Video Cassette Recorder Research Articles

Lobster trap video: in situ video surveillance of the behaviour of Homarus americanus in and around traps

A lobster-trap video (LTV) system was developed to determine how lobster traps fish for Homarus americanus and how behavioural interactions in and around traps influence catch. LTV consists of a low-light camera and time-lapse video cassette recorder (VCR) mounted to a standard trap with optional red LED arrays for night observations. This self-contained system is deployed like a standard lobster trap and can collect continuous video recordings for >24 h. Data are presented for 13 daytime deployments of LTV (114 h of observation) and 4 day and night deployments (89 h of observation) in a sandy habitat off the coast of New Hampshire, USA. Analyses of videotapes revealed that traps caught only 6% of the lobsters that entered while allowing 94% to escape. Of those that escaped, 72% left through the entrance and 28% through the escape vent. Lobsters entered the trap at similar rates during the day and night and in sandy and rocky habitats. Lobsters generally began to approach the trap very shortly after deployment, and many appeared to approach several times before entering. These data confirm the results of previous laboratory-based studies in demonstrating that behavioural interactions in and around traps strongly influence the ultimate catch.

Direct converting DV into MPEG-2 intra coding

Converting the digital video (DV) format for digital video cassette recorders into the MPEG-2 intra coding is performed in the DCT domain to reduce conversion steps. To convert the 4:1:1 to the 4:2:2 chroma. formats and the 2-4-8 DCT mode to the 8-8 DCT mode, a matrix is multiplied by transformed data. Such multiplication enables parallel processing, and the m_quant of the MPEG-2 TM5 rate control is computed in the DCT domain.

Power measurements and national energy consumption of televisions and videocassette recorders in the USA

The combined energy consumption of US televisions and videocassette recorders was about 40 TW h per year in 1998, corresponding to 3.6% of national residential electricity consumption. The average household television energy consumption was about 310 kW h per year, 23% of which was used while the units were not active. The average household videocassette recorder energy use was about 100 kW h per year, 95% of which was used while the units were not active.

Low-complexity rate-distortion optimal transcoding of MPEG I-frames

The transcoding of MPEG video streams is important in a variety of situations such as in rate reduction for small bandwidth downstream channels and in extracting a fast visual playback stream for digital video cassette recorders. This paper addresses transcoding of MPEG intra-coded frames by selectively copying DCT AC coefficients from the primary MPEG stream into the secondary MPEG stream. A rate-distortion optimal transcoding approach, as well as several computationally more attractive suboptimal approaches, is presented. The proposed solutions outperform the more traditional codeword extraction methods from literature.

New Products of the 1980s and 1990s: The Diffusion of Household Technology in the Decade 1985-1995

The management of our households and the way we spend our leisure time has been greatly influenced by the introduction of various household technologies in the 1980s and 1990s. This paper compares the extent and rate of adoption of selected household products in Australian households. The diffusion of colour television sets, video cassette recorders, compact disc players, microwave ovens and personal computers into various types of households during the 1980s and 1990s was examined. This study found that different types of Australian households adopted new technology at different rates. The levels of ownership of various household technologies were highest for households with children. In general, one-adult households were slower to adopt new household technology when compared to other types of households. This paper speculates as to why one-person households are slower to purchase the latest in cooking and entertainment technology.

Computer-aided video exposure monitoring.

A computer-aided video exposure monitoring system was used to record exposure information. The system comprised a handheld camcorder, portable video cassette recorder, radio-telemetry transmitter/receiver, and handheld or notebook computers for remote data logging, photoionization gas/vapor detectors (PIDs), and a personal aerosol monitor. The following workplaces were surveyed using the system: dry cleaning establishments--monitoring tetrachoroethylene in the air and in breath; printing works--monitoring white spirit type solvent; tire manufacturing factory--monitoring rubber fume; and a slate quarry--monitoring respirable dust and quartz. The system based on the handheld computer, in particular, simplified the data acquisition process compared with earlier systems in use by our laboratory. The equipment is more compact and easier to operate, and allows more accurate calibration of the instrument reading on the video image. Although a variety of data display formats are possible, the best format for videos intended for educational and training purposes was the review-preview chart superimposed on the video image of the work process. Recommendations for reducing exposure by engineering or by modifying work practice were possible through use of the video exposure system in the dry cleaning and tire manufacturing applications. The slate quarry work illustrated how the technique can be used to test ventilation configurations quickly to see their effect on the worker's personal exposure.

