WO2014127844A1

WO2014127844A1 - Method for selecting television programs and their related services and for displaying them, and related apparatus

Info

Publication number: WO2014127844A1
Application number: PCT/EP2013/053719
Authority: WO
Inventors: Ruiz Rodriguez Ezequiel
Original assignee: Saronikos Trading And Services, Unipessoal Lda
Priority date: 2013-02-25
Filing date: 2013-02-25
Publication date: 2014-08-28
Also published as: CN105009594B; CN105009594A; EP2959690A1

Abstract

A method is described for selecting television programs and their related services and for displaying them on or through a television receiver apparatus (1), said method comprising the steps of selecting, through a control device (10), a certain available television program and its related television service associated to a certain service identifier; verifying, through a central processor (5) and a tuning and demodulating unit (2), if said a certain television program selected by an user and its related television service, is broadcast with a different service identifier, with respect to the television service selected as a consequence of the program chosen by the user; controlling, through said central processor (5) and a video circuit (4) which television service, among those found services that transmit said certain television program selected by the user, has the best video quality available; displaying on a screen (7) said certain television program selected by the user, and its related television service, having said best video quality.

Description

METHOD FOR SELECTING TELEVISION PROGRAMS AND THEIR RELATED SERVICES AND FOR DISPLAYING THEM, AND RELATED APPARATUS.

DESCRIPTION

The present invention relates to a method for selecting television programs and their related services and for displaying them on or through a television receiver, as well as to the related apparatus.

In the following description, it will be apparent that a television receiver apparatus is meant to be a television set with a screen, or a satellite or cable or terrestrial set-top box capable of receiving and displaying television programs, in the latter cases by using an external screen of a monitor or a television set. Likewise, a television broadcast is meant to be any broadcasting of television signals via air or cable, for instance in accordance with one of the following standards: DVB-T ("Digital Video Broadcasting-Terrestrial"), DVB-T2, DVB-C ("Digital Video Broadcasting-Cable"), DVB-C2, DVB-S ("Digital Video Broadcasting-Satellite") and DVB-S2.

Instead a television service means a determined television transmission identified by a commercial name (like Das Erste or Das Zweite in Germany) operated by a television network (like ARD or ZDF in Germany) and composed by programs that are transmitted during the day. The same television service and consequently the same television programs can be found in different locations of the television frequency band.

More precisely in the following of the present description, with the term "service identifier" it is intended a set of data that are able to determine a specific television service (like Das Erste or Das Zweite in Germany) on the basis of information contained in the television signal and/or on the physical characteristics of the television signal. More in detail this type of information can comprise the LCN data (Logical Channel Numbering), the Service ID derived from the Service Information (SI) tables and a pair of data about the carrier frequency and Program IDentifier (PID), the latter also derived from the said Service Information tables.

In addition, when a set top box is connected to a display, this one can be either a television receiver or a simple monitor. In the last case monitors are equivalent to television receivers, because they display together with set top boxes television signals received by air or cable.

It is known that television receivers can decode television programs, transmitted in accordance with one or more of the above referred standards, that can be encoded with different systems like MPEG2 ("Moving Picture Experts Group") (for Standard Definition - SD), MPEG 4-AVC ("Advanced Video Coding") (for High Definition - HD) or HEVC ("High Efficiency Video Coding") (for Ultra High definition Television - UHDTV).

It is clear that this continuous improvement of the capabilities of encoding video signals with always increasing capacity of compressing data, creates steps of acceptance on the market, because it is not foreseeable to change all the television receivers present on the market every two or three years.

On the other hand the television networks have to face with the market situation of television receivers, where there are present old television receivers, that don't have capabilities of decoding television signals broadcast with new standards, and new television receivers that instead have capabilities of decoding new standardized television signals. For this reasons when television networks start to transmit program according with new TV standards, they broadcast simultaneously programs encoded with previous standards for allowing the television receivers equipped only with old capabilities to receive and display those programs.

It is also known that standardization bodies have also standardized the so called Logical Channel Numbers (LCN). The role of the LCN is to enable user presentation of TV services numbers in a convenient and familiar form. In fact through the use of the LCN numbers, television receivers associate the tuning information of every TV services to the keys of the control device that operates the television receiver, in order to allow the user to retrieve the preferred service just with the pressure of the keys of the control device.

