WO2015161512A1

WO2015161512A1 - Methods and devices for video communication in a door entry system, and a door entry system

Info

Publication number: WO2015161512A1
Application number: PCT/CN2014/076253
Authority: WO
Inventors: Wei Fu; Wei HOU; Renfeng ZHOU
Original assignee: Abb Technology Ltd
Priority date: 2014-04-25
Filing date: 2014-04-25
Publication date: 2015-10-29
Also published as: CN106332557A

Abstract

Embodiments of the present disclosure relate to a method and device for transmitting video in a door entry system, a method and device for receiving video in a door entry system, a method and device for coordinating video communication in a door entry system and a door entry system. In an embodiment of the present disclosure,the method for transmitting video in a door entry system comprises sending information on a plurality of video formats supported by a calling device; receiving information on a video format selected from the plurality of video formats by a called device; and sending video in the selected video format. With embodiments of the present disclosure, it can enable video transmission in multiple video formats so that each communication terminal can receive video in a video format suitable for itself, which can well process issues on performance difference among different communication terminals in the door entry system and will greatly improve the user experience.

Description

METHODS AND DEVICES FOR VIDEO COMMUNICATION IN A DOOR ENTRY SYSTEM, AND A DOOR ENTRY SYSTEM FIELD OF THE INVENTION

[0001] Embodiments of the present disclosure generally relate to a door entry system, and more particularly relate to a method and device for transmitting video in a door entry system, a method and device for receiving video in a door entry system and a door entry system.

BACKGROUND OF THE INVENTION

[0002] Nowadays, door entry systems (DES) are very popular especially in residence buildings. The DES is arranged to provide a security protection centrally, safely and efficiently. In most of existing door entry system, the incoming video is transmitted in a standard definition (SD) format, which has a lower requirement on the performance of the terminals and has an advantage of low price. However, since the

SD format has a low definition, it brings a slight bad user experience.

[0003] On the other hand, with the development of technology, the cost of terminals with high performance is constantly decreased and it is becoming a trend to use a high definition (HD) format in DES. Thus, there might be more and more high performance terminals (such as smart phone, tablet or the like) used in the DES and these high performance terminals might coexist with existing low performance terminals for a long time.

[0004] In such a case, it is a challenge to enable communication terminals with different performance to obtain their respective best video performance in a door entry system.

SUMMARY OF THE INVENTION

[0005] To this end, the present disclosure provides a new solution for video communication in a door entry system so as to solve or at least partially mitigate at least a part of problems in the prior art.

[0006] According to a first aspect of the present disclosure, there is provided a method for transmitting video in a door entry system. The method comprises sending information on a plurality of video formats supported by a calling device; receiving information on a video format selected from the plurality of video formats by a called device; and encoding and sending video in the selected video format.

[0007] In an embodiment of the present disclosure, the information on a plurality of video formats supported by a calling device may be contained in a call request. Alternatively or additionally, the information on a video format selected from the plurality of video formats by a called device may be contained in a call response.

[0008] In another embodiment of the present disclosure, the method may further comprise deleting a video encoder and a video sending unit for a video format which is not to be kept in response to an off hook request, wherein the off hook request contains information on a video format to be kept.

[0009] According to a second aspect of the present disclosure, there is provided a method for receiving video in a door entry system. The method may comprise receiving information on a plurality of video formats supported by a calling device; selecting a video format from the plurality of video formats; sending information on the selected video format; and receiving and decoding video in the selected video format.

[0010] According to a third aspect of the present disclosure, there is further provided method for coordinating video communication in a door entry system. The method may comprise forwarding information on a plurality of video formats supported by a calling device to a called device; creating, in response to receipt of information on a video format selected from the plurality of video formats by the called device, a channel for the selected video format; forwarding the information on the selected video format to the calling device; and forwarding video in the selected video format from the calling device to the called device through the channel created for the selected video format.

[0011] According to a fourth aspect of the present disclosure, there is further provided a device for transmitting video in a door entry system. The device comprises: a sending unit configured to send information on a plurality of video formats supported by a calling device; a receiving unit configured to receive information on a video format selected from the plurality of video formats by a called device; a video encoding and sending unit configured to send video in the selected video format.