The Diagnostic Validity of Digitally Captured Intraoperative Transesophageal Echocardiography Examinations Compared with Analog Recordings: A Pilot Study

Background: Digital acquisition and storage of echocardiographic studies offer many advantages over analog recordings, but the amount of computer memory required may be large. “Computer compression” of data is done by machines with various algorithms. “Clinical compression” involves limiting the recordings to 1-beat loops, and although it is commonly used, its diagnostic validity has not been demonstrated in the operating room. Methods: This prospective pilot study looked at 51 patients undergoing transesophageal echocardiography during cardiac surgery. During continuous videocassette recording, we captured digital loops to demonstrate wall motion abnormalities, ventricular systolic function, aortic insufficiency, and mitral regurgitation. Experts reviewed the loops and tapes. We then compared the diagnoses from the 2 methods. Results: There were major differences in the diagnosis of wall motion between loops and tapes in only 3.4% of myocardial segments. No major differences were seen in the diagnosis of systolic function, aortic insufficiency, or mitral regurgitation in any patients. Conclusion: We conclude that clinical compression is a suitable method to compress data in the operating room. Large numbers of patients are required to definitively demonstrate the small differences. (J Am Soc Echocardiogr 1999;12:974-80.)

Association of obesity with physical activity, television programs and other forms of video viewing among children in Mexico city.

To assess the association of physical activity, television program viewing and other forms of video viewing with the prevalence of obesity among school children. Cross-sectional study. 712 children, 9-16 y old, from a low- and a middle-income town in the Mexico City area. Children completed a self administered questionnaire to assess time spent in physical activity and television viewing, and diet. Height weight and triceps skinfolds were measured. The outcome variable was obesity, and the covariates were hours of television programs and other video viewing, physical activity, energy intake, percentage of energy from fat, town of location of school, age, gender and perception of mother's weight status. Among 461 children with complete information, 24% were classified as obese. Children reported an average of 4.1 +/- 2.2 h/d watching television (2.4 +/- 1.5 h/d for TV programs and 1.7 +/- 1.5 h/d for video cassette recorder (VCR) or videogames), and 1.8 +/- 1.3 h/d in moderate and vigorous physical activities. Odds ratios (OR) of obesity were 12% higher for each hour of television program viewing per day (OR = 1.12, 95% confidence interval (CI) 1.02,-1.22), and 10% lower for each hour of moderate/vigorous physical activity per day (OR = 0.90, 95% CI 0.83-0.98), controlling for age, gender, town and perception of mother's weight status. Children in the middle-income town had higher adjusted odds of obesity (OR = 2.58, 95% CI 1.47-4.54). Physical activity and television viewing, but not VCR/videogames use, were related to obesity prevalence in Mexican children 9-16 y old.

Handwashing before entering the intensive care unit: What we learned from continuous video-camera surveillance

Handwashing is one of the most important factors in controlling the spread of bacteria and in preventing the development of infections. This simple procedure does not have a high compliance rate. The Association for Professionals in Infection Control and Epidemiology, Inc, guideline recommends that hands must be washed before and after patient contact. In our intensive care unit (ICU), we have made it a rule that everyone should wash their hands before entering the ICU. The purpose of this study was to ascertain the handwashing compliance of all personnel and visitors to the ICU. A ceiling-mounted video camera connected to a time-lapse video cassette recorder recorded each person’s actions when they entered the ICU during a 7-day period. Handwashing compliance was assessed for 3 different categories: ICU personnel, non-ICU personnel, and visitors to patients. There were 1030 entries to the ICU during the observation period. ICU personnel complied with handwashing in 71% of entries, non-ICU personnel in 74% of entries, and visitors to patients in 94% of entries. Handwashing compliance by visitors to patients was significantly higher than among personnel ( P < .001). Handwashing compliance among personnel before entering the ICU was low. Continuous effort is needed to raise awareness of the handwashing issue, not only to ensure compliance with APIC recommendations but also in our facility, to ensure that health care personnel wash their hands on entry to the ICU. (AJIC Am J Infect Control 1999;27:367-9)

