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62-416: A playlist is a list of video or audio files that can be played back on a media player , either sequentially or in a shuffled order. In its most general form, an audio playlist is simply a list of songs that can be played once or in a loop . The term has several specialized meanings in the realms of television broadcasting , radio broadcasting and personal computers . A video playlist can also be

124-488: A constant bitrate (CBR). This CBR video is suitable for real-time, non-buffered, fixed bandwidth video streaming (e.g. in videoconferencing). Since not all frames can be compressed at the same level, because quality is more severely impacted for scenes of high complexity, some algorithms try to constantly adjust the BPP. They keep the BPP high while compressing complex scenes and low for less demanding scenes. This way, it provides

186-670: A software MP3 player for Windows , Android , or macOS , the desired tunes are typically dragged and dropped from the user's music library into the player's "edit or create playlist" window and saved. The idea of automatically generating music playlists from annotated databases was pioneered by François Pachet and Pierre Roy. Constraint satisfaction techniques were developed to create playlists that satisfy arbitrary "sequence constraints", such as continuity, diversity, similarity, etc. Since, many other techniques were proposed, such as case-based reasoning . Notable file formats used for playlists include: Digital video Digital video

248-479: A "flat" picture can be transformed so as to give an illusion of depth when viewed through anaglyph glasses (usually red-cyan). An image viewed through anaglyph glasses appears to have both protruding and deeply embedded objects in it, at the expense of somewhat distorted colors. The method itself is old enough , dating back to the mid-19th century, but it is only with recent advances in computer technology that it has become possible to apply this kind of transformation to

310-439: A D2 VCR. This made it a perfect fit for the majority of television facilities at the time. D2 was a successful format in the television broadcast industry throughout the late '80s and the '90s. D2 was also widely used in that era as the master tape format for mastering laserdiscs . D1 & D2 would eventually be replaced by cheaper systems using video compression, most notably Sony's Digital Betacam , that were introduced into

372-740: A Nobel Prize for his work in physics. Following the commercialization of CCD sensors during the late 1970s to early 1980s, the entertainment industry slowly began transitioning to digital imaging and digital video from analog video over the next two decades. The CCD was followed by the CMOS active-pixel sensor ( CMOS sensor ), developed in the 1990s. Major films shot on digital video overtook those shot on film in 2013. Since 2016 over 90% of major films were shot on digital video. As of 2017 , 92% of films are shot on digital. Only 24 major films released in 2018 were shot on 35mm. Today, cameras from companies like Sony , Panasonic , JVC and Canon offer

434-426: A collection of objects composed of 3D vertices and textures, much like in any modern video game, to achieve special effects. Tedious and costly, this method is only used in a small fraction of movies produced worldwide, while most movies remain in the form of traditional 2D images. It is, however, possible to give an otherwise two-dimensional picture the appearance of depth. Using a technique known as anaglyph processing

496-399: A full frame. The second half contains only the even-numbered lines. These halves are referred to individually as fields . Two consecutive fields compose a full frame. If an interlaced video has a frame rate of 30 frames per second the field rate is 60 fields per second, though both part of interlaced video, frames per second and fields per second are separate numbers. By definition, bit rate

558-509: A limited list of songs to be played. The term would go on to refer to the entire catalog of songs that a given radio station (of any format) would draw from. Additionally, the term was used to refer to an ordered list of songs played during a given time period. Playlists are often adjusted based on time of day, known as dayparting . Cable TV and broadcast TV news channels often use video playlists to rerun prerecorded news stories. A given news story might initially be shown live and then placed into

620-469: A list of recorded titles on a digital video disk (DVD). On the internet, a playlist can be a list of chapters in a movie serial ; for example, Flash Gordon in the Planet Mongo is available on YouTube as a playlist of thirteen consecutive video chapters. The term originally came about in the early days of Top 40 radio formats in the 1950s when stations would devise (and, eventually, publish)