[0012] According to a fifth aspect of the present disclosure, there is provided a device for receiving video in a door entry system. The device comprises a receiving unit configured to receive information on a plurality of video formats supported by a calling device; a call maintenance unit configured to select a video format from the plurality of video formats; a sending unit configured to send information on the selected video format; and a video receiving and decoding unit configured to receive and decode video in the selected video format.

[0013] According to a sixth aspect of the present disclosure, there is provided a device for coordinating video communication in a door entry system. The device comprises a proxy unit configured to forward information on a plurality of video formats supported by a calling device to a called device and forward information on a video format selected from the plurality of video formats by the called device to the calling device; a channel management unit configured to create, in response to receipt of the information on the selected video format from the called device, a channel for the selected video format; and a video forwarding unit configured to forward video in the selected video format to the called device through the channel created for the selected video format.

[0014] According to a seventh aspect of the present disclosure, there is further provided, a computer-readable storage media with computer program code embodied thereon, the computer program code configured to, when executed, cause an apparatus to perform actions in the method according to an embodiment in any one of the first to third aspects of the present disclosure.

[0015] According to an eighth aspect of the present disclosure, there is provided a computer program product comprising a computer-readable storage media according to the seventh aspect of the present disclosure.

[0016] In embodiments of the present disclosure, auto-negotiation about the video format can be made between a calling device and a called device, and thus the calling device can transmit video to the called device based on the negotiation results. Therefore, with embodiments of the present disclosure, it can enable video transmission in multiple video formats so that each communication terminal can receive video in a video format suitable for itself, which can well process issues on performance difference among different communication terminals in a door entry system and will greatly improve user experience.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features of the present disclosure will become more apparent through detailed explanation on the embodiments as illustrated in the description with reference to the accompanying drawings, throughout which like reference numbers represent same or similar components and wherein:

[0018] Fig. 1 schematically illustrates a flow chart of a method for transmitting video in a door entry system according to an embodiment of the present disclosure;

[0019] Fig. 2 schematically illustrates a flow chart of a method for receiving video in a door entry system according to another embodiment of the present disclosure;

[0020] Fig. 3 schematically illustrates a flow chart of a method for coordinating video communication in a door entry system according to a further embodiment of the present disclosure;

[0021] Fig. 4 schematically illustrates a diagram of an door entry system in one-to-one mode;

[0022] Fig. 5 schematically illustrates a signaling diagram of a specific implementation of auto-negotiation on video format selection in the one-to-one mode according to an embodiment of the present disclosure;

[0023] Fig. 6 schematically illustrates a diagram of a door entry system in one-to-multiple mode;

[0024] Fig. 7 schematically illustrates a signaling diagram of a specific implementation of auto-negotiation on video format selection in one-to-multiple mode according to another embodiment of the present disclosure;

[0025] Fig. 8 schematically illustrates a block diagram of a device for transmitting video in a door entry system according to an embodiment of the present disclosure;

[0026] Fig. 9 schematically illustrates a block diagram of a device for receiving video in a door entry system according to another embodiment of the present disclosure;

[0027] Fig. 10 schematically illustrates a block diagram of a device for coordinating video communication in a door entry system according to a further embodiment of the present disclosure; and

[0028] Fig. 11 schematically illustrates a block diagram of a door entry system according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

[0029] Hereinafter, solutions as provided the present disclosure will be described in details through embodiments with reference to the accompanying drawings. It should be appreciated that these embodiments are presented only to enable those skilled in the art to better understand and implement the present disclosure, not intended to limit the scope of the present disclosure in any manner.

[0030] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a/an/the/said [element, device, component, means, step, etc]" are to be interpreted openly as referring to at least one instance of said element, device, component, means, unit, step, etc., without excluding a plurality of such devices, components, means, units, steps, etc., unless explicitly stated otherwise. Besides, the indefinite article "a/an" as used herein does not exclude a plurality of such steps, units, modules, devices, and objects, and etc.

[0031] Next, reference will be first made to Fig. 1 to describe the method for transmitting video in a door entry system according to an embodiment of the present disclosure, which is performed at the calling device. As illustrated in Fig. 1, first at step S101, information on a plurality of video formats supported by a calling device may be sent to a called device. In embodiments of the present disclosure, the calling device may support a plurality of video formats to meet different requirements on video formats from diversified terminals. The term "video format" used herein refers to video encoding format, resolution, frame rate, bit rate and so on. The information on the plurality of video formats supported by the calling device may be stored in the calling device, and it may be a list of video formats or other thing like that. The information on these video formats may be sent by the calling device to the called device. The information on supported video formats can be sent as a single message but it is preferable to contain the information on supported video formats in a call request. In other words, when the calling device makes a call, the information on supported video formats can be included in the call request and sent to the called device together with the call request. The call request is a message which will be sent to the called device when a user makes a call to inform the called device of an incoming call. It is beneficial to contain the information on the supported video formats in the call request because it did not require adding any further signaling in the door entry system, and it may provide a better compatibility.

