Abstract: A communication apparatus receives the identification information of a partner station, and performs a communication operation in accordance with the received identification information. A first detecting unit detects a calling signal. An identification information receiving unit detects the identification information of a calling party upon detection of the calling signal, and a second detecting unit detects whether or not the terminal of the calling party is a data communication terminal. A registration unit registers the identification information of the partner station in a memory, so that whether the partner station is a speech or data communication terminal can be discriminated later. A control unit checks if the identification information receiving unit receives the identification information of the calling party.

Abstract: A communication system in which when an incoming call has arrived, a communication line having the capability of a high sampling rate is automatically selected without assistance of an exchange operator by transmitting an ultra high speed modem indication signal indicating the capability of data communication at an ultra high speed modem rate among the capabilities of a called terminal, and receiving an ultra high speed modem capability signal indicating the capability of an ultra high speed modem of a calling terminal.

Abstract: A communication system in which when an incoming call has arrived, a communication line having the capability of a high sampling rate is automatically selected without assistance of an exchange operator by transmitting an ultra high speed modem indication signal indicating the capability of data communication at an ultra high speed modem rate among the capabilities of a called terminal, and receiving an ultra high speed modem capability signal indicating the capability of an ultra high speed modem of a calling terminal.

Abstract: A facsimile communication system and a communication apparatus reduce a loss time due to the synchronization of transmission/reception and shorten a communication time. They also shorten a communication time in a full duplex communication mode and allow proper switching of the full duplex communication at the transmission/reception replacement. DIS-CFR signals, EOP-DCN signals, NSS-TSI signals and TSI-DCS signals of a facsimile communication protocol are connected by synchronization signals so that the synchronization signals are sent even after the sending of the protocol signal. Thus, the sending of the synchronization signal for one second when the next protocol signal is sent is not necessary and a time required for the protocol signal is shortened.

Abstract: A communication apparatus receives the identification information of a partner station, and performs a communication operation in accordance with the received identification information. A first detecting unit detects a calling signal. An identification information receiving unit detects the identification information of a calling party upon detection of the calling signal, and a second detecting unit detects whether or not the terminal of the calling party is a data communication terminal. A registration unit registers the identification information of the partner station in a memory, so that whether the partner station is a speech or data communication terminal can be discriminated later. A control unit checks if the identification information receiving unit receives the identification information of the calling party.

Abstract: An image processing apparatus or a facsimile apparatus or the like is constructed by an input unit for inputting image data, a data conversion unit for converting density characteristics of image data inputted by the input unit, and an output unit such as ink jet printer, laser beam printer, or the like for outputting the image data at a predetermined resolution. The data conversion unit converts density characteristics so as to almost equalize densities even when a resolution of the image data that is outputted by the output unit differs. The data conversion unit converts the density characteristics of the input image data on the basis of a luminance/density conversion table formed every resolution of the image data that is outputted by the output unit. The resolution of the output image data is higher than the resolution of the input image data.

Abstract: A communication apparatus includes a communication unit for performing a communication, a speech communication unit for performing a speech communication, a detection unit for detecting the telephone number of the calling side before connection of a call, a registration unit for registering the telephone number of the calling side, and a switching unit for switching a communication mode between the communication unit and the speech communication unit on the basis of the telephone number of the calling side detected by the detection unit, and the telephone number registered in the registration unit.

Abstract: A data communication apparatus includes a data communication section for preforming data communication according to full duplex communication, a testing section for performing a communication test prior to the data communication, and a transmission controller for determining whether full duplex communication can be performed during a period of the communication test performed by the testing section. The testing section includes a backward signal generator, a backward signal detector, and a control signal analyzer. The backward signal generator and the backward signal detector may be replaced with an echo canceller.

Abstract: An image transmission apparatus including a storage unit for storing an image signal; a conversion unit for converting the number of dots of one line image signal in the storage unit; and a transmission unit for selectively transmitting the output of the conversion unit or an image signal in the storage unit.

Abstract: A data transmission apparatus includes; comprising: a transmission data generating unit, a storage unit for storing the transmission data; and a unit for transmitting the transmission data in the storage unit; wherein the storage unit stores, together with the transmission data, time and date when the transmission data was stored.

Abstract: An image transmission method includes the steps of: obtaining an image signal by reading an original image; compression-encoding the obtained image signal; temporarily storing the encoded image data into a temporary storage memory; presuming the empty capacity of a buffer memory for temporarily storing the received image data at a receiving side; and transmitting the encoded image data in accordance with the presumed empty capacity.

Abstract: The invention realizes high speed image transmission in an image processing system such as a facsimile system by reducing redundancy of an image data source for transmission, and improves the error rate of analog transmission systems by combining a synchronizing signal of a plurality of bits with a skip signal of a plurality of bits. The white block skip system can be applied not only to the AM-PM-VSB system but also to the AM-DSB system by discriminating a synchronizing signal, a skip signal, a guard band signal and a picture signal based on only amplitude data and duration data and not on phase data. Errors in received images due to transmission line distortion are eliminated by first transmitting from a transmitter signals of high level for a predetermined number of bits and then signals of zero level, and by checking at a receiver the received signals every predetermined number of bits.

Abstract: The present invention discloses a technique of effecting recording on a recording medium by a plurality of recording elements, wherein recording density by the plurality of recording elements is varied. Further, the recording density by the plurality of recording elements is varied in accordance with a time required for electrical transmission of informations to be recorded for definite numbers of scanning lines. For example, when the time required for such electrical transmission is short, the recording is effected by small numbers of the recording elements, while, when the time required for the electrical transmission is long, the recording operation is effected by large numbers of the recording elements, thereby preventing the image quality from lowering.

Abstract: In the transmission of binary image signals obtained by scanning of an original document, a high signal compression ratio without deterioration in image quality is achieved by subjecting the binary image signals to a selective thinning process in which the signals of a run-length within a determined range are converted into signals of a determined length and by subsequently coding thus selectively thinned signals. A further improved signal compression is also established without deterioration of image quality by conducting, prior to the selective thinning process, preliminary processes such as elimination of isolated dots in the image or smoothing in the principal and auxiliary scanning directions.

Abstract: This invention relates to the reduction in time required for signal transmission in facsimile apparatus, and consists of a transmitting apparatus adapted for eliminating the signal indicating the line thickness from the binary image signal obtained by scanning the original to be transmitted and transmitting thus obtained band-compressed transmission signal, and a receiving apparatus adapted for adding a signal approximately equal to the above-mentioned signal indicating the line thickness to the above-mentioned transmission signal thereby forming received image.