Abstract: A digital copier has a memory for storage of image data, reads image data and stores the image data in the memory, and prints an image depending on the image data stored in the memory. The digital copier can also register a plurality of jobs. Based on a registered job an image is printed. Then, based on the subsequent job an image is printed. When an image data corresponding to a new job cannot be stored in the memory, the digital copier effects the process for calculation of job execution time, a process of calculating a free memory capacity, and a process of calculating the time required for obtaining a timing at which a free memory space is provided, to display the time at which the image data corresponding to the new job can be stored. Thus, a digital copier can be provided allowing the user to form images efficiently.

Abstract: A digital copier has a memory for storage of image data, reads image data and stores the image data in the memory, and prints an image depending on the image data stored in the memory. The digital copier can also register a plurality of jobs. Based on a registered job an image is printed. Then, based on the subsequent job an image is printed. When an image data corresponding to a new job cannot be stored in the memory, the digital copier effects the process for calculation of job execution time, a process of calculating a free memory capacity, and a process of calculating the time required for obtaining a timing at which a free memory space is provided, to display the time at which the image data corresponding to the new job can be stored. Thus, a digital copier can be provided allowing the user to form images efficiently.

Abstract: In an image processing apparatus, an image reading unit reads a document put on a platen glass to generate image data, and a detector in the image reading unit detects offset, tilt angle and document area of the document put on the platen glass. A rotation angle is set based on the image data of a document. The entire document area is determined based on a portion of the document which exists within the image reading area when the document extends beyond the image reading area. The document area can be detected even if a document is not rectangular. For example, a slope of the document is determined based on the detected longest segment. In order to solve the unequal reading pitch, the longest segment is selected in the segments having a slope smaller than a predetermined angle relative to the subscan direction. Then, the image data are corrected according to the above result.

Abstract: A compression/expansion apparatus has a plurality of compression/expansion processors for compressing or expanding image data. They are connected in parallel, and a data transfer controller controls data transfer with the plurality of compression/expansion processors. A setter sets each of the plurality of compression/expansion processors for compression or expansion according to input data transferred under the control by the data transfer controller. The number of compression/expansion processors used for compression and that used for expansion are changed according to a mode in order to improve efficiency of the processors.

Abstract: An image data coding device and the like capable of improving the compression ratio of entropy coding of color image data is disclosed. The image data coding device converts input color image data into color image data whose color is expressed by color data and brightness data each represented by multiple bits. Setting a value of color data that corresponds to an achromatic color at 00h as one example, the image data coding device converts the color data of the color image data into color data whose values are assigned in such a manner that the differences between these values and the value of the achromatic color data become larger as the distances away from the value of the achromatic color become larger. The image data coding device then performs entropy coding on the color image data.

Abstract: The present invention discloses a coder and a coding method that raise the possibility of improving the compression ratio of multivalued image data in which one pixel consists of a plurality of bits and are accordingly effective to increase the amount of image that is stored in a recording medium with a certain capacity. The coder according to the present invention includes an obtaining unit for obtaining a predetermined amount of image data in which one pixel consists of a plurality of bits, a developing unit for developing on the virtual plane each piece of the bit data in the obtained image data, and a coding unit for performing the entropy coding on the developed bit data.

Abstract: In an image processing apparatus, an image reading unit reads a document put on a platen glass to generate image data, and a detector in the image reading unit detects a tilt angle of the document put on the platen glass. A rotation angle is set based on the image data of a document and the image data is modified according to the rotation angle. The modification is controlled so as not to deteriorate the image quality. For example, the image data is rotated by an angle at which the document is tilted when the document is read, if the detected tilt angle of a document is larger than a predetermined value. The modification of the image data may be controlled according to a characteristic of the image data. For example, the image data is not rotated when the document is decided to include a half-tone image by detecting the attribute of the image data.

Abstract: An image processing apparatus capable of outputting high quality image by correcting deviations of respective positions or inclinations of a plurality of sheets of document simultaneously placed on a document base and an image forming apparatus connected to the image processing apparatus and capable of forming a copy with no inclination in respect of paper. Image data with the corrected position or corrected inclination is provided by processing the image signal.

Abstract: A digital copy machine with a memory feature can have a plurality of jobs registered in a memory to execute the registered jobs in order. When the content of a job already registered in the memory is corrected, the time required for the job prior to correction and after correction is calculated. When the required time of the job is prolonged by the correction, execution of that job is deferred for a later execution. Thus, unexpected delay in processing another job can be prevented.

