Ricoh Company, Ltd.

Guotong Feng

John W Barrus

M Dirk Robinson

Edward L Schwartz

Michael J Gormish

Berna Erol

Bradley J Rhodes

Mohammed Shoaib

Michael Alan Pogue

Igor Serikov

Eric Matthew Hansen

A system and a method for updating an electronic paper display are disclosed. A memory includes a waveform table and a transition matrix including multiple pixels, each representing a pixel of the electronic paper display. A page transition display system is coupled to the memory and identifies waveforms from the waveform table associated with multiple transition matrix pixels by processing multiple transition matrix pixels in parallel. For example, the page transition display system loads multiple transition matrix pixels into a register and accesses the waveform table using the contents of the register. Using the identified waveforms, the page transition display system generates control signals used to modify the electronic paper device.

Driver for page transitions in an electronic paper device

A system for displaying video on electronic paper displays to reduce video playback artifacts comprises an electronic paper display, a video display driver, a video transcoder, a display controller, a memory buffer and a waveforms module. The video display driver receives a re-formatted video stream, which has been processed by the video transcoder, from the memory buffer. The video display driver directs the video transcoder to process the video stream and generate pixel data. The video display driver loads waveforms into the frame buffer and updates display commands repeatedly to activate the display controller until the end of the video playback. The video display driver directs copying video frames sequentially one by one from the memory buffer to the frame buffer in real time during the video playback. The video transcoder receives a video stream for presentation on the electronic paper display and processes the video stream generating pixel data that is provided to the display controller. The present invention also includes a method for displaying video on an electronic paper display.

Video playback on electronic paper displays

A system for updating an electrophoretic display of an electronic paper device (EPD) has a display driving system comprising a display manager, a compositor, a bounding box list producer, a display controller and a memory storing a bounding box list, a transfer matrix buffer, waveforms and subframes. The display driving system receives one or more display requests from one or more input devices and applications. The display driving system transforms the display requests into bounding boxes and transition matrices of pixel values. The display driving system collapses overlapping bounding boxes into non-overlapping bounding boxes. The display driving system generates subframes using the bounding boxes, the transition matrices and waveforms containing voltage information. The subframes are used to drive the electrophoretic display to display an image.

Bounding box based control method for electronic paper devices

A system and a method are disclosed for updating a bi-stable display includes a framebuffer for storing waveforms for each pixel individually. The system includes determining a current state of a pixel of the bi-stable display; determining a desired state of the pixel of the bi-stable display; and updating the pixel by applying a determined control signal to the pixel to drive the pixel from the current state to the final state. Updating each pixel occurs independently of the other pixels of the bi-stable display.

Full framebuffer for electronic paper displays

A system and a method are disclosed for fast pen tracking a low latency display updates on an electronic paper display. Pen input information is received on an electronic paper display that updates at a predetermined display update rate. A line drawing module of the electronic paper display driver determines at least one pixel to activate based on the received pen input information. The at least one pixel is updated independent of the display update rate of the electronic paper display. Active pixel state information is maintained separately for each pixel in real time until the pixel update is complete and the pixel is deactivated. In some embodiments, a future pixel to activate is determined based on the received pen input information. The future pixel is deactivated if pen input information is not received on the activated pixel for a predetermined amount of time.

Pen tracking and low latency display updates on electronic paper displays

A system and a method are disclosed for updating an image on a bi-stable display includes a module for determining a final optical state, estimating a current optical state and determining a sequence of control signals to produce a visual transition effect while driving the display from the current optical state toward a final optical state. The system also includes a control module for generating a control signal for driving the bi-stable display from the current optical state to the final optical state.

Independent pixel waveforms for updating electronic paper displays

A method and apparatus for finite impulse response (FIR) filter bank architecture and method that involve low-complexity computation resources are described. In one embodiment, a digital image processing system includes an index mapping module to determine a rotation angle index to control rotation of an input patch of an image based on the (x,y) pixel coordinates of the image patch. The digital image processing system may also include a rotation module to rotate the input patch of the image based on the rotation angle index. In one embodiment, the digital image processing system may further include a filter engine module applied to a rotated version of the input patch of the image.