When television networks start to transmit programs with the new standardized features, normally they live unchanged the LCN numbers relating to the old standard transmissions and use new LCN numbers for the programs broadcast with new standards. In this way it is difficult for an user, who is not particular skilled in the management of television receivers, to retrieve during the use of the receiver the programs broadcast with the most recent standardized technology and consequently to enjoy a better quality of vision, for instance in HD or in UHDTV.

In addition not always on the LCN numbers related to the new standardized services there is a program coded in this way (for lack of contents at the beginning of a new standard use).

This increase the possibility for the user to miss some preferred programs transmitted with newer and better quality in accordance to the new standards.

It is therefore one object of the present invention to provide a method and an apparatus for selecting television programs and their related services and for displaying them on or through a television receiver, in a "user-friendly" manner, also in presence of a mix of services/programs transmitted with different standards.

It is another object of the present invention to provide a method and an apparatus for selecting television programs and their related services and for displaying them on or through a television receiver, that allow the user to enjoy the better quality of the program when they are transmitted with enhanced television standards.

These and other objects of the invention are achieved through a method and an apparatus for selecting television programs and their related services and for displaying them on or through a television receiver as claimed in the appended claims, which are an integral part of the present description.

In short, a method and an apparatus are described for searching a television service, i.e. television programs transmitted by a television network on another service identifier, in order to view, automatically or manually, the same television service, i.e. the same television program selected by the user, but with the best video quality available on the reception side.

Further features of the invention are set out in the appended claims, which are intended to be an integral part of the present description.

The above objects will become more apparent from the following detailed description of a method and an apparatus for selecting television programs and their related services and for displaying them on or through a television receiver, according to the present invention, with particular reference to the annexed drawings, wherein:

- Figure 1 shows a scenario divided into blocks related to a television receiver apparatus according to the present invention;

- Figure 2 shows one example of data stored in a memory of the television receiver apparatus according to the present invention;

- Figure 3 shows one example of an EPG ("Electronic Program Guide") used in the present invention;

- Figure 4 shows further example of data stored in a memory of the television receiver apparatus according to the present invention;

- Figure 5 shows steps of the method according to the present invention;

- Figure 6 shows one example of data stored in a memory of the television receiver apparatus according to a variation of the present invention.

The method and apparatus according to the present invention allow a user to watch a content of a television service with the best video quality available, i.e. with a video coding system having higher performance. It is important to specify that a content of a television service is a content of a television program contained into said television service. A television service can transmit a plurality of programs.

For example, many networks broadcast the same television service in SD ("Standard Definition") with an LCN number ("Logical Channel Number") and in HD ("High definition") with another LCN number. In this case, the method and the apparatus according to the present invention provide to select or switch automatically the television service in SD, and its related current program a user wants to see, to that one having the media stream in HD, namely the one with the best video quality between SD and HD.

In general, there may also be other video standards, for example the HECV ("High Efficiency Video Coding") coding system, which allows to obtain a better video quality than conventional HD which uses an encoding H.264/MPEG-4 AVC. In fact, the standard HEVC exploits a coding algorithm called H.265 and is used for the UHD ("Ultra High Definition"). If the same television service was also available in the UHD transmission, then an apparatus 1 would have chosen the latter, having a better video quality compared between SD and HD.

It is clear that to implement the apparatus 1 and the method according to the present invention may exist different embodiments.

With reference to Fig. 1, a first embodiment of the present invention provides to associate with the same television service the various LCN numbers on which one can find the desired service. A user through the menu of the television receiver apparatus 1 associates, manually or automatically, the LCN numbers of the same television service, i.e. providing the same program. The automatic association is possible because inside the transport stream of every television service there are metadata, in particular the PSI ("Program Specific Information") tables, bringing the information about the name of the television service and the elementary streams of the program. Therefore, the television receiver apparatus 1 can automatically make a table including various LCNs that transmit the same television service, just scanning the television band and identifying the same television services, but bringing a different LCN.

In other words, this embodiments provides an association between a LCN, or, for example in the case of satellite broadcasting, a carrier frequency and a PID ("Packet IDentifier") code, with a television service name.