Abstract: In transmission of a serial digital data, a serial digital data and inverted data thereof are generated first. Then, one of the serial digital data, and an inverted data of the one of the serial digital data are transmitted successively after the one of the serial digital data according to clock signals. Thus, a pair of the one of the serial digital data and the inverted data is transmitted through a transmission line in the order of the serial digital data. Among the received signals, a first data is sampled at a leading or trailing edge of the clock signal, while a second data is sampled at a trailing or leading edge of the clock signal just after the leading or trailing edge. Then, the first data is stored as a data in a serial data only if the second data is an inverted logical data of the first data. Thus, the serial data are transmitted and latched correctly without interrupting serial transmission even when the received signals include noises.

Abstract: An image forming apparatus records an image on a recording medium after correcting a slant of the image according to a type of document sheet or an operating history of the image forming apparatus. Normally, a slant of the document sheet is corrected by bringing one edge of the sheet in contact with a document scale provided on a document platform. When the sheet is of thin paper or sheets of different sizes are mixed, an image signal obtained by scanning a document image is electrically processed so as to correct a slant of an image to be recorded. When the image signal is electrically processed so as to correct the slant of the image to be recorded, the correction of image slant may be based also on the operating history of the image forming apparatus, for example, the total number of sheets transported, the number of times a paper jam has occurred or the cumulative value of the slant angle of the image.

Abstract: An image forming apparatus records an image on a recording medium after correcting a slant of the image according to a type of document sheet or an operating history of the image forming apparatus. Normally, a slant of the document sheet is corrected by bringing one edge of the sheet in contact with a document scale provided on a document platform. When the sheet is of thin paper or sheets of different sizes are mixed, an image signal obtained by scanning a document image is electrically processed so as to correct a slant of an image to be recorded. When the image signal is electrically processed so as to correct the slant of the image to be recorded, the correction of image slant may be based also on the operating history of the image forming apparatus, for example, the total number of sheets transported, the number of times a paper jam has occurred or the cumulative value of the slant angle of the image.

Abstract: In an apparatus having a main control section and sub-control sections connected to the control section through communication lines for executing desired operations by means of mutual intercommunication with the control section through the communication lines, first and second tri-state buffers are provided between the communication lines and the main control section and between the communication lines and the sub-control section respectively. The tri-state buffers short the communications lines by respective test signals output from the main control sections. When the test signal is not retransmitted to the control section through the communication lines shorted by the second tri-state buffer, anomalous operation of the sub-control section is detected. When the test sinal is not retransmitted to the control section through the communication lines shorted by the first tri-state buffer, anomalous operation of the main control section is detected.

Abstract: An image forming apparatus which includes a replaceable element which is replaced in predetermined amount of use and predicting apparatus for predicting the time when the predetermined amount of use of the element is to be reached. The predicting apparatus predicts the time based on amount of use of the element per unit time and remaining amount of use of the element.

Abstract: A numerical value displaying portion comprising mosaic elements for displaying a three digit numerical value is provided on a displaying portion of an operation panel. The number of copies and the copying magnification rate are switched with each other to be displayed on the numerical value displaying portion. All of the three digits are used to display the copying magnification rate. The lower two digits are used to display the number of copies. When the number of copy is displayed, a color selection mode for the copy images is displayed by utilizing the mosaic elements of the highest digit, which is not used. The light emitting state of the element corresponding to the selected mode is made different from the light emitting state of the elements corresponding to the non-selected mode, so that the displayed mode information can be readily distinguished.

Abstract: When a both-sided binding margin mode is set, data for forming binding margins on two opposing side edges of paper are set. More specifically, a copying magnification based on a size of an original and a size of the copy paper and a count value for determining timing for feeding copy paper are set. Based on those data, an image of a specified magnitude is formed on a photoconductor and this image is transferred, at a transfer position, onto an image area of the copy paper defined by subtraction of a predetermined binding margin width from each of a leading edge and a rear edge of the copy paper. As a result, the copy image is formed with the binding margins being ensured on both edges of the copy paper.

Abstract: An image forming apparatus having an original exposure device for exposing an original in a predetermined exposure area, a specific area designating device for selectively designating a specific area to be edited having a certain size in the exposure area, the specific area including a plurality of sectional blocks, a sectional block designating device for designating at least one desired sectional block from the plurality of blocks, and an image forming device for erasing an image of the original corresponding to the designated sectional block inside the specific area and reproducing the rest of the original image. As each of the designated specific area includes the same number of the sectional blocks, a convenient block size may be obtained by selecting the specific areas having different sizes. Also, it may be conveniently selected whether to copy or erase the original image outside the selected specific area.