High Efficiency Video Coding( HEVC )

High Efficiency Video Coding (HEVC) is a video compression standard, a successor to H.264/MPEG-4 AVC (Advanced Video Coding), that was jointly developed by the ISO/IEC Moving Picture Experts Group (MPEG) and ITU-T Video Coding Experts Group (VCEG).

HEVC is said to double the data compression ratio compared to H.264/MPEG-4 AVC at the same level of video quality. It can alternatively be used to provide substantially improved video quality at the same bit rate. It can support 8K UHD and resolutions up to 8192x4320.

The first version of the standard was completed and published in early 2013. Several extensions to the technology remain under active development, including range extensions (supporting enhanced video formats), scalable coding extensions, and 3D video extensions.

EPG - Electronic Program Guide

EPG gives the information to the user about the events of a services present in DVB. The EPG data is sent through EIT (Event Information Table). The information such as, Program name, Start Date, Start Time, Duration, Short and Detailed description are possible with this EIT data.

The information comes under EIT are classified into three categories, they are,

• Current/Next Information
• Event Schedule
• Extended Info

Standards Other than DVB

1. ATSC

The Advanced Television Systems Committee (ATSC) is the group that helped to develop the new digital television standard for the United States, also adopted by Canada, Mexico, and South Korea and being considered by other countries.It is intended to replace the NTSC system and produce wide screen 16:9 images up to 1920×1080 pixels in size—more than six times the display resolution of the earlier standard.

2. ISDBIntegrated Services Digital Broadcasting (ISDB) is the digital television (DTV) and digital audio broadcasting (DAB) format that Japan has created toallow radio and television stations there to convert to digital.

3. ARIB

The Association of Radio Industries and Businesses, commonly known as ARIB, is a standardization organization in Japan.

ARIB is designated as the center of promotion of the efficient use of the radio spectrum and designated frequency change support agency.

4. SBTVD

Brazilian Digital Television System is a proposed digital television standard for Brazil.

What is teltext?

Teletext is an information retrieval service provided by television broadcast companies. Teletext pages can be viewed on television sets with suitable decoders. They offer a range of text-based information, usually including national, international and sporting news, weather and TV schedules. Subtitle (or closed caption) information is also transmitted in the teletext signal.

DiSEqC

DiSEqC (Digital Satellite Equipment Control) is a special comunication protocol for use between a satellite receiver and a device such as a multi-dish switch or a small dish antenna rotor. It is compatible with the actuators used to rotate large C band dishes if used with a DiSEqC positioner. It relies only on the coaxial cable to transmit both bidirectional data/signals and power.

Applications of DiSEqC:DiSEqC 1.0 circuit max. 4 LNB`s

DiSEqC 1.0: 4 LNB's Separate Option/Position



Diseqc A = Position A Option A
Diseqc B = Position B Option A
Diseqc C = Position A Option B
Diseqc D = Position B Option B

DiSEqC 1.0 + 0/12 Volt: 8 LNB's



DiSEqC 1.0 + Toneburst + 0/12 Volt: 12 LNB's

Attitudes in the receiver menu:
LNB1 = DiSEqC A, 0 Volt, ToneBurst Sat A
LNB2 = DiSEqC A, 0 Volt, ToneBurst Sat B
LNB3 = DiSEqC B, 0 Volt, ToneBurst aus
LNB4 = DiSEqC C, 0 Volt, ToneBurst Sat A
LNB5 = DiSEqC C, 0 Volt, ToneBurst Sat B
LNB6 = DiSEqC D, 0 Volt, ToneBurst aus
LNB7 = DiSEqC A, 12 Volt, ToneBurst Sat A
and so on to LNB12.

DiSEqC 1.0 + Toneburst + 2 Tuner: 12 LNB's


DiSEqC 1.1: 16 LNB's


DiSEqC 1.1: 64 LNB's



DiSEqC 1.2 of 1.3 Motor : 1 LNB


DiSEqC 1.2: 10 LNB's without Motor


DiSEqC 1.0 + ToneBurst + DiSEqC 1.2 + 2 Tuner: 16 LNB's


DiSEqC 1.0 + 0/12 Volt + DiSEqC 1.2 or 1.3 Motor: 5 LNB's

What is ATSC?

