WO2002078351A1

WO2002078351A1 - Method and device for transmitting video and/or audio data

Info

Publication number: WO2002078351A1
Application number: PCT/DE2002/001139
Authority: WO
Inventors: Daniel Hammer
Original assignee: Voxar Ag
Priority date: 2001-03-27
Filing date: 2002-03-27
Publication date: 2002-10-03
Also published as: DE10291291D2

Abstract

The invention relates to a method for transmitting video and/or audio data, whereby areas within the video and/or audio data are prioritised according to at least one predetermined or predeterminable criterion. The invention also relates to a device for transmitting video and/or audio data, comprising user data input devices for inputting image and/or audio data and transmission data output devices for outputting image and/or audio data to a communications network in order to connect to a communications device of another communication user. Prioritising devices are located between the user data input devices and the transmission data output devices. Said prioritising devices have processing units, which assign different priorities to individual image and/or audio data areas and in addition are configured for outputting an image and/or audio data area, depending on its priority, unprocessed or with a reduced dataset to the transmission data output devices for transmission.

Description

Method and device for transmitting video and / or audio data

description

The invention relates to a method and a device for transmitting video and / or audio data.

When transmitting video and / or audio data, for example in remote telephony, there is the problem that with the specified line and / or radio capacities for transmissions, a relatively large amount of information and data must be transmitted between two communication participants. In particular, the amount of information and data to be transmitted is variable over time, for example when there are pauses in speech. Furthermore, for example, still images would not have to be transferred continuously, but a one-time transfer would suffice until a change in the image occurs again. The aforementioned requirements would, on the one hand, require the provision of line and / or radio capacities for transmissions of the maximum information and data occurring per unit of time, without these capacities being constantly needed and used. On the other hand, there would be transmission bottlenecks if the line and / or radio capacities could not transmit the maximum information and data occurring per unit of time.

In order to remedy these disadvantages, the present invention aims to provide a method and a device for the optimized transmission of video and / or audio data.

This goal is achieved with a method and a device for the optimized transmission of video and / or audio data according to the corresponding independent claims.

In the context of the present invention, so-called smart scaling or smart sizing is used in such ner drives and devices in order to create the optimized transmission of video and / or audio data, in particular as a function of an available bandwidth of a transmission channel. The method according to the invention and the corresponding device for the transmission of video and / or audio data optimized by the invention is to be used with particular preference for, but not limited to, telephony. Further applications can be seen, for example, in the field of video conferencing.

In methods and devices according to the invention, image or audio data coming from a video or audio source are prioritized before and / or during their transmission. This prioritization takes place according to at least one predetermined or predeterminable criterion within or within the framework of the corresponding information contained in the image or audio data. The prioritization determines which image and / or audio data are transmitted, the data with the highest priority being preferably transmitted.

A predetermined or predeterminable criterion is preferably a facial area recognition.

The method according to the invention, in which the prioritization takes place according to at least one predetermined or predeterminable criterion, has one or more of the steps specified below within the scope of preferred configurations, which the device solutions of the present invention also do justice to: a) the prioritization within the image and / or audio data is carried out before and / or during the transmission, b) the prioritization can be changed during the transmission, c) the bandwidth available determines how much image and / or audio data is transmitted in what quality, d) by the prioritization determines which image and / or audio data are transmitted, the data with the highest priority being preferably transmitted, e) the prioritization determines the quality in which image and / or audio data are transmitted, the highest prioritized image and audio data gr Larger shares of the available bandwidth are granted, and / or f) the prioritization and the amount of the bandwidth determine whether and in what quality subordinate or "less prioritized" image and / or audio data are transmitted.

Further refinements and developments of the invention that are preferred in terms of the method and implemented accordingly in devices are given below: a) Detection and tracking of the face area (face tracking) in combination with a reduction in the screen resolution, b) a resolution reduction depending on the available bandwidth is preset or variable or optimized according to the respective possibility, c) a reduction of the image, in the way, that the recorded and processed information decreases towards the outer edge of the image, d) a radial grading, preferably oriented on the face area, and / or e) a concentration on the face area.

