All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class feature.OpticalFlow

java.lang.Object
   |
   +----feature.OpticalFlow

public class OpticalFlow

extends Object

Author:

Di Zhong (Columbia University)

flow

Optical flow data array
flow[i][j][0] - x-displacement of pixel(j,i), >99.0 means invalid ;
flow[i][j][1] - y-displacement of pixel(j,i), >99.0 means invalid ;
Note original point is the upper left corner of the bounding box given at constructor.

MIN_ERROR

minimum abserr between two matching blocks before stoping search
Default value is 1.0

OpticalFlow(float[][], float[][], Rectangle, int, int, int)

Compute optical flow of the first image (inside bounding box if given) against the second one
Using 3 iteration hierarchical block based estimation algorithm

saveNeedleMap(String, int)

Save optical flow as a PGM file showing motion vectors

 public float flow[][][]

Optical flow data array
flow[i][j][0] - x-displacement of pixel(j,i), >99.0 means invalid ;
flow[i][j][1] - y-displacement of pixel(j,i), >99.0 means invalid ;
Note original point is the upper left corner of the bounding box given at constructor.

See Also:

OpticalFlow

 public static float MIN_ERROR

minimum abserr between two matching blocks before stoping search
Default value is 1.0

 public OpticalFlow(float img1[][],
                    float img2[][],
                    Rectangle bbox,
                    int step,
                    int srange,
                    int mrad)

Compute optical flow of the first image (inside bounding box if given) against the second one
Using 3 iteration hierarchical block based estimation algorithm

Parameters:

img1 - the first image (Note: it will be modified)

img2 - the second image (Note: it will be modified)

bbox - bounding box in img1 (null: whole frame)

step - step size at the first round (~8), has to be 2^n

srange - searching range at the first round (~7)

mrad - radius of matching block (~12)

 public void saveNeedleMap(String fname,
                           int step)

Save optical flow as a PGM file showing motion vectors

Parameters:

fname - output file name

step - sampling step

See Also:

ImageData, ImageIO

All Packages  Class Hierarchy  This Package  Previous  Next  Index