83 results about "Video-signal generator" patented technology

An apparatus and method provide non-intrusive in-service testing of audio/video synchronization testing without using traditional audio marker tones. The network includes an A/V synchronous test signal generator which injects video and audio markers into the video and audio non-intrusively and routes the two signals into a switch where they are switched into a channel for encoding and transmission via the ATM network. At the distant end the signal is decoded and routed by a switch into the A/V test generator and measurement set where the markers are detected and the A/V skew calculated, after which the audio and video are routed to the subscriber. The A/V test set signal generator includes a Video Blanking Interval (VBI) test signal generator and a white noise generator, the former injecting a marker into the video signal and the later injecting an audio marker into the audio signal. The video marker is injected into the VBI and broadband, background audio noise to measure the delay between the audio and video components of a broadcast. The marking of the audio is accomplished by gradually injecting white noise into the audio channel until the noise level is 6 dB above the noise floor of the audio receiver. As a precursor A/V sync signal, a small spectrum of the white noise is notched or removed. This signature precludes inadvertent recognition of program audio noise as the audio marker.

Provided are a cheap display device and a display method that are capable of preventing loss of high-frequency component during generation of a video signal from a source signal while at the same time securing continuity of pixel data.

The display device includes a display portion 7 capable of displaying distinct videos on a common screen in a plurality of viewing directions and a video signal generating portion 300 for generating video signals by carrying out compression processing of video source signals for the viewing directions at predetermined compression rates. The video signal generating portion 300 generates new color components by using color components of a plurality of adjacent pixels aligned in a predetermined direction among pixels corresponding to the video source signals, and generates each of the video signals on the basis of a new pixel composed of the generated color components.

A signal simulation device for testing and developing radio receivers adapted to orientate antenna beams to different radio transmitters and to simultaneously suppress interference signals, comprises an antenna array, a signal generator generating reproducible digital signals in the complex baseband, and a digital matrix processor combined and synchronized with the signal generator. The processor has input signals generated by the signal generator and has output signals that form received signals of the antenna array. The input signals of the matrix processor are phase shifted according to a direction of incidence and to relative positions of the elements within the antenna array of the radio receiver, and are combined and supplied to outputs of the matrix processor. Amplitude and phase shift are simulated by weighting of the input signals from the signal generator, the weighting coefficients being calculated on a control computer and input into the matrix processor via an interface.

A multi-phase signal generators and methods for generating multi-phase signals are described. In one embodiment, a clock generator generates quadrature signals including those having 90, 180, 270 and 360 degrees phase difference with a first signal. The rising edge of an intermediate signal is compared with the rising edges of two of the other signals to generate an UP and DN pulse signal, respectively. The UP and DN signals are used to adjust the delay of a delay line producing the signals to synchronize the signals. In some embodiments, a reset signal generator is used to truncate the UP or DN signal pulse.

The invention relates to a projection screen and a projection system, wherein, the projection screen comprises a curtain, a shell, a scroll and a sound system; an accepting trough with openings are formed on the shell, the scroll is pivoted in the accepting trough of the shell for rolling the curtain, and the sound system is arranged on the shell. The projection system comprises the projection screen, an audio and video signal generator and a projector, wherein, the audio and video signal generator is respectively connected with the projector and the sound system and sends audio signals to the sound system and video signals to the projector, the projector is used for converting received video signals to images to be projected on the projection screen. In the invention, by installing the sound system on the shell, the projection images can be displayed on the screen and the sound can be played simultaneously, therefore, the projection screen has the beneficial effect of playing pictures, sound and images simultaneously.

The invention provides a video delay testing device in a monitoring system. The device comprises a video signal generator, a video delay analysis unit and a synchronization link, wherein the video signal generator is used for generating a continuously changing time varying video signal and a timestamp of each frame of image and packaging and transmitting image mode information and time information to the delay analysis unit; the video delay analysis unit is used for identifying a frame mode of a decoded video to determine system time generated by the frame mode and subtracting frame mode occurrence time from the system time which is decoded and displayed currently to obtain video transmission delay of the system; and the synchronization link is used for realizing synchronization of the video signal generator and the video delay analysis unit. The device solves a problem of video delay measurement in an actual engineering application, provides the realizable video delay measurement device and method for related professional institutes and construction units, fills a blank of the measurement field and improves the technological level of the national security and protection system, especially the monitoring system.