[0032] At step S102, information on a video format selected from the plurality of video formats by a called device is received at the calling device. After the called device receives the information on the plurality of video formats supported by the calling device, it will select a video format from the plurality of video formats according to its own performance, for example, it may select from the plurality of video formats the best video format that it can support as its video format for the incoming video. The information about the selected video format will be sent back to the calling device. This information can be sent to the calling device as a separate message or it can be included in a call response and be sent to the calling device together with a call response. The call response will be sent to the calling device by the called device once after the called device receives the call request from the calling device, so as to tell the called device that it is ready for an incoming call. Similarly, it is also beneficial to contain the information on the selected video format in the call response because of better compatibility.

[0033] After receiving the information on the selected video format, the calling device will encode the video according to the selected video format and send the video in the selected video format to the called device at step S I 03.

[0034] In a case of more than one called devices, the information on the plurality of video formats will be sent to these called devices; and for each of selected video formats, there will be a corresponding encoder and sending unit so that videos in these selected video formats may be sent to respective called devices. Besides, in such a case, when the calling device receives an off hook request containing a video format to be kept, the calling device will delete a video coding and sending unit for video format not to be kept (video format not contained in the off hook request ). In such a way, the resource allocated to the video format not be kept may be released when it is not to be used.

[0035] In addition, Fig. 2 illustrates a flow chart of a method for receiving video in a door entry system according to another embodiment of the present disclosure, which is performed at the called device. Next, reference will be made to Fig. 2 to describe operations at the called device.

[0036] As illustrated in Fig. 2, first at step S201, the called device will receive the information on a plurality of video formats supported by a calling device. The information for example includes a list of video formats which can be supported by the calling device. As mentioned before, the information on the supported video formats for example may be contained in a call request from the calling device and sent to the called device together with in the call request, which will be beneficial because of better compatibility.

[0037] Then, at step S202, the called device may select, based on its own performance, a video format from the plurality of video formats, as the video format for the incoming video. For example, it may select from the plurality of video formats the best video format that it can support as its video format for the incoming video. Next, at step S203, information on the selected video format will be provided to the calling device to inform of the video format for the incoming video. As already mentioned hereinabove, the information on the selected video format may be for example contained in a call response to the calling device and sent thereto together with the call response, which could provide better compatibility. Afterwards, the called device can receive video in the selected video formation at step S204. Accordingly, the called device can decode the video in the selected video format and display the video on screen of the called device.

[0038] Besides, in case of more than one communication terminals, if a user desires off hook, i.e., answer the call with the called device desires, it may send an off hook request containing the video format of its own video format which is to be kept in subsequent communication. In other word, the call will be answered by this called device while other called device will terminate the call. Thus, when the calling device receives the off hook request, the calling device will delete a video encoder and a video sending unit for video formats other than that is contained in the off hook request so as to release unused resource. [0039] In addition, in case of more than one communication terminals, there can be an intermediate device like a server to coordinate the video communication between the calling device and these called devices. Next description on operations of the server may be made with reference to Fig. 3 which schematically illustrates a flow chart of a method for coordinating video communication in a door entry system according to a further embodiment of the present disclosure.

[0040] As illustrated in Fig. 3, first at Step S301, the server will forward information on a plurality of video formats supported by a calling device to a called device. In embodiments of the present disclosure, all information or communication from the calling device will be first sent to the server which will in turn forward them to respective communication terminals. Therefore, when the server receives the information on the supported video formats from the calling device, it will forward it to all called devices. Besides, the information on the supported video formats may be contained in a call request and sent to the server together with the call request as a part of information of the call request so as to obtain better compatibility.

[0041] Then at step S302, when the server receives information on a video format selected form the plurality of video formats by a called device, it will create a channel for this selected video format. The created channel will be used to forward video in the selected video format. If there is a plurality of different selected video formats, the server will create channels for these video formats respectively. However, if there is already a channel for the selected video format or in other word, other communication terminal already selects the same video format as this called device, then they can share the same channel. That is to say, it is usually enough to use one channel to forward video in the selected video to these devices with the same selected video format.

