摘要:
A system for determining the cumulative position and periodic average velocity of a rotating body having an incremental encoder, operatively connected to the body, for generating a series of periodic signals indicative of rotation of the body. The system also includes a high frequency clock for generating clock pulses at a frequency greater than the maximum frequency of the encoder signal, and a timer for controlling the total time of a predetermined sample interval. Also included in the device is a counter for accumulating the number of integral encoder signal cycles that have been completed, an arithmetic logic unit for determining the size of a fractional portion of an encoder signal cycle that was completed between the last integral encoder cycle and the end of the sample interval. Subsequently, the number of integral encoder signal cycles is added to the fractional portion of an encoder cycle to determine the total number of encoder signal cycles completed, whereby the total is then multiplied by an encoder position conversion factor to determine the cumulative position of the rotating body or belt driven therefrom.
摘要:
When estimating distance to an object in an image using a single camera, data acquired by an onboard accelerometer is analyzed to determine camera speed as the user takes a video of the object of interest. The compression that results during video processing is used to derive motion vectors for the object of interest in the scene. The motion vectors have an opposite direction to the camera motion and a magnitude that is a function of the unknown object distance and a known magnification level. The object distance is calculated from the estimated velocity and motion vector magnitude.
摘要:
Streak compensation in a digital printer is provided utilizing a spatially varying Printer Model and Run Time updates to generate Spatially Varying Tone Reproduction Curves (STRCs) which are used as actuators to compensate for streaks during run time. A full width array sensor is used to measure streak profiles and the STRCs are used as actuators to compensate for streaks. Streak profile measurements taken at a limited number of area coverage levels combined with a Printer Streaks Basis Function Model are used to estimate and project the streak behavior at all area coverage levels and at all inboard-to-outboard spatial locations. The projection is then used in a pixel-wise error feedback control scheme to drive each profile to a desired shape, thereby compensating for streaks.
摘要:
A system determines the noise level of image data by high pass filtering image data. Absolutes values of the high pass filtered image data are determined. Thereafter, multiple mean values for absolute values less than a predetermined number of threshold values are determined. Based upon the determined mean values, a plurality of estimated mean values is calculated, each estimated mean value being calculated from a combination of two determined mean values. The noise of the image is determined from a combination of the minimum estimated mean value and the maximum estimated mean value. This noise can be optionally used by a sigma filter, at Step S740, to sigma filter the image data.
摘要:
A method adapts image data using more than eight bits per pixel to be compatible with devices using only 8-bit per pixel data. The method separates the higher bit depth data into an 8-bit image data stream, the balance of the bits are carried in a separate tag data stream. The 8-bit image data stream can be used in legacy devices that can handle only 8-bit data, and the tag data stream can be used in legacy devices that incorporate a tag data stream for their internal image processing.
摘要:
A first sigma filtering circuit sigma filters an image to produce a filtered image. An analysis circuit processes the sigma filtered image to produce an approximation part and a detail part. A second sigma filter circuit filters the approximation part to produce a sigma filtered approximation part. Another analysis circuit process the sigma filtered approximation part to produce a second approximation part and a second detail part. A third sigma filter circuit sigma filters the second approximation part to produce a sigma filtered second filtered approximation part. A first synthesizer synthesizes the sigma filtered second filtered approximation part and the second detailed part to produce a first reconstructed image, and a second synthesizer synthesizes the first reconstructed image and the first detail part to produce a final filtered image.
摘要:
A method is described to combine two integer lookup tables to realize a single integer lookup table. The method converts each lookup table to a set of floating point values. The conversion process generates a set of floating point values that are as close as possible to the underlying analytic or smooth function that generated the tables in the first place. A system to implement the method is also described.
摘要:
A method is provided for segmenting scanned image data in accordance with mixed raster content processing, further including windowing for purposes of extracting particularly classifiable objects, i.e., text, graphics or pictures. Application of predetermined parameter sets selected for more precise identification of the extracted objects are applied to the data for object extraction, object selection, color uniformity, and clustering for coloring similarity. A page background detection feature uses dual thresholding for segregating text (darker) areas from non-text (brighter) areas. Two histograms are created for the respective areas. Thresholds are generated from the two histograms and applied to the respective areas separately.
摘要:
A method of determining image skew in a scanned document includes scanning the image and determining on a pixel-by-pixel basis whether or not pixels are ON or OFF on scan lines and columns along both the fast and slow scan directions for a particular document rotation angle. Through one read of the image, image data is sampled simultaneously at a plurality of predetermined document rotation angles From the sampled data, the second order moment of the number of ON pixels is calculated as a function of document rotation angle for scan lines along both the fast and slow scan directions, yielding two independent skew angle estimates Skew angle estimates corresponding to valid second order moment data sets are compared and combined to provide a resultant skew angle estimate for the document.