Lexmark International, Inc.

David Allen Crutchfield

Galen Arthur Rasche

Timothy John Rademacher

James Ray Bailey

Adam Jude Ahne

Mark Joseph Edwards

James Alan Ward

Curt Paul Breswick

Christopher Alan Adkins

James Lee Combs

Thomas Jon Eade

Zachary Nathan Fister

Shaun Timothy Love

Stephen Kelly Cunnagin

John Booth Bates

Ronald E Garnett

Christopher Wilson Case

David Vincent Iorio

Bob Thai Pham

Aaron Wendell Billings

A method for generating transposed image data for use in an imaging apparatus having access to a memory includes (a) generating a set of data blocks corresponding to at least a portion of image data representing an image to be printed; (b) performing a combined format and transpose operation on the set of data blocks; and (c) storing a result of the combined format and transpose operation in the memory.

Method for generating transposed image data

A USB host/client system includes a USB host device, a USB client device connected via a USB cable to the USB host device, and a power supply unit remote from the USB host device for powering the USB host device through the USB cable connecting the USB client device to the USB host device. The USB host device can have means for communicating with a computer while the USB host device is connected to a USB client device, and/or the power supply unit supplies sufficient power for all normal operations of the USB host device.

Detecting by USB client device a connection to host USB device wherein power is not supply from host USB device to USB client device

A method for dynamically compensating for a faulty pixel in a scan line of a scanner having an image sensor with a plurality of sensor pixels includes generating digitized scan data; processing the digitized scan data to compensate for any faulty pixels of the plurality of sensor pixels to form compensated scan data; processing the compensated scan data to apply offset and gain correction to the compensated scan data to form calibrated scan data; processing the calibrated scan data to adjust the calibrated scan data to compensate for human visual perception to form final scan data; and storing the final scan data in a scanner image memory.

Method for dynamically compensating for a faulty pixel in a scan line generated by a scanner

Printer () is provided with a mode to edit and print forms without reference to or interruption of a host computer and with immediate printing of one or more of the forms. Page data for the forms is preferably stored in flash memory () in a high level printer language. Preferably, at initiation of the forms mode at least the first listed document is immediately prepared by the control data processor () of the printer in bit mapped form for printing. Documents can be listed on the control panel by name for ready selection for printing.

Quick edit and speed print capability for a stand-alone ink jet printer

A method of transforming a n-bit data packet to a m-bit data packet with a lookup table. The lookup table includes at least one entry data packet and at least one respective delta value associated with each entry data packet. The method includes the acts of receiving an input data packet having n-bits, indexing the lookup table with at least a portion of the input data packet to obtain one of the at least one entry data packet, and decompressing the obtained entry data packet with the at least one respective delta value associated with the obtained entry data packet, thereby resulting in an output data packet having m-bits. The decompressing act includes using a portion of the input data packet to determine the number of delta values called for decompressing the obtained entry data packet. The method can be used in, for example, an image processor.

Method of an image processor for transforming a n-bit data packet to a m-bit data packet using a lookup table

Error diffusion is performed upon input image data. In one aspect, multiple error diffusion processing elements perform error diffusion on a selected pixel in parallel. In another aspect, the error diffusion logic is integrally formed with a fast local memory in the same electronic device, such as an ASIC. The error data produced by the error diffusion logic for a pixel is buffered in the fast local memory until it is to be used by the error diffusion logic on other pixels. In still another aspect, a first-in-first-out (FIFO) buffer regulates or buffers the color image data between the output of a color conversion system, such as a colorant lookup table, and the input an error diffusion processing element. In yet another aspect, the error diffusion logic has tagging logic that produces and stores an indicator, either in the output data stream itself or in a separate area, to indicate whether a raster contains printable data.

Systems and methods for error diffusion

Error diffusion is performed using a Floyd-Steinberg-like approach. A integer-representation of a running error is compressed by storing only its most significant bits and returning any remainder to the error diffusion processor. The running error is shifted to the right until only the desired number of significant bits remain, and this compressed error is stored. Any portion of the original running error that is lost due to the shifting is treated as a remainder and is returned to the error diffusion processor for use in calculating an adjusted current pixel value. The amount of the shift is retained in compressed form to keep track of the number of shifts needed to form a truncated running error from the compressed running error.

