The Design And Implementation Of Audio And Video Signal Generator Based On DMP

Audio and video measurement system is a system designed to ensure the quality of the audio and video information and its transmission system through the measurement of a variety of audio and video devices, equipment and transmission lines to test the working state. The basic measurement method is putting a standard video test signals into the video channel front-end, and test the distortion of the signal and the changes of the parameters in the end of the channel, which determine the performance and quality of the channel of transmission.This paper puts forward a design of an audio and video signal generator, and describes the implementation in detail. The design use the HDD Player based on RTD1073 of RealTek company as the implementation platform. The process is:Use MATLAB on PC to generate BMP file as standard video test signals; use Adobe Audition software to generate WAV file as audio test signals. Then store these files into the player and play them, its analog audio and video interface output standard test signals. As the player has hardware system errors and cause distortion of signals. This paper presents error correction theory and correct the test signal with Tektronix VM700. Test signals have great technical indicators after the calibration.The innovation of this design are:1. Use software and hardware combination to make the audio and video signal generator produce any number of high-quality test signals, the software allows the signal generator to achieve flexibility and scalability, and overcome the difficulties and high cost disadvantage of the past measuring equipment which implemented by hardware.2,light and small size, and achieve networking remote control functionality, making the measurements convenient.The signal generator in this paper works well in actual measurement and achieves the desired objectives. The signal generator can generate 30 kinds of subjective and objective common video test signals, and audio test signals within the range of 20Hz～20kHz. The technical indicator of the signal generator meets the Grade A specifications of GY/T 152-2000 "Operation and Maintenance Regulations of TV Center Production System", and is similar to the Tektronix signal generator TSG95 and ASG100.