# Interactive White Board

The primary goal of MyScript Interactive Ink (iink) SDK is to let users input and edit their handwriting on a screen surface or a sheet of paper. Interactive White Boards (IWBs) can also support iink but with some specific tuning.

Below we explain why this tuning is necessary and how to proceed.

## Engine internal model

A small ink circle can be an actual circle, a capital “O”, a small “o”, a Chinese dot or even a dot, depending on how “big” it is. Therefore, MyScript iink needs to have a sense of “scale” to perform better recognition and help the engine favor the right hypothesis in ambiguous cases.

The MyScript engine handles everything in millimeters. Its settings correspond to a tablet screen or a sheet of paper. So, in a diagram, the engine expects arrowheads to measure at most a few millimeters, not centimeters. In a usual setup, the ink resolution and the capture surface size allow to retrieve this physical size from the ink coordinates.

## IWB ink specificities

When it comes to IWB, users are writing on a larger screen, with a less precise stylus. All the attendees must be able to distinguish the ink written on the board. So, ink inputs (letters, shapes or symbols) are larger than in classical use cases. Their sizes also depend on users writing habits. The MyScript technology may lack accuracy recognizing them. In most cases, they will be too large for the engine. As it is not the only parameter at stake, it may work but less reliably.

## Tuning Dpi values

To address the IWB ink specificities, you need to find the right dpi values. You should start from your actual hardware (screen size, stylus precision) and writing habits (how big users write on a board). This is the “resolution” of your interactive white board, that will provide the recognizer with a sense of “writing scale” and help favor the right hypotheses. There is no pre-defined procedure to determine these values. So, you should try and test a set of different values. You will therefore find through trials and tests the one leading to the best recognition results.

## Choosing the right content type

Ideal for brainstorming and meetings, an interactive whiteboard enabled with MyScript iink allows participants to draw, write and annotate without a pre-defined semantic structure on a large canvas.

In such a use case, when you want to write freely without structuring your board, we recommend you using a “Raw Content” part configured with interactive features. In conjunction with the lasso selection and hand tools, your users will be able to select areas or blocks within the board, to apply actions on them such as moving or resizing them, copying/pasting, or converting them…

By default, the interactive features are not enabled in “Raw Content” parts. But our Demo sample has been configured to support those features, so you can draw on it: For further details, take a look at the enableRawContentConversion extension function of the Configuration class in the Demo. You may adapt it to tune the configuration according to your specific needs.

## Text guides

When using a “Text” part, you should also check your text guide configuration: As explained in the editing part, text guides improve the recognition accuracy, provided that handwriting uses them as baselines. If handwriting does not match the guides, however, the quality of the recognition can be negatively impacted. With IWB according to users writing habits, you might have to turn them off.

## Diagram text size

When using a “Diagram” part containing text, you should probably enable the diagram.convert.match-text-size setting to ensure a better readibilty to your IWB users. If activated, Diagram typeset text size will be computed to match handwritten ink size on convert. This parameter is set to false by default, so we advise you to set it to true. In addition, the diagram.convert.text-size-scale value is then used to determine the typeset size. The default value is 1.25. Relevant values are within range 1 to 2. The larger the scale, the less font sizes are used. The closer to 1, the most linear the scale is, thus using more font sizes. For large screen like IWBs, it might be relevant to increase the scale value around 2.0. But this also depends on your content, so you might tune this scale value to your device screen and content.