The invention also provides a device for the transmission of video and / or audio data, with subscriber data input devices for inputting image and / or audio data and transmission data output devices for outputting image and / or audio data to a communication network for the purpose of connection to a communication device of another communication subscriber, wherein prioritization devices are arranged between the subscriber data input devices and the transmission data output devices, which have processing devices which assign different priorities to the individual image and / or audio data areas and are further designed to depend on an image and / or audio data area unprocessed from its priority or output with a reduced amount of data to the transmission data output devices for transmission.

A preferred further development of this consists in the processing devices being designed alternatively or in combinations for carrying out different prioritizations according to different criteria.

Another preferred embodiment provides that the prioritization devices contain memories in which program and / or data information for at least one prioritization or their implementation is stored, and that the processing devices include the program and / or data information as a function of specified requirements retrieve from the stores or have them made available from there.

As an alternative or in addition, it can further be provided that the prioritization devices contain monitoring devices that perform the performance and / or quality of the communication network, in particular its available transmission or signal bandwidth, and / or the communication device of a communication partner, preferably as a function of changes as a function of changes to more than a predetermined extent or check depending on preset time intervals and at least output the result to the processing devices in the event of detected changes, and that the processing devices then use suitable criteria based on corresponding information in the memories and prioritize image and / or or initiate and carry out audio data areas.

A device according to the invention for the transmission of video and / or audio data can also be further developed in that manual selection devices are included which enable the user to preset individual priorities or combinations thereof or to set current or permanent default values for certain connections.

Further preferred and advantageous configurations of the invention result from the dependent claims and their combinations as well as from the entire available documents.

On the basis of the exemplary embodiments and application examples described below and shown in the drawings, the invention is merely explained in more detail by way of example. The drawing shows:

1 shows a sample image with prioritized areas transmitted with a first predetermined bandwidth, and

FIG. 2 shows the sample image from FIG. 1 with the same prioritized areas transmitted with a second bandwidth, which is reduced compared to the bandwidth in the example according to FIG. 1.

For the exemplary embodiment it is assumed that videophone communication takes place between two people. Two videophones are used for this. Such videophones work bidirectionally. For the example, the transmission of the image of a person from, for this case, their transmitting devices in the corresponding videophone to the corresponding receiving devices in the videophone of their communication partner is selected as an example. The basic equipment requirements and related technical methods for video telephony, as well as for video conferences, are generally known and are not directly the subject of the present invention, so that detailed explanations thereof are omitted here. In FIG. 1, prioritized areas 1 of a transmitted image 2 in the form of the head 3 and the upper body 4 of a recorded person 5 are schematically represented by borders 6 in the form of routes. On the basis of a predetermined bandwidth for a transmission of the image 2 from, for example, one video telephone (not shown) to another, background information 7 in the form of captured sections is also transmitted from a shelf 8 and an image 9.

For FIG. 2 it is now assumed that the bandwidth for the transmission has been reduced compared to the transmission of the image 2 according to FIG. 1. The illustration shows that the prioritized areas 1, i.e. in the example, the head 2 and the upper body 4 of the person 5 taken are clearly shown in the image 2, but the background information 7 has been neglected. The shelf 8 and the image 9 do not belong to the prioritized areas 1 and their data have been reduced in accordance with the reduction in the bandwidth of the data transmission, for example to replacement color areas. In the Fig.

I and 2 show yet another prioritized area 10, which, however, has a lower priority than the prioritized area 1, but a higher priority than the background information 7. This further prioritized area 10, which is merely an example of the tie

I I and its surroundings, is therefore subordinate to the prioritized area 1, which has the highest priority. Accordingly, in the transmission according to FIG. 2, a lower resolution is selected in the further prioritized area 10.

As a further exemplary prioritized area 1, the part 12 eye-nose-mouth of the person 5 is symbolized by a fitted triangle 13 in FIGS. 1 and 2.

The data that do not belong to the prioritized areas 1 can either be completely neglected, ie they are not displayed at the receiver, or they are initially transmitted and stored in the receiver device, so that they can be displayed constantly without being transmitted further have to. The use of prioritized areas thus enables the essential data and thus information to be transmitted even with a smaller transmission bandwidth, without having to accept losses in the transmission speed, for example. Depending on the available bandwidth of a transmission channel for the image and audio data, the higher priority image and audio data are transmitted to the receiver. With a high available bandwidth, the more subordinate video or image and audio data are transmitted. When the bandwidth is low and / or fluctuating, the focus is on the highest priority image and audio data. The invention is not restricted to an application in the field of video telephony. In particular, the ner rides and north directions according to the present invention can also be used advantageously, for example, at nideoconferences. Furthermore, prioritization can be carried out not only for the image data, but also for the audio data.

