WO2015088407A1

WO2015088407A1 - Method and a network node for video communication services

Info

Publication number: WO2015088407A1
Application number: PCT/SE2013/051492
Authority: WO
Inventors: Mats Folkesson; Valentin Kulyk; Gunilla BERNDTSSON
Original assignee: Telefonaktiebolaget L M Ericsson (Publ)
Priority date: 2013-12-12
Filing date: 2013-12-12
Publication date: 2015-06-18

Abstract

A method performed by a network node (110) for enabling a video communication service between two or more user equipments (121-125). The network node (110) receives an indication of the quality rendering capability of the user equipment from each of the user equipments (121-125). The network node (110) also determines a video quality range of the video communication service between the user equipments (121-125), wherein the highest video quality of the range is determined by the highest video quality of the user equipment with the lowest video quality rendering capability and the lowest video quality of the range is determined by the lowest video quality of the user equipment with the highest video quality rendering capability. Then, the network node (110) enables the video communication service based on the determined video quality range. A network node (103) for performing the method is also provided.

Description

METHOD AND A NETWORK NODE FOR VIDEO COMMUNICATION SERVICES

TECHNICAL FIELD

Embodiments herein relate to the area of video communication services in a communications network. In particular, embodiments herein relate to enabling video communication services to user equipments in the communications network.

BACKGROUND

Video communication services are commonly used by multiple parties to participate simultaneously in a real-time multi-party communication session, such as, e.g. an audio-video conference.

It follows that during such a video communication session of video communication services, the parties involved in the session can use different devices having very different capabilities. The different devices may, for example, have different hardware

configurations, large or small screens, different processing powers, etc. This means that there may be large differences in which level of video quality that may be usefully or suitably presented on each device. In addition, this is very evident when a plurality of windows that are displaying videos from different parties, having devices of different capabilities in e.g. a video conference, appear side by side on the same screen.

At the same time, the different devices may also be connected via different data transport networks which each may have different capacities or capabilities. For example, one device may be a handheld mobile terminal comprising a small sized screen and being located in a wireless telecommunication network with limited bandwidth, while another device may be a TV with a large sized screen and being connected to a fibre-optical network with a very wide bandwidth. This also means that the difference in the level of video quality that may be sent to or from these devices may be very large, e.g. from or to a system or network node maintaining the video communication session using video mixing or directly to another device in case of a peer-to-peer connection. There are existing methods implemented in different types of systems and/or applications to e.g. decrease the impact of large variations in levels of video quality in communications networks, estimate and/or measure a certain video video quality and improve it, etc.

It is also well-known that human perception is limited by human visual system properties, such as, the maximum visual acuity resolution. Therefore, on display screens that have a small size, a high density of pixels may mask video compression artefacts that may be present in the video stream. Thus, video processing artefacts that are noticeable and disturbing on large screens are not visible to the same degree on smaller terminals, such as, e.g. smartphones and tablet computers.

However, there is currently no known suitable solution able to maintain a video communication service that achieves an experience of a stable video quality for all users irrespectively of the used device (i.e. a video quality that can be both presented by the device and perceived as good by the user), while at the same time not overusing or over- consuming the bandwidths of the data transport networks used by the video

communication service. This would improve video communication services to user equipments in a communications network.

SUMMARY

It is an object of embodiments herein to improve video communication services to user equipments in a communications network.

According to a first aspect of embodiments herein, the object is achieved by a method performed by a network node for enabling a video communication service between two or more user equipments in a communications network. The network node receives an indication of the quality rendering capability of the user equipment from each of the two or more user equipments. The network node also determines a video quality range of the video communication service between the two or more user equipments, wherein the highest video quality of the range is determined by the highest video quality of the user equipment with the lowest video quality rendering capability and the lowest video quality of the range is determined by the lowest video quality of the user equipment with the highest video quality rendering capability. Then, the network node enables the video communication service for two or more user equipments based on the determined video quality range. According to a second aspect of embodiments herein, the object is achieved by a network node for enabling a video communication service between two or more user equipments in a communications network. The network node is configured to receive an indication of the quality rendering capability of the user equipment from each of the two or more user equipments. The network node is also configured to determine a video quality range of the video communication service between the two or more user equipments, wherein the highest video quality of the range is determined by the highest video quality of the user equipment with the lowest video quality rendering capability and the lowest video quality of the range is determined by the lowest video quality of the user equipment with the highest video quality rendering capability. The network node is further configured to enable the video communication service for two or more user equipments based on the determined video quality range.

