MinDig TV
Service Management
Implementation Guideline
for
Digital Television Receivers
for use in
Hungarian Digital Terrestrial Television Broadcasting
Part of the MinDig TV Receiver Specification
Version 0.9.2
2009-10-21
Created by:Viktor Till
Company:Antenna Hungária
Contact:
Table of contents
1.Introduction
1.1.Scope
1.2.Document History
1.3.References
1.4.Terminology
1.5.Definitions and Abbreviations
1.5.1.General Definitions
1.5.2.Definitions of the Present Document
1.5.3.Abbreviations
2.Overview of Service Management
3.Related Service Information
3.1.DVB Networks
3.1.1.General
3.1.2.Original Network Identifiers – Hungarian Networks
3.1.3.Network Identifiers
3.1.4.Transport Stream Identifiers
3.1.5.Service Identifiers
3.2.Network Information Table
3.2.1.Terrestrial_delivery_system_descriptor
3.2.2.Frequency_list_descriptor
3.2.3.Logical_channel_descriptor
3.3.Service Description Table
3.3.1.CA_identifier_descriptor
3.3.2.Service_descriptor
3.3.2.1.Service Types and Categories
3.3.3.Linkage_descriptor
4.Creating Scan List - Service Discovery
4.1.Front-end
4.2.General Rules
4.3.Basic Scanning Procedures
4.3.1.Full-band Scan
4.3.1.1.Service Initialization Scan
4.3.1.2.Automatic Scan
4.3.1.3.Automatic “quasi-static” Update
4.3.2.Single Frequency Scan
4.4.Signal Quality Indicator
5.Logical Channel Numbering
5.1.General
5.2.Ordering Services inside the Services List
5.3.Conflict Handling of Logical Channel Ordering
5.4.Example
6.Automatic “Quasi-static” Update
6.1.General
6.2.Logical_channel_descriptor Changing
6.3.Channel List Changing
6.3.1.Adding a New Service
6.3.2.Removing an Existing Service
6.4.Network Evolution
6.4.1.Adding a New Network/Multiplex
6.4.2.Removing an Existing Network/Multiplex
6.4.3.Changing Network/Multiplex Identifiers
7.Service Presentation
7.1.Navigation
7.1.1.Service Selecting
7.1.2.Unvisable Servicesd
7.1.3.Favorite List(s)
7.1.4.Encrypted Services
7.1.5.Parental Lock
7.2.PSI Handling
7.3.Service Replacement
7.4.Regionalization
- Introduction
1.1.Scope
The present document is part of “MinDig TV Receiver Specification”.
It expands the descriptions of the “MinDig TV General Receiver Requirements” about the service handling.
To develop a MinDig TV compliant receiver, all the mandatory requirements of the present document shall be satisfied, while it is strongly recommended to follow the present recommendations. Furthermore, a MinDig TV receiver shall satisfy all the parts of the “MinDig TV Receiver Specification”.
The MinDig TV Receiver Specifications does not require the implementation of the IEC 62216, but on those fields where is not any related requirement described here, the IEC 62216 should be handled as a guideline.
1.2.Document History
Version / Date / Comments / Editor0.1.x / 14.09.2009 / First public version / V. Till
0.9.x / 19.10.2009 / Pre-release / V. Till
1.0.1 / 09.11.2009 / First official release / V. Till
1.3.References
[1] ETSI EN 300744: "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for digital terrestrial television".
[2] ISO/IEC 13818-1: “Information technology - Generic coding of moving pictures and associated audio information: Systems”.
[3] ETSI EN 300468: "Digital Video Broadcasting (DVB); Specification for Service Information (SI) in DVB systems".
[4] ETSI TR 101211: "Digital Video Broadcasting (DVB); Guidelines on implementation and usage of Service Information (SI)".
[5] ETSI TS 101162: "Digital Video Broadcasting (DVB); Allocation of Service Information (SI) codes for DVB systems".
1.4.Terminology
Shall (must, mandatory, required)These words mean that the item is mandatory.
Shall not (must not)These words mean that the item is forbidden.
Should (recommended, preferred)These words mean that the item is not mandatory, but is highly recommended.
MinDig TV receiver (receiver)The device suitable for the handling of DVB-T services according to the requirements of the MinDig TV (DTT?) General Receiver Requirements and the related guidelines. The MinDig TV receiver may be an STB, IDTV or PC-based device or a part of the above.
1.5.Definitions and Abbreviations
1.5.1.General Definitions
See the “General Definitions” section of the “MinDig TV General Receiver Requirements” specification.
1.5.2.Definitions of the Present Document
Modulation parametersAll the parameters signaled by the TPS (constellation characteristics, α value, code rate(s), super-frame indicator and guard interval). In term of present document, the centre frequency and the signal bandwidth are not transmissionparameters.
