Tool Universal Image Quality Index
The Universal Image Quality Index compares two grids (greyscale images) using the three parameters luminance, contrast and structure. This is done for each pixel using a moving window as specified by the kernel radius.
References
- Lasaponara, R. & Masini, N. (2012): Image Enhancement, Feature Extraction and Geospatial Analysis in an Archaeological Perspective. In: Lasaponara, R. & Masini, N. [Eds.]: Satellite Remote Sensing - A New Tool for Archaeology, S. 17-64. Springer Link.
- Wang, Z. & Bovik, A.C. (2002): A universal image quality index. IEEE Signal Processing Letters, vol.9, no.3, pp.81-84. IEEE-Xplore.
- Author: M.Ambrosi (c) 2017
- Menu: Imagery|Analysis
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | First Grid | grid, input | GRID_A | - | - |
| Second Grid | grid, input | GRID_B | - | - |
| Output | Universal Image Quality Index | grid, output | QUALITY | The product of correlation, luminance and contrast similarity. | - |
| Correlation (*) | grid, output, optional | CORRELATION | The correlation coefficient. | - |
| Luminance (*) | grid, output, optional | LUMINANCE | The similarity of mean luminance. | - |
| Contrast (*) | grid, output, optional | CONTRAST | The similarity of contrast. | - |
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - |
| k1 | floating point number | K1 | - | Minimum: 0.000000
Maximum: 1.000000
Default: 0.010000 |
| k2 | floating point number | K2 | - | Minimum: 0.000000
Maximum: 1.000000
Default: 0.030000 |
| L | integer number | L | The dynamic range for the image pixel, i.e. the number of different grey values. | Minimum: 1
Default: 255 |
| Kernel Type | choice | KERNEL_TYPE | The kernel's shape. | Available Choices:
[0] Square
[1] Circle
Default: 1 |
| Radius | integer number | KERNEL_RADIUS | cells | Minimum: 0
Default: 2 |
| (*) optional |
Command-line
Usage: saga_cmd imagery_tools 13 [-GRID_A <str>] [-GRID_B <str>] [-QUALITY <str>] [-CORRELATION <str>] [-LUMINANCE <str>] [-CONTRAST <str>] [-K1 <double>] [-K2 <double>] [-L <num>] [-KERNEL_TYPE <str>] [-KERNEL_RADIUS <num>]
-GRID_A:<str> First Grid
grid, input
-GRID_B:<str> Second Grid
grid, input
-QUALITY:<str> Universal Image Quality Index
grid, output
-CORRELATION:<str> Correlation
grid, output, optional
-LUMINANCE:<str> Luminance
grid, output, optional
-CONTRAST:<str> Contrast
grid, output, optional
-K1:<double> k1
floating point number
Minimum: 0.000000
Maximum: 1.000000
Default: 0.010000
-K2:<double> k2
floating point number
Minimum: 0.000000
Maximum: 1.000000
Default: 0.030000
-L:<num> L
integer number
Minimum: 1
Default: 255
-KERNEL_TYPE:<str> Kernel Type
choice
Available Choices:
[0] Square
[1] Circle
Default: 1
-KERNEL_RADIUS:<num> Radius
integer number
Minimum: 0
Default: 2