The Noise Dissolve filter dissolves an image by adding a pattern of noise to it. Raising the value of the Dissolve Amount parameter gradually eats away at more and more of the image. The alpha channel is set to zero within the noisy areas, so background images are revealed as the Dissolve Amount increases.
Adjust this filter using the parameter controls in the Filters Inspector:
Dissolve Amount: Sets the percentage of pixels dissolved by noise.
Random Seed: Sets a number to be used as a seed for noise placement.
Mix: Sets the percentage of the original image to be blended with the filtered image.