Duplicated serviceA service available on different frequencies with the same original_network_id / transport_stream_id / service_id triplet
Scan listThis is a hypothetic list that contains all the available DTT services found by performing any automatic and manual frequency scan. It should include all the available DVB parameters,reception quality, logical channel number and service type informationof each service.The scan list should not be segmented by any condition. It should be kept up-to-date by the automatic “quasi-static” update function.[tv1]
Service listThis is the list that shall be accessed by the viewer. It is based on the scan list, but it shall be segmented by service categories (e.g. TV, Radio, Others, etc.) and ordered by logical channel numberinformation, if present. It should not be editable by the viewer. If this is the case, then it shall be kept up-to-date by the automatic “quasi-static” update function. Otherwise, the automatic “quasi-static” update function shall not have any effect on this list.
Favorite list(s)It is strongly recommended to implement some form of favorite list(s) in which the viewer has full control over the service editing. He/she should be able to add (from the service list), remove and order the items of this list. The automatic “quasi-static” update functionshould not have any effect on the favorite list(s), unless a service is removed.
1.5.3.Abbreviations
DTTDigital Terrestrial Television
LCNLogical Channel Numbering
MFNMulti Frequency Network
NIDNetwork_ID
ONIDOriginal_Network_ID
ESElementary Stream
LCDLogical Channel Descriptor
LCNLogical Channel Numbering
NITNetwork Information Table
PSIProgram Specific Information
SDTService Description Table
SIService Information
TSTransport Stream
- Overview of Service Management
A MinDig TV compliant receiver shall offer at least the following service management related features to the viewer:
service initialization full-band scan,
manual full-band scan (automatic scan),
singlefrequency scan (manual scan),
signal quality indicator,
service categorization,
LCN (Logical Channel Numbering) handling,
automatic quasi-static scan/service lists update,
manual editing of service ordering (favorite lists),
appropriate presentation of services.
By the full-band scan procedures, the receiver shall be able to discover all the available multiplexes and servicesbroadcast by the HungarianDTT (Digital Terrestrial Television) networks. The receiver shall offer an appropriate function as well to indicate signal quality information about anyDVB signal selected by the viewer.
The receiver shall be able to categorize the received services by their service_type, and it shall be capable of interpreting the transmitted logical channel numbering information. Based on these features, the receiver shall be able to build-up the service list, and it shall save this list into the non-volatile memory. By default, the service list shall be always ordered accordingto the transmitted logical channel numbering.
It is recommended to forbid the viewer tochange the default service list. If this is the case, then after any manual scan and automatic updatethe receiver shall always organize the service list according to the transmitted logical channel numbering information.
The receiver shall monitor the service list related quasi-static SI tables (NIT and SDT), and in case of changing the relevant service lists shall be updated. These updates should disturbance the viewer as less as possible.
- Related Service Information
3.1.DVB Networks
3.1.1.General
Regarding the handling of DVB networks, the MinDig TV compliant receiver shall be capable of interpreting the content of NIT and SDT in accordance with EN 300468 [3] and TR 101211 [4].
In addition to the referred ETSI documents, due to the regulation of the Hungarian National Telecommunication Authority, the receiver shall match to special requirementsdescribed below.
3.1.2.Original Network Identifiers – Hungarian Networks
In addition to the original_network_id value (0x22C7) registered by the DVB office, the MinDig TV compliant receiver shall identify and handle a range of values from 0x3401 to 0x340C [VT2]together with the value of 0x22C7 as Hungarian DTT networks. Thus, the multiplexes of the Hungarian DTT broadcasting may have different ONIDs.
3.1.3.Network Identifiers
A NIT actual section (table_id = 0x40), contained in a multiplexthatbelongs to the Hungarian DTT networks, may refer to other Hungarian multiplexes in its second loop, even if, these referred multiplexes are transmitted withdifferentNIDs.
3.1.4.Transport Stream Identifiers
A multiplex is uniquely identified by its original_network_id and transport_stream_id.
Multiplexes within the Hungarian DTT networks may have unique transport_stream_id independent from the network operator.
3.1.5.Service Identifiers
A service is uniquely identified by its original_network_id / transport_stream_id / service_id triplet.
3.2.Network Information Table
Descriptor / Tag / Actual / Other / Loopnetwork_name_descriptor / 0x40 / M m / O m / first
linkage_descriptor / 0x4A / M m / O m
private_data_specifier_descriptor / 0x5F / C / C
terrestrial_delivery_system_descriptor / 0x5A / M m / O m / second
frequency_list_descriptor / 0x62 / M m / O m
service_list_descriptor / 0x41 / R / R
private_data_specifier_descriptor / 0x5F / C / C
logical_channel_descriptor / 0x83 / O m / O
Table 1 – NIT descriptors
3.2.1.Terrestrial_delivery_system_descriptor
The terrestrial_delivery_system_descriptor is always used in the NIT. This information is static.The modulationparameterslisted within the descriptor should be handled by the receiver as a recommendation when trying to tune to a multiplex that may not tuned before. Otherwise, the receiver should use the automatically detectedmodulationparameters from the TPS.