System and method for dynamically shifting error diffusion data

A method for effecting synchronous pulse generation for use in serial communications is provided. The method includes the steps of generating a difference signal representing a signal level difference between at least two data stream signals; providing a clock signal; providing a counter, defining a sample count value of the counter; incrementing the counter in relation to the clock signal; and determining whether a current count value of the counter corresponds to the sample count value. If the current count value corresponds to the sample count value, then the method performs a step of generating a synchronous pulse. If the current count value does not correspond to the sample count value, then the method performs a step of determining whether a signal level of said difference signal has changed, and if the signal level of the difference signal has changed then performing a step of ignoring further changes in the signal level of the difference signal until the current count value of the counter corresponds to the sample count value at which time the step of generating the synchronous pulse is repeated.

Method and apparatus for effecting synchronous pulse generation for use in serial communications

The present invention relates to error diffusion logic in which three partial diffusion error values are produced in a pipelined manner and then summed together when the last partial error value is produced. The resulting summed error can be used to adjust a target pixel in a sequence of pixels or stored in a buffer until further corresponding partial error is produced for adjusting the target pixel.

Calculating error diffusion errors to minimize memory accesses

A method for effecting synchronous pulse generation for use in variable speed serial communications is provided. The method includes the steps of obtaining a communication link speed; generating a difference signal representing a signal level difference between at least two data stream signals; providing a clock signal; providing a counter; defining a sample count value of the counter using the communication link speed; incrementing the counter in relation to the clock signal; and determining whether a current count value of the counter corresponds to the sample count value. If the current count value corresponds to the sample count value, then the method performs a step of generating a synchronous pulse. If the current count value does not correspond to the sample count value, then the method performs a step of determining whether a signal level of said difference signal has changed, and if the signal level of the difference signal has changed then performing a step of ignoring further changes in the signal level of the difference signal until the current count value of the counter corresponds to the sample count value at which time the step of generating the synchronous pulse is repeated.

Method and apparatus for effecting synchronous pulse generation for use in variable speed serial communications

A method for effecting synchronous pulse generation for use in serial communications is provided. The method includes the steps of generating a difference signal representing a signal level difference between at least two data stream signals; providing a clock signal; providing a counter; defining a sample count value of the counter; incrementing the counter in relation to the clock signal; and determining whether a current count value of the counter corresponds to the sample count value. If the current count value corresponds to the sample count value, then the method performs a step of generating a synchronous pulse. If the current count value does not correspond to the sample count value, then the method performs a step of determining whether a signal level of said difference signal has changed, and if the signal level of the difference signal has changed then performing a step of ignoring further changes in the signal level of the difference signal until the current count value of the counter corresponds to the sample count value at which time the step of generating the synchronous pulse is repeated.

An improved data acquisition system interface provides virtually constant sampling of input signals and provides those signals in a digitized format to a data acquisition unit that may not be able to sample at a constant rate without missing or 'losing' some of the samples. The present invention acts as a front end interface that temporarily latches the sampled data, expands the data into multiple parallel signals, then stores the multiple parallel signals in a dual-port FIFO memory unit. Finally, the multiple parallel signals are transferred into the data acquisition unit at a lower frequency, and the transfer operations take place only when the data acquisition unit is ready to accept data. Since the front end misses no sampling intervals (i.e., it always takes a sample according to an extremely constant frequency crystal clock), then the data acquisition unit will be provided with all of these samples without losing any data. The only requirement is that the data throughput of the multiple parallel signals into the data acquisition unit be greater than or equal to the data sampling rate of the original signal at the front end. The present invention can be used with pure digital signals to capture their precise times of logic state transitions, or with serial data signals in which the precise moments of transition can be used to decipher the serial data. Moreover, the interface can be used with analog signals that are digitized using an analog-to-digital converter.

Method and apparatus for sampling digital data at a virtually constant rate, and transferring that data into a non-constant sampling rate device

The present invention is directed to systems and methods for formatting hardware for a printhead, for use in a printing device. The systems and methods of the present invention can support the formatting function with hardware formatting logic. This hardware formatting logic can support multiple printhead platforms. The hardware formatting logic of the present invention can perform bit shifting, resolution reduction, bit per pixel reduction, data masking for shingling, and input data sourcing. The present invention can also include a system processor further including an embedded ARM processor which can fetch and execute instructions and/or firmware. These instructions can direct the embedded processor to configure a format block included within the system processor. The format block can be configured by the system processor via one or more control registers.

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Lexington, KY, United States of America

David Allen Crutchfield