Audio / Video Terms Glossary
| Term | Description |
|---|---|
| 2 piece projection | A 2 piece projection system consists of a light engine shining light onto a screen. The light engine can be placed in front of (front projection) or behind (rear projection) the screen |
| 2/3 pulldown | a method of video processing that converts content shot at film (24fps) to video (30fps). This helps reduce motion artifacts when watching film based content on a television |
| Active HDMI Cable | An HDMI cable augmented by captive electronics for signal equalization, which uses power drawn through the HDMI connector or from an external power supply, enabling longer cable lengths than are possible with passive only. This category may also include pluggable active equalizers, such as dongles, which attach to one or both ends of a passive HDMI cable, creating an active cable system. |
| Active Optical Cable (AOC) | A hybrid HDMI cable that uses a combination of optical fiber strands and parallel copper wires to transmit audiovisual, auxiliary data, and power. These may support longer lengths than an all-copper active HDMI cable, also typically in a thinner physical profile. |
| ADA | Americans with Disabilities Act |
| AI | Artificial Intelligence |
| AIA | American Institute of Architects |
| Analyzer | A test instrument which emulates a Sink Device and analyzes audio, video, and metadata received for calibration or troubleshooting of audio and video systems. Analyzers usually have an EDID Emulator that allows various EDIDs to be presented in order to coax various signals from a Source device for testing purposes. Some Analyzers are paired with a Generator (in the same or separate chassis) to allow emulation of a Repeater and/or passive monitoring (encrypted link analysis) between Source and Sink Devices. |
| AOC (Active Optical Cable) | A hybrid HDMI cable that transmits data over a fiber optic cable inside of the HDMI cable. Copper is still used for some things such as 5v hotplug and DDC |
| APEX | Audiovisual Provider of Excellence; AVIXA program that honors member companies that achieve certain levels of employee certification and training |
| AR | augmented reality formerly thought of as a gimmick, we're seeing its use in more creative display projects each year. AR allows a user to interact with a virtual environment either in person or remotely |
| ARC | ARC, or Audio Return Channel is a feature built in to most home theater products that allows audio to travel from a display back to an audio source such as an AVR or soundbar. ARC utilizes the HDMI cable that connects the audio device to display, eliminating the need for a second audio cable such as optical. To add, the ARC channel on the HDMI cable can transmit advanced audio formats that optical cannot, therefore HDMI ARC is more desired in higher performance installations. |
| ARC RX | An interface capable of receiving audio via ARC from a device that includes an ARC transmitter (TX) interface. |
| ARC TX | An interface capable of transmitting audio via ARC to a device that includes an ARC receiver (RX) interface. |
| Auto Lipsync (ALS) | Added in HDMI 1.3, ALS Correction is a feature that will automatically synchronize the image on a display to the sound from a separate audio device. NOTE: Both video and audio devices need to support ALS for it to work as intended. |
| AVB | Audio Video Bridging |
| A/V Switch | A device used to route audio/video signals from a source to 2 or more different destinations |
| AVIXA | Audiovisual and Integrated Experience Association, producer of InfoComm trade shows around the world, co-owner of Integrated Systems Europe and the international trade association representing the audiovisual industry. |
| AVoIP | AV over IP is a method of transferring audio visual data over an IP network. |
| AVR | Audio/Video Receiver. An audio amplifier and audio/video (A/V) switching combination device for a home theater. It contains inputs for all of the audio and video sources and outputs to one or more sets of speakers and one or more monitors or TVs. |
| Backlight | The light source of an LCD panel. Most commonly CCFL bulb(s) or LEDs |
| Backlit | Refers to the light source of an LCD TV being behind the panel (rather than the light source being across the bottom or along the edges -see Edgelit) |
| Banding | Video artifact visible as abrupt changes or steps between shades of the same color in place of fine gradations. Symptom of insufficient bit depth in the signal. |
| Bandwidth | Maximum aggregate rate of data transfer across a given path. Main channel data transfer rates and typically measured in giga-bits-per-second (Gbps). |
| BICSI | Building Industry Consulting Service International tackles information technology and communication systems education. |
| BIM | Building Information Modeling |
| BLC | Business and Leadership Conference; provides integration firm leaders with business insight, camaraderie, and innovation to help them improve sales and leadership skills. |