Method and apparatus for FIR filtering using space-varying rotation

Electronic Paper Displays can suffer from 'ghosting' or previous images remaining partially visible after the display has updated to show a new image. A pseudo-random noise intermediate image is used to make the ghosting less visible to human observers. Further, other intermediate images can be used to convey visible information or to convey secret information, e.g. a watermark. A control signal for driving the bi-stable display from the current optical state to an intermediate state, then to a final optical state is also determined. In some embodiments, the intermediate state for each pixel is determined in a pseudo-random manner. The pseudo-random noise values are applied to the bi-stable display to remove noise and other artifacts from the end resulting images. The determined control signal is applied to the bi-stable display to drive the bi-stable to the intermediate state, then to the final optical state.

Spatially masked update for electronic paper displays

A weighted sum of a set of component filters is used to effectively apply different 'composite' FIR filters to compensate for aberrations resulting from different opto-mechanical settings. The FIR filters are 'composite' in the sense that they are a weighted sum of the set of component filters. In one approach, the aberrations vary as a function of the opto-mechanical setting, and the opto-mechanical setting is used to determine the weights of the different component filters.

Imaging system with variable opto-mechanical system, aberrated optics and compensating filter bank

A system for displaying video on electronic paper displays to reduce video playback artifacts that includes an electronic paper display, a video transcoder, a display controller and a waveforms module is disclosed. The video transcoder receives a video stream including pixel data for presentation on the electronic paper display. The video transcoder processes the video stream and generates pixel data that is provided to the display controller by processing a desired value for a pixel of video data and a future value for the pixel of video data. The video transcoder adapts and re-encodes the video stream for better display on the electronic paper display.

A spatially-varying sharpening filter and a color registration module compensate for significant lateral color in poorly corrected optics. In one aspect, a color imaging system includes image-forming optics, a sensor array and a processing module. The processing module includes a color registration module and a spatially-varying sharpening filter. The image-forming optics suffers from lateral chromatic aberration. The sensor array captures color pixels of the chromatically aberrated optical image. The spatially-varying sharpening filter sharpens the image (e.g., reduces the blurring caused by lateral color), and the color registration module realigns different color channels of the image.

Electo-optical color imaging systems having strong lateral chromatic aberration compensated by digital image processing

A method and apparatus for reducing image artifacts on displays (e.g., electronic paper, etc.) are described. In one embodiment, the method comprises generating pixels of an image for a bistable display using halftoning based on data of one or more previously displayed images.

Method for reducing image artifacts on electronic paper displays

A method and system for high-speed and low-complexity geometric transformation of signals are described. In one embodiment, the system comprises an input patch consisting of a window of pixels from an input image. The system may further comprise a transformation selector to generate control data to control a geometric transformation mapping based on the location of a current pixel being processed. In one embodiment, the system may also comprise a hardware geometric transform engine to perform a geometric transformation mapping by switching on one path through the geometric transform engine from an input window to an output pixel using the control data. In one embodiment, the system may further comprise an interpolator to generate interpolated geometric transformation mappings using the control data and multiple outputs from the geometric transform engine by switching on multiple paths from an input window.

Method and apparatus for high-speed and low-complexity piecewise geometric transformation of signals

A class of imaging systems in which the imaging optics, the sensor array and the image processing are related by three parameters: Wthe amount of third order spherical aberration, U the undersampling factor defined as the ratio of the Nyquist frequency of the sensor array divided by the diffraction-limited frequency of the imaging optics, and N the number of rows in the FIR implementation of the image processing. In one aspect, Wis between approximately 2 and 8 waves, U is between approximately 0.05 and 0.30, and N satisfies an equation that defines the acceptable range of N as a function solely of Wand U.

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Mountain View, CA, United States of America

Guotong Feng