Abstract: According to one aspect, a printer supports transparency operations by generating mask data at interpretation stage which indicates whether each bit of a page content would be determined by the result of a raster operation or a prior destination value. The mask data can be used to complete quickly rendering of a page image once the rendering starts. Another aspect enables color fills of objects to be performed efficiently. A raster operations engine may determine whether all the points (pixels) of the object would have the same value if the raster operation is performed. If all pixels would have the same value, the value for only one pixel is computed and used for multiple pixels of the object. According to another aspect, when a pattern is to be tiled on an entire image portion, the pattern data is stored in a memory and provided as an input to rendering operation multiple times.

Abstract: According to one aspect, a printer supports transparency operations by generating mask data at interpretation stage which indicates whether each bit of a page content would be determined by the result of a raster operation or a prior destination value. The mask data can be used to complete quickly rendering of a page image once the rendering starts. Another aspect enables color fills of objects to be performed efficiently. A raster operations engine may determine whether all the points (pixels) of the object would have the same value if the raster operation is performed. If all pixels would have the same value, the value for only one pixel is computed and used for multiple pixels of the object. According to another aspect, when a pattern is to be tiled on an entire image portion, the pattern data is stored in a memory and provided as an input to rendering operation multiple times.

Abstract: A printer controller in which the image data received in indexed format is stored only in indexed format. The image data is converted to long format when required for rendering operations by using an appropriate lookup table. By storing the image data only in indexed format until the time of rendering, the memory requirements within a system may be minimized. According to another aspect of the present invention, floating point operations (providing higher precision) may be used in a interpreter block and fixed point operations (providing more speed) may be used in a rendering block, while avoiding/reducing image artifacts in upscaled images. A check is performed to determine whether a pixel in the upscaled image maps back to fall within the boundary of the source image, and corrective action is taken if the pixel does not fall within the boundary.

Abstract: A printer controller in which the image data received in indexed format is stored only in indexed format. The image data is converted to long format when required for rendering operations by using an appropriate lookup table. By storing the image data only in indexed format until the time of rendering, the memory requirements within a system may be minimized. According to another aspect of the present invention, floating point operations (providing higher precision) may be used in a interpreter block and fixed point operations (providing more speed) may be used in a rendering block, while avoiding/reducing image artifacts in upscaled images. A check is performed to determine whether a pixel in the upscaled image maps back to fall within the boundary of the source image, and corrective action is taken if the pixel does not fall within the boundary.

Abstract: According to one aspect, a printer supports transparency operations by generating mask data at interpretation stage which indicates whether each bit of a page content would be determined by the result of a raster operation or a prior destination value. The mask data can be used to complete quickly rendering of a page image once the rendering starts. Another aspect enables color fills of objects to be performed efficiently. A raster operations engine may determine whether all the points (pixels) of the object would have the same value if the raster operation is performed. If all pixels would have the same value, the value for only one pixel is computed and used for multiple pixels of the object. According to another aspect, when a pattern is to be tiled on an entire image portion, the pattern data is stored in a memory and provided as an input to rendering operation multiple times.

Abstract: In accordance with the present invention, defective switches of a switch array are first detected by a control and diagnostic processor by counting the transitions of actual data before and after it is transmitted through an individual switch. In addition, a generator supplies a binary test signal to idle switches, and the number of transitions of the test signal at the input of the switch is compared with the number of transitions at the switch output. If the number of transitions at the switch input and output are not the same, the switch is deemed defective, and an operator is informed of the defective switch identity. In addition, input lines to the defective switch are rerouted to a switch in a redundant or auxiliary switch array. Further, output lines coupled to the defective switch are replaced by the output lines of the redundant array.