TestImage
or the analysis of image processing routines one often needs simulated - pseudoexperimental - images with known properties (e.g. angular orientation or the structural state of the particle image), but additional noise or random orientations. Test Image allows to create such images.
Usage
This logic creates simulated pseudoexperimental images. It can randomly add noise and shift and rotate images. The logic does not generate an image (like a disk) on its own without an input; for this purpose use the logic: CreateImage.
Parameters and I/O
| Parameters | Description |
|---|---|
| copy | How many copies of the input images are generated. Each copy of the image undergoes different noise addition, shifting and rotation from the specified randomization range. |
| Noise Filter High Freq | Gaussian high frequency cut-off for the applied noise (between 0 to 1). |
| Noise Filter Low Freq | Gaussian low frequency cut-off for the applied noise (between 0 to 1). |
| Noise Filter Transmission | Transmission below the High Freq noise Gaussian filter (between 0 to 1). |
| inputSigma | Standard deviation (sigma) of the input image's grey values. The input images are not really normalized, since the grey value mean remains unchanged, yet the standard deviation (sigma) of the image can be adjusted with this option. |
| noiseMean | Mean of the noise. |
| noiseSigma | Standard deviation of the noise. |
| noiseType | gauss: Gaussian noise; uniform: Uniform noise. |
| randomRotHigh | Upper boundary for random image in-plane rotation angle (degrees). |
| randomRotLow | Lower boundary for random image in-plane rotation angle (degrees). |
| randomTransX | Maximum shifting in X direction for random image shifting (pixels). |
| randomTransY | Maximum shifting in Y direction for random image shifting (pixels). |
| seed | Random seed. If set as 0, the result would be totally random, which means not reproducible at all. In case that the result shall be reproducible, choose a number unequal 0, and use the same number next time. |
| snr | Signal to noise ratio. Notice that if it is set as 0 or 1, no noise would be added. |
| New/Changed Header Values | Description |
|---|---|
| rndRotation | In-plane rotation applied to the image. |
| rndXShift | X shift applied to the image. |
| rndYShift | Y shift applied to the image. |