| Brightness | (TV control) How much gain is taken away from the red, green, and blue signal. Also known as black level |
| BT.601 (also rec. 601) | standard established in 1982 that describes the parameters (resolution, frame rate, color space, etc) for SDTV |
| BT.709 (also called Rec. 709) | ITU-R standard established in 1990 that describes the parameters (resolution, frame rate, color space, etc.) for high definition television (HDTV). The latest revision at time of publication is Recommendation ITU-R BT.709-6. |
| BT.2020 (also called Rec. 2020) | ITU-R standard established in 2012 that describes the parameters (resolution, frame rate, color space, etc.) for Ultra-High Definition (UHD) television. The BT.2020 RGB color space defines an electronic container that encompasses the lesser BT.601, BT.709, and DCI-P3 containers. |
| BYOD | Bring Your Own Device; a trend in corporate meeting spaces where customers are demanding the capability to join a meeting using only the tech they bring to it, such as a smartphone or laptop. |
| CalMAN | Software package used to calibrate and evaluate displays. Made by Portrait Displays |
| CEC | Consumer Electronics Control. An HDMI protocol that supports the use of a single remote control to command multiple devices that are connected to each other through HDMI. |
| Capabilities Data Structure (CDS) | A data structure used to signal capabilities of an eARC receiver to an eARC transmitter. |
| Category cable | 4x twisted pair copper cable as defined by Telecommunications Industry Association (TIA). Most commonly used in Ethernet networks. For example, Cat 6, Cat 6A. |
| CCTV | Closed-Caption Television. A type security/surveillance system that uses cameras and displays to monitor activity of a specific space or property |
| CEDIA | Custom Electronic Design & Installation Association. the global industry association and central touch point for residential technology. CEDIA provides members with cutting-edge education, develops standards to ensure the highest levels of professionalism, and is the industry's only certifying body. |
| Chroma Subsampling | is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance. Typically described as a ratio of the luminance channel to the 2 color channels ex 4:4:4, 4:2:2, 4:2:0 |
| CIE chart | Created by the International Commission on Illumination (CIE) in 1931, the chart shows the range of colors in the visible light spectrum |
| Clipping | when a signal is overdriven which results in distortion and/or loss of detail. In video, clipping most commonly refers to contrast or color levels being too high, causing details to be lost. In audio, a clipped signal usually sounds like distortion and can be dangerous to audio equipment. |
| CMS | (TV control) Color Management System. A set of controls in some displays that allow the calibration of individual primary and secondary colors |
| CompTIA | Computing Technology Industry Association; association of over 8,000 companies providing IT certifications. |
| Contrast | (TV control) How much gain is added to the red, green, and blue signal. Also known as white level |
| Colorimeter | See Tristimulus Colorimeter |
| Color saturation | (TV control) The amount of color in the image |
| Color space/color gamut | (TV control) The range of colors that a display can produce. |
| Color points | Targets for the primary and secondary colors within the CIE chart |
| Color Temperature (Kelvin) | The color of light as described by the Black Body Curve. As things heat up, they change color. A cool color temperature (9500K) may look blue-ish white while a warm color temperature (3500k) may look orange-ish white |
| Crushing | Video calibration term that describes the loss of shadow detail when brightness/black level is set too low. In video this may be caused by signal path errors. |
| CTA | Consumer Technology Association; producers of CES (Consumer Electronics Show) |
| CTS / CTS-D / CTS-I | Certified Technology Specialist; AVIXA's pro AV certification program (D for design; I for installation) |
| D65 | the standard color of white as defined by the CIE. the coordinates for D65 on the CIE chart are x=.313, y=.329. D65 resembles daylight |
| DCI-P3 | RGB color space defined by the Digital Cinema Initiatives (DCI) specification, a joint venture of several motion picture studios to define standards for the digital cinema industry. P3 covers approximately 45.5% of the human visible color spectrum (fitting between ITU-R BT.709 and BT.2020) and was published by the SMPTE. |
| DCI/P3 | (DCI = Digital Cinema Initiatives) a common RGB color space for digital movie projection from the American film industry. DCI-P3 was defined by the Digital Cinema Initiatives (DCI) organization and published by the Society of Motion Picture and Television Engineers (SMPTE) |