By enable the video communication service for two or more user equipments based on the determined video quality range as described above, a highest and a lowest video quality of a video communication session is provided which allows a stationary quality experience and optimal use of the transport networks capacity. For example, the limits of the video quality range are selected as a trade-off between network/processing capacity needed for achieving a good quality user experience on small screen devices and satisfactory good quality user experience on other larger screen devices. This is because it would not be good to deliver video quality levels that are higher than a device can videote, or a video quality that is too low and will result in a bad quality experience by some users.

The advantage is that users will experience less varying video quality of the video communication service system which improves the overall user experience, while the transport network will be used in more optimal way. This may be particularly useful when having large variations in levels of video quality that may be delivered and displayed in suitably in view of both user experience and communications network efficiency.

Hence, the video communication services to user equipments in a

communications network are improved herewith.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the embodiments will become readily apparent to those skilled in the art by the following detailed description of exemplary embodiments thereof with reference to the accompanying drawings, wherein:

Figure 1 is a schematic block diagram illustrating embodiments in a communications network.

Figure 2 is a schematic block diagram illustrating a display showing multiple

windows for different data streams of a video communication service. Figure 3 is a flowchart depicting embodiments of a method in a network node.

Figure 4 is a schematic diagram illustrating an example scenario for embodiments of a network node in a communications network.

Figure 5 is a block diagram depicting embodiments of a network node.

DETAILED DESCRIPTION

The figures are schematic and simplified for clarity, and they merely show details which are essential to the understanding of the embodiments presented herein, while other details have been left out. Throughout, the same reference numerals are used for identical or corresponding parts or steps.

Figure 1 depicts a communications network 100 in which embodiments herein may be implemented. In some embodiments, the communications network 100 is a data transport network that may comprise one or more cellular or wireless telecommunications networks, such as, e.g. a GSM, WCDMA, HSPA, LTE cellular network, and/or one or more data networks providing wired (i.e. non-wireless) access using, e.g. fibre-optics, DSL, Ethernet, modem or dial-up systems, etc. Via the communications network 100, a network node 110 may communicate with several different types of user equipments 121 , 122, 123, 124, 125 with different capabilities concerning video. It should here be noted that a wireless telecommunications networks normally has a small or limited available bandwidth, as opposed to a wired data network which may have a high or virtually un-limited available bandwidth.

The network node 110 may for example be a gateway or interface node for a video communication system in the communications network 100. The network node 1 10 may also be referred to as a network node or dedicated unit capable of performing media processing, such as, video conference setup, audio/video transcoding, audio/video mixing, etc., in the communications network 100.

The network node 110 is configured to provide video communication services to the user equipments 121-125. Video communication services may herein refer to any one or more of real-time communication services, live-streaming services and other end-user services that are deployed over a data transport network were a large variety of different types of devices are expected to consume the same video communication service simultaneously. This may comprise e.g. real-time multi-party conversations or sessions such as an audio video conference.

5 The user equipments 121-125 may e.g. be devices such as mobile terminals or wireless terminals, mobile phones, smartphones, computers (such as e.g. laptops, Personal Digital Assistants (PDAs) or tablet computers) with wireless capability, Machine to Machine (M2M) devices or any other radio network units capable to communicate with the network node 1 10 over a radio link in the communications network 100. Furthermore,

10 the user equipments 121-125 may also e.g. be devices such as terminals, computers (such as e.g. stationary computers, laptops, Personal Digital Assistants (PDAs) or tablet computers), TVs, large screen projectors or devices or any other data network units capable to communicate with the network node 110 over a wired communications link of a data network in the communications network 100.

15 Thus, the user equipments 121-125 may be different devices with different

hardware configurations (e.g. different video capture possibilities, different processor capabilities/processing powers, different display/screen sizes, etc.), different resolutions and frame rates, rendering capabilities, etc., making up the devices' video quality rendering capability. As part of the video communication services, each user equipment

20 121-125 may be configured to initially transmit its video quality rendering capability to the network node 110.