682-527: A modified 1-inch type B videotape transport and recorded an early form of CCIR 601 digital video. Ampex's prototype digital video recorder used a modified 2-inch quadruplex videotape VTR (an Ampex AVR-3) fitted with custom digital video electronics and a special octaplex 8-head headwheel (regular analog 2" quad machines only used 4 heads). Like standard 2" quad, the audio on the Ampex prototype digital machine, nicknamed Annie by its developers, still recorded

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744-475: A playlist to be shown over and over again at a later time. News channel broadcasting is a combination of live and pre-recorded programming. The prerecorded clips are usually run from a playlist. As music storage and playback using personal computers became common, the term "playlist" was adopted by various media player software programs intended to organize and control music on a PC. Such playlists may be defined, stored, and selected to run either in sequence or if

806-408: A random playlist function is selected, in a random order. Playlists' uses include allowing a particular desired musical atmosphere to be created and maintained without constant user interaction or allowing a variety of different styles of music to be played, again without maintenance. Several computer playlist formats for multimedia players, such as PLS , can pass a playlist or URL to the player. In

868-797: A seek bar, a timer with the current and total playback time, playback controls (play, pause, previous, next, stop), playlists, a "repeat" mode, and a "shuffle" (or "random") mode for curiosity and to facilitate searching long timelines of files. Different media players have different goals and feature sets. Video players are a group of media players that have their features geared more towards playing digital video . For example, Windows DVD Player exclusively plays DVD-Video discs and nothing else. Media Player Classic can play individual audio and video files but many of its features such as color correction, picture sharpening, zooming, set of hotkeys , DVB support and subtitle support are only useful for video material such as films and cartoons. Audio players , on

930-401: A series of digital images displayed in rapid succession. In the context of video, these images are called frames . The rate at which frames are displayed is known as the frame rate and is measured in frames per second . Every frame is a digital image and so comprises a formation of pixels . The color of a pixel is represented by a fixed number of bits of that color where the information of

992-754: A series of frames in a motion picture reasonably fast or even in real-time, i.e. as the video is being played back. Several implementations exist in the form of 3D video players that render conventional 2D video in anaglyph 3D, as well as in the form of 3D video converters that transform video into stereoscopic anaglyph and transcode it for playback with regular software or hardware video players. Well known examples of media player software include Windows Media Player , VLC media player , iTunes , Winamp , Media Player Classic , MediaMonkey , foobar2000 , AIMP , MusicBee and JRiver Media Center . Most of these also include music library managers. Although media players are often multi-media, they can be primarily designed for

1054-512: A specific media. For example, Media Player Classic and VLC media player are video-focused while Winamp and iTunes are music-focused, despite all of them supporting both types of media. A home theater PC or media center computer is a convergence device that combines some or all the capabilities of a personal computer with a software application that supports video, photo, audio playback, and sometimes video recording functionality. Although computers with some of these capabilities were available from

1116-486: A tooltip bubble previewing footage at the position hovered over with the mouse cursor. A preview tooltip for the seek bar has been implemented on few smartphones through a stylus or a self-capacitive touch screen able to detect a floating finger. Such include the Samsung Galaxy S4, S5 (finger), Note 2, Note 4 (stylus), and Note 3 (both). Streaming media players may indicate buffered segments of

1178-448: A variety of choices for shooting high-definition video. At the high-end of the market, there has been an emergence of cameras aimed specifically at the digital cinema market. These cameras from Sony , Vision Research , Arri , Blackmagic Design , Panavision , Grass Valley and Red offer resolution and dynamic range that exceeds that of traditional video cameras, which are designed for the limited needs of broadcast television . In

1240-402: Is a measurement of the rate of information content from the digital video stream. In the case of uncompressed video, bit rate corresponds directly to the quality of the video because bit rate is proportional to every property that affects the video quality . Bit rate is an important property when transmitting video because the transmission link must be capable of supporting that bit rate. Bit rate

