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Color Framing
In video engineering, color framing refers to the color frame sequence of fields in a composite video signal through which the video frame timing and chrominance subcarrier signal timing—in particular, that of the color burst -- cycle through all possible phase relationships. The exact nature of the color frame sequence depends on the video standard being used. In the case of the three main composite video standards, PAL video has an 8-field (4 frame) color frame sequence, and NTSC and SECAM both have 4-field (2 frame) color frame sequences. Preserving the color framing sequence of video across edits and between channels in video effects was an important issue in early analog composite videotape editing systems, as cuts between different color sequences would cause jumps in subcarrier phase, and mixing two signals of different field dominance would result in color artifacts on the part of the signal that was not in sync with the output color frame sequence. To help prevent thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video Engineering
Video is an Electronics, electronic medium for the recording, copying, playback, broadcasting, and display of moving picture, moving image, visual Media (communication), media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems which, in turn, were replaced by flat panel displays of several types. Video systems vary in display resolution, Display aspect ratio, aspect ratio, refresh rate, color capabilities and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcast, magnetic tape, optical discs, Video file format, computer files, and Streaming media, network streaming. History Analog video Video technology was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) television systems, but several new technologies for video display devices have since been invented. Video was originally excl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field Dominance
In video engineering, field dominance refers to the choice of which field of an interlaced video signal is chosen as the point at which video edits or switches occur. There are two main choices for field dominance: odd or even. With odd field dominance the edit or switch occurs at the start of the odd field. With even field dominance the edit or switch occurs at the start of the even field (some equipment, such as vision mixers or switchers allow the field dominance to be set to 'none' which means the switch will occur on the next field boundary after the switch has been pressed). Interlacing divides the frame into two fields, each containing half the number of lines. Each field is scanned in 1/60 second under the 525-line system (or 480i – often incorrectly referred to as NTSC) or 1/50 of a second under the 625-line system (or 576i – often incorrectly referred to as PAL). With interlaced systems there are an odd number of lines in each frame. This means that there is a half lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field Dominance
In video engineering, field dominance refers to the choice of which field of an interlaced video signal is chosen as the point at which video edits or switches occur. There are two main choices for field dominance: odd or even. With odd field dominance the edit or switch occurs at the start of the odd field. With even field dominance the edit or switch occurs at the start of the even field (some equipment, such as vision mixers or switchers allow the field dominance to be set to 'none' which means the switch will occur on the next field boundary after the switch has been pressed). Interlacing divides the frame into two fields, each containing half the number of lines. Each field is scanned in 1/60 second under the 525-line system (or 480i – often incorrectly referred to as NTSC) or 1/50 of a second under the 625-line system (or 576i – often incorrectly referred to as PAL). With interlaced systems there are an odd number of lines in each frame. This means that there is a half lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Video
Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data. This is in contrast to analog video, which represents moving visual images in the form of analog signals. Digital video comprises a series of digital images displayed in rapid succession. Digital video is audio and video mixed together to make a production. the data gathered used to create a video, rather than a series of photos put together. Digital video have many advantages such as easy copying, multicasting, easy sharing and storage. Video recorded on tape is used on a computer on media player. Digital video is made of images displayed rapidly frequencies of 15, 24,30, and 60 frames per second. 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. In addition to uncompressed formats, popular compressed digital video formats today include H.264 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Component Video
Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Component video can be contrasted with '' composite video'' in which all the video information is combined into a single signal that is used in analog television. Like composite, component-video cables do not carry audio and are often paired with audio cables. When used without any other qualifications, the term ''component video'' usually refers to analog component video with sync on luma (Y) found on analog high-definition televisions and associated equipment from the 1990s through the 2000s when they were largely replaced with HDMI and other all-digital standards. Component video cables and their RCA jack connectors on equipment are normally color-coded red, green and blue, although the signal is not in RGB. YPbPr component video can be los ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame Store
A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent. Frame and FRAME may also refer to: Physical objects In building construction *Framing (construction), a building term known as light frame construction *Framer, a carpenter who assembles major structural elements in constructing a building *A-frame, a basic structure designed to bear a load in a lightweight economical manner **A-frame house, a house following the same principle *Door frame or window frame, fixed structures to which the hinges of doors or windows are attached *Frame and panel, a method of woodworking *Space frame, a method of construction using lightweight or light materials *Timber framing, a method of building for creating framed structures of heavy timber or willow wood In vehicles *Frame (aircraft), structural rings in an aircraft fuselage *Frame (nautical), the skeleton of a boat *Bicycle frame, the main c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timebase Corrector