ATSC (Advanced Television Systems Committee) is a group which defines the standards for digital television transmission in the United States and many other counties.

ATSC is the digital replacement for the earlier analog standard, NTSC.

The ATSC standards are created by the Advanced Television Steering Committee, whose charter members are the Electronic Industries Association (EIA), the Institute of Electrical and Electronic Engineers (IEEE), the National Association of Broadcasters (NAB), the National Cable Television Association (NCTA), and the Society of Motion Picture and Television Engineers (SMPTE).

The ATSC standards include high definition television (HDTV), standard definition television (SDTV), data broadcasting, multichannel surround-sound audio, and satellite direct-to-home broadcasting.

In addition to the United States, ATSC is also used in Canada, South Korea, Argentina, and Mexico.

ATSC uses 8VSB (8-level Vestigal Side-Band) modulation and MPEG-2 compression.

What is HDTV?

HDTV (High Definition Television) is one of the DTV (Digital TV) standards. HDTV will eventually replace analog television.

HDTV offers resolutions of 720p, 1080i, and 1080p.

The 720p format offers 720 lines of horizontal resolution with progressive scan. Progressive scan means that every line is refreshed in each frame update.

The 1080i format offers 1080 lines of horizontal resolution with interlacing. Interlacing means that every other line is refreshed in each frame update. This means that it requires two frame updates to repaint the entire screen.

1080p offers the best of both worlds, 1080 lines of progressively scanned video.

HDTV features an aspect ratio of 16:9.

The HDTV standard also includes the use of 5.1 Dolby Digital surround sound (AC-3).

Each HDTV channel provides 19.39Mbps of bandwidth.

HDTV utilizes MPEG-2 compression.

HDTV is part of a larger set of standards called ATSC.

The FCC (Federal Communications Commission) has mandated that all licensed television stations be capable of broadcasting DTV by 2007.

What is aspect ratio?

Aspect Ratio is the ratio of a picture's width to its height.

NTSC television uses a 4:3 aspect ratio.

HDTV and SDTV feature a 16:9 aspect ratio.

Movie theaters typically use an aspect ration of 1.85:1 or 2.35:1.

Converting a movie to television requires either pan and scan or letterboxing.

Pan and scan is a process where technicians remove portions of the left or right side of the video to convert the aspect ratio.

Letterboxing is displaying the full picture in the center of the screen, with black bars above and below it.

What is MPEG-2?

MPEG-2 (Motion Picture Experts Group - 2) is a compression standard for digital television.

MPEG-2 compression enables digital television broadcasters to transmit video streams with higher resolution and audio streams with higher quality sound while using as little bandwidth as possible.

MPEG-2 is capable of reducing the amount of bandwidth utilized by as much as 55 to 1.

MPEG-2 is utilized by DVB, HDTV, and DVD.

MPEG-2 has been adopted as ISO Standard 13818-1.

Difference between Program Stream and Transport Stream

From ISO 13818-1

Transport Stream:

• Transport stream is a stream definition which is tailore for communicating or storing one ore more programs of coded data according to ITU-T Rec. H.262 ISO/IEC 13818-2 and ISO/IEC 13818-3 and other data in environments in which significant errors may occur. Such errors may be manifested as bit value errors or loss of packets.
• Transport Streams May be Fixed or Variable rate. In either case, the constituent elementary stream may be either fixed or variable rate.
• Transport Stream rate is defined by the values and locations of Program Clock Reference (PCR) fields, which in general are separate PCR fields for each program.
• Transport Stream may be constructed from
• a) from one or more elementary coded data streams
• b) from Program Streams
• c) from other Transport Streams which may themselves contain one or more programs.
• Transport Streams are constructed in two layers: a sytem layer and a compression layer. The input stream to the Transport Stream decoder has a system layer wrapped about a compression layer. Inpute Streams to the Video and Audio decoders have only the compression layer.
• Transport Stream system layer is divided into two syb-layers, one for multiplex-wide operations (the Transport stream Packet Layer), and one for stream-specific operations (the PES packet layer).

