Abstract: The present disclosure describes apparatuses and techniques for using an image-based monitoring and feedback system for three-dimensional printing. In some aspects, a camera captures images of objects being printed and an image-processing system compares the images with benchmark images to detect and correct differences between the object and the benchmark. The correction can be in real time or applied to subsequent printing. Other aspects include a calibration system that prints predefined test objects and compares them to benchmarks to ensure that the printer operating parameters are properly set. The comparison can be manually performed by a user or automated as a part of the image-processing system.

Abstract: Methods of determining a known location of a sensor head in a scanner without the use of contact sensors are described. Upon initialization of a scanner, the sensor head is moved rapidly to quickly detect a known pattern at a known location in the scanner. As the scan head is moved, windows moving along lines of pixels detected by the sensor head are used to perform pixel averaging to detect the known pattern in the scanner. Parameters associated with the windows custom fit the windows to the known pattern to facilitate rapid detection of the known pattern and determine a known location of the scan head to facilitate calibration of the scanner.

Abstract: An exemplary device includes: a scanner capable of beginning a scan of a scanning target and providing timing-related information for the scan; and a printer capable of printing an image of the scanning target and receiving the timing-related information, the printer including a print engine; wherein the printer is adapted to activate the print engine prior to receiving all scan lines of the scanning target responsive to the timing-related information. An exemplary method for accelerating printing includes actions of: beginning a scan of a scanning target; determining timing-related information from the scan; and sending an instruction to a print engine responsive to the timing-related information and prior to completing the scan.

Abstract: A system for designating individual paper holders in printers and copiers that use interchangeable paper holders, paper cassettes, paper trays and the like. The invention provides a paper supply which is capable of automatically changing its identifying indicia dependent upon its position within a group of similar paper supplies. For example, if a paper tray was positioned in the third position within a stack of paper trays, it would automatically adjust its identifying indicia to reflect that it is the "third" paper tray. Using the invented designation system, the paper holders may be automatically designated according to their placement in the printer or copier. The system includes a movable designator, typically a number designator, connected to and viewable on the paper holder. The designator is operable to move between two positions. When the designator is in the first position, the designator is not visible on the paper holder.

Abstract: The present invention receives the output of a polygon clipper process and determines which lines are extraneous. This determination is accomplished by keeping a list of all potential extraneous lines. When a new line is generated, it is compared to all lines in the list. If the new line overlaps any of the lines in the list, both lines are shortened to remove the overlap. After the new line has been checked and any necessary modifications made, any lines remaining are placed into the list to be compared to future lines. After the polygon clipper and extraneous line eliminator have completed processing the polygon, the output of the clipper and the list are combined to complete the description of the clipped polygon.