In the example shown in Figure 1 , a number of user equipments 121-125 with different capabilities and connections for the same conversational session are exemplified

25 to help illustrate the embodiments herein. Note that a frame rate of 25 frames per second is assumed in the example of Figure 1 for the sake of simplicity; however, other frame rates may also be used by the user equipments 121-125. It should further be noted that the example shown in Figure 1 presents an example of how video resolution, as one of many video quality aspects, may be used to define the video quality level. The

30 embodiments herein should however not be considered limited only to this particular video quality aspect.

A first user equipment 121 has a large sized 60 inch screen with a hardware configuration and rendering capabilities that support a first high definition video mode or resolution, such as, e.g. 1080p (also commonly referred to as Full High-Definition, FHD, 35 or BT.709). The first user equipment 121 may for example be a TV. The 1080p mode here refers to that it is defined by 1080 horizontal lines of vertical image display resolution and progressive scan; as opposed to, e.g. interlaced scan as is the case with the 1080i display standard. The term 1080p usually assumes a widescreen aspect ratio of 16:9, and implies a resolution of 1920x 1080 pixels, i.e. about 2.1 megapixels. Also, in this example, the first user equipment 121 may be configured to communicate with the network node 1 10 via a wired communications link of a data network in the communications network 100. Thus, the first user equipment 121 may transmit its video quality rendering capability to the network node 1 10 that may comprise indicators of at least both these aspects.

A second user equipment 122 has a small sized 4 inch screen with a hardware configuration and rendering capabilities that support a second high definition video mode or resolution, such as, e.g. 720p (also commonly referred to as High-Definition, HD). The second user equipment 122 may for example be a smartphone. The 720p mode here refers to that it is defined by 720 horizontal lines of vertical image display resolution and progressive scan. The term 720p usually assumes a widescreen aspect ratio of 16:9, and implies a resolution of 1280x720 pixels, i.e. about 0.9 megapixels. Also, in this example, the second user equipment 122 may be configured to communicate with the network node 1 10 via a radio link of a data network in the communications network 100. Thus, the second user equipment 122 may transmit its video quality rendering capability to the network node 1 10 that may comprise indicators of at least both these aspects.

A third user equipment 123 has a medium sized 17 inch screen with a hardware configuration and rendering capabilities that also support the first high definition video mode or resolution, such as, e.g. 1080p. The third user equipment 123 may for example be a laptop computer. Also, in this example, the third user equipment 123 may be configured to communicate with the network node 110 via a radio link of a data network in the communications network 100. Thus, the third user equipment 123 may transmit its indicators of at least both these aspects.

A fourth user equipment 124 has a small sized 4 inch screen with a hardware configuration and rendering capabilities that support another definition video mode or resolution, such as, e.g. 480p (which does not qualify as High-Definition, e.g. HD or FHD, but may be referred to as Enhanced-Definition television, EDTV). The fourth user equipment 124 may for example be a mobile phone. The 480p mode here refers to that it is defined by 480 horizontal lines of vertical image display resolution and progressive scan. The term 480p usually assumes an aspect ratio of 4:3, and may imply a resolution of 620x480 pixels, i.e. about 0.3 megapixels. Also, in this example, the fourth user equipment 124 may be configured to communicate with the network node 1 10 via a radio link of a data network in the communications network 100. Thus, the fourth user equipment 124 may transmit its video quality rendering capability to the network node 110 that may comprise indicators of at least both these aspects.

A fifth user equipment 125 has a medium sized 10 inch screen with a hardware 5 configuration and rendering capabilities that also supports the first high definition video mode or resolution, such as, e.g. 1080p. The fifth user equipment 125 may for example be a tablet computer. Also, in this example, the fifth user equipment 124 may be configured to communicate with the network node 1 10 via a wired communications link of a data network in the communications network 100. Thus, the fifth user equipment 125

10 may transmit its video quality rendering capability to the network node 110 that may

comprise indicators of both these aspects.

This shows that there are multiple factors for each user equipment 121 , 122, 123, 124, 125 that define a range of video quality that may be transmitted to and/or received from each of the connected user equipments 121 , 122, 123, 124, 125 to/from a system

15 maintaining the video communication, i.e. the network node 1 10.