[0042] Then at step S303, the server will forward the information on the selected video format to the calling device so as to inform the calling device of the selection made by the called device. Similarly, the information on the selected video format may be information contained in the call response and sent to the calling device. After that, when the server receives the video in the selected video format from the calling device, it may forward the video to destination called device (i.e., a called device which selects the video format as its video format for the incoming video) on the channel created for the selected video format at step S304.

[0043] Besides, when the server receives from a called device an off hook request containing the video format to be kept, it will delete all channels for video format not to be kept (i.e., those video formats not contained in the off hook request) and cancel other called device except the called device making the off hook request. That is to say, only the called device making the off hook request and the channel for the selected video format of the called device will be maintained, all other channels will be deleted and all other called device will be cancelled. In such a way, resource allocated for the other called devices may be released in the server.

[0044] In embodiments of the present disclosure, auto-negotiation about the video format can be made between a calling device and a called device, and thus the calling device can transmit video to the called device based on the negotiation results. Therefore, with embodiments of the present disclosure, it can enable video transmission in multiple video formats in a single door entry system so that each communication terminal can receive video in a video format suitable for itself, which can well process issues on performance difference among different communication terminals and will greatly improve the user experience.

[0045] Hereinafter, in order to make the skilled in the art to understand the solution as provided in the present disclosure completely and thoroughly, reference will be made to Figs. 4 to 7 to explain specific implementations of auto-negotiation on video format selection according to an embodiment of the present disclosure.

[0046] First reference is made to Fig. 4, which illustrates a scenario of a door entry system in one-to-one mode. As illustrated in Fig. 1, device 410 is a calling device 410 and device 420 is a called device. The device 410 communicates with the device 420 in one to one mode without any other intermediate device. However, it should be noted that it is also possible to have an intermediate device therebetween.

[0047] Fig. 5 schematically illustrates a signaling diagram of a specific implementation of auto-negotiation on video format selection in the one-to-one mode according to an embodiment of the present disclosure. As illustrated in Fig. 5, the device 410 sends a call request to the device 420 at step S501, wherein the call request contains a list of video formats that can be supported by the device 410. Upon receiving the call request, the device 420 will select a best video format based on its own performance at step S502. At the same time, the device 420 invokes receiving module, decoding module, and displaying module for the incoming video data in the selected video format. After that the device 420 contains the information about the selected best video format in the call response and sends it back to the device 410 at step S503. At the device 410, it will invoke corresponding encoder and sender for video in the selected video format, the video data will be sent to the encoder to be encoded by the encoder and then be sent by the sender to the device 420 at step S504. At the device 420, the video will be received by the video receiving module, decoded and displayed by the corresponding modules.

[0048] It may be seen that in a case of a door entry system in one-to-one module, operations are simpler while operations are much more complex in a door entry system in one-to-multiple module, which will be described hereinbelow.

[0049] Fig. 6 schematically illustrates a diagram of a door entry system in one-to-multiple mode. As illustrated in Fig. 6, for example in apartment 610, there is provided a server 620, which can also be called as household server. The server 620 is connected to a device 610 which may be an outdoor station for using by a user to make a call. On the other hand, the server 620 is connected to a router 640. Communication terminals 650-1 and 650-2 like indoor station or mobile terminal are connected to the router 140. In such a way, communication terminals 650-1, 650-2 can communicate with the server 620 via the router 640. However, it should be noted that it is also possible to connect one or both of communication terminals 650-1, 650-2 to the router 640 wirelessly, for example through WiFi, or other wireless communication technology. In the scenario as illustrated, the calling device 630 will communicate with more than one called devices 650-1 and 650-2, and thus the scenario may be called as one-to-multiple mode.

