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## Screen
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Defines the number of available pixels of the used screen real estate. For instance, the [Multitaction](https://www.multitaction.com/) tangible tables we're mostly using are specified as being Full-HD, i.e. screen size is 1920 by 1080 pixels.
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## Camera
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The TUIO protocol transmits the position of objects on the table as normalised coordinates, i.e. instead of being expressed in pixels they are ranging from **0**, i.e. fully left/top to **1**, fully right/bottom. The rigid construction of the [Multitaction](https://www.multitaction.com/) tables ensures that the camera coordinate system and the screen coordinate system are locked, i.e. the won't shift or scale with respect to each other. On the other hand, for *Do-It-Yourself* tables with build in projector and camera, both coordinate systems are always slightly misaligned and out of scale. TULIP incorporates a calibration function to correct those misalignments and stores the corrective factors in the **`camera`** section of the calibration file. Usually, you don't have to edit those values yourself.
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The [TUIO](http://tuio.org/) protocol transmits the position of objects on the table as normalised coordinates, i.e. instead of being expressed in pixels they are ranging from **0**, i.e. fully left/top to **1**, fully right/bottom. The rigid construction of the [Multitaction](https://www.multitaction.com/) tables ensures that the camera coordinate system and the screen coordinate system are locked, i.e. the won't shift or scale with respect to each other. On the other hand, for *Do-It-Yourself* tables with build in projector and camera, both coordinate systems are always slightly misaligned and out of scale. TULIP incorporates a calibration function to correct those misalignments and stores the corrective factors in the **`camera`** section of the calibration file. Usually, you don't have to edit those values yourself.
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## Table
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This section defines a number of table related dimensions. The **`width`** and **`height`** properties define the table's screen dimensions expressed in **millimetres**. Another set of strictly table related properties are **`movementThreshold`** and **`rotationThreshold`**. Tangible tables rely on optical recognition of fiducial markers on the table. This process is by its very nature *noisy*, meaning that detected positions and orientations are not stable for stationary objects, but show slight variations over time, a phenomenon commonly known as *jitter*. Depending on the table you're using, the camera system already provides filters to minimise the amount of jitter. Settings those filters always is a compromise between responsiveness and jitter free.
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