Due to the MFN conditions, the same multiplex can be broadcast in different regions by using different modulation parameters including the centre frequency value. Thus, the value of the centre_frequency field in the terrestrial_delivery_system_descriptor can be invalid at some reception points. Therefore, this field shall be also handled as only a recommendation. If alternative frequencies are used then the other_frequency_flag shall indicate this.
3.2.2.Frequency_list_descriptor
The frequency_list_descriptor may be used in the NIT.This information is quasi-static It is valid, if the other_frequency_flag in the terrestrial_delivery_system_descriptor is set. The frequency list descriptor gives the complete list of additional frequencies for a certain multiplex which is transmitted on multiple frequencies.
If any DVB service (e.g. System Software Update or service replacement) refers to a given multiplex by its unique identifier (original_network_id / transport_stream_id) via the NIT, then the receiver shall be able to find this multiplex by searching on every possible centre frequency listed in the terrestrial_delivery_system_descriptor and in the frequency_list_descriptor.
3.2.3.Logical_channel_descriptor
The logical_channel_descriptor provides a default channel number label for services. Thisinformation is quasi-static. The logical channel descriptor may be inserted once in the seconddescriptor loop of the NIT.
Syntax / No. of bits / Typelogical_channel_descriptor(){
descriptor_tag
descriptor_length
for (i=0; i<N;i++){
service_id
visible_service_flag
reserved
logical_channel_number
}
} / 8
8
16
1
1
14 / uimsbf
uimsbf
uimsbf
bslbf
bslbf
uimsbf
Table 2 – Logical_channel_descriptor
descriptor_tag:This shall be assigned to be 0x83.
service_id:This is a 16-bit field which serves as a label to identify this service from any other service within the network. The service_id is the same as the program_number in the corresponding program_map_section. Services shall be included irrespective of their running status.
visible_service_flag:This 1-bit field when set to ‘1’/’true’ indicates that the service is normally visible and selectable(subject to the service type being suitable, etc.) via the receiver service list. When set to ‘0’/’false’ this indicates that thereceiver is not expected to offer the service to the user in normalnavigation modes. However, the receivershould provide a mechanism to access theseservices (for example, by direct entry of the logical channel number).
logical_channel_number:This is a 14-bit field which indicates the broadcaster preference for ordering services.
3.3.Service Description Table
Descriptor / Tag / Actual / OtherCA_identifier_descriptor / 0x53 / M m / O m
service_descriptor / 0x48 / C m / C m
linkage_descriptor / 0x4A / C / C
Table 3 – SDT descriptors
3.3.1.CA_identifier_descriptor
This descriptor may be present if the service or at least one service component is associated with a conditional access system and identifies the CA system type by means of the CA_system_id. In presence of this descriptor, the receiver shall always try to present the service to the viewer. In case the service is effectively scrambled, and the relevant CA system is not present, the receiver shall display a notification message. (for further details, see the “CA Requirements” section of“MinDig TV General Receiver Requirements” specification)
3.3.2.Service_descriptor
The service_descriptor provides the names of the service provider and the service in text form together with the service_type.This information is quasi-static.
The receiver shallsupport the displaying of the service name in accordance with the Latin-2 character set, the latter including all special Hungarian characters. The receiver should be capable of interpreting the control bytes marking the character sets, defined in Annex A of EN 300 468; it is, however, sufficient to support the display of the Latin-2 character set. It is mandatorythat the default character set of the service name presentation is Latin-2 if the Hungarian language is selected for displaying.
3.3.2.1.Service Types and Categories
The receiver shall only list a service in their service selection interfaces where the service is of a type that the receiver is able to present to the viewer. Service types that are not supported by the receiver shall be ignored.
