IMAGE FILTERS EXAMPLE - ALL FILTERS
The Zoomify Image Viewer included in the Enterprise edition supports the ability
to apply image filters to any Zoomify Image. Filters are applied using simple
sliders or buttons - or check boxes for filters that are simply on or off.
Supported filters include Brightness, Contrast, Sharpness, Blurriness, Color Red, Color Green, Color Blue,
Color Range Red, Color Range Green, Color Range Blue, Gamma, Gamma Red, Gamma Green, Gamma Blue,
Hue, Saturation, Lightness, White Balance, Noise, Grayscale, Threshold, Inversion, Edges, and Sepia.
The order in which filters are applied is relevant to the effect achieved.
The Filter Panel is displayed using HTML parameters corresponding to the desired filter(s) name(s). Alternatively,
the HTLM parameter zImageFiltersVisible can be used with specific group names to easily enable sets of filters.
Available group options include All, Creative, HSL, Pathology, Colors, Color Ranges, and Gamma Colors.
This example demonstrates the setting zImageFiltersVisible=all. This choice is primarily for demonstration purposes
as the entire set of filters is unlikely to be required in common uses. See the additional image filter examples for other
grouping that are more relevant to typical uses. Further information is available in the Parameter List document in the
Documentation folder as well as in the User's Guide and in the JavaScript source code (Enterprise edition).
Note that the complex image processing required for the Sharpness and Blurriness filters does not currently
allow a smooth slider motion. For this reason, these filters are implemented when the mouse is released from the
slider, rather than while the slider is being dragged. This interaction minimizes processing and delivers a more
responsive filtering experience.
The image filter support of the Zoomify Image Viewer is implemented using the Canvas functionality of newer browsers. Alternative
algorithms for several are under consideration, along with potential use of WebGL. As always, input is appreciated.