A printhead controller controls printing of a page by at least one printhead. The printhead controller, in use, receives data, in a compressed format relating to the page to be printed, the data including a page description comprising a bi-level black layer and a contone color layer. The printhead controller extracts from the compressed data relating to the bi-level black layer the contone color layer. Memory is provided for temporary storage of the expanded data. A dithering/compositing unit pr…

Machine-readable coded data disposed on or in a substrate. The coded data includes a layout having order n rotational symmetry, formed from n identical sub-layouts rotated 1/n revolutions apart about a center of rotation. The layout encodes a first codeword formed from a sequence of a multiple m of n first symbols, with each sub-layout defining respective positions for each of m first symbols, such that the m first symbols uniquely identify each sub-layout. Decoding the first symbols provided at…

Machine-readable coded data disposed on or in a substrate. The coded data includes a plurality of layouts of two or more layout types, each layout having n identical sub-layouts rotated 1/n revolutions apart about a center of rotation. Each layout encodes a first codeword formed from a sequence of n first symbols, each sub-layout defining a position for a respective first symbol so that the first symbol indicates the identity of the sub-layout. The layout also encodes a second codeword formed fr…

A method of generating an interface surface is provided, in which machine-readable coded data is generated in a computer system in accordance with a layout and is printed onto a surface with a printer in communication with the computer system. The layout has at least order n rotational symmetry, where n is at least two, and encodes a fault tolerant orientation codeword comprising a sequence of an integer multiple m of n symbols, where m is one or more. Each encoded symbol is distributed at n loc…

An inkjet pagewidth printer includes a chassis. A print media feed mechanism is mounted on the chassis to feed print media along a feed path. A pair of opposed transfer rollers are rotatably mounted on the chassis to contact the print media as it is moved along the feed path. A displacement mechanism is operatively engaged with the transfer rollers to displace the rollers into and out of engagement with the print media. A pair of opposed pagewidth printhead assemblies is mounted on the chassis t…

Machine-readable coded data disposed on or in a substrate. The coded data includes a plurality of layouts located in a region, each layout having n identical sub-layouts rotated 1/n revolutions apart about a center of rotation. Each layout encoding a first codeword formed from a sequence of n first symbols, with each sub-layout defining the position of a respective one of the first symbols such that the first codeword is indicative of the orientation of the layout. Each layout also partially enc…

Machine-readable coded data disposed on or in a substrate. The coded data includes a plurality of layouts, each having n identical sub-layouts rotated 1/n revolutions apart about a center of rotation. Each layout encodes a first codeword formed from a sequence of n first symbols, each sub-layout defining the position of a respective one of the first symbols such that the first codeword is indicative of the orientation of the layout. In addition, each layout includes a number target features for …

Machine-readable coded data disposed on or in a substrate. The coded data includes a plurality of layouts, each of which has order n rotational symmetry. The layout encodes a first codeword formed from a sequence of n first symbols distributed at n locations about the center of rotational symmetry of the layout. In use, decoding the first symbols at each of the n orientations of the layout produces n representations of the first codeword, with each representation being a different cyclic shift o…

Machine-readable coded data disposed on or in a substrate in accordance with a layout, and method of generating such coded data, The layout has six-fold rotational symmetry and includes 6 identical sub-layouts rotated 1/6 revolutions apart about a center of rotational symmetry of the layout. The coded data is disposed in accordance with each sub-layout including rotation-indicating data that distinguishes the rotation of that sub-layout from the rotation of at least one other sub-layout within t…

Machine-readable coded data disposed on or in a substrate in accordance with a layout, the layout having at least order n rotational symmetry, where n is at least two, the layout encoding an orientation codeword comprising a sequence of an integer multiple m of of n symbols, where m is one or more, each encoded symbol being distributed at n locations about a center of rotational symmetry of the layout such that decoding the symbols at each of the n orientations of the layout produces n represent…