Digital processing method and system for determination of optical flow

A non-transitory computer-readable storage medium including instructions that, when accessed by a processing system, cause the processing system to perform operations comprising:

• (a) decomposing each of a pair of images into image pyramids;
• (b) transforming the pair of decomposed images at a first pyramid scale to second derivative representations under an assumption that a brightness gradient of pixels in the pair of decomposed images is constant;
• (c) estimating discrete-time derivatives of the second derivative image representations;
• (d) applying an optical flow estimation process to the discrete-time derivatives to produce a raw optical flow field;
• (e) scaling the raw optical flow field;
• and
• (f) repeating steps (b)-(e) for the pair of images at another pyramid scale until all pyramid scales have been visited to produce a final optical flow field, wherein each of the pair of decomposed images of step (b) is warped by using the motion vectors estimated in a previously scaled optical flow estimation.

A method for determining an optical flow field between a pair of images, comprising the steps of:

• (a) decomposing each of the pair of images into image pyramids;
• (b) transforming the pair of decomposed images at a first pyramid scale to second derivative representations under an assumption that a brightness gradient of pixels in the pair of decomposed images is constant;
• (c) estimating discrete-time derivatives of the second derivative image representations;
• (d) applying an optical flow estimation process to the discrete-time derivatives to produce a raw optical flow field;
• (e) scaling the raw optical flow field;
• and
• (f) repeating steps (b)-(e) for the pair of images at another pyramid scale until all pyramid scales have been visited to produce a final optical flow field, wherein each of the pair of decomposed images of step (b) is motion compensated by using motion vectors estimated in a previously scaled optical flow estimation.

A non-transitory computer-readable storage medium including instructions that, when accessed by a processing system, cause the processing system to perform operations comprising:

• (a) decomposing each of a pair of images into image pyramids;
• (b) transforming the pair of decomposed images at a first pyramid scale to second derivative representations under an assumption that a brightness gradient of pixels in the pair of decomposed images is constant;
• (c) estimating discrete-time derivatives of the second derivative image representations;
• (d) applying an optical flow estimation process to the discrete-time derivatives to produce a raw optical flow field;
• (e) scaling the raw optical flow field;
• and
• (f) repeating steps (b)-(e) for the pair of images at another pyramid scale until all pyramid scales have been visited to produce a final optical flow field, wherein each of the pair of decomposed images of step (b) is motion compensated by using motion vectors estimated in a previously scaled optical flow estimation.