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Absolute Category Rating
Absolute Category Rating (ACR) is a test method used in quality Quality may refer to: Concepts *Quality (business), the ''non-inferiority'' or ''superiority'' of something *Quality (philosophy), an attribute or a property *Quality (physics), in response theory *Energy quality, used in various science discipli ... tests. The levels of the scale are, sorted by quality in decreasing order: * Excellent * Good * Fair * Poor * Bad In this method, a single test condition (generally an image or a video sequence) is presented to the viewers once only. They should then give a quality rating on an ACR scale. Test conditions should be presented in a random order per test person. The ACR scale is evaluated based on numbers that are assigned to the individual items, where ''Excellent'' equals to 5 and ''Bad'' equals to 1. The average numeric score over all experiment participants, for each test condition that was shown, is called the mean opinion score. It may also be used for telephony vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acr Quality Scale
ACR may refer to: Aviation * IATA airport code for Araracuara Airport in Caquetá Department, Colombia * Aircraft Classification Rating Medicine * Albumin/creatinine ratio in urine * ACR gene, encoding the enzyme acrosin * ACR score for rheumatoid arthritis * American College of Radiology * American College of Rheumatology Places * Accrington railway station, UK, National Rail code Railways * Alaska Central Railroad, original name of the Alaska Railroad * Alberta Central Railway, an historical railroad in Alberta, Canada * Algoma Central Railway, a railroad in Northern Ontario, Canada * Anglesey Central Railway, a railroad in Wales, UK Science and technology * Absolute Category Rating, a subjective quality test method * Acumulador de Carga Rápida, a battery electric tram system * Adobe Camera Raw, a raw image file converter * Advanced CANDU reactor, a nuclear reactor * Advanced Communications Riser, a PC slot format * Advanced Contrast Ratio or Dynamic Contrast i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video Quality
Video quality is a characteristic of a video passed through a video transmission or processing system that describes perceived video degradation (typically compared to the original video). Video processing systems may introduce some amount of distortion or artifacts in the video signal that negatively impact the user's perception of the system. For many stakeholders in video production and distribution, ensuring video quality is an important task. Video quality evaluation is performed to describe the quality of a set of video sequences under study. Video quality can be evaluated objectively (by mathematical models) or subjectively (by asking users for their rating). Also, the quality of a system can be determined offline (i.e., in a laboratory setting for developing new codecs or services) or in-service (to monitor and ensure a certain level of quality). From analog to digital video Since the world's first video sequence was recorded and transmitted, many video processing systems ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean Opinion Score
Mean opinion score (MOS) is a measure used in the domain of Quality of Experience and telecommunications engineering, representing overall quality of a stimulus or system. It is the arithmetic mean over all individual "values on a predefined scale that a subject assigns to his opinion of the performance of a system quality". Such ratings are usually gathered in a subjective quality evaluation test, but they can also be algorithmically estimated. MOS is a commonly used measure for video, audio, and audiovisual quality evaluation, but not restricted to those modalities. ITU-T has defined several ways of referring to a MOS in RecommendatioITU-T P.800.1 depending on whether the score was obtained from audiovisual, conversational, listening, talking, or video quality tests. Rating scales and mathematical definition The MOS is expressed as a single rational number, typically in the range 1–5, where 1 is lowest perceived quality, and 5 is the highest perceived quality. Other MOS rang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subjective Video Quality
Subjective video quality is video quality as experienced by humans. It is concerned with how video is perceived by a viewer (also called "observer" or "subject") and designates their opinion on a particular video sequence. It is related to the field of Quality of Experience. Measuring subjective video quality is necessary because objective quality assessment algorithms such as PSNR have been shown to correlate poorly with subjective ratings. Subjective ratings may also be used as ground truth to develop new algorithms. Subjective video quality tests are psychophysical experiments in which a number of viewers rate a given set of stimuli. These tests are quite expensive in terms of time (preparation and running) and human resources and must therefore be carefully designed. In subjective video quality tests, typically, SRCs ("Sources", i.e. original video sequences) are treated with various conditions (HRCs for "Hypothetical Reference Circuits") to generate PVSs ("Processed Video ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