The receiver shall be able to recognize and handle at least the mandatory items of the following table:
service_type / Service Description / Type / Status / Category / Priority0x01 / Digital television / MPEG-2 SD / M / TV / 4
0x02 / Digital radio sound / MPEG-1 Layer II / M / Radio / 2
0x03 / Teletext / R / Others / 1
0x0A / Advanced codec digital radio sound / MPEG-4 AAC,AC-3 / M / Radio / 1
0x0C / Data broadcast / e.g. SSU / M / Others / 2
0x11 / MPEG-2 HD digital television / MPEG-2 HD / R / TV / 3
0x16 / Advanced codec SD digital television / MPEG-4 AVC / M / TV / 2
0x17 / Advanced codec SD NVOD time-shifted / MPEG-4 AVC / O / TV / 6
0x18 / Advanced codec SD NVOD reference / MPEG-4 AVC / O / TV / 6
0x19 / Advanced codec HD digital television / MPEG-4 AVC / M / TV / 1
0x1A / Advanced codec HD NVOD time-shifted / MPEG-4 AVC / O / TV / 5
0x1B / Advanced codec HD NVOD reference / MPEG-4 AVC / O / TV / 5
Others / Others / - / O / Others
M: mandatory, R: recommended, O: optional item to support
‘1’ is the highest priority
Table 4 – Service types and categories
3.3.3.Linkage_descriptor
Linkage_type: 0x05. For further details, see Section 7.3.
- Creating Scan List - Service Discovery
4.1.Front-end
The MinDig TV compliant receiver shall include at least one tuner/demodulator for reception of signals fromterrestrial, broadcasting in accordance with EN 300744 [1].
Regarding the supported frequencies and bandwidthsas well as the transmission parameter requirements, see the “Front-end Requirements” section of the “MinDig TV General Receiver Requirements” specification
The receiver shall be able to tune all the available multiplexes broadcast on the supported frequencies and bandwidths. The tuning process shall be fully automated; the receiver shall be able to detect the transmission parameters from the transmission itself, by the TPS bits, in order to reduce the tuning time.
The receiver shall detect achange of transmission parameters signaled in the TPS as well, in order to reduce therecovery time and output an error free bitstream as soon as possible.This shall take less than one second for any change. The transmissionparameters should be continually saved and use in case of service switching.
4.2.General Rules
Due to the MFN conditions, multiple reception of the same multiplex on different frequencies is possible. Thus, multiple reception of the same service(same triplet of original_network_id, transport_stream_id andservice_id) is possible as well.However, the receiver shall only display a service once in the service list. In case of duplicated service the receiver shall select the best-quality instance, unless the viewer overrides this decision.
If the real reception centre frequency of a given multiplex is present in the terrestrial_delivery_system_descriptor or in the frequency_list_descriptor, then the multiplex shall be handled as a correct bitstream.
During the scanning procedures, if the receiver findsany unexpected or unknowndescriptor in the NIT or SDT (or in PSI tables), then it shall be ignored, while the process shall be continued without missing any potential service. In case of corrupt descriptor, including corrupt descriptor_length, the receiver shall be as robust as possible, and it should not miss any potential service.
The receiver shall not apply any filtering based on the values of original_network_id and network_id. In other words, the receiver shall not apply any country / operator based filtering; all the tuned services shall be saved into the service list.
4.3.Basic Scanning Procedures
The scanning procedures shall adjust the scan and service lists, but it should not have any effect on the favorite list(s). The first step of a scanning procedure shall be the frequency scanning. During this step, the found services shall be added to the scan list. After the scan list is up-to-date, as part of the scanning procedure, the receiver shall regenerate the service list. Regarding the service ordering within the service list, see Chapter 5.
The scan list is a hypothetic list that can not be accessed by the viewer. The procedures described below may not be implemented by the receiver in the same way, but the results regarding the service list functions shall be the same.
If a previously found multiplex, identified by its original_network_id and transport_stream_id, is found againby afrequency scanning procedure, even if it is found at another frequencywhere it was tuned before, then the scan list shall be updated in accordance with the followings:
-if new service is found in the multiplex then it shall be added to the scan list,
-ifduplicated service is found in the multiplex then the receiver shall decide in accordance with the scanning mode described below,
-if a previously stored service is removed from the multiplex, then it shall be removed from the scan list as well.
In addition to the mandatory scanning procedures described below, the receiver may offer further scanning solutions, e.g. manually initiated “quasi-static” update. It is accepted only if these solutions do not have any effect on the working of the mandatory procedures.
4.3.1.Full-band Scan
The full-band scan is the procedure by which the receiver re-initializes its service list. At first, the receiver shall delete the scan and service lists, after that, it shall scan the whole supported frequency range to find all the available multiplexes and services.
In case of duplicated servicefound during the full-band scan, the receiver shall automatically select the best-quality instance, unless there is a function that enables the viewer to select the service instance which shall be display in the service list. In the latter case, the receiver shall not override this selection by any “quasi-static” update. For further details, see Chapter 6.[T3]
It is recommended that the complete scan procedure takes less than 180seconds in that case when the aerial connector is unplugged.
4.3.1.1.Service Initialization Scan
During the first installation and after every factory reset, the receiver shall offer the possibility of a full-band scan, or it shall be automatically performed.
4.3.1.2.Automatic Scan
The receiver shall allow the viewer to manually initiate a full-band scanfrom the system menu.
4.3.1.3.Automatic “quasi-static” Update