In the case the user performs manually the association between services and LCNs, he/she has to scroll on the menu all the services available and to mark manually those services transmitting the same program, but having a different LCN. In this way the user creates a table equivalent to that one obtained automatically as mentioned before. An example of this table is shown in the following with reference to the Fig. 2.

The television receiver apparatus 1, in particular a television set, but it may also be a set-top box, comprises a tuning and demodulating unit 2 that receives a television signal through an input 3, which may be a terrestrial or satellite antenna (but may also be the coaxial input connector of a cable television service). The tuning and demodulating unit 2 is connected to a video circuit 4 that decodes a television video signal, e.g. with MPEG2 or MPEG4 coding system, which, under the control of a central processor 5, in particular containing one or more microprocessors, supplies the television video signal to a screen 7 for reproduction; the latter being external to the television signal receiver apparatus 1 if the apparatus 1 is a set-top box.

Moreover, the apparatus 1 comprises a memory 8, in particular containing a nonvolatile read/write memory device, and a control receiver 9, also connected to the tuning and demodulating unit 2, which receives the control signals from a remote control device 10 operated by a user and supplies them to the central processor 5 (via a connection not shown in the drawing for simplicity) for the execution of functions of the apparatus 1 , including program tuning.

More in detail, when a user acts on the menu of the apparatus 1 via the remote control device 10 (control device 10 that can be implemented also on the television receiver apparatus 1), the memory 8, under the control of the central processor 5, stores the association of the various LCNs of all the available services with a unique identification code (having a relationship with the number of the keyboard of the remote control device 10), for example listing them with the LCN that has the lowest value among those of the same television service.

With reference to Figure 2, there is shown a logical table 11, which is created in the memory 8 in which for each television service and ID Code 13 (keyboard number) may exist different LCNs corresponding to the same contents, i.e. television program, but with a different video quality/standardization system, for example SD, HD or UHD. Said ID Code 13 is unique for each television service, hence for each current television program.

Once the user, manually or automatically, makes the association of the ID Code 13 and the various LCNs having different video quality/standardization system for the television services of interest, the apparatus 1 is ready for displaying television services, and its relating current television program, with the best video quality available, which is a mode that from now on we will call "best mode view".

A user can also disable such "best mode view" through the menu of the apparatus 1 ; in this case the apparatus 1 operates as a normal television receiver known in the art. When a user has previously set the "best mode view" on the apparatus 1 via the remote control device 10, and selects a television service with a low video quality, such as video quality SD, central processor 5 reads from memory 8 the data stored, for example those relating to the logical table 11 and acts consequently.

For instance, if the user selects a television service A with LCN equal to 1, then the central processor 5 reads the memory 8 and derives the other LCNs present for the same service television A. The central processor 5 identifies which LCN corresponds to the best video quality and tunes into this one. In this example, the central processor 5 identifies the LCN with number 701 which corresponds to UHD video quality. Consequently, the central processor 5 controls the tuning and demodulating unit 2 and commands to tune into the LCN with number 701. In other words, the apparatus 1 operates an automatic commutation of LCN of the television service A to the LCN one that offers the same content, but with better quality. It is clear that the central processor 5, before tuning in a permanent manner the service A associated with the LCN 701, controls that on the LCN 701 there is a broadcast service coded with UHD video quality. In the positive case the tuning of this service A associated with the LCN 701 becomes permanent until the user decides to change service/program. In the negative case the central processor 5 tunes into the LCN 301. Again it controls that on the LCN 301 there is a broadcast service coded with HD video quality. In the positive case the tuning on this service A associated with the LCN 301 becomes permanent until the user decides to change service/program. In the negative case the central processor 5 tunes into the LCN 1 associated with a service broadcast with SD.

Then, if available, the user will see on the screen 7 of the apparatus 1 the UHD contents of the television service A, i.e. those with the best video quality available for that television service A.

Similarly, if we consider the case in which the user selects the television service B, then the apparatus 1 would be automatically tuned into the LCN with number 302, i.e. one with HD video quality, because there is no others LCNs corresponding to better video quality for the television service B. Of course, also in this case the central processor 5 controls in advance that on the LCN 302 there is actually a service broadcast with HD definition.