Uterine Motility in the Cow During Puerperium

SummaryThe objective of the study was to determine uterine motility during the postpartum period in cattle. In the present study spontaneous uterine activity was recorded during postpartum period using electrodes which were surgically implanted into the myometrium 4‐6 weeks before parturition. After the placenta has been released 4‐8 hours post part, spontaneous uterine motility drastically decreased until the second week post part. The effects of oxytocin, depotocin, prostaglandin, ergometrin, detomidin on the uterine contractility, during postpartum period were investigated. Oxytocin and carbotocin given intravenously always provoked strong uterine contractions. Prostaglandin F2alpha and detomidinum HC1 stimulated uterine activity in the early puerperium. Following administration of ergometrin unequal response was recorded. Ultrasonographic examinations were performed daily with real time B‐mode scanner equipped with a 5.0 MHz linear‐array transducer (Aloka 210, Pie Medical). 10 muciparous Black‐White‐Holstein cows between 2 and 4 years old and 550‐650 kg b.w. were used. A 6‐min scan of the longitudinal view of the uterine body was recorded using video cassette recorder connected to the ultrasound scanner. A scoring system was used to determines uterine motility. Contractility scores were higher just after parturition then in the following times. Blood samples were collected daily from jugular vein for plasma progesterone and estrogen concentrations. Changes in uterine activity were associated with plasma progesterone and estrogen level.

A real-time digital VCR encode/decode and MPEG-2 decode LSI implemented on a dual-issue RISC processor

A real-time system large-scale-integrated circuit (LSI) for digital video cassette recorder (DVCR) encoding/decoding and MPEG-2 decoding is implemented on a dual-issue RISC processor (DRISC) with dedicated hardware optimized for video-block processing. The DRISC achieves 972-MOPS software performance and can execute fixed-length data processing at the block level as well as processing at the macro-block level and above for the DVCR/MPEG-2. The dedicated hardware for variable-length coding/decoding can encode and decode codes for both the DVCR and the MPEG-2 by changing translation tables. The dedicated hardware for video-block loading can process video-block data transfers with half-pel operations. The LSI size is 7.7/spl times/7.2 mm/sup 2/ in a 0.25-/spl mu/m CMOS process.

Single-pass constant- and variable-bit-rate MPEG-2 video compression

Most real-time MPEG-2 encoders are designed to perform in a constant-bit-rate (CBR) mode, in which buffer constraints are imposed to circumvent large deviations from a desired rate at any instant in time. Although such streams are generally good-quality sequences, certain types of operations or environments call for a more efficient real-time CBR encoder. The first part of the paper describes how a better-quality CBR video stream can be produced by estimating the relative complexity of a picture in comparison with the average complexity of the partially encoded stream and using it to adjust the compression parameters in a single-pass mode of operation. Our CBR encoder is particularly attractive for digital broadcast and editing environments, in which representations of higher-fidelity video objects in both display and freeze modes are constantly pursued. The second part of the paper describes the real-time generation of video streams with a variable-bit-rate (VBR) encoder. This mode of operation is high ly desirable for home entertainment and recreational events. We propose a robust single-pass VBR video encoder algorithm which is capable of learning and adapting itself to the complexity of image segments and thereafter creating streams which have constant visual picture quality. The new VBR scheme displays a better performance than the CBR encoder, particularly when special effects such as scene transitions, fades, or luminance changes are to be compressed. Both CBR and VBR encoders are fully compliant with the MPEG-2 standard and are easily implementable with IBM encoder architecture. Compression results for the new single-pass encoding algorithms and comparisons with previous CBR schemes are provided. The result suggests the suitability of our VBR approach for record/playback in storage media such as digital video disc (DVD) players, disk-based camcorders, and digital videocassette recorders (DVCRs). It further reflects the importance of our single-pass CBR scheme for providers of broadcast services , for which it allows more video programs to be allocated to a selected communication link, and for in-studio applications, for which it greatly facilitates visual analysis of captured streams.

