Table 1
Inputs.
| Input files and parameters | Notation | Unit | Note |
|---|---|---|---|
| image pair | Im1, Im2 | – | tif, bmp, jpeg etc. |
| Lagrange multipliers | lambda_1 for the Horn-Schunck estimator lambda_2 for the Liu-Shen estimator | – | regularization parameter in variational solution |
| Gaussian filter size | size_filter | pixel | removing random image noise |
| Gaussian filter size | size_average | pixel | correction for local illumination intensity change |
| scale factor for downsampling of original images | scale_im | – | reduction of initial image size in coarse-to-fine scheme |
| number of iterations | no_iteration | – | iteration in coarse-to-fine scheme |
| indicator for regional diagnostics (0 or 1) | index_region | – | “0” for whole image; “1” for selected region |
Table 2
Outputs.
| Output files | Notation | Unit | Note |
|---|---|---|---|
| coarse-grained velocity | ux0, uy0 | pixels/unit-time | based on downsampled images |
| refined velocity | ux_corr, uy_corr | pixels/unit-time | refined result with full spatial resolution in coarse-to-fine process |
Figure 1
A pair of particle images of an Oseen vortex pair in a uniform flow, (a) Image #1, and (b) Image #2.
Figure 2
Velocity vectors of an Oseen vortex pair in a uniform flow extracted from the particle images, (a) Coarse-grained field, and (b) Refined field.
Figure 3
Streamlines of an Oseen vortex pair in uniform flow extracted from the particle images, (a) Coarse-grained field, and (b) Refined field.
Figure 4
Vorticity field of an Oseen vortex pair in uniform flow extracted from the particle images.
Figure 5
A pair of images of the White Ovals on Jupiter, (a) Image #1, and (b) Image #2.
Figure 6
Velocity vectors of the White Ovals on Jupiter, (a) Coarse-grained field, and (b) Refined field.
Figure 7
Streamlines of the White Ovals on Jupiter, (a) Coarse-grained field, and (b) Refined field.
Figure 8
Vorticity field of the White Ovals on Jupiter.
Figure 9
Quasi 2D turbulence, (a) Sample image, and (b) Vorticity field.
Figure 10
Wall-jet region of an impinging jet, (a) Sample image, and (b) Vorticity field.