As indicated in the example above, the video quality in real-time services depends to a large extent both on the performance of the data transport network and on the connected devices capabilities.

20 As part of developing the embodiments herein, it has been noticed that a large video quality level variation between video streams may be disturbing to some users. This may occur, for example, when a lower video quality level is selected for some users and a higher video quality level is selected for other users. This is because it may lead to that a device of a user may end up displaying poor resolution video images from some users on

25 a large sized screen which will have a negative impact on the perceived level of video quality experienced by the user of the device, while at the same time displaying high resolution video images from other users on the same large sized screen which will have a positive impact the perceived level of video quality experienced by these user of the device.

30 This is illustrated in Figure 2, which depicts a display 200 of a user equipment, e.g. the first user equipment 121 in Figure 1. The display 200 displays multiple screen windows 210, 220, 230, 240 for different video streams received from different users participating in a video communication service with the user equipment. As illustrated in Figure 2, while the video quality level is high for the data streams shown in the windows

35 220, 230, the video quality level is very low for the data stream shown in the window 210. This large deviation in the perceived level of video quality of simultaneous data streams from different users has been noted to be disturbing to users.

However, it may also be noted that while the data stream shown in window 240 may have a low video quality level, it may also have a limited negative impact on the perceived level of video quality experienced by the user of the user equipment.

Furthermore, in the above case, some devices may also end up in a situation where they receive video streams with a video quality that is very much higher than the devices are able to mediate to its user. For example, a video resolution that is too high to benefit the perceived level of video quality experienced by the user of the device, since the device comprise some limitations, such as, e.g. a small sized screen and/or other video rendering limitations. Thus, for these devices, network bandwidth of the transport network is then used in vain. According to embodiments described herein, these issues are addressed by having the network node that provides the video communication services and limits the range of used video quality in view of all of the connected devices' video rendering capabilities to achieve an experience of a more stable video quality, which also does not overuse the bandwidth of the transport network. This is indicated in Figure 1 by the range of video quality to be used transmitted by the network node 1 10 to the user equipments 121 , 122, 123, 124, 125.

As may be seen in the more detail by the description of the embodiments below with reference to Figures 3-5, the network node 1 10 limits the video quality range such that the highest video quality level provided by the network node is limited to a level that is enough for good quality user experience on devices with small screens and satisfactory good quality user experience on other devices with larger screens. The network node 1 10 also limits the video quality range such that the lowest video quality level provided by the network node is limited to a level that provides a satisfactory good quality experience on all devices. Thus, this smaller defined range of the video quality will result in a video communication service that achieves a good user quality experience with a more stable video quality that does not overuse the transport network bandwidth.

In other words, the video quality range limitation of the embodiments herein makes the quality experience of the video communication service more stable and stationary, while providing a more optimal usage of the transport network. In the example of Figure 1 , the highest video mode or resolution that is sent to the network node 1 10 is 720p (1280x720) at 25Hz frame rate, and the lowest video mode or resolution is 360p (640x360) at 25Hz frame rate. Here, the network node 110 may, according to some of the embodiments described below with reference to Figure 3, determine 480p25 to be sent as the highest video mode or resolution of the video quality range in the video communication, and 360p25 as the lowest video mode or resolution of the video quality range in the video communication. In some embodiments described below, the lowest video mode or resolution, i.e. 360p25, may be used when a lower bandwidth must be used due to transport network constraints.

Example of embodiments of a method performed by a network node 1 10 for enabling a video communication service between two or more user equipments 121-125 in a communications network 100, will now be described with reference to a flowchart depicted in Figure 3. According to some embodiments, the network node 1 10 may be a gateway node for a video communication system in the communications network 100.

Figure 2 is an illustrated example of exemplary actions or operations which may be taken by the network node 1 10. The method may comprise the following actions. Action 301

In this action, the network node 110 receives an indication of the user equipments' video quality rendering capability from each of the two or more user equipments 121-125. In some embodiments, the network node 1 10 may receive the video quality rendering capabilities from the user equipments 121-125 using a Session Description Protocol, SDP (IETF RFC 4566). SDP is normally only used by user equipments to transmit maximum transmission/reception bitrates and supported video resolutions.

