Viewer Parameter > viewer > viewer.restore_previouszoom

viewer.restore_previouszoom_doubletap

Sets whether to restore the previous zoom ratio when the user double-taps the screen.

Values

true	Restores the previous zoom ratio(The default value)
false	Applies the zoom ratio set in the viewer.zoombydoubletap_printsize parameter

Reference

Applies only if the "viewer.viewmode" parameter value is one of "fittoframe", "fittowidth", and "fittocontents".

If the parameter value is true and you do not change the zoom ratio after running the viewer, the previous zoom ratio is 100 percent based on the print size.

HTML5JS viewer is only supported in Mobile.