Abstract: A photoelectric conversion apparatus includes a plurality of pixels including a photodiode configured to perform avalanche multiplication, and a signal processing circuit configured to generate a signal. The signal processing circuit includes a control circuit, a counter, and an illuminance determination circuit. The control circuit is connected to the photodiode and a generation circuit configured to generate a pulse signal, and controls a state between a first state, and a second state, in accordance with the pulse signal. The counter counts the number of periods in which avalanche multiplication occurs, among a plurality of periods in the first state. The illuminance determination circuit determines whether a count value of the counter has reached a threshold value. The signal processing circuit includes a circuit configured to set a frequency of the pulse signal in accordance with a result of determination performed by the illuminance determination circuit.

Abstract: A photoelectric conversion apparatus includes a first pixel and a second pixel, each of which includes a photodiode, and a signal processing circuit including a control circuit and a counter. The control circuit is connected to the photodiode and a circuit configured to generate a pulse signal, and performs control, based on the pulse signal, so as to be in a standby state or a recharge state. The counter counts the number of periods in which avalanche multiplication has occurred in the standby state. A third pulse of the pulse signal for the second pixel is input to the control circuit in a period from when a first pulse of the pulse signal for the first pixel is input to the control circuit to when a second pulse of the pulse signal for the first pixel subsequent to the first pulse is input to the control circuit.

Abstract: A photoelectric conversion apparatus includes a plurality of pixels including a photodiode configured to perform avalanche multiplication, and a signal processing circuit configured to generate a signal. The signal processing circuit includes a control circuit, a counter, and an illuminance determination circuit. The control circuit is connected to the photodiode and a generation circuit configured to generate a pulse signal, and controls a state between a first state, and a second state, in accordance with the pulse signal. The counter counts the number of periods in which avalanche multiplication occurs, among a plurality of periods in the first state. The illuminance determination circuit determines whether a count value of the counter has reached a threshold value. The signal processing circuit includes a circuit configured to set a frequency of the pulse signal in accordance with a result of determination performed by the illuminance determination circuit.

Abstract: In a case where illuminance is high, an error between the number of photons per frame calculated from time information and the number of photons and the actually expected number of photons per frame is reduced. In a time counter that counts a clock from the start of exposure in one frame, one-count time in the clock is switched depending on the illuminance. In a case where a pixel counter is saturated within a period of one frame, the illuminance is determined to be high, and a high-illuminance clock in which one-count time is set more minutely in the first half of one frame is used to count. In a case where the illuminance is not determined to be high, a normal clock is used to count.

Abstract: With this invention, color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing generation of moiré due to the color shifting correction, and forming a high-quality image. To this end, an image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts with respect to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units C, M, Y, and K calculate color shifting correction amounts for respective color components on the basis of the stored color shifting amounts.

Abstract: With this invention, color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing generation of moiré due to the color shifting correction, and forming a high-quality image. To this end, an image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts with respect to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units C, M, Y, and K calculate color shifting correction amounts for respective color components on the basis of the stored color shifting amounts.

Abstract: Color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing caused by color shifting correction, and forming a high-quality image. An image forming engine has color shifting amount storage units storing actual shifting amounts with respect to ideal scan directions on image carriers in image forming units. Color shifting correction amount arithmetic units calculate color shifting correction amounts for respective color components using stored color shifting amounts. Color shifting correction units perform color shifting correction by converting coordinates upon reading image data from bitmap memories using calculated color shifting correction amounts, and perform tone correction. Data after tone correction undergo halftone processing.

Abstract: An image processing apparatus sets a variable-magnification ratio of image data, discriminates whether or not the set variable-magnification ratio is larger than a predetermined threshold value, and decides a memory size of a memory device for storing the image data in accordance with a discrimination result in the discriminating. The Apparatus stores the image data of an amount corresponding to the decided memory size into the memory device, and executes a variable-magnification process to the image data stored in the memory device by using the set variable-magnification ratio.

Abstract: Color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing caused by color shifting correction, and forming a high-quality image. An image forming engine has color shifting amount storage units storing actual shifting amounts with respect to ideal scan directions on image carriers in image forming units. Color shifting correction amount arithmetic units calculate color shifting correction amounts for respective color components using stored color shifting amounts. Color shifting correction units perform color shifting correction by converting coordinates upon reading image data from bitmap memories using calculated color shifting correction amounts, and perform tone correction. Data after tone correction undergo halftone processing.

Abstract: With this invention, color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing generation of moiré due to the color shifting correction, and forming a high-quality image. To this end, an image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts with respect to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units C, M, Y, and K calculate color shifting correction amounts for respective color components on the basis of the stored color shifting amounts.