A simultaneous model for innovative product categorysales diffusion and competitive dynamics

Diffusion of innovation has been the focus of an entire stream of research in marketing, and firm entry and exit decisions have been investigated by marketers, strategists, and economists. However, little attention has been paid to the relationship between changing demand and the entry and exit behaviors of competitors in the marketplace. Understanding this relationship is essential in making resource commitments, as profitability of options depends not only on the size and growth of the market, but also on the number of competitors likely to be encountered. This is particularly important in innovative markets, where changes occur rapidly and one cannot assume that either customer needs or competitors faced tomorrow will be the same as today. We simultaneously model demand and number of competitors, including the interactive relationship between these dynamics in the marketplace, and empirically investigate three technology-intensive markets—video cassette recorders, personal computers, and workstations. Our results suggest that competition and demand impact entry and exit, but that the nature of this impact may depend on whether or not a `shakeout' has occurred in the marketplace. Further, an increasing number of competitors may lead to improved marketplace offerings, resulting in demand expansion.

The Usability of Time-Setting Functions on Small Electronic Consumer Products: A Test

Five common time-setting methods of small electronic consumer products (e.g., video cassette recorders or clock radios) were examined. The aim of the study was to test whether an additional AM/PM button would provide shortcuts for the process of setting the time and whether a standard numeric patch was the most effective way to set a clock. Furthermore, the study was intended to gather data leading to improvements in the interfaces of domestic appliances. Evaluation of usability was achieved by a comparative usability test using a touchscreen monitor. Information about users' subjective impressions was gathered via a questionnaire. The numeric patch was the superior method of setting the time. The introduced AM/PM button provided valuable shortcuts and was widely accepted by participants. Furthermore, several shortcomings of the tested time-setting mechanisms were discovered, and suggestions for the improvement of the products were made.

Discussion

We present a method of synchronizing a shutter for a video camera that allows an instantaneous slow-motion visualization of fast repetitive processes with a time scaling factor of up to 1,000,000 or more. The method uses standard, unmodified CCIR or EIA video equipment, including video cassette recorders for low-cost recording. A number of examples showing spatio-temporal dynamics in nonlinear optical systems is shown, including magneto-optical beam-splitting, drifting hexagons and phase synchronization of coupled solid-state lasers.

Observing Pattern Dynamics in Nonlinear Optical Systems Using the Video-sampling Method

We present a method of synchronizing a shutter for a video camera that allows an instantaneous slow-motion visualization of fast repetitive processes with a time scaling factor of up to 1,000,000 or more. The method uses standard, unmodified CCIR or EIA video equipment, including video cassette recorders for low-cost recording. A number of examples showing spatio-temporal dynamics in nonlinear optical systems is shown, including magneto-optical beam-splitting, drifting hexagons and phase synchronization of coupled solid-state lasers.

Magnetic force microscopic study of magnetic tapes recorded at MHz frequencies

We have undertaken a comparative study of recorded signals on a standard video tape using a magnetic force microscope (MFM) and a recording head. The tapes examined were coated with the usual iron oxide particles but had different values of residual magnetisation and coercivity. They were magnetised by recording a sinusoidal signal in the frequency range 1 to 9 MHz corresponding to a wavelength of 5.8 to 0.64 μm. These recordings were made using a standard VHS home video cassette recorder with the recording current set to near its optimum value. Samples for MFM measurement were made by cutting material from the recorded tapes. The response of the MFM showed a higher value for the better quality tapes where the quality was determined by the product BrHc. The response of the microscope decreased with increasing spacing height of the tip in broad agreement with the standard theory. The recording frequency dependence of the MFM response had a maximum at about 3–4 MHz and then decreased rapidly with increasing frequency. The output from a standard recording head showed a similar frequency dependence to the MFM response.