The method and the device according to the present invention are based on a customary communication method or system, such as for example in video telephony or in video conferences. A first communication participant uses image and audio data in e.g. entered a videophone, for which camera and microphone devices are used, which are generally to be referred to as subscriber data input devices of the communication device in the form of the videophone. The image and audio data are then output by means of transmission data output devices to a communication network via which there is a connection to a communication device of the communication partner or just another communication participant. The connection itself is established via suitable devices which are known to the person skilled in the art and are not specifically the subject of the present invention, so that there is no need to go into this here.

The image and audio data of the first communication participant thus get from the communication network into the communication device of the communication partner, or more precisely into transmission data input devices in this communication device, which also has reception data output devices, such as in particular a screen and a loudspeaker, with which the transmitted image and audio data of the first communication participant can be seen and heard by his communication partner.

The communication network contains line and / or radio transmission devices by means of which image and audio data or generally communication data are transmitted on so-called channels. This technology is also not a direct component of the present invention and can be selected from the available options within the scope of specialist skill and knowledge, so that a detailed discussion in the context of this description is not necessary. The same applies to the precise methods and devices for such data transmission types, wherein a certain signal or data bandwidth is used for data transmission within a transmission channel. This bandwidth can be preset or variable depending on the quality of a connection or the load on the channel, for example. At this point the present invention attacks, but not on the technology of the communication network itself and particular not on the transmission channels or the signal or data bandwidths or their controls, but on the type and / or amount of data to be transmitted.

Continuing the communication method or system explained above by way of example, the invention provides that the communication device of the first communication subscriber has prioritization devices, by means of which so-called prioritized areas within the image and audio data are recorded, which are recorded by the first communication subscriber using the subscriber data. Input devices of his communication device were obtained. The prioritization devices are thus provided between the subscriber data input devices and the transmission data output devices in the communication device.

The prioritization devices contain at least processing devices which are operated in a predetermined manner, e.g. Using an electronic program sequence, for example within the image data of a snapshot of the first communication participant, determine or define priority areas. Such a snapshot is also called a frame.

The given prioritization method depends on at least one criterion. Such a criterion can e.g. the mouth, the part eye-nose-mouth, the face, the head or the upper body of the first communication participant. The criterion belonging to a prioritization method to be carried out can be permanently set or built into the prioritization devices and thus the communication device. However, it is also possible to choose freely or depending on e.g. a maximum possible bandwidth to provide various criteria for use by the prioritization devices. For this purpose, memory must then be provided in the prioritization devices or assigned to them, in which data and information for a respective electronic program sequence are stored and available for the processing devices.

The specific implementation of the prioritization, or in other words, the specific application of at least one criterion in accordance with the selected or set method of prioritization can be carried out using known image processing and processing techniques. It is not necessary to go into these techniques precisely, since a person skilled in the art can easily select and combine suitable image processing and processing techniques. Depending on the technology used, the required size and performance of the processing equipment and the memory are then automatically determined. Insofar as only a reference to the image data has been described, this does not limit the present invention to this. A corresponding treatment of the audio data is readily apparent to the person skilled in the art even without a separate representation.

The method according to the invention, in which the prioritization takes place according to at least one predetermined or predeterminable criterion, has, in the context of preferred configurations, one or more of the steps specified below, from which corresponding device configurations also result:

a) The prioritization within the image and / or audio data is carried out before and / or during the transmission. Prioritization prior to transmission produces, so to speak, a "filter" for the image and / or audio data that is currently set once for a communication connection that is established or to be established. Continuous prioritization during transmission enables this "filter" to be constantly updated, so that changed circumstances in the transmitted image and / or sound as well as in the technical process of the connection can be taken into account.

b) The prioritization can be changed during the transmission. According to the second aspect of point a) above, this enables the prioritization to be constantly updated, so that changed circumstances in the transmitted image and / or sound as well as in the technical process of the connection can be taken into account.