Action 302

In this optional action, the network node 110 may receive an indication of a communication service constraint of a network connection within the communications network 100 for at least one of the two or more user equipments 121-125.

In some embodiments, for example, network connection constraints on the communication, such as, e.g. available network bandwidth for a connection to a user equipment, network bandwidth supported by connected user equipments, and possible transport network statistics, etc., may be collected by the network node 1 10 during previous sessions by user equipments. These received bandwidth capabilities and transport network statistics, such as, e.g. packet loss, jitter, bandwidth variation, etc., may be used by the network node 1 10 together with the received video quality rendering capabilities to determine certain video quality aspects, such as, e.g. resolution, frame rate, etc. As seen below, these are important parameters when determining the video quality range.

Action 303

After receiving the video quality rendering capabilities, the network node 110 determines a video quality range of the video communication service between the two or more user equipments. The network node 110 determines the highest video quality of the range based on a highest video quality of the user equipment with the lowest video quality rendering capability. The network node 1 10 also determines the lowest video quality of the range based on a lowest video quality of the user equipment with the highest video quality rendering capability.

This advantageously limits the video quality range used by the network node 110 maintaining the video communication services by limiting the highest and lowest levels of the video quality that will be sent by the network node 1 10 to the two or more user equipments 121-125 to trade-off video quality levels. The video quality range limitation makes the quality experience of the communication service more stable and stationary and the usage of the transport network more optimal.

This is because large video quality variations between data streams during a video communication session in a video communication service, i.e. data streams with very different video quality from different conference participants, which may have been perceived as disturbing to a user is now removed. That is, devices may no longer end up displaying poor resolution video images negatively impacting on the perceived level of video quality, while at the same time displaying high resolution video images positively impacting on the perceived level of video quality. Thus, this contrasting video quality perception by a user has been removed.

Furthermore, some users who might have ended up in situations where they receive video streams with quality properties higher than their device can mediate, e.g. too high video resolution for the device to utilize, and/or the user can perceive on the device due to human visual system limitations, are now ensured to receive video streams that their devices are able to mediate and/or visualize. The trade-off video quality levels may be configured in the network node 1 10 using human visual perception knowledge criteria, play-out criteria of the two or more user equipments, and transport network capabilities criteria for the communication links of the two or more user equipments. These criteria may be configured in order to achieve a 5 particular determined perceived level of video quality experienced by the users of the two or more user equipments.

For example, the criteria may be defined using a database comprising relations between video processing/compression, rendering hardware (such as, e.g. needed processing power, screen size, screen resolution, etc.) and rendering aspects (e.g. frame 10 rate, colour space, use of full screen or not, etc.), and related to them determined video quality levels. The determined video quality levels may be set or determined according to e.g. video quality research which may involve subjective testing. Each criterion may also be regarded as multidimensional video quality vector pointing out a certain video quality level.

15 Thus, the network node 1 10 may use these video quality configurations to limit the highest and lowest levels of video quality, e.g. in terms of video resolution, frame rate, etc., that will be maintained by the video communication services by determining the trade-off levels that may be mediated by all connected devices, i.e. the two or more user equipments, without any need to adapt the received video quality and taking into account

20 connected devices' video quality rendering capabilities, such as, e.g. processing power, screen resolution, colour space, screen sizes, etc.

Figure 4 shows a schematic diagram illustrating an example scenario for embodiments of the network node 1 10 in the communications network 100.

25 The y-axis shows different video quality rendering capabilities of the user

equipments, or more specifically, in this case, the video mode or resolution of the user equipments. The x-axis exemplifies three different user equipments, i.e. UE 121-123.

In this example, for UE 121 , it may be seen that a lowest level of video quality to ensure a determined perceived level of video quality experienced by the user of the UE

30 121 is determined by the network node 1 10, based on the video quality rendering

capabilities of the UE 121 , to be 360p. The network node 110 may also determine that the perceived level of video quality experienced by the user of the UE 121 will increase up to a highest level of video quality; in this case, 1080p. Above this level, no further improvement in the perceived level of video quality will be experienced by the user of the UE 121 , but will only continue to increase the occupied network bandwidth of the transport network.

