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26-397: Standard AFD codes provide information to video devices about where in the coded picture the active video is and also the " protected area " which is the area that needs to be shown. Outside the protected area, edges at the sides or the top can be removed without the viewer missing anything significant. Video decoders and display devices can then use this information, together with knowledge of

52-471: A picture will be windowboxed on purpose. During the opening, documentary-style sequence of Rent on the DVD and Blu-ray Disc releases, the picture is windowboxed to suggest an older camera meant to present at a 4:3 aspect ratio; as the movie transitions from that segment, it then expands horizontally from a windowboxed 4:3 to a letterboxed 2.39:1 aspect ratio. Another example is in the movie Brother Bear . On

78-405: A platform that supports AFDs. In 2012, a Technology & Engineering Emmy Award was awarded for the development and deployment of Active Format Description. A widescreen 16:9 signal may be broadcast with AFD 8 or AFD 10, indicating that the entire frame includes important picture information and should not be cropped. On a 4:3 TV, this will then be shown as a 16:9 letterbox to ensure no image

104-407: A result, the quality of implementation in receivers is variable. Some receivers only respect the basic "active area" information. More fully featured receivers also support the "safe area" information, and will use this to optimise the display for the shape of the viewer's screen. Display in the compromise 14:9 letterbox format was not supported by initial British receivers, which limited the value of

130-468: A widescreen display. The windowboxing was done so that overscanning would be prevented when playing a game on a 4:3 television unit, and so that no on-screen information would be cut off. Some widescreen televisions have a horizontal stretch feature that stretches the image with minimal vertical cropping, compared to the vertical amount that normal zoom feature would crop off, but it causes far more distortion rather than normally zooming in on all four sides of

156-501: Is because the MPEG signalling can only change with a new Group of Pictures in the sequence, which is typically around every 12 frames or half a second - this was not considered accurate enough for some broadcasters who were initially switching frequently between 4:3 and 16:9. The number of Aspect Ratio Converters required in a broadcast facility is also reduced, since the content is described correctly it does not need to be resized for broadcast on

182-412: Is dependent on whether or not the issue of overscan is better solved via hardware (through the use of newer equipment, to the detriment of those with older displays) or via software (through the use of windowboxing, to the detriment of those with newer displays). At the time before widescreen televisions became popular, most video game consoles until the seventh generation were windowboxed when shown on

208-523: Is lost. Other widescreen 16:9 content (like sports coverage) may be broadcast with AFD 15, indicating that it is safe to display only the central 4:3 region. On a 4:3 TV, the image will be cropped and it will be shown full-screen. As of 2006, AFDs are only broadcast in a minority of the countries using MPEG digital television but used most notably in the UK as required by the Digital TV Group D-Book. As

234-653: Is occasionally incorrectly referred to as "Active Format Descriptor". There is no "descriptor" (descriptor has a specific meaning in ISO/IEC 13818-1, MPEG syntax). The AFD data is carried in the Video Layer of MPEG, ISO/IEC 13818-2. When carried in digital video, AFDs can be stored in the Video Index Information, in line 11 of the video. By using AFDs broadcasters can also control the timing of Aspect Ratio switches more accurately than using MPEG signalling alone. This

260-412: Is shot in such a way that the areas of interest within a frame lie within a rectangular "protected area" within the frame, with margins at top and bottom and both sides. The action safe and caption safe areas then lie within this protected area. This allows the resulting material to be cropped to any of a wide range of aspect ratios , whether wider or narrower than the shooting format, without losing

286-427: Is to be either letterbox or center-cut for their SD viewers. However, there are cases where pay-TV providers completely disregard AFD instructions and for instance, present a 4:3 picture with widescreen elements cut off to assuage user complaints about letterboxing, on standard 4:3 sets (for instance for a secondary-market station available only in standard definition on a provider on the claim that an HD signal exists for

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312-600: The AFD flags - this ratio is especially useful when watching widescreen material on smaller 4:3 sets. The line 23 data format (compatible with the analog Widescreen signaling ) allows signaling of the source (coded image) aspect ratio and the Active Format Descriptor. A concerted effort on the part of US broadcasters to broadcast AFD began in 2008 in preparation for the US DTV transition which occurred on June 12, 2009. After

338-714: The DTV transition, 4:3 versions of programming are not available directly from a large percentage of US broadcasters. Cable and satellite providers down-convert 16:9 HD feeds from these broadcasters to generate the 4:3 SD versions for their SD viewers. The most common forms of down-conversion are letterbox or center-cut (cropping off the left and right sides of the 16:9 image to fit into the 4:3 raster). Some US broadcasters transmit AFD with their HD DTV signals in order to maintain control over how SD viewers will receive their programming. With AFD included in these signals, cable and satellite providers are able to dynamically control whether HD content