c) The available bandwidth determines how much image and / or audio data is transmitted and in what quality. An automatism is thus provided in order to utilize the current maximum possibilities of the connection in each case. In addition to the processing devices and the memories, the prioritization devices also contain monitoring devices which monitor the performance and quality of the connection, in particular the available bandwidth, via the communication network as a function of changes, as a function of changes to a predetermined extent or as a function of Check the preset time intervals and at least output the result to the processing equipment if changes are detected. The latter then use suitable criteria based on the corresponding information in the memories, depending on the changed connection parameters. How much image and / or audio data is transmitted in which quality not only affects the fact whether respective data is transmitted at all, but also the resolution and thus the amount of data that individual image areas are transmitted. Examples of reduced resolutions result from the comparison of FIG. 1 and 2 in the picture details of the tie 11 and the background information 7 (shelf 8 and picture 9), where in the transmission according to FIG. 2 in the further prioritized area 10 with the tie 11 a lower resolution than in the prioritized area 1 is selected , and the background information 7 was in turn transmitted with a lower resolution than the further prioritized area 10. This ensures optimal utilization of the connection options in an automated manner.

d) The prioritization determines which image and / or audio data are transmitted, and the image and / or audio data with the highest priority are preferably transmitted. This procedure or device-based control ensures that the most important data (e.g. the mouth, the part of the eye-Νase-mouth, the face, the head or the torso of the first communication participant) are transmitted and that less important data (e.g. background images) are neglected or not transmitted. Instead of the less important data, either nothing can be reproduced at the receiver (e.g. screen black or white or in a basic color) or a standard background or a previously transmitted background. This means that a maximum amount of information is transmitted in the transmission channel even when the bandwidth is reduced or reduced.

e) The prioritization determines the quality in which image and / or audio data are transmitted, the highest priority image and / or audio data being granted larger shares of the available bandwidth, or in other words, the highest prioritized image and / or audio data (e.g. the mouth, the part of the eye-Νase-mouth, the face, the head or the upper body of the first communication participant) with higher to irin to maximum quality and subordinate image and / or audio data (e.g. background images ) are transmitted with lower quality up to the complete omission. This procedure or device-based control ensures that the most important data (e.g. the mouth, the part of the eye-Νase-mouth, the face, the head or the upper body of the first communication participant) in maximum or complete quality, such as resolution, if it it is image data that are transmitted and less important data (for example background information 7) with lower quality or analog image resolution are transmitted. This can be seen, for example, when comparing FIGS. 1 and 2. In FIG. 2, the image data of, for example, the shelf 8 according to the resolution in the illustration in FIG. 1 on the right-hand edge of the image are replaced by color areas which are represented by a smaller amount of data than that Amount of data required to display the image of the shelf 8 itself in FIG. 1. A further example of reduced resolutions results from the comparison of FIGS. 1 and 2 in the picture details of the tie 11, where in the transmission according to FIG. 2 in the further prioritized area 10 with the tie 11 a lower resolution than in the prioritized one Area 1 is selected. The background information 7 was in turn transmitted with a lower resolution than the further prioritized area 10. This means that a maximum amount of information is transmitted in the transmission channel even when the bandwidth is reduced or reduced.

f) The prioritization and the amount of the bandwidth determine whether and in what quality subordinate or "less prioritized" image and / or audio data are transmitted. In addition to the processing devices and the memories, the prioritization devices also contain monitoring devices which monitor the performance and quality of the connection, in particular the available bandwidth, via the communication network as a function of changes, as a function of changes in more than a predetermined scope or as a function of preset time intervals Check and output the result to the processing equipment at least when changes are detected. The latter then use suitable criteria based on the corresponding information in the memories, depending on the changed connection parameters. This ensures optimal use of the connection options in an automated manner. This procedure or device-based control ensures that the most important data (e.g. the mouth, the part of the eye-nose-mouth, the face, the head or the upper body of the first communication participant) are transmitted with high quality and in particular completely, and less important data (e.g. background representations) are transmitted with lower quality, neglected or not transmitted. Instead of the less important data, either the data record with a lower resolution (including replacement color areas), nothing (e.g. screen black or white or in a basic color) or a standard background or a previously transmitted background can be reproduced at the receiver. This means that a maximum amount of information is transmitted in the transmission channel even when the bandwidth is reduced or reduced.