For UE 122, it may be seen that a lowest level of video quality to ensure a determined perceived level of video quality experienced by the user of the UE 121 is determined by the network node 110, based on the video quality rendering capabilities of the UE 122, to be 160p. The network node 110 may also determine that the perceived level of video quality experienced by the user of the UE 121 will increase up to a highest level of video quality; in this case, 480p. Above this level, no further improvement in the perceived level of video quality will be experienced by the user of the UE 122, but will only continue to increase the occupied network bandwidth of the transport network.

For UE 123, it may be seen that a lowest level of video quality to ensure a determined perceived level of video quality experienced by the user of the UE 123 is determined by the network node 110, based on the video quality rendering capabilities of the UE 123, to be 240p. The network node 110 may also determine that the perceived level of video quality experienced by the user of the UE 123 will increase up to a highest level of video quality; in this case, 720p. Above this level, no further improvement in the perceived level of video quality will be experienced by the user of the UE 123, but will only continue to increase the occupied network bandwidth of the transport network. In some embodiments, the highest video quality of the range may be determined based on the highest video quality of the user equipment with the lowest video quality rendering capability such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) with the highest video quality rendering capability is still achieved. For example, 480p25 may be the highest video quality that the UE 124 in Figure 1 is able to render in order to achieve an improved perceived level of video quality experienced by the user on the UE 121 in Figure 1. In other words, the highest trade-off video quality level should not be higher than that which may be perceived by a user on a device with limited play out capabilities as regards e.g. video resolution, screen size, frame rate, colour space, etc.

In some embodiments, the lowest video quality of the range is determined based on the lowest video quality of the user equipment with the highest video quality rendering capability such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) with the highest video quality rendering capability is achieved. For example, 360p25 may be the lowest video quality for achieving a determined perceived level of video quality experienced by the user on the UE 121 in Figure 1. In other words, the lowest trade-off video quality level is determined by the network node 110 taking into account that it should result in a satisfactory good level of user experience on devices with high quality hardware configuration as regards e.g. processing power, screens sizes and resolution, etc.

In some embodiments, the network node 110 may determine the video quality range of the video communication service between the two or more user equipments 121- 125 further based on the received indication of a video communication service constraint of a network connection within the communications network 100 for the at least one of the two or more user equipments 121-125. This advantageously allows the network node 1 10 to take into account a transport network constraint of a radio or communication link in the communication network 100 when determining the video quality range.

Action 304

In this optional action, the network node 110 may determine a video quality of the video communication service between the two or more user equipments 121-125 within the determined video quality range based on the indication of a video communication service constraint of a network connection within the communications network 100 for the at least one of the two or more user equipments 121-125 as received in Action 202.

This advantageously allows the network node 110 to determine the lowest video mode or resolution, i.e. 360p25 in the example of Figure 1 , to be used when a lower bandwidth must be used due to a transport network constraint of a radio or

communication link in the communication network 100.

Action 305

When the video quality range has been determined, the network node 1 10 enables the video communication service for two or more user equipments 121-125 based on the determined video quality range. In some embodiments, in case the network node 110 is one of several entities in a video communication system, this may be perform by transmitting the determined video quality range to the entity that is to provide the video communication service between the two or more user equipments 121-125. In some embodiments, in case the network node 110 is a single video communication system entity, the network node 1 10 may enable the video communication service between the two or more user equipments 121-125 based on the determined video quality range or determined video quality therein by providing the video communication service between the two or more user equipments 121-125. The provision of the video communication service may here comprise mixing of the video communication data streams from the two or more user equipments 121-125 into a single video communication data stream that may be sent out to the two or more user equipments 121-125.

To perform the method actions in the network node 110 for enabling a video communication service between two or more user equipments 121-125 in a

communications network 100, the network node 110 may comprise the following arrangement depicted in Figure 4.

Figure 5 shows a schematic block diagram of embodiments of the network node 110. In some embodiments, the network node 110 is a gateway node in the

communications network 100.

The network node 110 is configured to, or comprises a transceiving module 511 that is configured to, receive an indication of the video quality rendering capability of the user equipment from each of the two or more user equipments. The network node 110 is also configured to, or comprises a determining module 512 that is configured to, determine a video quality range of the video communication service between the two or more user equipments, wherein the highest video quality of the range is determined based on a highest video quality of the user equipment with the lowest video quality rendering capability and the lowest video quality of the range is determined based on a lowest video quality of the user equipment with the highest video quality rendering capability. The network node 110 is further configured to, or the transceiving module 411 being further configured to, enable the video communication service for two or more user equipments based on the determined video quality range.