| Digital Visual Interface (DVI) | Transport interface for connecting a digital video source such as computer graphics card to a display device such as a computer monitor. Predates and is compatible with HDMI. |
| Display Data Channel (DDC) | A two-wire communication bus in HDMI comprising one serial data (SDA) and one serial clock (SCL) channel, based on the Philips Inter-integrated circuit (I2C) communications specification. DDC bi-directional protocols include E-EDID, HDCP authentication and link integrity check, and establishment of HDMI version and bandwidth compatibilities. |
| Display Stream Compression (DSC) | Light compression codec by VESA, introduced to HDMI with version 2.1 for optional support of video formats that otherwise require higher bandwidth than is available, or to reduce cable stress in transmitting existing formats at lower bandwidth. |
| Dolby Laboratories | an American company specializing in audio noise reduction and audio encoding/compression. Dolby licenses its technologies to consumer electronics manufacturers. |
| Dolby Digital | a proprietary surround sound format made by Dolby Laboratories. Dolby Digital supports up to 5.1 speaker configuration with a max bandwidth of 640kbps |
| Dolby Digital Plus | a proprietary surround sound format made by Dolby Laboratories. Dolby Digital supports up to 7.1 speaker configuration with a max bandwidth of 1.7mbps |
| Dolby TrueHD | a proprietary surround sound format made by Dolby Laboratories. Dolby Digital supports up to 7.1 speaker configuration with a max bandwidth of 18mbps. Dolby TrueHD is considered lossless |
| Dolby Atmos | a proprietary immersive surround sound technology developed by Dolby Laboratories. It expands on existing surround sound systems by adding height channels, allowing sounds to be interpreted as three-dimensional objects. Dolby Atmos can utilize up to 128 channels of sound routed to up to 64 speakers. Dolby Atmos uses Dolby TrueHD as the base layer of the audio stream, but also adds per channel metadata. |
| Dolby Vision | A proprietary HDR system designed to react to individual display technologies and presented differently based on a display's actual capability. It uses the SMPTE ST 2084 (PQ) EOTF with static metadata or SMPTE ST 2094-10 with dynamic (frame-by-frame) metadata, 10- or 12-bit color depth, up to Rec. 2020 color gamut, and a maximum of 10,000 cd/m2 brightness. |
| Dolby MAT | Dolby Metadata-enhanced Audio Transmission. An audio format used for the transmission and distribution of multichannel audio and accompanying metadata over high-resolution interfaces. |
| DSCE / DSDE / DSNE / DCME / DSSP | The certifications for the digital signage industry as adopted by the DSE, DSF, and ISA. They stand for: |
| Digital Signage Certified Expert ( DSCE) the fundamentals course | |
| Digital Signage Display Expert (DSDE) on displays | |
| Digital Signage Network Expert (DSNE) on networks | |
| Digital Content and Media Ex[pert (DCME) on content and media | |
| Digital Signage Sales Professional (DSSP) | |
| DSE | Digital Signage Expo; world's largest trade show dedicated to showcasing digital display and interactive technology solutions. |
| DSE | Dirty Screen Effect. Used to describe the lack of uniformity of a display. DSE is especially noticeable when viewing full screen light grey or dark grey test patterns. |
| DSF | Digital Signage Federation; not-for-profit trade group representing the digital signage industry and founders of the DSE (Digital Signage Expo). |
| DSP | Digital Signal Processing. The act of manipulating an audio/video signal to achieve a specific effect such as reverb |
| DTS Inc | An American company that makes multichannel audio technologies for film and video. Based in Calabasas, California, the company introduced its DTS technology in 1993 as a higher-quality competitor to Dolby Laboratories, incorporating DTS in the film Jurassic Park (1993). The DTS product is used in surround sound formats for both commercial/theatrical and consumer-grade applications- |
| DTS Digital Sound | a proprietary surround sound format made by DTS, Inc. DTS supports up to 5.1 speaker configuration with a max bandwidth of 1.5mbps |
| DTS-HD | a proprietary surround sound format made by DTS, Inc. DTS-HD supports up to 7.1 speaker configuration with a max bandwidth of 6 mbps |
| DTS-HD Master Audio | a proprietary surround sound format made by DTS, Inc. DTS-HD master Audio supports up to 7.1 speaker configuration with a max bandwidth of 24.5mbps. DTS-HD Master Audio is considered lossless. |
| DTS:X | a proprietary immersive audio format designed by DTS, Inc that can place sound in more specific locations around the room compared to standard 5.1 or 7.1 speaker configuration. DTS:X can support up to 32 speaker locations and up to an 11.2-channel system. DTS:X uses the DTS-HD Master Audio format as the base layer of the audio stream |
| Dynamic range | Considered the most important quality of any video or audio system! |
