Storage Of Video Signals Research Articles

Adaptive two-step edge-based partial distortion search algorithm using motion vector prediction

Motion estimation is a core process within video coding schemes, because it enables the transmission and storage of video signals, while using a lower bit rate. Various methods have been proposed for motion estimation. A full search algorithm is considered to be the optimal method, but it suffers from a high computational burden. In order to reduce the computations, this paper proposes an adaptive two-step edgebased partial distortion search algorithm. The proposed algorithm reduces computations by reducing the total search point and adjusting the search range. The proposed algorithm is 147 times faster than full search (FS), 12 times faster than normalized partial distortion search, and 1.75 times faster than a two-step edge based partial distortion search (TS-EPDS). It also shows a high video quality, in comparison with FS, in terms of PSNR. The proposed algorithm is suitable for real-time implementation of high-quality digital video applications.

Low-cost acquisition of video images simultaneously with 240 electrophysiological signals

We developed a low-cost system for simultaneous collection and storage of physiological and video signals. The system samples and multiplexes up to 240 low-bandwidth analog channels with a camera video signal, and outputs a standard composite video signal containing analog and video data. The combined signals can be stored on video tape or can be digitized by an inexpensive framegrabber. The circuitry separates horizontal synchronizing pulses from a camera output; the pulses increment a counter that sequentially selects each electrophysiological channel on a sample-and-hold multiplexer. The intensity of each horizontal scan line from the multiplexer output represents the amplitude of one sample of each physiological channel. This signal is then multiplexed with the video signal, such that a portion of each video horizontal line represents the physiological data. The combined output is stored together, providing a means for synchronizing the two signals during analysis. The design allows easy coordination of electrophysiological events with video images from a standard video camera, avoiding the necessity for separate analog to digital circuitry for physiological and video signal storage on computer media, as well as the need for complex synchronization of the data from different media.

RF Closed Loop Checkout of the Agena Vehicle

On a given missile range, it may be necessary to perform Radio Frequency tests on missiles or space vehicles. If there are many complexes on the launch base, RF transmissions from a complex may interfere with the RF tests on another complex. If RF facilities external to the complex must be used for all RF tests, only one complex at a time may perform RF checkout procedures. A requirement may also exist that dictates all RF transmissions must be secure from reception outside the launch complex. An RF checkout system must then be designed to meet these requirements. Such a system has been designed by the Lockheed Missiles and Space Company, AGE Division, Van Nuys, California. It is known as the RF Closed Loop System. It was designed to checkout VHF FM/FM telemetry and S-Band tracking and command systems in the Agena Vehicle. The RF Closed Loop System includes complete recording capability for TM Video signal storage and permanent records of all quantities associated with vehicle RF transmissions. The system is not necessarily limited to monitoring VHF FM/FM telemetry and S-Band tracking and command systems. It may be changed to accommodate any TM or command system by changing the blockhouse monitoring equipment, such as receivers and other demodulating equipment. One limitation is the frequency bandwidth of the long-run transmission lines. The basic concept of non-radiation of RF transmission outside the launch complex until launch and its development into hardware is the main premise of this paper.