In some embodiments, the network node 1 10 is further configured to, or the determining module 412 being further configured to, determine the highest video quality of the range by the lowest video quality rendering capability of the user equipments such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) with the highest video quality rendering capability is still achieved. In some embodiments, the network node 110 is further configured to, or the determining module 412 being further configured to, determine the lowest video quality of the range by the highest video quality rendering capability of the user equipments such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) with the highest video quality rendering capability is achieved.

In some embodiments, the network node 1 10 is further configured to, or the transceiving module 41 1 being further configured to, receive an indication of a

communication service constraint of network connections within the communications network for at least one of the two or more user equipments. In this case, the network node 1 10 may be further configured to, or the determining module 412 may be further configured to, determine a video quality of the video communication service between the two or more user equipments 121-125 within the determined video quality range based on the indication of a video communication service constraints of a network connection within the communications network for the at least one of the two or more user equipments 121- 125. Alternatively, the network node 110 may be further configured to, or the determining module 412 may be further configured to, determine the video quality range based on the indication of a video communication service constraints of a network connection within the communications network for the at least one of the two or more user equipments 121-125.

In some embodiments, the network node 1 10 is further configured to, or the transceiving module 411 being further configured to, provide the video communication service between the two or more user equipments 121-125 based on the determined video quality range.

In some embodiments, the network node 1 10 may comprise a processing circuitry 510, which may also be referred to as processing module or unit. The processing circuitry 510 may comprise one or more of the transceiving module 511 and the determining module 512 described above.

The embodiments for enabling a video communication service between two or more user equipments 121-125 in a communications network 100 may be implemented through one or more processors, such as, e.g. the processing circuitry 510 in the network node 110 depicted in Figure 5, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code or code means for performing the embodiments herein when being loaded into the processing circuitry 510 in the network node 110. The computer program code may e.g. be provided as pure program code in the network node 110 or on a server and downloaded to the network node 110.

The network node 110 may further comprise a memory 520 comprising one or more memory modules or units. The memory 520 may be arranged to be used to store data, such as, e.g. configuration information for the trade-off video quality levels, etc., to perform the methods described herein when being executed in the network node 110. Those skilled in the art will also appreciate that the processing circuitry 510 and the memory 520 described above may refer to a combination of analog and digital circuits, and/or one or more processors configured with software and/or firmware, e.g. stored in a memory, that when executed by the one or more processors such as the processing circuitry 510 perform as described above. One or more of these processors, as well as the other digital hardware, may be included in a single application-specific integrated circuit (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a system- on-a-chip (SoC).

Thus, a computer program, comprising instructions which, when executed on at least one processor, e.g. the processing circuitry or module 510, cause the at least one processor to carry out the method for enabling a video communication service between two or more user equipments 121-125 in a communications network 100 as described above is presented. Also, a carrier containing the computer program, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium, is presented.

The terminology used in the detailed description of the particular exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting of the described method and network node 110 which instead should be construed in view of the enclosed claims.

As used herein, the term "and/or" comprises any and all combinations of one or more of the associated listed items.

Further, as used herein, the common abbreviation "e.g.", which derives from the

Latin phrase "exempli gratia," may be used to introduce or specify a general example or examples of a previously mentioned item, and is not intended to be limiting of such item. If used herein, the common abbreviation "i.e.", which derives from the Latin phrase "id est," may be used to specify a particular item from a more general recitation. The common abbreviation "etc.", which derives from the Latin expression "et cetera" meaning "and other things" or "and so on" may have been used herein to indicate that further features, similar to the ones that have just been enumerated, exist.

As used herein, the singular forms "a", "an" and "the" are intended to comprise also the plural forms as well, unless expressly stated otherwise. It will be further understood that the terms "includes," "comprises," "including" and/or "comprising," when used in this specification, specify the presence of stated features, actions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, actions, integers, steps, operations, elements, components, and/or groups thereof.