1302-690: Is also carried using UDP - IP over Ethernet . Two approaches exist for this: Other methods of carrying video over IP Media player (software) Media player software is a type of application software for playing multimedia computer files like audio and video files. Media players commonly display standard media control icons known from physical devices such as tape recorders and CD players , such as play (  [REDACTED]  ), pause (  [REDACTED]  ), fastforward (⏩️), rewind (⏪), and stop (  [REDACTED]  ) buttons. In addition, they generally have progress bars (or "playback bars"), which are sliders to locate

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1364-424: Is also important when dealing with the storage of video because, as shown above, the video size is proportional to the bit rate and the duration. Video compression is used to greatly reduce the bit rate while having little effect on quality. Bits per pixel (BPP) is a measure of the efficiency of compression. A true-color video with no compression at all may have a BPP of 24 bits/pixel. Chroma subsampling can reduce

1426-739: Is available on the Internet. Pandora is one of the few music services that is free (no subscription required) to users. The user can select genres that are played back at random on Pandora's playlists. A celebrity playlist is a list of songs prepared by a celebrity and represented in popular publications and on the radio as such. On video hosting service websites such as YouTube and Vimeo , users can make playlists of select videos from themselves or other users for topical purposes; paid accounts can upgrade playlists of their own videos to "shows". Most media players , such as Winamp , can easily create custom playlists from one's media library. For example, in

1488-438: Is determined by the frame size, color depth and frame rate. Each pixel consumes a number of bits determined by the color depth. The data required to represent a frame of data is determined by multiplying by the number of pixels in the image. The bandwidth is determined by multiplying the storage requirement for a frame by the frame rate. The overall storage requirements for a program can then be determined by multiplying bandwidth by

1550-478: Is increasingly common in schools, with students and teachers taking an interest in learning how to use it in relevant ways. Digital video also has healthcare applications, allowing doctors to track infant heart rates and oxygen levels. In addition, the switch from analog to digital video impacted media in various ways, such as in how businesses use cameras for surveillance. Closed circuit television (CCTV) switched to using digital video recorders (DVR), presenting

1612-467: Is used due to its reduction of data consumption by factors of 20 to 200. Note that it is not necessary that all frames are equally compressed by the same percentage. Instead, consider the average factor of compression for all the frames taken together. Purpose-built digital video interfaces General-purpose interfaces use to carry digital video The following interface has been designed for carrying MPEG -Transport compressed video: Compressed video

1674-509: The Internet to end users who watch content on a personal computer or mobile device screen or a digital smart TV . Today, digital video content such as TV shows and movies also includes a digital audio soundtrack. The basis for digital video cameras is metal–oxide–semiconductor (MOS) image sensors . The first practical semiconductor image sensor was the charge-coupled device (CCD), invented in 1969 by Willard S. Boyle, who won

1736-707: The bandwidth needed for a high-definition video signal (with HDV and AVCHD , as well as several professional formats such as XDCAM , all using less bandwidth than a standard definition analog signal). These savings have increased the number of channels available on cable television and direct broadcast satellite systems, created opportunities for spectrum reallocation of terrestrial television broadcast frequencies, and made tapeless camcorders based on flash memory possible, among other innovations and efficiencies. Culturally, digital video has allowed video and film to become widely available and popular, beneficial to entertainment, education, and research. Digital video

1798-453: The 1970s, pulse-code modulation (PCM) induced the birth of digital video coding , demanding high bit rates of 45-140 Mbit/s for standard-definition (SD) content. By the 1980s, the discrete cosine transform (DCT) became the standard for digital video compression . The first digital video coding standard was H.120 , created by the (International Telegraph and Telephone Consultative Committee) or CCITT (now ITU-T) in 1984. H.120

1860-442: The BPP to 16 or 12 bits/pixel. Applying JPEG compression on every frame can reduce the BPP to 8 or even 1 bits/pixel. Applying video compression algorithms like MPEG1 , MPEG2 or MPEG4 allows for fractional BPP values to exist. BPP represents the average bits per pixel. There are compression algorithms that keep the BPP almost constant throughout the entire duration of the video. In this case, we also get video output with

