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 were later replaced by flat panel displays of several types.
Gamma correction or gamma is a nonlinear operation used to encode and decode luminance or tristimulus values in video or still image systems. Gamma correction is, in the simplest cases, defined by the following power-law expression:
Digital Picture Exchange (DPX) is a common file format for digital intermediate and visual effects work and is a SMPTE standard. The file format is most commonly used to represent the density of each colour channel of a scanned negative film in an uncompressed "logarithmic" image where the gamma of the original camera negative is preserved as taken by a film scanner. For this reason, DPX is the worldwide-chosen format for still frames storage in most digital intermediate post-production facilities and film labs. Other common video formats are supported as well, from video to purely digital ones, making DPX a file format suitable for almost any raster digital imaging applications. DPX provides, in fact, a great deal of flexibility in storing colour information, colour spaces and colour planes for exchange between production facilities. Multiple forms of packing and alignment are possible. The DPX specification allows for a wide variety of metadata to further clarify information stored within each file.
Digital intermediate is a motion picture finishing process which classically involves digitizing a motion picture and manipulating the color and other image characteristics.
Color grading is the process of improving the appearance of an image for presentation in different environments on different devices. Various attributes of an image such as contrast, color, saturation, detail, black level, and white point may be enhanced whether for motion pictures, videos, or still images. Color grading and color correction are often used synonymously as terms for this process and can include the generation of artistic color effects through creative blending and compositing of different images. Color grading is generally now performed in a digital process either in a controlled environment such as a color suite, or in any location where a computer can be used in dim lighting.
An image scanner—often abbreviated to just scanner—is a device that optically scans images, printed text, handwriting or an object and converts it to a digital image. Commonly used in offices are variations of the desktop flatbed scanner where the document is placed on a glass window for scanning. Hand-held scanners, where the device is moved by hand, have evolved from text scanning "wands" to 3D scanners used for industrial design, reverse engineering, test and measurement, orthotics, gaming and other applications. Mechanically driven scanners that move the document are typically used for large-format documents, where a flatbed design would be impractical.
A film recorder is a graphical output device for transferring images to photographic film from a digital source. In a typical film recorder, an image is passed from a host computer to a mechanism to expose film through a variety of methods, historically by direct photography of a high-resolution cathode ray tube (CRT) display. The exposed film can then be developed using conventional developing techniques, and displayed with a slide or motion picture projector. The use of film recorders predates the current use of digital projectors, which eliminate the time and cost involved in the intermediate step of transferring computer images to film stock, instead directly displaying the image signal from a computer. Motion picture film scanners are the opposite of film recorders, copying content from film stock to a computer system. Film recorders can be thought of as modern versions of Kinescopes.
Transcoding is the direct digital-to-digital conversion of one encoding to another, such as for movie data files, audio files, or character encoding. This is usually done in cases where a target device does not support the format or has limited storage capacity that mandates a reduced file size, or to convert incompatible or obsolete data to a better-supported or modern format.
Image resolution is the detail an image holds. The term applies to digital images, film images, and other types of images. Higher resolution means more image detail.
Film-out is the process in the computer graphics, video production and filmmaking disciplines of transferring images or animation from videotape or digital files to a traditional film print. "Film-out" is a broad term that encompasses the conversion of frame rates, color correction, as well as the actual printing, also called scannior recording.
Digital Cinema Initiatives, LLC (DCI) is a consortium of major motion picture studios, formed to establish specifications for a common systems architecture for digital cinema systems.
Photo CD is a system designed by Kodak for digitizing and saving photos onto a CD. Launched in 1991, the discs were designed to hold nearly 100 high quality images, scanned prints and slides using special proprietary encoding. Photo CDs are defined in the Beige Book and conform to the CD-ROM XA and CD-i Bridge specifications as well. They were intended to play on CD-i players, Photo CD players, and any computer with a suitable software.
A camera raw image file contains minimally processed data from the image sensor of either a digital camera, a motion picture film scanner, or other image scanner. Raw files are named so because they are not yet processed and therefore are not ready to be printed or edited with a bitmap graphics editor. Normally, the image is processed by a raw converter in a wide-gamut internal color space where precise adjustments can be made before conversion to a "positive" file format such as TIFF or JPEG for storage, printing, or further manipulation. There are dozens of raw formats in use by different manufacturers of digital image capture equipment.
A motion picture film scanner is a device used in digital filmmaking to scan original film for storage as high-resolution digital intermediate files.
A virtual telecine is a piece of video equipment that can play back data files in real time. The colorist-video operator controls the virtual telecine like a normal telecine, although without controls like focus and framing. The data files can be from a Spirit DataCine, motion picture film scanner, CGI animation computer, or an Acquisition professional video camera. The normal input data file standard is DPX. The output of data files are often used in digital intermediate post-production using a film recorder for film-out. The control room for the virtual telecine is called the color suite.
Uncompressed video is digital video that either has never been compressed or was generated by decompressing previously compressed digital video. It is commonly used by video cameras, video monitors, video recording devices, and in video processors that perform functions such as image resizing, image rotation, deinterlacing, and text and graphics overlay. It is conveyed over various types of baseband digital video interfaces, such as HDMI, DVI, DisplayPort and SDI. Standards also exist for the carriage of uncompressed video over computer networks.
Articles related to the field of motion pictures include:
Spirit DataCine is a telecine and a motion picture film scanner. This device is able to transfer 16mm and 35mm motion picture film to NTSC or PAL television standards or one of many High-definition television standards. With the data transfer option a Spirit DataCine can output DPX data files. The image pick up device is a solid state charge-coupled device. This eliminated the need for glass vacuum tube CRTs used on older telecines. The units can transfer negative film, primetime, intermediate film and print film, stock. One option is a Super 8 gate for the transfer of Super 8 mm film. With a sound pick up option, optical 16mm and 35mm sound can be reproduced, also 16mm magnetic strip sound. The unit can operate stand alone or be controlled by a scene by scene color corrector. Ken Burns created The Civil War, a short documentary film included in the DVD release, on how he used the Spirit DataCine to transfer and remaster this film. The operator of the unit is called a Colorist or Colorist Assistant. The Spirit DataCine has become the standard for high-end real-time film transfer and scanning. Over 370 units are used in post production facilities around the world. Most current film productions are transferred on Spirit DataCines for Television, Digital television, Cable television, Satellite television, Direct-to-video, DVD, Blu-ray Disc, pay-per-view, In-flight entertainment, Stock footage, Dailies, Film preservation, digital intermediate and digital cinema. The Spirit DataCine is made by DFT Digital Film Technology GmbH in Darmstadt, Germany.
Pandora International is a maker of hardware and software systems for video editing, Telecine Control and Colour Correction. Pandora was founded in 1985 By Steve Brett and Martin Greenwood, later Aine Marsland joined the team and took over the administration of the company. Pandora International devices are able to colour-correct video and 16 mm and 35 mm motion picture film in real time. Pandora International is based in Greenhithe, Kent, England.
The Academy Color Encoding System (ACES) is a color image encoding system created by hundreds of industry professionals under the auspices of the Academy of Motion Picture Arts and Sciences. ACES allows for a fully encompassing color accurate workflow, with "seamless interchange of high quality motion picture images regardless of source".