Further refinements and developments of the invention preferred in terms of device and method are given below: a) Detection and tracking, for example of the face area (face tracking) in combination with a reduction in the image or screen resolution: using known image processing and processing techniques in particular, the processing devices preferably capture the face or the head or parts thereof in real time within the image data from the communication participant. The corresponding shape is then preferably tracked in real time. Several individual shapes, such as for the mouth, the eyes, the nose, the part eye-nose-mouth, the face, the head or the upper body of the first communication participant, can be detected and tracked. The separate recording and tracking also enables different prioritizations for the shapes of, for example, mouth, eyes, nose, batch of eyes-nose-mouth, face, head or upper body. Details of this are stored in the memories and are queried from there by the processing facilities or made available there. The processing devices set different image resolutions for the individual characters in accordance with individual concrete prioritizations or associated criteria. As a result, the amount of data in a single image or frame is reduced, so that an optimized image can be transmitted even with a reduced bandwidth, in particular with optimal to maximum resolution, at least in the most highly prioritized areas of the image data.

b) A resolution reduction for the image and / or audio data depending on the available bandwidth is preset or variable or optimized according to the respective possibility: Through these process variants and their implementations by means of suitable controls in the processing devices and monitoring devices as well as the data required for their operation in the Operating modes are implemented. A predetermined resolution depending on available bandwidth values for respective prioritizations results in an automated and step-by-step optimization of the data reproduced at the receiver, taking into account the current performance and quality of the communication network. A variability can be used with regard to the size of the available bandwidth values and / or the resolution, so that a quasi-continuous adaptation of the transmission to the performance and quality of the communication network can take place.

An optimized resolution or resolution reduction is to be understood here to mean that other criteria are also taken into account. For example, these can also contain the lowest possible load on the communication network, in that, for example, background image data, for example ascertained as a result of detection and tracking, for example of the face area (face tracking), is fundamentally with a lower resolution are transmitted than image data of the facial area. In this way, consideration for the availability of the communication network for as many users as possible is achieved. It can advantageously be provided that the optimization of the resolution or reduction in resolution takes place as a function of, in particular, a customary time of day or current utilization of the communication network, which can be “learned from the communication network” via the monitoring devices and can thus be determined for controlling the processing devices. Further criteria for an optimized resolution or resolution reduction are, for example, device specifications, which means that transmission with a higher resolution than the receiver device can display is not carried out, which would otherwise itself have to / have to convert the received data into data representative of the lower displayable resolution. Still further criteria for an optimized resolution or reduction in resolution can consist in the contents of the image and audio data, which are recorded via the subscriber data input devices of the communication device. If the user is close to these subscriber data input devices, such as a camera for inputting the image data, larger uniform areas can be expected for which lower resolutions can be selected. If the even areas are smaller, a higher resolution would be used. The prioritization according to such criteria would thus enable savings in transmission effort with uniform areas in the image to be transmitted.

c) A reduction in the image to be transmitted or more precisely the data representing the latter in such a way that the acquired and processed information on the outside edge of the image decreases in one step or in several steps or continuously linearly or according to an intensity curve: the prioritization preferably in this Fall the center of the picture. Areas of the image that are further out are secondary. This takes advantage of the fact that essentials in a picture, such as the head or face of a person, are as far as possible in the center of the picture. In addition to or instead of the resolution, the color depth can also be reduced from the center of the image to the outside.

d) A radial grading, preferably based on the facial area: In contrast to the variant according to item c) above, the resolution or color depth is not preset in one step or in several steps or continuously linearly or according to an intensity curve, but is not preset from the outside, but rather based on an actually recorded facial area that does not necessarily have to be in the center of the image. A facial area recognition and tracking in accordance with point a) above is carried out in terms of the further device and method. preferred refinements and developments of the invention. In this case, prioritization favors the user face in the image as the center. Areas of the image outside the face are of secondary importance. In addition to or instead of the resolution, the color depth can also be reduced from the face to the outside.

e) Concentration on the facial area: This variant assumes that all image components outside of the user's face are irrelevant. In this case, facial area detection and tracking is used in accordance with point a) above of the further refinements and developments of the invention preferred in terms of device and method. In this prioritization, background information 7 is hidden or neglected in stages or completely before the image transmission.

Another priority-dependent saving possibility in the transmission of the image data can be seen in the reduction in the recognized and transmitted color data for each or individual pixels or image areas. This processing can be used for any type of priority area, regardless of the selection criterion.

In particular, within the scope of the present invention, different prioritizations or, in other words, priority criteria can be combined, connected in series or nested. The processing devices are responsible for this, including appropriate program and / or data information from the memories in the prioritization devices.

