Error Level Analyser
From Tiny Appz
| Error Level Analyser | |
 | |
| Written By: | Noah |
|---|---|
| Download 408 downloads ^ | |
| Finds error levels from jpg compression in images | |
[edit] Description
It's supposed to be a simple implementation of an error level analyzer as described in section 3.4.2 of this paper.
There are two functions:
If you load an image and hit 'Work', it will create a heat map showing when each pixel changes as jpeg quality decreases from 100 to 0. In this mode, a change is by default considered relevant once the sum of the changes to the r, g, and b values exceeds 10. If you would like to use a threshold other than 10, simply type it into the text box on the toolbar.
If, after loading an image, you move the track bar, the difference for a particular compression level will be shown. Each tick is five levels, going from 0 on the left to 100 on the right. By default the differences will be exaggerated by a factor of 10 to highlight differences. If you wish to using a color scaling factor other than 10 simply type it into the text box on the toolbar.
[edit] Usage
- Load = Load an image - brings up standard load dialog
- Save = Save the image being displayed - brings up standard save dialog
- Work = Generate a heat map
- Trackbar = Display diff for a specific compression level
- Text box = In heat map mode, the change threshold. In diff mode, the color scaling factor.