For doing the control of which type of quality and coding is used on a certain LCN, the central processor 5 checks which decoding algorithm (MPEG2, MPEG4/ H.264, H.265) must be used for obtaining a video image from the transport stream received by the video circuit 4.

The same operations of automatic switching to the LCN having the best available quality of video content described above are also performed when a user runs the "zapping" on the apparatus 1. If there was a single LCN for a television service, the apparatus 1 does not carry out any operation.

With reference to Figs. 3 and 4, a second embodiment of the present invention provides for exploiting the data of an EPG 15 ("Electronic Program Guide") to implement the "best view mode".

When a user selects a television service, he/she watches on the screen 7 of the apparatus 1 a current television program that is broadcast at that time. If the television program/service chosen by the user is associate to an LCN where is broadcast, the program/service with a low video quality, for example SD, the apparatus 1 reads the data from the EPG 15 stored in the memory 8, namely controls if the same current television program broadcast is available on another television service, or the same but having a different LCN or different carrier frequency and PID ("Packet Identifier"), which is transmitted with a better video quality/standard than the current one.

This control is performed by comparing within the EPG 15 text strings of the names of television programs, that is, if there is the same text string of a television program name corresponding to television services with a different LCN or carrier frequency and PID; then the apparatus 1 identifies and tunes into the television service with the best video quality/standard available. For doing this, the apparatus 1 therefore tunes into the various LCN found or carrier frequency and PID, i.e. the various television services, and derives the video coding system of their television signals, in order to estimate which television service has the best video quality/standard.

For instance, if the apparatus 1 has found, through the EPG 15, two LCN that transmit the same television program substantially at the same time, and one has HD video quality and the other one has UHD video quality, then the apparatus 1 will tune into the LCN having UHD video quality.

This functional example no longer provides to create a table of LCNs associated to the various television services with various video qualities/standards, but provides a totally automatic functioning, where, this time, the apparatus 1 estimates the video quality/standard of a television service that broadcasts the same television program substantially at the same time. In this case the apparatus 1 is able to check also between different television services, but transmitting the same program, which one has the best video quality.

More in detail, if the user selects the program E on a television service A, by means of the remote control device 10, he/she wants to watch on the screen 7 of the apparatus 1 the television program E that is broadcast at that moment.

But for instance, if the television service A has a SD video quality, the central processor 5 reads data of the EPG 15 previously stored in the memory 8, namely controls whether the same television program E, currently being broadcast, is available on another television network, or the same, but nevertheless having a different LCN or carrier frequency and PID and which is transmitted with a better video quality than the current value. If this program is transmitted with better quality on a different LCN or carrier frequency and PID, then the central processor 5 provides for tuning the LCN offering the same program, but with better quality/standard.

Such control over the EPG 15 is performed by the central processor 5 which reads text strings of the names of television programs by comparing the name of the television program E with the others in the memory 8. In other words, if there is the same text string of the name of the television program E, but corresponding to the television services with a different LCN or carrier frequency and PID, then the apparatus 1 detects, i.e. reads, the television service D having the best video quality available and tunes into this last one.

For doing this, the central processor 5 controls the tuning and demodulating unit 2 to tune into the LCN with number 54, i.e. the television service D offering the same program E, but with better quality, obtaining, by the type of decoding algorithm to be used by the video circuit 4, the video coding system of the television signal, in order to estimate its video quality.

For example, if the video decoding system to be used by the video circuit 4 is MPEG2, then the central processor 5 understands that the video quality is SD. If the video decoding system to be used by the video circuit 4 is H.264/MPEG4-AVC, then the central processor 5 understands that the video quality is HD. If the video decoding system to be used by the video circuit 4 is H.265, then the central processor 5 understands that the video quality is UHD.

It is obvious that the greater are the television services found transmitting the same program, the greater is the waiting time for displaying the television program; precisely because the tuning and demodulating unit 2 must tune each television service and the video circuit 4 must send an information about the used coding system 19 to the central processor 5 which will in turn store it in the memory 8, for example as shown in table 17 of Fig. 4, all this requires a little time.