A broadcast receiver includes a first video signal selector which outputs a video signal of a main-picture; a second video signal selector which outputs a video signal of a sub-picture; a first audio signal selector which outputs an audio signal of the main-picture; a second audio signal selector which outputs an audio signal of the sub-picture; a first video processor which generates a third video signal from the video signals of the main-picture and/or sub-picture; a feature quantity generator which generates a feature quantity of the audio signal of the sub-picture in accordance with a result of comparison between data corresponding to the audio signal of the sub-picture and sound class model data created beforehand; a determination processor which determines a scene as a specified scene; and a controller which controls the whole components in accordance with the specified scene.

The invention discloses an autosynchronous multichannel parallel storage DDS (direct digital synthesis) signal generator. A data clock phase judgment module is added and used for synchronous detection on a data clock obtained after a sampling clock is subjected to m frequency division by each channel DAC, namely, the DAC internal frequency divider of the k path; if certain path (channel) is asynchronous with a reference data clock, the DAC internal frequency divider of the path (channel) is reconfigured and redetected until all channels are synchronous. According to the invention, the data clock phase judgment module is used for synchronous detection of data pulse of all channels and reconfiguring the DAC internal frequency dividers of the asynchronous channels until the channels are synchronous, so that auto synchronization of wave signals output by all channels is realized.

An endoscope system comprises a light source, a light sensor, a signal processor, a video-signal generator, and a switcher. The light source emits red light including a first wavelength, green light including a second wavelength, and blue light including a third wavelength. The light sensor receives the light of the light source. The signal processor obtains a red signal based on the red light, a green signal based on the green light, and a blue signal based on the blue light. The video-signal generator generates video signal based on the red, green, and blue signals. The switcher switches between a first switching state and a second switching state. The red, green, and blue signals are output to the video-signal generator in the first switching state. The green and blue signals are output to the video-signal generator in the second switching state.

Method and apparatus for generating a composite audio signal clocked to a selected frequency from left and audio input signals. A video/audio signal generator transmits the left and right audio input signals, together with a video signal having a horizontal synchronization signal embedded therein. If copy protection has not been applied to the video signal, the embedded horizontal synchronization signal will have a frequency of 15.734 KHz. If applied to the video signal, copy protection techniques will shift the frequency of the horizontal synchronization signal. To avoid distortion of the composite audio signal, a switch configured to selectively couple the video signal or a secondary video signal generated by an internal video signal generator to an audio signal processor which generates the composite audio output signal from the left and right audio input signals. Embedded within the secondary video signal is a horizontal synchronization signal having a frequency of 15.734 KHz. Thus, if copy protection features cause the frequency of the signal embedded within the primary video signal to shift, the switch may be used to couple the audio signal processor to the internal video signal generator, thereby ensuring that the composite audio signal will always be clocked to the selected frequency.

A display apparatus includes: a display panel that includes display elements having a current-driven light-emitting portion, in which the display elements are arranged in a two-dimensional matrix in a first direction and a second direction, and that displays an image on the basis of a video signal; and a luminance correcting unit that corrects the luminance of the display elements when displaying an image on the display panel by correcting a gradation value of an input signal and outputting the corrected input signal as the video signal. The luminance correcting unit includes a reference operating time calculator, an accumulated reference operating time storage, a reference curve storage, a gradation correction value holder, and a video signal generator.

Provided are a display apparatus and a display apparatus driving method. The display apparatus includes: a display panel that includes display elements having a current-driven light-emitting portion, in which the display elements are arranged in a two-dimensional matrix in a first direction and a second direction, and that displays an image on the basis of a video signal; and a luminance correcting unit that corrects the luminance of the display elements when displaying an image on the display panel by correcting a gradation value of an input signal and outputting the corrected input signal as the video signal. The luminance correcting unit includes a reference operating time calculator, an accumulated reference operating time storage, a reference curve storage, a gradation correction value holder, and a video signal generator.

The invention discloses a digital display scope (DDS) signal generator and an amplitude control method of the digital display scope (DDS) signal generator. The DDS signal generator comprises a main control unit, a field programmable gata array (FPGA) module connected with the main control unit and a composite DAC connected with the FPGA module, wherein the main control unit is used for allocating amplitude compensation coefficients and reference voltage values so as to enable a sum of a bit wide of the amplitude compensation coefficients and the bit wide of the reference voltage values to be bigger than or equal to the bit wide of wave form sampling points. The FPGA module comprises a wave form storage used for storing wave form sampling points, a digital multiplier used for multiplying the wave form sampling points by the amplitude compensation coefficients to obtain a wave form digital quantity and sending the wave form digital quantity to a data DAC installed inside the composite DAC and a signal program initiation (SPI) control module is used for converting the reference voltage values into an SPI form and sending to a gain DAC installed inside the composite DAC, and the composite DAC converts wave form figures in the data DAC into an analogy quantity according to the reference voltage values in the gain DAC.