| As a video term: dynamic range describes the difference between how bright and how dark an image or a display is. | |
| As an audio term: dynamic range describes the difference between the quietest and loudest a piece of music or an audio system is | |
| eARC | Enhanced Audio Return Channel. An enhanced version of the HDMI Audio Return Channel (ARC) feature that includes support for higher data rates of uncompressed and compressed audio, support for Dolby Metadata-enhanced Audio Transmission (MAT), and operation without reliance on Consumer Electronics Control (CEC). |
| eARC RX | An interface capable of receiving audio via eARC from a device that includes an eARC transmitter (TX) interface. |
| eARC TX | An interface capable of transmitting audio via eARC to a device that includes an eARC receiver (RX) interface. |
| Edge Enhancement | a video artifact (distortion) that can be seen around objects on a display. This is typically a symptom of the display's sharpness control being set too high. Edge Enhancement can also be the result of processing errors in the content itself or from another device in the signal chain |
| Edgelit | Refers to the light source of an LCD TV located around the edges of the panel (rather than the light source being directly behind the LCD panel -see Backlit) |
| Extended Display Identification Data (EDID) | A data block standardized by VESA which is stored in a repeater or display's read-only memory. EDID is used to communicate to a video source the supported video resolutions, color formats, timings and feature support (such as HDR and 3D), along with audio format capabilities. HDMI also uses E-EDID (Enhanced EDID) that adds the display's preferred formats and timings to influence the media that a Source should send, if available. |
| Electro Optical Transfer Function (EOTF) | The process which defines the converting an incoming video signal to light (formally gamma in a display)(see gamma). |
| Extender Device | Any two-piece system designed for the purpose of extending transmission distance for signals including (but not limited to) HDMI and its properties, control, power, network, or other digital signals. These devices typically include a Transmitter (encoding device) and a Receiver (decoding device). Most commonly, the systems will interface with a RJ45 or optical fiber connection. |
| ESPA | Electronics Systems Professional Alliance |
| FALD | Full Array Local Dimming. describes a style of backlight on an LCD panel. LEDs are located behind the panel and are divided into zones. Zones can be controlled and adjust in luminance depending on the source material. |
| FCC | Federal Communication Commission regulates interstate communications by radio, television, wire, satellite, and cable. |
| Fixed Rate Link (FRL) | Technology for transmitting high-speed serial data introduced in HDMI 2.1 to support up to an aggregate 48Gbps on the main data channels. It utilizes a tiered set of fixed data rates, instead of the variable pixel frequency-based rates of TMDS. FRL eliminates the TMDS character clock and optionally repurposes the clock channel as a fourth data lane. FRL also optionally introduces light-compression to reduce the bit rate on existing formats, as well as enable next-generation video features such as 8K and 10K resolutions with HFR and HDR. |
| Frame Rate | The number of still images shown per second (fps) to simulate motion. It is most commonly 24 fps and 60 fps with film and video content, respectively. Sometimes high frame rate (HFR) is used (up to 120 fps). |
| Functional Tester | A type of Generator, Analyzer, or Generator/Analyzer combination that emulates real end-products, can learn and clone hardware characteristics, and that is typically used for debugging AV systems by process-of-elimination using go/no-go tests. Functional testers do not typically provide the detailed/certified protocol or physical signals/analysis/reporting required for compliance testing. |
| Gamma | (TV control) Defines the relationship between the incoming video signal and the light output of the display. This is non-linear. Higher Gamma values are better for darker rooms, lower Gamma values are better for brighter rooms. If Gamma is set correctly, shadows in dark movies, TV shows, games, etc., should be visible regardless of room lighting. Gamma is a legacy term for HDTV and earlier video formats are described in UHD systems as SDR EOTF. |
| Generator | A test instrument which emulates a Source device and generates test patterns and/or audio test signals for calibration or troubleshooting of video and/or audio systems. All Generators have an EDID Reader and most include the capability to display and possibly analyze the EDID information read from a Repeater or Sink. |
| Grayscale | The range of gray shades from black to white. When calibrating a display the grayscale is typically calibrated to the D65 industry standard white point (see D65). |