For doing this in a convenient manner, this association between the programs (taken from the EPG 15) and the LCNs or carrier frequency and PID (transmitting the same program) can be done in background when the television receiver is on stand-by situation. Therefore the entire band is scanned and every time the video circuit 4 sends the information about the used coding system 19 (obtained from the system type used for being able to decode successfully a certain service) to central processor 5, the latter stores it in the memory 8 and, when the scanning of the television services is finished, the central processor 5 has a complete list of all the available services and their video quality (deducted from the decoding system to be used for correctly receiving these services).

When the apparatus 1 receives the instruction, through the remote control device 10, to select a program, the central processor 5 reads from the memory 8 the field where is stored the information about the used coding system 19 for each television service providing said program. In the case of the television service A, the central processor 5 reads MPEG2 as coding system, and instead H.264/MPEG4-AVC for the television service D.

At this point the central processor 5 is able to determine that the television service D is that one having the best video quality available and commands the tuning and demodulating unit 2 of tune into the LCN with number 54 relative to the television service D.

Hence, the user will watch on the screen 7 of the apparatus 1 the same television program E he/she wished to watch, but with better video quality, which is in HD. This second embodiment also allows to identify new television services, and therefore new LCNs, which are added on the air by the broadcasters. In this case every predetermined time period, the apparatus 1 performs a scanning of available television services broadcast and controls whether there are new LCNs with respect to those that had stored in a previous scan, always starting from the television program name.

In case that were not available LCN numbers in the television signal, because the television receiver apparatus 1 is tuned on satellite signals, operates simply by not storing the LCN but instead it searches the television services according to their carrier frequency and video and audio PID. In this case the table 17 could contain the carrier frequency values and related video and audio PID of the television service instead of the LCN numbers.

With reference to Fig 5, the method according to the present invention provides at step 20 to select, through a control device 10, a certain available television program, and its related television service identified through a LCN, or a carrier frequency and a PID. Such selection is expected also in the process of "zapping" using the keys "+" and "-" of the control device 10.

Next, at step 21, the method provides to verify if said a certain television program selected by an user and its related television service, is broadcast on a different LCN (Logical Channel Numbering), or on a different carrier frequency and a PID, (Packet IDentifier) with respect to the one selected by the user. More in detail, such verification is performed through the central processor 5 and the tuning and demodulating unit 2.

At step 23, if the television service selected, and its relating current television program, is not available on different LCN, or carrier frequency and PID, then the apparatus 1 stays tuned to said television service selected.

If the check results in finding at least one LCN, or carrier frequency and PID, in step 25, the apparatus 1 performs a comparison based on video signal coding system among the original television service selected and those found to determine which has the best video quality. In particular, the operation of comparison is performed through the central processor 5 and the video circuit 4.

Next, at step 27, the apparatus 1 is automatically tuned to the LCN, or carrier frequency and PID, of the television service with the best video quality available. Then, this television service is displayed on the screen 7 of the apparatus 1.

It must be pointed out that the method according to the present invention can be implemented through a computer product which can be loaded into the memory 8 of the apparatus 1 and which comprises portions of software code adapted to implement the method by using existing hardware.

A first advantage of the method and the apparatus according to the present invention is that a user has the possibility of watching television programs with the best quality available in a "user-friendly" manner, also in presence of a mix of programs transmitted with different standards.

A second advantage of the method and the apparatus according to the invention is to allow the user to enjoy automatically the better quality of a television program when they are transmitted with enhanced television standards.

A third advantage of the method and the apparatus according to the invention is that a user can watch automatically the best quality of a television program, even if he/she doesn't know how to find it.

The method and the apparatus for selecting programs and their related television services and for displaying them on or through a television receiver, may be subject to many possible variations without departing from the novelty spirit of the inventive idea; it is also clear that in the practical implementation of the invention the illustrated details may have different shapes or be replaced with other technically equivalent elements.

For example, the method and the apparatus for selecting television programs and their related services and for displaying them on or through a television receiver may be expected that the switching to the television service having the best video quality is confirmed by the user.

In particular, it would be possible to provide the appearance of a frame (or pop-up screen) on the screen 7 of the apparatus 1, maybe superimposed with respect to the television signal, which alerts the user of the availability, on a different LCN, or carrier frequency and PID, of the same current television program, but with better video quality. The user then has the opportunity to choose, by means of the remote control device 10, to display the television program with the best video quality/standard, or continue to watch the current television program.