Program Stream:

• The Program Stream is a stream definition which is tailored for Commnucating or storing one program of coded data and other data in environments where errors are very unlikely, and where processing of system coding e.g by software, is a major consideration.
• Program Streams may be fixed or variable rate. In either case, the consituent elementary streams may be either fixed or variable rate.
• The Program Stream rate is defined by the values and locations of the System Clock Reference (SCR) and mux_rate fields.
• Program Streams are constructed in two layers: a system layer and a compression layer. The inpur to the Program Stream Decoder has a system layer wrapped about a compression layer. Input streams to the video and Audio decoders have only the compression layer.
• The Program Stream system layer is divided into two sub-layers, one for multiplex-wide operations (the pack layer), and one for stream-specific operations (the PES packet layer).

Analog Versus Digital Transmission

http://www.informit.com/articles/article.asp?p=24687&seqNum=5&rl=1

Feature Analog Characteristics Digital Characteristics

Signal Continuously Variable Discrete Signal 
Bandwidth Low bandwidth High Bandwidth 
Speed Low High 
Error Rate High 10^-5 bits Low 10^-7

CI and CAM

Common Interface ( CI )
Common Interface ( CI ) To decode encrypted programmes, you need a subscription to the appropriate broadcaster along with hardware that enables you to use the decryption card (smart card) sent to you by the broadcaster. The first piece of hardwareis the Common Interface (CI), which is connected directly to the DVB card. A Conditional Access Module (CAM) isinserted into the CI, and the CAM is used to house the smartcard itself. Unfortunately it is easy to get these namesconfused.

Again and again Conditional Access Modules are referred to as CI modules - which can be confusing, since CIs themselves can also be designed in the form of pluggable modules(for example, the Siemens DVB-C module).

CIs are available in the form of PCI cards, DVB card daughterboards or as modules that can be installed in a 3.5" drive bay.Due to these different formats, you should ensure that the module you purchase can be used with your DVB card. Not all DVBcards have the connections required for CIs, so make sure in advance that the Ci fits your card.

Some broadcasters specify in their Terms and Conditions that you have to use a specific certified receiver to receive and decrypt their programmes - so far, however, there is not certified CI / CAM.



Conditional Access Module (CAM)
A Common interface (CI) module can be used to house many different peripheral devices, such as a modem, additional memory, games consoles, or more usually a Conditional Access Module (CAM) - sometimes referred to as a Common Interface Module (CIM, CI module). The CAM provides space for one or two smartcards (depending on the CI) supplied by the broadcaster.

Encryption systemsThere are various different encryption systems, which are not mutually compatible. The CAM must be suitable for the system you wish to decrypt - often a CAM is only suitable for one system, while other CAMs can be used with a number of systems (e.g. the Joker CAM).

Below are examples of encryption systems (their use and sample broadcasters are given in brackets):

Irdeto BetaCrypt (previously used by Premiere) Premiere Nagra (currently used by Premiere) Seca (Aston Canal+) Viaccess (previously used by Viasat) Conax (Canal+ Scandinavia, SVT) CryptoWorks (ORF, Xtra Music Payradio, Wizja +, MTV, DigiTurk, CzechLink, Easy.tv) NDS (Sky, currently used by Viasat)

The best-known CAM is probably in the Alphacrypt CAM, which works with VDR. Unfortunately CAMs are not usually particularly cheap, costing between 60 and 180 euros (the Alphacrypt CAM is at the top end of this price range). Obviously you can sometimes obtain them more cheaply on the second-hand market.

Mascom now produces an Alphacrypt Light CAM, which works well with VDR (tested with vdr-1.3.16 and Fujitsu-Siemens DVB-C PCI with CI) and KabelDeutschland Digital or Premiere. The high-street price for this CAM is 66 euros.

Tuner

Tuner an electronic receiver that detects and demodulates and amplifies transmitted signals

DENC

DENC means Digital Encoder. In order to display digital video on analog TVs the video signal must be encoded in standards such as PAL, NTSC or SECAM. This operation is performed by a DENC hardware device.

What is DVB?

DVB (Digital Video Broadcast) is a set of standards for the digital transmission of video and audio streams, and also data transmission.

The DVB standards are maintained by the DVB Project, which is an industry-led consortium of over 260 broadcasters, manufacturers, network operators, software developers, regulatory bodies and others in over 35 countries.

DVB standards are available on the web at the ETSI Publications Download Area.

DVB has been implemented over satellite (DVB-S, DVB-S2), cable (DVB-C), terrestrial broadcasting (DVB-T), and handheld terminals (DVB-H).