| HDBaseT | A proprietary technology used to transport HDMI signals along with control, power, S/PDIF audio, USB, and Ethernet over long cable lengths, most commonly category cable. |
| High-Bandwidth Digital Content Protection (HDCP) | A mandatory copy protection protocol for the encrypted transmission of all copyrighted media through HDMI to prevent unauthorized duplication. There currently exist two generations: HDCP1 (HDCP 1.3 and 1.4) for 1080p or lower video resolutions, and HDCP2 (HDCP 2.2 and 2.3) for UHD video and high-resolution audio. Types of connections that support HDCP include DisplayPort (DP), Digital Visual Interface (DVI), and High-Definition Multimedia Interface (HDMI) |
| HDMI | High Definition Multimedia Interface. A digital interface that passes audio, video, and communication signals down a single cable |
| HDMI Ethernet and Audio-return Channel (HEAC) | A channel in HDMI composed of a differential mode twisted pair to support up to 100 Mbps HDMI Ethernet Channel (HEC) and Audio Return Channel (ARC). Repurposed to eARC in HDMI 2.1. |
| HDMI Protocols | Digital message formats within the HDMI connection that manage high speed and auxiliary communications between devices, as governed by the HDMI specification. Examples include CEC and HDCP. |
| High Dynamic Range (HDR) video | Greater dynamic range than standard video imaging. Various HDR formats are applied to content and interpreted by displays to achieve an HDR effect. The brightness capabilities of an HDR display are described by the maximum peak luminance. |
| HDR10 | The first consumer HDR format, being an open standard based on SMPTE ST 2084 EOTF. It uses 10-bit signal (the 10 in HDR10), BT.2020 color gamut, provides for a maximum signal brightness of 10,000 nits, and with static metadata. |
| HDR10+ | Similar to HDR10 but enhanced with dynamic (frame-by-frame) metadata based on SMPTE ST 2094-40. Adoption, licensing, and certification is managed by HDR10+ Technologies, Inc. |
| HEVC | High Efficiency Video Coding. One standard of the many different video compression methods. Also known as H.265. |
| Hot Plug Detect (HPD) | A signal wire, monitored by the Source, which indicates both cable connectivity and the Sink's EDID readability. Hot Plug events can be generated by the Source (via +5 V Power remove/restore), the Sink (via HPD de-assert/re-assert) or the Cable (via disconnect/reconnect). |
| Hybrid Log Gamma (HLG) | HDR open standard developed by the British Broadcasting Corporation (BBC) and Japan's Nippon HÅsÅ KyÅkai (NHK) for broadcast TV, especially live events. The name indicates a hybrid of the legacy gamma curve, logarithmically extended to allow headroom for HDR. HLG does not require additional metadata to be delivered in the content (though it may optionally include it), making it backwards compatible with SDR displays. |
| H.264 | one standard of video compression. Most commonly used on Blu-ray discs, iTunes, and more |
| H.265 | one standard of video compression. Also known as High Efficiency Video Coding (HEVC). One successor to H.264. |
| Hue/tint | (TV control) used to manipulate the color gamut or a specific color on a display. A common example would be comparing yellow to a green-ish yellow |
| Immersive Audio | Surround Sound audio that makes use of additional loudspeaker channels placed above the listeners (height channels), and optionally more loudspeaker channels at ear height, to create a more three-dimensional sound field when compared with using only ear-height speakers. |
| Interlaced | The process of generating a image in video by combining even and odd scan lines to make a solid picture |
| IOTA | Industry Outlook and Trends Analysis; a series of pro AV reports by AVIXA that look at particular regions and the global AV market |
| IP Switch | a configurable switch designed to route IP signals to 2 or more destinations |
| ISE | Integrated Systems Europe; the largest pro AV trade show in the world. |
| Joint Object Coding (JOC) | describes the process by which Dolby Digital Plus with Atmos decoders, receiving a legacy 5.1 mix and sideband metadata, are able to reconstruct the original Atmos mix. |
| JSON | JavaScript Object Notation. A lightweight data-interchange format that is easy for humans to read and write, and for machines to parse and generate. |
| KVM switch | Keyboard, Video, Mouse is a hardware device that allows a user to control multiple computers from one or more[1] sets of keyboards, video monitors, and mice. Although multiple computers are connected to the KVM, typically a smaller number of computers can be controlled at any given time. Modern devices have also added the ability to share other peripherals like USB devices and audio. |
| LFE | Low-Frequency Effects. A band-limited channel specifically intended for deep, low-pitched sounds (bass) in an audio system |
| Lossless Digital Audio | A digital audio signal which, when decompressed, provides a perfect bit-for-bit replica of the original signal and therefore reconstitutes all information available in the original. It provides the highest quality audio signal for any application. |