Origins of friction and wear of the thin metallic layer of metal evaporated magnetic tape

The origins of friction and wear of the thin metallic layer of metal evaporated (ME) magnetic tapes were determined at an asperity level using a modified commercial video cassette recorder (VCR) as a tape transport, magnetometer and tribometer. The VCR was instrumented to measure friction force between the rotary heads and tape, head-to-tape spacing to nanometer vertical resolution, and sub-microsecond duration signal dropouts caused by loose wear debris particles in the head-to-tape contact interface. ME tapes with various surface texture and the same lubricant thickness were studied, as well as tapes with various lubricant thickness and the same surface texture. To measure the very subtle origins of wear, tapes were recorded and then played back only one time, and surface topography was measured with an atomic force microscope to see if the tapes were worn. For fixed asperity size, increased asperity areal density or more numerous asperities reduced the plastic deformation that was observed at low asperity areal densities. Having more asperities increases the load bearing area near the highest point on the tape. This prevents high strain and associated plastic deformation of high asperities. Thus, spreading the load over more asperities reduces plastic deformation, and deformation becomes primarily elastic. Tapes that exhibited plastic deformation had higher friction force than the tape that exhibited elastic deformation. A simple model was developed which suggests that high friction force is not due to the energy required to plastically deform the asperities, but arises from high real area of contact during sliding for the tapes that plastically deform which is consistent with plasticity theory in the presence of a tangential force. Tapes that plastically deform do not exhibit higher signal dropout frequencies, and this implies that plastic deformation is not associated with loose wear debris particle formation. For smooth tapes with high isolated asperities, cohesive material failure of asperities due to shear stress brought on by friction force resulted in loose wear debris generation, high plowing component to friction force and interface instability. A thicker lubricant layer reduced friction force by reducing the shear strength of adhesive contact junctions.

A universal information appliance

The consumer's view of a universal information appliance (UIA) is a personal device, such as a PDA (personal digital assistant) or a wearable computer that can interact with any application, access any information store, or remotely operate any electronic device. The technologist's view of the UIA is a portable computer, communicating over a bi-directional wireless link to an elaborate software system through which all programs, information stores, and electronic devices can export their interfaces to the UIA. Using an exported interface, the UIA can interoperate with the exporting entity, whether a home security system, a video cassette recorder, corporate application, or an automobile navigation system. Furthermore, interfaces presented by the UIA can be tailored to the user's context, such as the user's preferences, behavior, and current surroundings. The UIA programming model supports dynamic interface style and content triggered on activity detected from the user's real-world and software context. In this paper we describe the design and first implementation of a UIA, a PDA that, through a wireless link, can interact with any program, access any database, or direct most electronic devices through a remote interface. The UIA model uses IBM's TSpaces software package as the interface delivery mechanism and resource database, and as the network communication glue. TSpaces supports communication between the UIA and any peer over a dual-mode wireless link. Using a popular application example, we present a generalized architecture in which the UIA is the mobile user's software portal for interoperating with any peer: another UIA, a common network service, a legacy application, or an electronic device.

Southwest Home Horticulture: Using Video and the Internet in the Instruction of Nonmajors

A distance learning course called Southwest Home Horticulture was developed and implemented at Arizona State University using video and Internet technologies to give nonhorticulture students an overview of urban horticulture in the southwestern United States. Fourteen, one-half-hour video programs about topics in southwestern residential landscaping, plants materials and landscape best-management practices were produced in ≈800 working hours. The video programs are now telecast weekly, each academic semester, on the regional public television station and the educational channel of several cable television systems. We found that students who enrolled in the course were most likely to tape the programs on a video cassette recorder and watch them at their own convenience, one to three times. A World Wide Web (Web) site on the Internet was developed as a supplement to the video programs. The Web site was organized into a modular format giving students quick access to auxiliary course-related information and helpful resources. When asked, ≈90% of the students indicated that the Web site was a helpful supplement to the video programs. Use of video and Internet technologies in tandem has enabled nonhorticulture major students to learn about home horticulture in an asynchronous or location and time independent fashion.