364-403: The above codes and the resulting images as seen on 4:3, 16:9 and 21:9 displays. Green circles represent essential content, orange circles indicate optional image areas. Black areas are unused parts of the frame, i.e. bars. The red edge indicates the full frame. [REDACTED] Shoot and protect Shoot and protect is a technique used in video and film production, in which the material

390-423: The black borders around all four sides of the image are visible, effectively shrinking the image on those displays. Windowboxing on video also reduces the total amount of resolution the image effectively uses, but defenders of the process argue that the lost resolution is negligible. Defenders also argue that the prevalence of credit sequences being windowboxed on recent DVDs suggests a natural progression towards

416-402: The display of film or video occurs when the aspect ratio of the media is such that the letterbox effect and pillarbox effect occur simultaneously. Sometimes, by accident or design, a standard ratio image is presented in the central portion of a letterbox picture (or vice versa), resulting in a black border all around. It is generally disliked because it wastes much screen space and reduces

442-654: The display shape and user preferences, to choose a presentation mode. AFD can be used in the generation of Widescreen signaling , although MPEG alone contains enough information to generate this. AFDs are not part of the core MPEG standard; they were originally developed within the Digital TV Group in the UK and submitted to DVB as an extension, which has subsequently also been adopted by ATSC (with some changes). SMPTE has also adopted AFD for baseband SDI carriage as standard SMPTE 2016-1-2007, " Format for Active Format Description and Bar Data ". Active Format Description

468-453: The full presentation being windowboxed, just as widescreen presentations progressed. However, letterboxing never ensured that the TV displaying it was showing the full image, just that it was present in the signal, while anamorphic enhancement on DVDs was designed to maximize the resolution used by widescreen films on the format, again with no compensation for overscan. Defenders further argue that

494-556: The image is visible on these TVs; in a best case scenario the TV overscan cuts off nothing but the windowbox borders. It originally was used only for the credit sequences in 4:3 films, where the text could extend out to the very edges of the image, but it was gradually adopted to be used throughout the film. Critics often argue that windowboxing of this ratio is unnecessary due to the image loss caused by overscan being negligible. Moreover, for those who watch such films on computer monitors or newer TVs, both of which have little to no overscan,

520-427: The lost image information was not restored by the process. Furthermore, DVD video has slightly more horizontal resolution than analogue video, giving it an effective aspect ratio of 1.38:1 which allows for a nearly full-screen 1.37:1 image to be stored without cropping, although whether this extra image information can be properly displayed depends on the equipment used. Ultimately, the use of 4:3 windowboxing on video

546-423: The most important features of each shot or having to resort to pan and scan or letterboxing . A 14:9 safe area is often chosen as a compromise between 4:3 and 16:9 frame formats. This article related to film or motion picture terminology is a stub . You can help Misplaced Pages by expanding it . Windowbox (film) Windowboxing (also called either "pictureboxing" or the "postage stamp effect") in

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572-427: The plane and toward the viewer by having them extend outside the windowbox. Windowboxing has also been used in the instance of transferring films with the academy ratio of 1.37:1 to video, as evidenced in recent DVD releases of older films shot in this standard. This is to compensate for the overscan on many 4:3 TVs, which cuts off part of all four sides of the image. Windowboxing ensures that either more or all of

598-618: The provider's 'primary' station for a network), to the displeasure of broadcasters. Without AFD, either a fixed letterbox or center-cut will be required on a station-by-station basis. A fixed letterbox will result in an undesirable windowbox (i.e., a combination of letterbox and pillarbox , also called "postage stamp") effect on SD originated programming. A fixed center-cut will result in loss of important picture content on certain HD content (e.g., an HD sports broadcast containing score graphics formatted for 16:9 display). The following image illustrates

624-442: The resolution of the original image. It can occur when a 16:9 film is set to 4:3 ( letterbox ), but then shown on a 16:9 TV or other output device. It can also occur in the opposite direction (4:3 to 16:9 to 4:3). Few films have been released with this aspect ratio — one example is The Crocodile Hunter: Collision Course , which had numerous scenes with Steve & Terri Irwin using widescreen pillar boxing. On rare occasion,

650-440: The theatrical and Widescreen DVD release, the beginning of the film is windowboxed until Kenai , the main character, becomes a bear. This is to show that his world-view, and his perspective on nature, has widened. A form of windowboxing is also occasionally encountered in 3D film ; by containing the reference plane in a box smaller than the actual screen, the filmmaker can increase the stereoscopic effect of objects coming out of

676-399: The traditional method of cropping 1.37:1 aspect ratio films to fill the 4:3 (1.33:1) ratio of standard definition video causes visual information, however negligible, to be permanently lost from the film. However, critics point out that this situation can be remedied by letterboxing the 1.37:1 image instead of windowboxing, while windowboxed images are often still in a 4:3 aspect ratio, meaning

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