The communication devices, which in the sense of the present invention represent a device for the transmission of video and / or audio data, can also have manual selection devices which enable the user to preset individual priorities or combinations thereof or for current connections as current or permanent Set default. Known peculiarities of receiver devices, such as, for example, lower playback resolution options, location-related circumstances, such as background volume and / or lighting at one's own or communication partner device location, and others can thus be taken into account. In addition to the possibility of manually setting priorities, such settings can also be made automatically. A transmission of the respective circumstances (peculiarities of receiver devices, background volume and / or lighting) from each receiving device is suitable, for example, to take into account the criteria given above by way of example. With regard to the prioritization of audio data, possible criteria are the volume, whereby background noise can be suppressed or neglected, frequency ranges, with which the ranges customary for human speech, for example, can be preferred, or the volume dynamics, which can be damped. With these criteria, for example, depending on the corresponding prioritization, a reduction in the data transmission effort to adapt to reduced bandwidths in the transmission channel can be achieved.

The invention is only illustrated by way of example in the description and in the drawings, and is not limited thereto, but includes all variations, modifications, substitutions and combinations which the person skilled in the art will understand in the introduction, in particular within the scope of the claims and the general representations this description and the description of the exemplary embodiments and their representations in the drawing and can combine with his professional knowledge and the prior art. In particular, all individual features and configuration options of the invention and its exemplary embodiments can be combined.

Claims

Expectations

1. A method for transmitting video and / or audio data, wherein areas within the video and / or audio data are prioritized according to at least one predetermined or predeterminable criterion.

2. The method according to spoke 1, wherein a criterion is a facial area recognition.

3. The method according to claim 1 or 2, wherein a) the prioritization within the image and / or audio data is carried out before and / or during the transmission, b) the prioritization can be changed during the transmission, c) determined by the available bandwidth how much image and / or audio data are transmitted in which quality, d) the prioritization determines which image and / or audio data are transmitted, the highest-priority data being preferably transmitted, e) the prioritization the quality in which image and / or audio data are transmitted, the highest-priority image and audio data being granted larger shares of the available bandwidth, and / or f) being determined by the prioritization and the amount of the bandwidth whether and in what quality subordinate image and / or audio data are transmitted.

4. The method of claim 1, 2 or 3, wherein a) a detection and tracking of the face area (face tracking) is carried out in combination with a reduction in screen resolution, b) a resolution reduction depending on the available bandwidth is preset or variable or optimized the respective possibility is carried out c) a reduction of the image in such a way that the recorded and processed information decreases towards the outer edge of the image, d) a radial grading, preferably based on the facial area, and / or e) a concentration on the facial area becomes.

5. Device for transmitting video and / or audio data, with subscriber data input devices for inputting image and / or audio data and transmission data output devices for outputting image and / or audio data to a communication network for the purpose of connection to a communication device of another communication subscriber , Priority devices are arranged between the subscriber data input devices and the transmission data output devices, which have processing devices which assign different priorities to the individual image and / or audio data areas and are further designed to provide an image and / or audio data area depending on its priority output unprocessed or with a reduced amount of data to the transmission data output devices for transmission.

6. The device for transmitting video and / or audio data according to claim 5, wherein the processing devices are designed to carry out different prioritizations according to different criteria, alternatively or in combinations.

7. The apparatus for transmitting video and / or audio data according to claim 5 or 6, wherein the prioritization devices contain memories in which program and / or data information for at least one prioritization or their implementation are stored, and wherein the processing devices the program and / or retrieve data information from the memories or receive it from there, depending on specified requirements.

8. Device for the transmission of video and / or audio data according to one of claims 5 to 7, wherein the prioritization devices contain monitoring devices, the performance and / or quality of the communication network, in particular its available transmission or signal bandwidth, and / or the communication device Communication partner, preferably depending on changes, depending on changes to more than a predetermined extent or depending on preset time intervals and at least when determined output the result to the processing devices, and the processing devices then, depending on the changes ascertained, use suitable criteria, if necessary, on the basis of corresponding information in the memories and initiate and carry out prioritization of image and / or audio data areas.

9. Device for the transmission of video and / or audio data according to one of claims 5 to 8, wherein manual selection devices are included which allow the user to preset individual priorities or combinations thereof or to set current or permanent as default for certain connections.