Time base correction (TBC) is a technique to reduce or eliminate errors caused by mechanical instability present in analog recordings on mechanical media. Without time base correction, a signal from a videotape recorder (VTR) or videocassette recorder (VCR) cannot be mixed with other, more time-stable devices found in television studios and post-production facilities. Most broadcast quality VCRs have simple time base correctors built in though external TBCs are often used. Some high-end domestic analog video recorders and camcorders also include a TBC circuit, which typically can be switched off if required. Time base correction counteracts errors by buffering the video signal as it comes off the videotape at an unsteady rate, and releasing it at a steady rate. TBCs also allow a variable delay in the video stream. By adjusting the rate and delay using a waveform monitor and a vectorscope, the corrected signal can now match the timing of the other devices in the system. If a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SMPTE Time Code
SMPTE timecode ( or ) is a set of cooperating standards to label individual frames of video or film with a timecode. The system is defined by the Society of Motion Picture and Television Engineers in the SMPTE 12M specification. SMPTE revised the standard in 2008, turning it into a two-part document: SMPTE 12M-1 and SMPTE 12M-2, including new explanations and clarifications. Timecodes are added to film, video or audio material, and have also been adapted to synchronize music and theatrical production. They provide a time reference for editing, synchronization and identification. Timecode is a form of media metadata. The invention of timecode made modern videotape editing possible and led eventually to the creation of non-linear editing systems. Basic concepts SMPTE timecode is presented in ''hour:minute:second:frame'' format and is typically represented in 32 bits using binary-coded decimal. There are also ''drop-frame'' and ''color framing'' flags and three extra ''binary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subcarrier
A subcarrier is a sideband of a radio frequency carrier wave, which is modulated to send additional information. Examples include the provision of colour in a black and white television system or the provision of stereo in a monophonic radio broadcast. There is no physical difference between a carrier and a subcarrier; the "sub" implies that it has been derived from a carrier, which has been amplitude modulated by a steady signal and has a constant frequency relation to it. FM stereo Stereo broadcasting is made possible by using a subcarrier on FM radio stations, which takes the left channel and "subtracts" the right channel from it — essentially by hooking up the right-channel wires backward (reversing polarity) and then joining left and reversed-right. The result is modulated with suppressed carrier AM, more correctly called sum and difference modulation or SDM, at 38 kHz in the FM signal, which is joined at 2% modulation with the mono left+right audio (which ran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field (video)
In video, a field is one of the many still images which are displayed sequentially to create the impression of motion on the screen. Two fields comprise one video frame. When the fields are displayed on a video monitor they are "interlaced" so that the content of one field will be used on all of the odd-numbered lines on the screen and the other field will be displayed on the even lines. Converting fields to a still frame image requires a process called deinterlacing, in which the missing lines are duplicated or interpolated to recreate the information that would have been contained in the discarded field. Since each field contains only half of the information of a full frame, however, deinterlaced images do not have the resolution of a full frame. In order to increase the resolution of video images, therefore, new schemes have been created that capture full-frame images for each frame. Video composed of such frames is called progressive scan video. Video shot with a standard vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Videotape Editing
Linear video editing is a video editing post-production process of selecting, arranging and modifying images and sound in a predetermined, ordered sequence. Regardless of whether it was captured by a video camera, tapeless camcorder, or recorded in a television studio on a video tape recorder (VTR) the content must be accessed sequentially. For the most part video editing software has replaced linear editing. In the past, film editing was done in linear fashion, where film reels were literally cut into long strips divided by takes and scenes, and then glued or taped back together to create a logical sequence of film. Linear video editing is more time consuming and highly specialised and tedious work. Still, it is relevant today because of these reasons: * The method is simple and inexpensive. * Mandatory for some jobs: for example if only two sections of video clips are to be joined together in sequence it is often the quickest and easiest way. * If video editors learn linear editin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SECAM
SECAM, also written SÉCAM (, ''Séquentiel de couleur à mémoire'', French for ''color sequential with memory''), is an analog color television system that was used in France, some parts of Europe and Africa, and Russia. It was one of three major analog color television standards, the others being PAL and NTSC. This page primarily discusses the SECAM colour encoding system. The articles on broadcast television systems and analog television further describe frame rates, image resolution, and audio modulation. SECAM video is composite video because the luminance (luma, monochrome image) and chrominance (chroma, color applied to the monochrome image) are transmitted together as one signal. All the countries using SECAM are currently in the process of conversion, or have already converted to Digital Video Broadcasting (DVB), the new pan-European standard for digital television. SECAM remained a major standard into the 2000s. History Development of SECAM predates PAL, and be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