An onboard vehicle entertainment system is for use within a passenger compartment of a vehicle. The system includes an audio/video signal generator including an onboard wireless transmitter configured for placement within the passenger compartment of the vehicle to produce a vehicle-specific audio/video signal with an audio signal and a video signal component. An audio receiver also forms part of the system and is configured for placement within the passenger compartment of the vehicle, the is adapted for wireless receipt and presentation of the audio signal component transmitted by the onboard transmitter. The system also includes a video receiver configured for placement within the passenger compartment of the vehicle, and the video receiver is adapted for wireless receipt and display of the video signal component transmitted by the onboard transmitter.

A display apparatus includes a video signal converter unit which converts input video signals of n colors (n is an integer equal to or larger than 2) into converted video signals of at least (n+1) colors, a video signal generator unit which, on the basis of the input video signal of at least one color, generates converted video signals of new (n+1) colors with the luminance of two or more converted video signals being improved, a display panel which displays (n+1) images sequentially on the basis of the converted video signals of the new (n+1) colors, and a backlight which switches between light sources of (n+1) colors for illumination sequentially in accordance with the images displayed on the display panel.

The invention discloses a frequency characteristic testing system based on a virtual instrument. The frequency characteristic testing system comprises a master computer and a slave computer, wherein the slave computer comprises a DDS (digital display scope) signal generator, an I/Q demodulator, a programmed gain amplifier, an AD (analogue-digital) converter and a single chip microcomputer; the master computer and the single chip microcomputer are subjected to two-way communication; the DDS signal generator generates two paths of orthogonal signals by program control of the single chip microcomputer; an Asin signal output end is connected into a tested circuit; signal stimulation is provided for the tested circuit; a signal output end of the tested circuit is connected with an input end of the I/Q demodulator; an Acos signal output end is connected with another input end of the I/Q demodulator; two input signals are subjected to down-conversion by the I/Q demodulator, so as to obtain two paths of direct current signals; the two paths of direct current signals are connected into the AD converter to be subjected to analogue-digital conversion after being amplified by the programmed gain amplifier of which the gain is set by the single chip microcomputer; the signal subjected to analogue-digital conversion is output to the master computer after being processed by the single chip microcomputer; the master computer achieves data calculation, analysis and display through Matlab software.

A display apparatus includes: a display panel that includes display elements having a current-driven light-emitting portion, in which the display elements are arranged in a two-dimensional matrix in a first direction and a second direction, and that displays an image on the basis of a video signal; and a luminance correcting unit that corrects the luminance of the display elements when displaying an image on the display panel by correcting a gradation value of an input signal and outputting the corrected input signal as the video signal. The luminance correcting unit includes a reference operating time calculator, an accumulated reference operating time storage, a reference curve storage, a black-level shift amount holder, and a video signal generator.

The invention relates to a method for realizing a GMSK (Guassian Minimum Shift Keying) signal generator based on an FPGA (Field Programmable Gate Array), which comprises the following steps: integrating an NRZ (Non-Return-to-Zero) coding module, a Gaussian filter module, a phase accumulation module, an orthogonal modulation module and a D/A (Digital to Analog) conversion module on an FPGA chip, filtering through NRZ coding and filtering mode selecting, accumulating a filtered signal into a phase value, carrying out two paths of ROM (Read Only Memory) table look-up on the phase value, multiplying a cosine value of one of the two paths by a coswt signal, multiplying a sine value of the other path by a sinwt signal and taking a difference between products of the two paths of signals as a generated GMSK modulation signal. The method has the beneficial effects that the signal modulated by the GMSK signal generator, which is realized by adopting the method, can select a filter with different filtering modes through flexibly controlling the switching of the filtering modes according to the filtering requirements of a system to realize the generation of a GMSK signal with different system bandwidth demands; and moreover, the method has the characteristics of high realization speed and less resources occupied, thereby satisfying the demand that the digital information processing system realizes the full digitalization of the GMSK signal generator.