Unless otherwise defined, all terms comprising technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the described embodiments belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The embodiments herein are not limited to the above described preferred embodiments. Various alternatives, modifications and equivalents may be used.

Therefore, the above embodiments should not be construed as limiting.

Claims

A method performed by a network node (1 10) for enabling a video communication service between two or more user equipments (121-125) in a communications network (100), the method comprising

receiving (301) an indication of the video quality rendering capability of the user equipment from each of the two or more user equipments (121-125);

determining (303) a video quality range of the video communication service between the two or more user equipments (121-125), wherein the highest video quality of the range is determined based on a highest video quality of the user equipment with the lowest video quality rendering capability and the lowest video quality of the range is determined based on a lowest video quality of the user equipment with the highest video quality rendering capability; and

enabling (305) the video communication service for two or more user equipments (121-125) based on the determined video quality range.

The method according to claim 1 , wherein the highest video quality of the range is determined by the lowest video quality rendering capability of the user equipments (121-125) such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) (121 , 123, 125) with the highest video quality rendering capability is still achieved.

The method according to claim 1 or 2, wherein the lowest video quality of the range is determined by the highest video quality rendering capability of the user equipments (121-125) such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) (121-125) with the highest video quality rendering capability is achieved.

The method according to any of claims 1-3, further comprising

receiving (302) an indication of a communication service constraint of a network connection within the communications network (100) for at least one of the two or more user equipments (121-125). The method according to claim 4, further comprising

determining (304) a video quality of the video communication service between the two or more user equipments (121-125) within the determined video quality range based on the indication of a video communication service constraint of a network connection within the communications network (100) for the at least one of the two or more user equipments (121-125).

The method according to claim 4, wherein the determining (303) further comprises determining the video quality range of the video communication service between the two or more user equipments (121-125) based on the indication of a video communication service constraint of a network connection within the communications network (100) for the at least one of the two or more user equipments (121-125).

The method according to any of claims 1-6, wherein the enabling (305) further comprises providing the video communication service between the two or more user equipments (121-125) based on the determined video quality range or determined video quality.

A network node (1 10) for enabling a video communication service between two or more user equipments (121-125) in a communications network (100), the network node (1 10) being configured to

receive an indication of the quality rendering capability of the user equipment from each of the two or more user equipments (121-125),

determine a video quality range of the video communication service between the two or more user equipments (121-125), wherein the highest video quality of the range is determined by the highest video quality of the user equipment with the lowest video quality rendering capability and the lowest video quality of the range is determined by the lowest video quality of the user equipment with the highest video quality rendering capability, and

enable the video communication service for two or more user equipments (121-125) based on the determined video quality range.

The network node (1 10) according to claim 8, further configured to determine the highest video quality of the range by the lowest video quality rendering capability of the user equipments (121-125) such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) (121 , 123, 125) with the highest video quality rendering capability is still achieved.

10. The network node (1 10) according to claim 8 or 9, further configured to determine the lowest video quality of the range by the highest video quality rendering capability of the user equipments (121-125) such that a determined perceived level of video quality experienced by the user(s) of the video communication service on the user equipment(s) (121 , 123, 125) with the highest video quality rendering capability is achieved.

1 1. The network node (1 10) according to any of claims 8-10, further configured to receive an indication of a communication service constraint of network

connections within the communications network (100) for at least one of the two or more user equipments (121-125).

12. The network node (1 10) according to claim 11 , further configured to determine a video quality of the video communication service between the two or more user equipments (121-125) within the determined video quality range based on the indication of a video communication service constraints of a network connection within the communications network (100) for the at least one of the two or more user equipments (121-125). 13. The network node (1 10) according to claim 11 , further configured to determine a video quality of the video communication service between the two or more user equipments (121-125) within the determined video quality range based on the indication of a video communication service constraints of a network connection within the communications network (100) for the at least one of the two or more user equipments (121-125).

14. The network node (1 10) according to any of claims 8-13, further configured to provide the video communication service between the two or more user equipments (121-125) based on the determined video quality range or determined video quality.

15. The network node (1 10) according to any of claims 8-14, wherein the network node is a gateway node (110) in the communications network (100).

16. Computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 1 to 7.

17. A carrier comprising the computer program according to claim 16, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.