1922-499: The ability to adjust appearance and acoustics during playback using effects such as mirroring, rotating, cropping, cloning, adjusting colours, deinterlacing , and equalizing and visualizing audio . Easter eggs may be featured, such as a puzzle game on VLC Media Player . Still snapshots may be extracted directly from a video frame or captured through a screenshot, the former of which is preferred since it preserves videos' original dimensions (height and width). Video players may show

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1984-531: The audio in analog as linear tracks on the tape. None of these machines from these manufacturers were ever marketed commercially. Digital video was first introduced commercially in 1986 with the Sony D1 format, which recorded an uncompressed standard definition component video signal in digital form. Component video connections required 3 cables, but most television facilities were wired for composite NTSC or PAL video using one cable. Due to this incompatibility

2046-460: The availability of inexpensive, high-performance computers . It was not until the 1990s that digital TV became a real possibility. Digital television was previously not practically feasible due to the impractically high bandwidth requirements of uncompressed video , requiring around 200   Mbit/s for a standard-definition television (SDTV) signal, and over 1   Gbit/s for high-definition television (HDTV). Digital video comprises

2108-562: The best quality at the smallest average bit rate (and the smallest file size, accordingly). This method produces a variable bitrate because it tracks the variations of the BPP. Standard film stocks typically record at 24 frames per second. For video, there are two frame rate standards: NTSC , at 30/1.001 (about 29.97) frames per second (about 59.94 fields per second), and PAL , 25 frames per second (50 fields per second). Digital video cameras come in two different image capture formats: interlaced and progressive scan . Interlaced cameras record

2170-495: The case of radio stations it can also link many audio players directly to the station's live streaming audio, bypassing any need for a web browser. (In that case, the playlist file is typically downloaded from the station's live streaming web page, if offered. The files are similar to Internet shortcut files in appearance and internal structure, except used by media players rather than web browsers.) Some Internet streaming services , such as Spotify , Amazon Music , 8tracks , and

2232-403: The color is stored within the image. For example, 8-bit captures 256 levels per channel, and 10-bit captures 1,024 levels per channel. The more bits, the more subtle variations of colors can be reproduced. This is called the color depth , or bit depth, of the video. In interlaced video each frame is composed of two halves of an image. The first half contains only the odd-numbered lines of

2294-637: The cost of the recorder, D1 was used primarily by large television networks and other component-video capable video studios. In 1988, Sony and Ampex co-developed and released the D2 digital videocassette format, which recorded video digitally without compression in ITU-601 format, much like D1. In comparison, D2 had the major difference of encoding the video in composite form to the NTSC standard, thereby only requiring single-cable composite video connections to and from

2356-664: The current position in the duration of the media file. Mainstream operating systems have at least one default media player. For example, Windows comes with Windows Media Player , Microsoft Movies & TV and Groove Music , while macOS comes with QuickTime Player and Music . Linux distributions come with different media players, such as SMPlayer , Amarok , Audacious , Banshee , MPlayer , mpv , Rhythmbox , Totem , VLC media player , and xine . Android comes with YouTube Music for audio and Google Photos for video, and smartphone vendors such as Samsung may bundle custom software. The basic feature set of media players are

2418-406: The defunct Playlist.com and Webjay , allow users to categorize, edit, and listen to playlists online. Other sites focus on playlist creation aided by personalized song recommendations, ratings, and reviews. On certain sites, users create and share annotated playlists, giving visitors the option to read contextual information or reviewer comments about each song while listening. Some sites only allow

2480-436: The duration of the program. These calculations are accurate for uncompressed video, but due to the relatively high bit rate of uncompressed video, video compression is extensively used. In the case of compressed video, each frame requires only a small percentage of the original bits. This reduces the data or bandwidth consumption by a factor of 5 to 12 times when using lossless compression , but more commonly, lossy compression

2542-414: The early 1980s, video production equipment that was digital in its internal workings was introduced. These included time base correctors (TBC) and digital video effects (DVE) units. They operated by taking a standard analog composite video input and digitizing it internally. This made it easier to either correct or enhance the video signal, as in the case of a TBC, or to manipulate and add effects to