Another possible variant would be to provide in the apparatus 1 a second tuning and demodulating unit and a second video circuit that respectively perform a search of a television service, and its relating television program, with different LCN, or different carrier frequency and PID, and an estimate of the video coding system, in parallel to the vision of a current television program. This type of search is performed in background, because the user can continue to watch his current content related to the television program, without waiting for the end of the search procedure of the television service with the best video quality. In this way, if the user has selected a service with less video quality, when a better one is found the apparatus 1 switches automatically on this last one.

Another important embodiment of the present invention is related to the situation of broadcasting television services all around the world. For instance, while in many countries there is an association between the coding systems and the definition of the contents delivered by different services (for instance MPEG2 is associated to the standard definition and MPEG4 is associated to the High Definition), in other countries the above relationship between the coding standard type and the definition of the service's contents (i.e. the video quality) is not so strict. In fact it is possible to find services broadcast with HD quality, but coded with the MPEG2 standard.

In this situation it is possible to implement an additional embodiment of the present invention working also in this case.

This embodiment is based on the fact that the quality of the broadcast video service (i.e. SD, or HD, or UHD) can be determined in a different way, no more making a fixed relationship between the video coding systems and the definition of the different services.

In fact in the digital streaming of television services, among other data, there are provided the so called Service Information (SI) data in order that the user can be provided with information to assist him/her in selection of services and/or events contained within the bitstream and so that the receiver can automatically configure itself for the selected service. Therefore the Service Information data supply the receiver for instance with the information about the name of the services and their quality (SD, HD, UHD) in this way: BBC HD, SRF1 HD, ORF 2 HD, Arte HD, etc. Normally the television receiver apparatus 1 extracts this information for the purpose of indicating on the screen 7 the name of the service selected by the user or as data for identifying the service in the EPG. This information can be used in accordance to the present invention also for creating in the memory 8 a table like the one displayed in the Fig. 6.

In fact as explained before, under the control of the central processor 5 at the time of the installation of the television receiver apparatus 1, when all the available services are searched, the table of Fig. 6 can be created and consequently it can be established the relationship with services having the same name, but transmitting contents with SD, or HD, or UHD video quality. In other words, this embodiment provides to obtain the video quality information from the television service name.

Therefore when the user is selecting an ID Code 13 (related to the keys) for tuning a certain television service, the central processor 5 locks into the table of figure 6 and, if there is another service (identified by the SI information) corresponding to the service selected by the user, but broadcast with better definition, automatically switches the tuning of the television receiver apparatus 1 into the service transmitting the same content, but with the best video definition/quality available. Of course, if for any reasons the user doesn't like it, this automatic switching can be denied.

The feature described above can be obtained also starting from the EPG facility, selecting the name of a certain program that the user likes to watch. This is a useful feature especially in those cases when a network has different services in SD, but only one in HD or UHD. In this case this network concentrates on one service only the contents in HD or UHD. Therefore when the user is selecting a service that is providing contents in SD, it is not said that the actual program on this service is broadcast also on a different service in HD or UHD quality. Therefore when the user selects a program, starting from the EPG it is possible to ascertain if on the HD or UHD service of the same network the same program is available. In the positive case the central processor 5 switches the tuning of the television receiver apparatus 1 into the HD or UDH service (which one with the best video quality is available), otherwise remains tuned on the service having SD contents (or HD contents if the UHD is not available), because the program selected from the EPG is not transmitted actually with a better definition HD or UHD.

It can therefore be easily understood that the present invention is not limited to a method and an apparatus for selecting television programs and their related services and for displaying them on or through a television receiver, but may be subject to many modifications, improvements or replacements of equivalent parts and elements without departing from the novelty spirit of the inventive idea, as clearly specified in the following claims.

Claims

1. A method for selecting television programs and their related services and for displaying them on or through a television receiver apparatus (1), said method comprising the steps of:

a) selecting, through a control device (10), a certain available television program and its related television service associated to a certain service identifier;

b) verifying, through a central processor (5) and a tuning and demodulating unit (2), if said certain television program selected by an user and its related television service, is broadcast with a different service identifier, with respect to the television service selected as a consequence of the program chosen by the user;

c) controlling, through said central processor (5) and a video circuit (4) which television service, among those found services that transmit said certain television program selected by the user, has the best video quality available;

d) displaying on a screen (7) said certain television program selected by the user, and its related television service, having said best video quality.

