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18-504: DVB-S2 is designed for broadcast services including standard and HDTV , interactive services including Internet access, and (professional) data content distribution. The development of DVB-S2 coincided with the introduction of HDTV and H.264 (MPEG-4 AVC) video codecs . Two new key features that were added compared to the DVB-S standard are: Other features include enhanced modulation schemes up to 32APSK , additional code rates , and

36-418: A Luxembourg-based company, administers the licenses for patents applying to this standard, as well as other patent pools . Standard-definition television Standard-definition television ( SDTV ; also standard definition or SD ) is a television system that uses a resolution that is not considered to be either high or enhanced definition . Standard refers to offering a similar resolution to

54-435: A wider range of applications combining DVB-S features (for household tasks), and DVB-DSNG (for professional tasks). DVB-S2 can adapt codification to maximize satellites resources value. It is compatible with last generation. The main disadvantage, there are many millions of devices deployed using DVB-S over the world which has to be upgraded. The next table compares both standards. The conversion process from DVB-S to DVB-S2

72-480: Is around 30% at the same satellite transponder bandwidth and emitted signal power. When the contribution of improvements in video compression is added, an ( MPEG-4 AVC ) HDTV service can now be delivered in the same bandwidth that supported an early DVB-S based MPEG-2 SDTV service only a decade before. In March 2014, DVB-S2X specification has been published by DVB Project as an optional extension adding further improvements. Depending on code rate and modulation,

90-514: Is being accelerated, due to the rapid increase of HDTV and introduction of 3D-HDTV. The main factor slowing down this process is the need to replace or upgrade set-top boxes, or acquire TVs with DVB-S2 integrated tuners, which makes the transition slower for established operators. Current direct-to-home broadcasters using DVB-S2 are: These broadcasters have used DVB-S2 in their internal broadcast distribution networks, but may not have instituted DVB-S2 transmissions for consumers. Sisvel,

108-785: Is inter-frame prediction which exploits temporal redundancy. Temporally independently coded so-called intra frames use only intra coding. The temporally coded predicted frames (e.g. MPEG's P- and B-frames) may use intra- as well as inter-frame prediction. Usually only few of the spatially closest known samples are used for the extrapolation. Formats that operate sample by sample like Portable Network Graphics (PNG) can usually use one of four adjacent pixels (above, above left, above right, left) or some function of them like e.g. their average. Block-based (frequency transform) formats prefill whole blocks with prediction values extrapolated from usually one or two straight lines of pixels that run along their top and left borders. Inter frame has been specified by

126-639: Is poor, where the error correction cannot compensate one will encounter various other artifacts such as image freezing, stuttering, or dropouts from missing intra-frames or blockiness from missing macroblocks . The audio encoding is the last to suffer a loss due to the lower bandwidth requirements. Standards that support digital SDTV broadcast include DVB , ATSC , and ISDB . The last two were originally developed for HDTV , but are also used for their ability to deliver multiple SD video and audio streams via multiplexing . The two SDTV signal types are 576i (with 576 interlaced lines of resolution, derived from

144-555: The CCITT in 1988–1990 by H.261 for the first time. H.261 was meant for teleconferencing and ISDN telephoning. Data is usually read from a video camera or a video card in the YCbCr data format (often informally called YUV for brevity). The coding process varies greatly depending on which type of encoder is used (e.g., JPEG or H.264 ), but the most common steps usually include: partitioning into macroblocks , transformation (e.g., using

162-455: The analog broadcast systems used when it was introduced. SDTV originated from the need for a standard to digitize analog TV (defined in BT.601 ) and is now used for digital TV broadcasts and home appliances such as game consoles and DVD disc players. Digital SDTV broadcast eliminates the ghosting and noisy images associated with analog systems. However, if the reception has interference or

180-566: The European-developed PAL and SECAM systems), and 480i (with 480 interlaced lines of resolution, based on the American NTSC system). SDTV refresh rates are 25, 29.97 and 30 frames per second , again based on the analog systems mentioned. In North America, digital SDTV is broadcast in the same 4:3 fullscreen aspect ratio as NTSC signals, with widescreen content often being center cut . In other parts of

198-517: The actual image and 16 pixels are reserved for horizontal blanking, though a number of broadcasters fill the whole 720 frames. The display ratio for broadcast widescreen is commonly 16:9 (pixel aspect ratio of 40:33 for anamorphic ); the display ratio for a traditional or letterboxed broadcast is 4:3 (pixel aspect ratio of 10:11). An SDTV image outside the constraints of the SMPTE standards requires no non-proportional scaling with 640 pixels (defined by

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216-580: The adopted IBM VGA standard) for every line of the image. The display and pixel aspect ratio is generally not required with the line height defining the aspect. For widescreen 16:9, 360 lines define a widescreen image and for traditional 4:3, 480 lines define an image. Intra-frame coding Intra-frame coding is a data compression technique used within a video frame, enabling smaller file sizes and lower bitrates, with little or no loss in quality. Since neighboring pixels within an image are often very similar, rather than storing each pixel independently,

234-433: The frame image is divided into blocks and the typically minor difference between each pixel can be encoded using fewer bits. Intra-frame prediction exploits spatial redundancy, i.e. correlation among pixels within one frame, by calculating prediction values through extrapolation from already coded pixels for effective delta coding . It is one of the two classes of predictive coding methods in video coding . Its counterpart

252-408: The image. Nominal analog blanking should not be confused with overscan , as overscan areas are part of the actual 4:3 or 16:9 image. For SMPTE 259M-C compliance, an SDTV broadcast image is scaled to 720 pixels wide for every 480 NTSC (or 576 PAL) lines of the image with the amount of non-proportional line scaling dependent on either the display or pixel aspect ratio . Only 704 center pixels contain

270-421: The introduction of a generic transport mechanism for IP packet data including MPEG-4 audio–video streams, while supporting backward compatibility with existing MPEG-2 TS based transmission. DVB-S2 achieves significantly better performance than its predecessors – mainly allowing for an increase of available bitrate over the same satellite transponder bandwidth. The measured DVB-S2 performance gain over DVB-S

288-456: The system can operate at a C/N between −2.4  dB (QPSK, 1/4) and 16 dB (32APSK, 9/10) with a quasi-error free goal of a 10 TS packet error rate. Distance to the Shannon limit ranges from 0.7 dB to 1.2 dB. Modes and features of DVB-S2 in comparison to DVB-S: Envisaged scenarios for DVB-S2 by the standard document are: DVB-S2 is 30% more efficient than DVB-S . It allows

306-528: The video into a pillarbox . The pixel aspect ratio is the same for 720- and 704-pixel resolutions because the visible image (be it 4:3 or 16:9) is contained in the center 704 horizontal pixels of the digital frame. In the case of a digital video line having 720 horizontal pixels (including horizontal blanking), only the center 704 pixels contain the actual 4:3 or 16:9 image, and the 8-pixel-wide stripes on either side are called nominal analog blanking or horizontal blanking and should be discarded when displaying

324-468: The world that used the PAL or SECAM color systems, digital standard-definition television is now usually shown with a 16:9 aspect ratio , with the transition occurring between the mid-1990s and late-2000s depending on the region. Older programs with a 4:3 aspect ratio are broadcast with a flag that switches the display to 4:3. Some broadcasters prefer to reduce the horizontal resolution by anamorphically scaling

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