DVB utilizes MPEG-2 compression.

DVB primarily uses Musicam audio encoding, but also has optional support for AC3.

What is Reed-Solomon?

Reed-Solomon is an algorithm for Forward Error Correction (FEC).

Reed-Solomon was introduced by Irving S. Reed and Gustave Solomon of MIT Labs in Polynomial Codes Over Certain Finite Fields, which was published in the Journal of the Society for Industrial and Applied Mathematics in 1960.

Reed-Solomon does not specify a block size or a specific number of check symbols. These variables can be set to the best variables for each transmission medium.

DVB uses Reed Solomon coding configured to use blocks of 188 information symbols and 16 check symbols, which results in a total block size of 204 symbols.

Reed-Solomon is often abbreviated as RS.

What is Forward Error Correction (FEC)?

Forward Error Correction (FEC) is a type of error correction which improves on simple error detection schemes by enabling the receiver to correct errors once they are detected. This reduces the need for retransmissions.

FEC works by adding check bits to the outgoing data stream. Adding more check bits reduces the amount of available bandwidth, but also enables the receiver to correct for more errors.

Forward Error Correction is particulary well suited for satellite transmissions, where bandwidth is reasonable but latency is significant.

Forward Error Correction vs. Backward Error Correction

Forward Error Correction protocols impose a greater bandwidth overhead than backward error correction protocols, but are able to recover from errors more quickly and with significantly fewer retransmissions.

What is 8PSK?

8PSK (8 Phase Shift Keying) is a phase modulation algorithm.

Phase modulation is a version of frequency modulation where the phase of the carrier wave is modulated to encode bits of digital information in each phase change.

The "PSK" in 8PSK refers to the use of Phased Shift Keying. Phased Shift Keying is a form of phase modulation which is accomplished by the use of a discrete number of states. 8PSK refers to PSK with 8 sates. With half that number of states, you will have QPSK. With twice the number of states as 8PSK, you will have 16PSK.

Because QPSK has 8 possible states 8PSK is able to encode three bits per symbol.

8PSK is less tolerant of link degradation than QPSK, but provides more data capacity.

What is QPSK?

QPSK (Quadrature Phase Shift Keying) is a phase modulation algorithm.

Phase modulation is a version of frequency modulation where the phase of the carrier wave is modulated to encode bits of digital information in each phase change.

The "PSK" in QPSK refers to the use of Phased Shift Keying. Phased Shift Keying is a form of phase modulation which is accomplished by the use of a discrete number of states. QPSK refers to PSK with 4 states. With half that number of states, you will have BPSK (Binary Phased Shift Keying). With twice the number of states as QPSK, you will have 8PSK.

The "Quad" in QPSK refers to four phases in which a carrier is sent in QPSK: 45, 135, 225, and 315 degrees.

QPSK Encoding

Because QPSK has 4 possible states, QPSK is able to encode two bits per symbol.

Phase                Data
45  degrees       Binary 00
135 degrees       Binary 01
225 degrees       Binary 11
315 degrees       Binary 10

QPSK is more tolerant of link degradation than 8PSK, but does not provide as much data capacity.

What is symbol rate?

The symbol rate is the rate of state changes on a communications circuit.

If a circuit can carry two tones per second, the circuit has a symbol rate of two.

Circuits then use different modulation techniques to carry multiple bits per symbol.

If the circuit is limited to two different tones, the first tone can represent a 0 and the second tone can represent a 1. In this circuit, the symbol rate is the same as the bit rate.

If the circuit can carry four different tones, then the tones can be used to encode twice as many bits per symbol. In this circuit, the bit rate is now twice the symbol rate.

Using more tones allows more bits per second (bps) to be squeezed out of every symbol, but this also requires higher quality circuits. If the circuit is not high enough quality, the number of retransmissions will cause the circuit to be slower than with a lower number of tones.

The choice of how many tones to use is determined by the modulation algorithm chosen. QPSK uses four tones, 8PSK uses eight tones.

The use of 4 tones is standard in the satellite world. In the cable television world, the higher quality transmission medium enables 64 tones to be the standard, using 64QAM modulation.

Symbol Rate is abbreviated as SR.

The symbol rate is also known as the baud rate.