Abstract: An image processing apparatus sets a variable-magnification ratio of image data, discriminates whether or not the set variable-magnification ratio is larger than a predetermined threshold value, and decides a memory size of a memory device for storing the image data in accordance with a discrimination result in the discriminating. The Apparatus stores the image data of an amount corresponding to the decided memory size into the memory device, and executes a variable-magnification process to the image data stored in the memory device by using the set variable-magnification ratio.

Abstract: An image forming apparatus includes a device-information storage unit configured to store a scanning frequency of an oscillating device; an image storage unit configured to store image data used for image formation; an image processing unit configured to perform an enlargement or reduction, in a direction orthogonal to a direction of the scanning of the laser beam and in accordance with a given parameter, on the image data stored in the image storage unit; a setting unit configured to calculate the parameter from the scanning frequency stored in the device-information storage unit and a predetermined reference frequency and configured to provide the parameter to the image processing unit; and a driving unit configured to drive a laser beam device according to the image data processed by the image processing unit.

Abstract: A color image forming apparatus of a so-called tandem type which has image forming units in correspondence with colors is provided. In the color image forming apparatus, a color discrepancy amount storage unit stores information of a color discrepancy amount of each of the image forming units, which is measured in advance. A first color discrepancy correcting unit performs color discrepancy correction in a pixel unit by performing coordinate conversion of bitmap data to be printed based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit. A second color discrepancy correcting unit performs color discrepancy correction in less than a pixel unit by performing tone correction of the bitmap data corrected by the first color discrepancy correcting unit based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit.

Abstract: With this invention, color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing generation of moiré due to the color shifting correction, and forming a high-quality image. To this end, an image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts with respect to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units C, M, Y, and K calculate color shifting correction amounts for respective color components on the basis of the stored color shifting amounts.

Abstract: A shifting amount of color compensation amount is calculated based on a shifting amount of color obtained from a shifting amount of color storage unit for each image forming unit, and shifting amount of color compensation in the pixel unit is performed by executing address conversion using the calculation result. A feature of an image to be processed is detected, and color density conversion compensation for performing shifting amount of color compensation in less than the pixel unit is performed according to the detected feature. Furthermore, half-tone processing or exceptional processing is selectively executed according to the detected feature.

Abstract: A color image forming apparatus of a so-called tandem type which has image forming units in correspondence with colors is provided. In the color image forming apparatus, a color discrepancy amount storage unit stores information of a color discrepancy amount of each of the image forming units, which is measured in advance. A first color discrepancy correcting unit performs color discrepancy correction in a pixel unit by performing coordinate conversion of bitmap data to be printed based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit. A second color discrepancy correcting unit performs color discrepancy correction in less than a pixel unit by performing tone correction of the bitmap data corrected by the first color discrepancy correcting unit based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit.

Abstract: An image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts relative to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units calculate color shifting correction amounts for respective color components to base on the stored color shifting amounts. Color shifting correction units C, M, Y, and K perform color shifting correction by converting coordinates upon reading out image data from bitmap memories C, M, Y, and K on the basis of the calculated color shifting correction amounts, and then perform tone correction. Data after tone correction undergo halftone processing by halftone processors. C, M, Y, and K to suppress moire. PWM processors C, M, Y, and K generate PWM signals for scanning, and output them to exposure units C, M, Y, and K of the respective image forming units.

Abstract: A color image forming apparatus of a so-called tandem type which has image forming units in correspondence with colors is provided. In the color image forming apparatus, a color discrepancy amount storage unit stores information of a color discrepancy amount of each of the image forming units, which is measured in advance. A first color discrepancy correcting unit performs color discrepancy correction in a pixel unit by performing coordinate conversion of bitmap data to be printed based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit. A second color discrepancy correcting unit performs color discrepancy correction in less than a pixel unit by performing tone correction of the bitmap data corrected by the first color discrepancy correcting unit based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit.

Abstract: An image forming system includes an information processing apparatus and an image forming apparatus. The information processing apparatus performs image generation, color conversion, and extraction of image characteristics to generate compressed data. The image forming apparatus decompresses the compressed data and determines a writing address into an image data storing unit on the basis of an amount of shift to convert the density of the image data in fractional pixel units.

Abstract: An image forming apparatus which forms an image by scanning a light beam in a main-scan direction of a photosensitive member, the apparatus including: an output unit which irradiates a light beam for exposing the photosensitive member; a deflection unit which deflects a light beam from the output unit to scan the photosensitive member in the main-scan direction; a light-receiving unit which detects the light beam deflected by the deflection unit; a computation unit which calculates difference information by using information of a detected time; a control unit which drives the deflection unit by setting a parameter for controlling operation of the deflection unit; a prediction unit which predicts a correction amount of a scan width in the main-scan direction in a next scan; a modulation unit which generates a driving signal for driving the output unit; and a driving unit which drives the output unit.