[0050] Next, detailed description will be made to a specific implementation of auto-negotiation on video format selection in the one-to-multiple mode with reference to Fig. 7. As illustrated in Fig. 7, when the calling device 630 such as outdoor station makes a call, the call request is sent to the server 620 at step S701 and in the call request is contained a list of video formats that can be supported by the calling device 630. After that, at step S702, the server 620 forwards the call request to both communication terminals 650-1 and 650-2 at steps S702a and 702b respectively. Upon receipt of the call request, the communication terminal 650-1 selects a best video format VF_1 from the list of video formats and invokes receiving module, decoding module and display module for the selected best video format so as to be used when the video in the selected video format VF_1 is received at step S703a. At the same time, at step S703b, the communication terminal 650-2 performs similar operations but selects a different video format VF_2. Then at steps S704a and S704b, call responses containing respective selected video formats are sent back to the server 620. Due to two different types of video formats, at step 705a and 705b, the server 620 will create corresponding video channels for two selected video formats, after receiving the corresponding call responses from communication terminals 650-1 and 650-2. After a video channel is created, the server 620 forwards the corresponding call responses to the device 630 at step S706a and S706b respectively. When the calling device 630 receives the call response from the called device 650-1, it will invoke corresponding encoder and sender to encode the video data and send the video data to the server 620 and the same operations is done for the call response from the called device 650-2. In such a way, video in VF_1 and video in VF_2 are sent to the server and at the server 620, the video in VF_1 will be forwarded to called device 650-1 through the video channel created for VF_1 at step S708a while the video in VF_2 will be forwarded to called device 650-1 through the video channel created for VF_2 at step S708b.

[0051] When a called device for example 650-1 decides off hook (i.e., answering the call), it may send to the server an off hook request containing its own video format VF_1, which indicates a video format that should be kept in subsequent communication (step S709). When the server receives from the called device 650-1 the off hook request containing the video format to be kept, it will delete all channels for video format not to be kept (i.e., channel for VF_2, those video formats not contained in the off hook request) and cancel other called device except the called device making the off hook request, if any (step S710). That is to say, only the called device 650- 1 making the off hook request and the channel for the selected video format VF_1 of the called device will be maintained, all other channel VF_2 will be deleted and all other called device will be cancelled. In such a way, resource allocated for the other called devices may be released in the server. Then at step S711, the server will send a cancel request to the other called device 650-2 except the called device 650-1 that makes the off hook request (step S711). After the called device 650-2 receives the cancel request, he will delete decoder and receiver for its selected video format and back to idle state. Then, send a cancel response to the server at step S712. After receiving all cancel response from other cancelled terminals, the server 620 will forward the off hook request contained the video format VF_1 which is to be kept to the calling device 630 at step S713. At step S714, the calling device 630 will delete video encoder and sender for VF_2. Next, an off hook response will be sent to the server 620 at step S714, and at step S715, the off hook response will be forwarded by the server 620 to the called device 650-1. Then after that, only video in VF_1 will be sent to the server 620 and forwarded by the server 620 through the channel for VF_1 to the called device 650-1.

[0052] Hereinafter, description will be further made to a device of transmitting video in a door entry system, a device of receiving video in door entry system and a door entry system as provided in the present disclosure with reference to Figs. 8 to 11.

[0053] Fig. 8 schematically illustrates a block diagram of a device for transmitting video in a door entry system according to an embodiment of the present disclosure. As illustrated in Fig. 8, device 800, which is a calling device, comprises a sending unit 810, a receiving unit 820 and a video encoding and sending unit 830. The sending unit 810 is configured to send information, messages or signaling such as a call request, an operation response and so on from the calling device to a called device, especially to send information on a plurality of video formats supported by the calling device. The receiving unit 820 is configured to receive information, messages or signaling such a call response, an operation request and so on from a called device, and especially to receive the information on the selected video format. The video decoding and sending unit 830 is configured to send video to the called device.

[0054] Particularly, in embodiments of the present disclosure, device 800 (a calling device) such as an outdoor station can support a plurality of video formats. Information on a plurality of video formats supported by the calling device may be sent by the sending unit 810 to a calling device. After a called device selects one video format from the plurality of video formats, information on the selected video formats will be sent to the calling device and the receiving unit 820 may receive the information on the selected video format. After learning the video format selected by the called device, the video data may be encoded by a corresponding encoder in the selected video format and the video sending unit 830 may send video in the selected video format to the called device. In an embodiment of present disclosure, the information on a plurality of video formats supported by a calling device can be contained in a call request. Alternatively or additionally, the information on a video format selected from the plurality of video formats by a called device may be contained in a call response.