| Lossy Digital Audio | A digital audio signal which, during compression, has had some of the original signal information discarded to reduce the file size or transmission rate. Lossy encoding techniques utilize psychoacoustic principles to discard specific information thought to be superfluous or to have the least effect on sound quality. |
| Laser Phosphor | one type of light engine used in a video projector. Lasers excite a color wheel that is coated in phosphor to produce the colors that you see on the screen |
| LCD | Liquid Crystal Display. Light generated by a backlight shines through a liquid crystal to produce color. The liquid crystals themselves do not actually emit light |
| LED | Light Emitting Diode. A small semiconductor that emits light when current is applied. Most commonly in electronics, such as a backlight for a LCD TV |
| Light meter | used in display calibration to measure light that is emitting from a display (see Tristimulus Colorimeter and Spectroradiometer) |
| Local dimming | The intensity of the light source of the LCD panel (backlight) can adapt based on the content being shown. This allows for more Dynamic Range than typical LCD display |
| Luminance | The intensity of light emitted from a screen. Typically expressed in foot-lamberts (fL), a US customary unit, or candelas per square meter (cd/m2), the derived international standard unit also known as nits. 1 foot-lambert equals 3.42 cd/m2. |
| Macroblocking | a video artifact (distortion) in which objects or areas of a video image appear to be made up of small squares rather than proper detail and smooth edges. |
| MaxCLL (Maximum Content Light Level) | Used as a parameter in HDR10, the MaxCLL is the luminance of the brightest pixel in the content (expressed as nits) |
| Max FALL (Maximum Frame-Average Light Level) | Used as a parameter in HDR10, MaxFALL is the maximum value of the frame-average for all the frames in the content (expressed as nits). |
| Metadata | A collection of data (information) packets combined into the high-speed AV data to provide instructions on particular actions or features for how a Repeater or Sink device should use the AV stream. For example, audio format, or HDR video parameters. |
| MLP | Meridian Lossless Packing is a lossless compression technique for compressing PCM audio data. Developed by Meridian Audio, Ltd |
| MOAR | Market Opportunity Analysis Report; AVIXA reports focused on AV opportunities in particular vertical markets. |
| Motion interpolation | (TV control) video processing that increases the video's frame rate (also known as Soap Opera Effect) |
| Nit | Metric measurement of luminance. Also known as candelas per meter squared (cdm2). 1 foot lambert equals 3.42 nits |
| Noise Reduction | electronically processing noise (a type of distortion) out of the image |
| NSCA | National Systems Contractors Association; not-for-profit association representing the commercial electronic systems industry and founder of such programs as IGNITE, Pivot to Profit, etc. Its annual Business & Leadership Conference gathers integration professionals for strategic presentations and networking. |
| OETF | Opto Electronic Transfer Function. The process of converting light into a video signal. The most common example would be how a camera generates digital information based incoming light |
| OLED | Organic Light Emitting Diode. Thin layer of organic film that emits light when voltage is applied. Commonly used in display manufacturing |
| Passive HDMI cable | An HDMI cable constructed with groupings of electrical conductors that contains no electronics, relying solely on the wires, geometry, and construction of the cable to pass the HDMI signals. Typically used for short length applications. |
| Perceptual Quantization | An electro-optical transfer function (EOTF) curve that models the contrast perception of the human eye, allowing for the most efficient encoding of luminance at a given bit depth. This is critical for high- dynamic range images. |
| PCM | Pulse code modulation. A method that is used to convert analog signals into digital, binary, coded pulses. This is done by sampling the analog signal, quantizing each sample independently, then converting the resulting quantized values into a digital signal. Also known as LPCM or Linear Pulse Code Modulation. |
| Physical Tester | A type of Test Equipment that evaluates the electrical characteristics of a cable, its impedance, and/or voltage waveforms passing through it. An instrument used to directly measure integrity of cabling and signals. |
| Power for Cable Assemblies (PCA) | HDMI 2.1 feature to enable the provision of operating power for PCA-enabled active cables from a compatible Source, alleviating the need for external power. |