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2604-569: The expensive and time-consuming chemical processing required by film. Network transfer of digital video makes physical deliveries of tapes and film reels unnecessary. Digital television (including higher quality HDTV ) was introduced in most developed countries in early 2000s. Today, digital video is used in modern mobile phones and video conferencing systems. Digital video is used for Internet distribution of media, including streaming video and peer-to-peer movie distribution. Many types of video compression exist for serving digital video over

2666-426: The feature set of Media Player Classic and MediaMonkey combined. By default, videos are played with fully visible field of view while filling at least either width or height of the viewport to appear as large as possible. Options to change the video's scaling and aspect ratio may include filling the viewport through either stretching or cropping, and "100% view" where each pixel of the video covers exactly one pixel on

2728-425: The image in alternating sets of lines: the odd-numbered lines are scanned, and then the even-numbered lines are scanned, then the odd-numbered lines are scanned again, and so on. One set of odd or even lines is referred to as a field , and a consecutive pairing of two fields of opposite parity is called a frame . Progressive scan cameras record all lines in each frame as a single unit. Thus, interlaced video captures

2790-694: The internet and on optical disks. The file sizes of digital video used for professional editing are generally not practical for these purposes, and the video requires further compression with codecs to be used for recreational purposes. As of 2017 , the highest image resolution demonstrated for digital video generation is 132.7 megapixels (15360 x 8640 pixels). The highest speed is attained in industrial and scientific high-speed cameras that are capable of filming 1024x1024 video at up to 1 million frames per second for brief periods of recording. Live digital video consumes bandwidth. Recorded digital video consumes data storage. The amount of bandwidth or storage required

2852-498: The introduction of the DV tape format allowing recordings in the format to be transferred directly to digital video files using a FireWire port on an editing computer. This simplified the process, allowing non-linear editing systems (NLE) to be deployed cheaply and widely on desktop computers with no external playback or recording equipment needed. The widespread adoption of digital video and accompanying compression formats has reduced

2914-509: The issue of how to store recordings for evidence collection. Today, digital video is able to be compressed in order to save storage space. Digital television (DTV) is the production and transmission of digital video from networks to consumers. This technique uses digital encoding instead of analog signals used prior to the 1950s. As compared to analog methods, DTV is faster and provides more capabilities and options for data to be transmitted and shared. Digital television's roots are tied to

2976-416: The majority of patents belonging to Samsung Electronics , GE , NTT and JVC Kenwood . It is currently being challenged by the aiming-to-be-freely-licensed AV1 format. As of 2019 , AVC is by far the most commonly used format for the recording, compression and distribution of video content, used by 91% of video developers, followed by HEVC which is used by 43% of developers. Starting in the late 1970s to

3038-399: The media in the seek bar. 3D video players are used to play 2D video in 3D format. A high-quality three-dimensional video presentation requires that each frame of a motion picture be embedded with information on the depth of objects present in the scene. This process involves shooting the video with special equipment from two distinct perspectives or modeling and rendering each frame as

3100-436: The network's television studios . Other examples of digital video formats utilizing compression were Ampex's DCT (the first to employ such when introduced in 1992), the industry-standard DV and MiniDV and its professional variations, Sony's DVCAM and Panasonic's DVCPRO , and Betacam SX , a lower-cost variant of Digital Betacam using MPEG-2 compression. One of the first digital video products to run on personal computers

3162-554: The other hand, specialize in digital audio . For example, AIMP exclusively plays audio formats. MediaMonkey can play both audio and video formats, but many of its features including media library, lyric discovery, music visualization , online radio, audiobook indexing, and tag editing are geared toward consumption of audio material; watching video files on it can be a trying feat. General-purpose media players also do exist. For example, Windows Media Player has exclusive features for both audio and video material, although it cannot match