2. A method according to claim 1, wherein said service identifier can comprise a set of data that are able to determine a specific television service, namely a LCN data (Logical Channel Numbering) or a Service ID derived from Service Information (SI) tables or a pair of data about a carrier frequency and Program IDentifier (PID) of said television service.

3. A method according to claim 1, wherein is provided a step of creating an association between a name of said television service and at least one said service identifier, said association bringing information related to its video quality, said association being stored in a memory (8) and read out from it when the step b) has to be performed.

4. A method according to claim 1, wherein said step b) provides the search, in an EPG (15) (Electronic Program Guide) available on said television receiver apparatus (1), of a text string of the name of said television program selected by the user, identifying a television service having, with respect to the television service selected as a consequence of the program chosen by the user, a different service identifier.

5. A method according to claim 4, wherein said television program name sought corresponds to a different television service having a different said service identifier and for each said service identifier is associated said information related to a video quality of said different television service.

6. A method according to one or more of the preceding claims, wherein a television service name is derived from PSI tables (Program Specific Information), included in a transport stream and used for creating said association between said television service and at least one said service identifier.

7. A method according to claim 6, wherein said video quality is derived from said television service name.

8. A method according to claim 1, wherein said step c) provides of obtaining an information about a coding system (19) of a television signal of said television service, by decoding system type performed by said video circuit (4).

9. A method according to claim 8, wherein said information about said coding system (19) is stored in said memory (8) through said central processor (5) and sent from said video circuit (4) to said central processor (5).

10. A method according to claim 1, wherein before said step d), said method comprises the step of displaying a frame, in particular a pop-up screen, on said screen (7) which alerts a user that a current television program of said television service is available with said best video quality, asking the user a confirmation to switch said television service with said best video quality.

11. A method according to claim 1 , wherein said step d) is performed in an automatic manner without the need of confirmation input by the user.

12. A television signal receiver apparatus (1) for selecting television programs and their related services and for displaying them on a screen (7), internal or external to said apparatus (1), said apparatus (1) comprising:

- at least one input (3) for receiving television signals of said television services;

- a tuning and demodulating unit (2) for tuning and demodulating said television signal;

- a video circuit (4) for video decoding of said television signal;

- a memory (8) for storing data;

- a central processor (5) adapted to control the operation of the above-mentioned elements;

characterized in that: - a control device (10) is provided for selecting a certain available television program and its related television service associated to a certain service identifier;

- said central processor (5) and a tuning and demodulating unit (2) verify if said certain television program selected by an user and its related television service, is broadcast on a different service identifier, with respect to the television service selected as a consequence of the program chosen by the user;

- said central processor (5) and said video circuit (4) control which television service, among those found services that transmit said certain television program selected by the user, has the best video quality available;

- said apparatus (1) displays on a screen (7) said television program selected by the user, and its related television service, having said best video quality available.

13. An apparatus according to claim 12, wherein said central processor (5) reads, from a memory (8), a name of said television service and at least one said service identifier bringing the information related to its video quality.

14. An apparatus according to claim 12, wherein said central processor (5) searches in an EPG (15) (Electronic Program Guide), available on said television receiver apparatus (1), a text string of the name of said television program selected by the user, identifying a television service having, with respect to the television service selected as a consequence of the program chosen by the user, a different service identifier.

15. An apparatus according to claim 12, wherein said central processor (5) obtains an information about a coding system (19) of said television signal regarding said television service, by the decoding system type performed by said video circuit (4).

16. An apparatus according to claim 15, wherein said central processor (5) stores said information about said coding system (19) in said memory (8).

17. An apparatus according to claim 16, wherein said video circuit (4) sends said information about said coding system (19) from itself to said central processor (5).

18. An apparatus according to one or more of the preceding claims, wherein said apparatus (1) further comprises a second tuning and demodulating unit and a second video circuit for searching in background said television service, and its relating television program, having said best video quality available.

19. A computer product which can be loaded into a memory (8) of said apparatus (1), comprising portions of software code adapted to implement the method according to one or more of claims 1 to 11.