames is processed to calculate a measure of the monotonicity of the direction of intensity variations between the frame and other frames in the sequence by:
• comparing the intensity values of pixels within the frames to calculate differences therebetween;
• determining signs of the calculated differences;
• and
• processing the determined signs to generate the measure of the monotonicity of the direction of intensity variations.