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3224-410: The scene motion twice as often as progressive video does for the same frame rate. Progressive scan generally produces a slightly sharper image, however, motion may not be as smooth as interlaced video. Digital video can be copied with no generation loss; which degrades quality in analog systems. However, a change in parameters like frame size, or a change of the digital format can decrease the quality of

3286-400: The screen. Zooming into the field of view during playback may be implemented through a slider on any screen or with pinch zoom on touch screens, and moving the field of view may be implemented through scrolling by dragging inside the view port or by moving a rectangle inside a miniature view of the entire field of view that denotes the magnified area. Media player software may have

3348-411: The sharing of the playlist data with the actual music being delivered by other channels (e.g., Plurn), others provide a closed catalog of content from which the playlists can be generated, and sites like imeem allow users to upload the music to central servers to be shared and accessed by any user of the site. iPods can also be used to build playlists. Pandora is another music streaming service that

3410-436: The video due to image scaling and transcoding losses. Digital video can be manipulated and edited on non-linear editing systems. Digital video has a significantly lower cost than 35 mm film. In comparison to the high cost of film stock , the digital media used for digital video recording, such as flash memory or hard disk drive is very inexpensive. Digital video also allows footage to be viewed on location without

3472-406: The video, in the case of a DVE unit. The digitized and processed video information was then converted back to standard analog video for output. Later on in the 1970s, manufacturers of professional video broadcast equipment, such as Bosch (through their Fernseh division) and Ampex developed prototype digital videotape recorders (VTR) in their research and development labs. Bosch's machine used

3534-546: Was PACo: The PICS Animation Compiler from The Company of Science & Art in Providence, RI. It was developed starting in 1990 and first shipped in May 1991. PACo could stream unlimited-length video with synchronized sound from a single file (with the .CAV file extension ) on CD-ROM. Creation required a Mac, and playback was possible on Macs, PCs, and Sun SPARCstations . QuickTime , Apple Computer 's multimedia framework,

3596-541: Was developed based on DCT compression, becoming first practical video coding standard. Since H.261, DCT compression has been adopted by all the major video coding standards that followed. MPEG-1 , developed by the Motion Picture Experts Group (MPEG), followed in 1991, and it was designed to compress VHS -quality video. It was succeeded in 1994 by MPEG-2 / H.262 , which became the standard video format for DVD and SD digital television . It

3658-782: Was first introduced commercially in 1986 with the Sony D1 format, which recorded an uncompressed standard-definition component video signal in digital form. In addition to uncompressed formats , popular compressed digital video formats today include MPEG-2 , H.264 and AV1 . Modern interconnect standards used for playback of digital video include HDMI , DisplayPort , Digital Visual Interface (DVI) and serial digital interface (SDI). Digital video can be copied and reproduced with no degradation in quality. In contrast, when analog sources are copied, they experience generation loss . Digital video can be stored on digital media such as Blu-ray Disc , on computer data storage , or streamed over

3720-418: Was followed by MPEG-4 in 1999, and then in 2003 it was followed by H.264/MPEG-4 AVC , which has become the most widely used video coding standard. The current-generation video coding format is HEVC (H.265), introduced in 2013. While AVC uses the integer DCT with 4x4 and 8x8 block sizes, HEVC uses integer DCT and DST transforms with varied block sizes between 4x4 and 32x32. HEVC is heavily patented, with

3782-481: Was not practical due to weak performance. H.120 was based on differential pulse-code modulation (DPCM), a compression algorithm that was inefficient for video coding. During the late 1980s, a number of companies began experimenting with DCT, a much more efficient form of compression for video coding. The CCITT received 14 proposals for DCT-based video compression formats, in contrast to a single proposal based on vector quantization (VQ) compression. The H.261 standard

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3844-496: Was released in June 1991. Audio Video Interleave from Microsoft followed in 1992. Initial consumer-level content creation tools were crude, requiring an analog video source to be digitized to a computer-readable format. While low-quality at first, consumer digital video increased rapidly in quality, first with the introduction of playback standards such as MPEG-1 and MPEG-2 (adopted for use in television transmission and DVD media), and

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