They are free social services as they allow users to send comments, opinions and ratings. This includes a group of tools aimed at hosting and sharing different kinds of digital artefacts such as documents, photographs, videos, presentations and recordings. Luisa Alvite, Leticia Barrionuevo, in Libraries for Users, 2011 File-sharing However, an average rate of 3 Mbps will probably suffice for a system multiplex containing a range of video material (sports, news, current affairs, and so on). To compress difficult sports material up to 6 Mbps may be required during peaks, even with a good MPEG-2 encoder. Variable-bit-rate compression combined with statistical multiplexing is commonly used to keep up with rapid motion while maintaining an efficient multiplex. Video can be more challenging, especially high-motion material such as sports events. Movies can be encoded in high definition at 12 Mbps at MPEG-2 with almost no loss of quality. Standard-definition movies encoded at 3 Mbps using MPEG-2 provide excellent results (by comparison, the average bit rate of a DVD is 4 Mbps). These are determined primarily by the aggressiveness of the compression, the detail and motion in the picture, and the quality of the encoder.Īlthough expert viewers can easily spot digital artifacts in currently available digital video, there is little to no complaint from consumers. Picture quality is a function of the residual digital artifacts. Michael Adams, in Modern Cable Television Technology (Second Edition), 2004 3.6.4 Picture Quality This research is continuing and perhaps the way that the keywords are being entered is off the mark and must be adjusted as further research is needed and is ongoing. Of course, this is not a definitive result as this is a science and an art. The date of birth was also searched for, as this was required input at the time of configuration, but again, nothing was found in the way of digital artifacts. All keywords were entered into the keyword list of EnCase, as GREP, Unicode, and Unicode Big Endian. The same holds true for the console ID and the console serial number searches were conducted for these items, listing each as GREP, Unicode, and Unicode Big Endian, and there were no search hits with these settings. A keyword search was run using a specific e-mail address, and nothing was found in the way of artifacts stored on the drive. The first thing to determine was whether the e-mail address that was used to configure the Live account was retained on the hard drive. In an attempt to ascertain other digital artifacts that could be of use in examining the hard drive, a range of keyword searches were used that were based on several items. See blocking artifacts, mosquito noise, feathering and quantization error.Steven Bolt, in XBOX 360 Forensics, 2011 Other Artifacts When analog material is converted to digital, tiny discrepancies (quantization errors) may result. In digital cameras, artifacts may arise when performing digital zoom. As TV screens become larger, the distortions are more noticeable. The greater the compression used, the more artifacts are likely, and fast motion sequences are a major contributor. See noise.Īrtifacts are a natural byproduct of digital compression methods such as JPEG and MPEG, which permanently discard pixels. The electronic recording of analog videotapes can introduce noise as well. Imperfections in the camera lenses and silver-grain film itself can generate "noise," which appears as tiny background specks, making the image softer. In film, artifacts such as blotches, scratches and flicker are commonly found, especially in older movies. Under intense inspection, one might find artifacts all the time, but a few pixels out of balance or a few milliseconds of abnormal sound often go undetected. Artifacts may or may not be easily detectable. (2) A distortion in an image or sound caused by a limitation or malfunction in the hardware or software. It includes documentation, test plans, images, data files and executable modules. (1) Any element in a software development project. How to Set Up Two-Factor Authentication.How to Record the Screen on Your Windows PC or Mac. How to Convert YouTube Videos to MP3 Files.How to Save Money on Your Cell Phone Bill.How to Free Up Space on Your iPhone or iPad.How to Block Robotexts and Spam Messages.
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