|
Color Frame Sequence
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video Engineering
Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual 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, 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 broadcasts, magnetic tape, optical discs, computer files, and network streaming. Etymology The word ''video'' comes from the Latin verb ''video,'' meaning to see or ''videre''. And as a noun, "that which is displayed on a (television) screen," History Analog video Video developed from facsimile systems developed in the mid-19th century. Early mechanical video scanners, such as the Nipkow disk, were patented as early as 1884, however, it took several decades b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field Dominance
{{Short description, Interlaced video signal variations 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 numbe ... [...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, usually at 24, 30, or 60 frames per second. Digital video has many advantages such as easy copying, multicasting, sharing and storage. Digital video was first introduced commercially in 1986 with the D1 (Sony), Sony D1 format, which recorded an uncompressed standard-definition component video signal in digital form. In addition to uncompressed formats, popular Data compression, compressed digital video formats today include H.264 and MPEG-4. 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 contra ... [...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 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 mai ... [...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 such as character generators and video cameras found in television studios and post-production facilities. Time base correction counteracts errors by buffering the video signal as it comes off the videotape at an unsteady rate, and releasing it after a delay at a steady rate. A sync generator provides the timing reference for all devices in the system. By adjusting the delay using a waveform monitor, the corrected signal can be made to match the timing of the other devices in the system. If all of the devices in a system are adjusted so their signals meet the video switcher at the same time and at the same rate, the signals can be mixed. Though external TBCs are often use ... [...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 ''bin ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field (video)
In video, a field is one of the many still images displayed sequentially to create the impression of motion on the screen. Normally, two fields comprise one video frame in what is known as 2:1 interlacing. 3:1, 4:1 and 5:1 interlacing also exist. When the fields are displayed on a video monitor, they are "interlaced" so 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. Sometimes in interlaced video, a field is called a frame, which can lead to confusion. To increase the resolution of video images, new schemes have been creat ... [...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 a 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 specialized, 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 linea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SECAM
SECAM, also written SÉCAM (, ''Séquentiel de couleur à mémoire'', French for ''sequential colour memory''), is an analog color television system that was used in France, Russia and some other countries or territories of Europe and Africa. It was one of three major analog color television standards, the others being PAL and NTSC. Like PAL, a SECAM picture is also made up of 625 interlaced lines and is displayed at a rate of 25 frames per second (except SECAM-M). However, due to the way SECAM processes color information, it is not compatible with the PAL video format standard. SECAM video is composite video; 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 have either converted to DVB, Digital Video Broadcasting (DVB), the new pan-European standard for digital television, or are currently in the Digital television transition, process of conversion. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