| Protocol Tester | A type of Test Equipment that logs events, while monitoring signals passively (as they go by) or while emulating a Sink, Source, and/or Repeater. Used to debug handshaking between a Sink, Source, and/or Repeater, or between a real and emulated Sink, Source, and/or Repeater. |
| Primary colors | colors that can be combined to make any other color in the visible spectrum. In the context of emitted light, the primary colors are Red, Green, and Blue. The primary colors are defined and chosen and based on the human visual system |
| Progressive scan | The process of making an image by showing the entire image at once (vs interlaced which shows even then odd lines simulating a solid image) |
| PSA | Physical Security Association |
| PSIM | Physical Security Information Management |
| PSNI | Professional Systems Network International; alliance of integrators, manufacturers, and distributors around the world and dedicated to creating industry standards. |
| Quantum Dots | very small semiconductor particles, only several nanometers in size, so small that their optical and electronic properties differ from those of larger particles. Many types of quantum dots will emit light of specific frequencies if electricity or light is applied to them, and these frequencies can be precisely tuned by changing the dots' size, shape and material, giving rise to many applications. Commonly used as a backlight system for an LCD panel. |
| Quick Frame Transport (QFT) | A feature introduced with HDMI 2.1 that uses a higher bandwidth link to send video faster than its frame timing dictates, reducing latency and power usage. |
| Quick Media Switching (QMS) | A feature introduced with HDMI 2.1 that enables uninterrupted transitions between media of different frame rates from the same source, by running them at a constant refresh rate. For example, switching between a movie (24 fps) and special features (60 fps) on a Blu-ray Disc. However, a change of Source and/or resolution will trigger HPD de-assert and recycle, causing interruption for the user for several seconds. |
| Repeater Device | A device in the signal chain that receives then re-transmits the HDMI signal. Common examples would be an A/V receiver, Matrix Switch, or Distribution Amplifier |
| RGB | Red Green Blue. Red, Green, Blue color model. Values are assigned to each channel, then combined to make a wide variety of colors |
| Scaling | Video processing that can either decrease (downscale) or increase (upscale) resolution. |
| Sink device | A device at the end of an HDMI signal chain which receives an AV signal, most typically a video display device. |
| Source device | A device that provides an HDMI signal such as a Blu-ray player, streaming device, or STB |
| Standard Dynamic Range (SDR) | A retrospective reference now used to describe pre-HDR video systems. SDR systems commonly use Gamma to describe the EOTF. |
| STB | Set Top Box. A video source that is used to receive and decode Cable TV or Satellite TV services |
| SDVoE | Software-Defined Video over Ethernet; this refers to an AVoIP protocol that utilizes off-the-shelf ethernet switches. |
| Secondary color(s) | Cyan, Magenta, Yellow. The secondary colors are the products of combining the three primary colors Red, Green, and Blue with each other. Green mixed with Red produces Yellow, Blue mixed with Green produces Cyan, and Blue mixed with Red produces Magenta |
| Sharpness (TV control) | an adjustment found in most displays that when increased adds artificial edges to objects in the image. Also known as Edge Enhancement |
| SIA | Security Industry Association is a trade organization for security professionals. |
| SMPTE 2084 | SMPTE standard which defines the HDR electro-optical transfer function (EOTF) for mastering reference displays with static metadata. Also referred to as Perceptual Quantizer (PQ) curve, and ST 2084. |
| Spectroradiometer | A type of light meter that measures the amplitude and frequency of light. Commonly used when measuring and/or calibrating a display |
| sRGB | a color space that HP and Microsoft created cooperatively in 1996 to use on monitors, printers, and the Internet. Very similar to BT.709 |
| Technicolor HDR | A joint proposal from Philips and Technicolor for a Single Layer (SL) solution to HDR with SDR backwards compatibility, for both production environments and live broadcasts. Current Technicolor versions are: |
| SL-HDR1. HDR that is fully backwards with SDR in one combined signal. | |
| SL-HDR2. Adds dynamic metadata, similar to Dolby Vision and HDR10+. | |
| SL-HDR3. Deploys HLG as a base and adds dynamic metadata. | |
| Test Equipment | An instrument or instruments used to analyze the behavior of a Source, Sink, or Repeater device in isolation, or to emulate a Source, Sink, or Repeater device for the purpose of debugging an installed system by process of elimination. |
