how to change step between images in a viewer? (Java/Icy)

dear all,

just a quick question. I would like to play a stack of images with the standard viewer not image by image (ie 0, 1, 2, 3, … N), but with a step that the user can change (for ex. 0, 10, 20, …). The button that starts the play is a right arrowhead. Is it on the viewer class, on the canvas? is there a parameter or a value that I could change from with a plugin in Java?

The reason for this is that we are developing a plugin to analyze our data, which are stack of jpg images originating from timelapse captures. Instead of analyzing our time series image by image, it is often enough to analyze only 1 image under 10 or 1 under 60 (we capture 1 image per minute). The results of our analysis can be displayed on the images via rois. However, these rois are only on 1/10 (or 1/60) of the images. It would be easier for us to verify the quality of the analysis by clamping the viewer to display only the analyzed images..

Thank you in advance for any suggestion,

fred