Abstract: An omnidirectional remote control for use with electrically controllable devices. The remote control comprises a keypad input and a program selector for determining control signals to be transmitted by circuitry within the remote control. The remote control further comprises control circuitry which may be used to drive a plurality of transmitting diodes that are spaced around the perimeter of the remote control. The transmitting diodes are spaced so as to provide essentially omnidirectional transmission of control signals.

Abstract: A still picture video telephone transmission system for transmitting and receiving, via a telephone line, a still picture taken by a camera; a picture signal is transmitted and received by a transmitting circuit and a receiving circuit, to which improvements are made so as to display a still picture clearly without distortion. For this purpose, the transmitting circuit sends picture element signals together with image correcting signals such as a picture element displacement detecting signal, a phase inversion detecting signal, and settling data. The receiving circuit detects the image correcting signals in the picture element signal, and makes the necessary corrections so as to enable the still picture to be displayed in good shape.

Abstract: An improved video phone which transmits a source image over a standard telephone line in conjunction with audio voice signals is disclosed. The unique initialization protocol allows asynchronous transmission with its short format. The protocol format provides for a hardware preamble for synchronizing a receiver clock, a software preamble for identifying the video image and disabling the audio, automatic gain control adjustment data and amplitude calibration data. The audio portion is disabled by coupling a capacitor across the telephone to effectively short the telephone. The telephone is placed across the bridge circuit which is provided with switches to balance the bridge in both the telephone audio and the video modes. The transmitted as well as the received signal are passed through the same delay equalization circuit, so that half the delay equalization is done before transmission, with the remaining half being done after reception.

Abstract: A still picture picturephone communication system for transmitting and receiving a still picture over a telephone circuit including a handshaking process wherein prior to still picture transmission, identification code data indicating a function of the picturephone set is transmitted and received, and a decision is made as to whether the still picture is being transmitted or not. A designation code of a desired response waiting time within an identification code data used at the time of handshaking is formed, and the response is delayed by a period of time corresponding to the response waiting time. A still picture data is directly transmitted and received without handshaking. In addition character data including character information and the like can be transmitted and received, and by manipulating the picturephone set of one party the picturephone set of the other party can be made to transmit picture data therefrom. Furthermore, the picture sent from the called party can be transferred to a third party.

Abstract: An improved video phone transmits a source image over a standard telephone line in conjunction with voice signals. The unique initialization protocol provides a hardware preamble for synchronizing a receiver clock, a software preamble for identifying the video image and disabling the audio, automatic gain control adjustment data and amplitude calibration data. The audio portion is disabled by coupling a capacitor across the telephone to effectively short the telephone. The telephone is placed across a bridge circuit which is provided with switches to balance the bridge in both the telephone and video modes. The transmitted and received signals pass through the same delay equalization circuit, so that half the equalization is done before transmission, with the remaining half being done after reception. Input and output selectors allow the same circuit to be used. The digital signals are level shifted up prior to being converted into analog, and then are shifted down again to reduce the effects of DC offset.

Abstract: The present invention provides a QAM modulation scheme compatible with a single channel demodulator. The inphase (I) channel is provided with luminance information encoded on a series of sine wave symbols. The quadrature (Q) channel is used for color difference values with a sine or cosine symbol being used for each color difference value. Alternate ones of these color difference symbols are inverted so that, on the average, their effect on the I channel zero-crossings simply cancels out. Thus, when sent to a single channel demodulator which expects a black and white picture, the quadrature channel will be filtered out; leaving luminance information which will be decoded as a black and white picture. The color information does not disturb the zero crossings of the luminance signal on an averaged basis, allowing the carrier recovery phase lock loop to maintain synchronization for demodulation purposes.

Abstract: The present invention assigns amplitudes of sine wave cycles in a data packet on I and Q channels of a QAM signal to color, gray or luminance values. Overlapping sine wave cycles on the I and Q channels in the data packet are assigned to the same or neighboring pixels. A synchronizing signal is sent at the beginning of each transmission of a packet. The synchronizing signal is a plurality of cycles at a maximum amplitude on the I and Q channels. The synchronizing signal serves two functions simultaneously. First, it is used to indicate the beginning of a new packet. Second, the phase of the synchronizing signal is used to initialize the demodulator phase detecting circuitry.

Abstract: The present invention is a conversational freeze-frame video phone which transmits a source image over a standard telephone line in conjunction with audio voice signals. A camera is used to capture an image to be transmitted and the image is mapped onto an image field of 2,000 to 5,000 pixels. The image field is displayed on a display area of approximately one square inch on a display screen. Digitized data representing the pixels is asynchronously transmitted on a modulated signal in a single burst of less than three seconds duration. Corresponding remote images are asynchronously received, demodulated, and displayed. The transmission of the audio signal is interrupted upon the detection of a video image being transmitted.

Abstract: In a word processing system that includes a printer for printing text material and a display screen for viewing portions of the display material, a graphical representation of a page of text is displayed for editing purposes, the graphical representation including a plurality of identically formed display elements each corresponding to one of the characters of the text.