| Tone Mapping | is a technique used in image processing to map one set of colors to another to approximate the appearance of high-dynamic-range images on a display that has a more limited dynamic range. An example would be showing 4000nit content on an 800nit display |
| Transition Minimized Differential Signaling (TMDS) | The baseline technology for transmitting high-speed serial data on the main data channels in HDMI. TMDS supports aggregate data rates up to 10.2 Gbps (HDMI 1.4b) and 18 Gbps (HDMI 2.x). Note that HDMI 2.1 introduces an alternative technology, which supports aggregate data rates up to 48Gbps (see FRL). |
| Tristimulus Colorimeter | Used to measure and/or calibrate a display, this is a type of light meter that typically uses gel or glass filters to interpolate the color and intensity of light. tristimulus (three-filtered) device used in display calibration that use a red, green, and blue gel or glass filter. These types of meters are designed to emulate the response of the human eye to light and color. |
| UI | User interface. how humans interact with computer systems or other electronic devices such as a TV or Smartphone |
| Ultra HD | Moniker used to describe Ultra High Definition video formats. Variants include 1.78:1 aspect ratio formats 4K (3840x2160 active pixels) and 8K (7680x4320), and their respective 2.37:1 aspect ratio equivalents: 5K (5120x2160) and 10K (10240x4320). Referred to herein as UHD with variant suffix. |
| USB | Universal Serial Bus is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply between personal computers and their peripheral devices such as keyboards, pointer devices, webcams, etc |
| USB-A | A standard USB connection type. Supports all versions of USB. Only can connect one way. This is done by design in order to prevent damage |
| USB-B | A standard USB connection type. Almost square in shape. Used commonly on printers and other devices |
| USB-C | A standard USB connection type. Used on newer devices such as smartphones, tablets, and laptops. The orientation of the connector does not matter when being plugged in |
| USB 3.0 | the latest and fastest version of USB. Released November of 2008 supports up to 5gbps. Indicated by a blue connector on USB A devices |
| USB 4.0 | Announced in March 2019. USB 4.0 will be able to support 40gbps |
| USB extension | a cable consisting of a male USB connector on one end and a female USB connector on the opposite end. Used to make a USB cable longer when needed. Due to bandwidth limitations this is not recommended for USB 1.0 devices |
| USB extension (passive) | A USB extension cable that does not use power to extend the signal. The most affordable type of extension. Only reliable for about 15 feet |
| USB extension (active) | A USB extension cable that uses power to extend the USB signal. Can be used reliably for up to about 100ft. Power is supplied by an external power supply or within the cable itself by using the power that already exists within the protocol |
| USAV Group | United States AV |
| VAR | Value-Added Reseller |
| Variable Refresh Rate (VRR) | HDMI 2.1 feature that enables a Source such as a gaming console to send each frame of video as soon as it is ready. The display refresh rate is then synchronized to this (for example, swing between 40-120 fps), delivering better performance than a fixed linear rate (for example, 60 fps). |
| Video Format | An established operating mode with fixed horizontal and vertical picture resolution, picture and pixel aspect ratios, horizontal and vertical timing, frame rate, raster scanning method, pixel sampling method, color space and components, component depth, and code range. |
| Video Timing | The horizontal-vertical timing and frame rate aspects of a Video Format. |
| Video Noise | any distortion, artifact, or random pixilation in an image |
| VP9 | (Developed by Google) one of many standards of video compression. Competitor to H.265 and used by Youtube (as of June 2018). VP9 is customized for video resolutions greater than 1080p (such as UHD) and also enables lossless compression. The VP9 format supports the following color spaces: Rec. 601, Rec. 709, Rec. 2020, and sRGB. VP9 supports HDR video using Hybrid Log-Gamma (HLG) and Perceptual Quantizer (PQ) |
| VR | Virtual Reality |
| VSADB | Vendor-Specific Audio Data Block. An extension of the Enhanced Extended Display Identification Data (E-EDID) data structure that indicates the audio capabilities of a connected HDMI device. |
| VSVDB | Vendor-Specific Video Data Block. An extension of the Enhanced Extended Display Identification Data (E-EDID) data structure, which indicates the video capabilities of a connected HDMI device. |
| VSIF | Vendor-Specific InfoFrame data that is communicated between devices that verifies a specific feature or compatibility with a format such as Dolby Vision. |
| White Balance | The mix of the red, green, and blue signals to produce a shade of white. |
| Wide Color Gamut (WCG) | An increase in colors compared to BT.709. This includes the color gamut defined in DCI-P3 or BT.2020. |