[0055] Besides, device 800 may further comprises a call maintenance unit 840, which may be configured to deal things related to calls. For example, the call maintenance unit 830 may obtain the information on the plurality of video formats supported by the calling device and transmit the information to the sending unit so as to be sent to the called device. Besides, the call maintenance unit 840 may invoke an encoder for a selected video format to obtain video data in the selected video format and invoke a corresponding sender to send the video data in the selected video format. In addition, upon receiving an off hook request containing information on a video format to be kept, the call maintenance 840 may be configured to delete a video encoder and a video sending unit for a video format which is not to be kept in response to an off hook request.

[0056] Besides, Fig. 9 schematically illustrates a block diagram of a device for receiving video in a door entry system according to another embodiment of the present disclosure. The device 900 is a called device, which comprises a receiving unit 910, a call maintenance unit 920, a sending unit 930 and a video receiving and decoding unit 940 as illustrated in Fig. 9. The receiving unit 910 is configured to receive information, message, signaling and so on from a calling device, especially, it is configured to receive information on a plurality of video formats supported by a calling device. The call maintenance unit 920 is configured to deal with things related to the call, especially, select a video format from the plurality of video formats as the video format for the incoming video. The sending unit 930 is configured to send information, messages or signaling such as a call response, an operation request and so on to a calling device, especially send information on the selected video format. The video receiving and decoding unit is configured to receive video in the selected video format. In embodiment of the present disclosure, the information on a plurality of video formats supported by a calling device is contained in a call request. Additionally, or alternatively, the information on the selected video format is contained in a call response.

[0057] Beside, in embodiments of the present disclosure, the sending unit 910 is further configured to send an off hook request. Especially, the off hook request contains a video format of its own to inform of the video format to be kept.

[0058] Fig. 10 schematically illustrates a block diagram of a device for coordinating video communication in a door entry system according to a further embodiment of the present disclosure. As illustrated in Fig. 10, device 1000, which may be an intermediate device such a server, comprises a proxy unit 1010, a channel management unit 1020, and a video forwarding unit 1030. The proxy unit 1010 is configured to receive and forward information, messages, signaling and so on between a called device and a calling device, and especially, the proxy unit 1010 is configured to forward information on a plurality of video formats supported by a calling device to a called device and forward information on a video format selected from the plurality of video formats by the called device to the calling device. The channel management unit 1020 is configured to manage channel for forwarding video to the called device, and especially create, in response to receipt of the information on the selected video format from the called device, a channel for the selected video format. The video forwarding unit 1030 is configured to forward video in the selected video format from the calling device to the called device through the channel created for the selected video format. In embodiments of the present disclosure, the information on a plurality of video formats supported by a calling device may be contained in a call request; alternatively or additionally, the information on the selected video format is contained in a call response. Besides, the channel management unit 1030 may be further configured to delete a channel for a video format which is not to be kept in response to an off hook request from a called device and at the same time the proxy unit 1010 may be configured to cancel other called device except the called device making the off hook request, wherein the off hook request contains information on a video format to be kept.

[0059] Fig. 11 schematically illustrates a block diagram of a door entry system according to an embodiment of the present disclosure. The door entry system 1100 comprises an outdoor station 1110, a server 1120, a router 1130, and at least one communication terminal 1140-1, 1140-2. The outdoor station 1110 is to be used by a caller to make a call. The communication terminals 1140-1, 1140-2 such as indoor station or mobile terminal are to be used by a user to answer the call. The server 1120 is configured to coordinate video communication between the outdoor station and the communication terminal. The router 1130 is configured tor enable the communication terminal to communicate with the server 1120.

[0060] Especially, the outdoor station 1110 is configured to send information on a plurality of video formats supported by the outdoor station; receive information on a video format selected from the plurality of video formats by the communication terminal; and encode and send video in the selected video format. The server 1120 is configured to forward the information on the plurality of video formats; create, in response to receipt of information on the video format selected from the plurality of video formats by the communication terminal, a channel for the selected video format; forward the information on the selected video format to the outdoor station; and forward the video in the selected video format from the outdoor station to the communication terminal through the channel created for the selected video format. The communication terminals 1140-1, 1140-2 are configured to receive information on the plurality of video formats; select a video format from the plurality of video formats; send information on the selected video format; and receive and decode video in the selected video format. The information on a plurality of video formats supported by a calling device is contained in a call request; and the information on the selected video format is contained in a call response.

[0061] The devices and the door entry system as provided in embodiments of the present disclosure have been described with reference to the accompanying drawings. However, it may be also appreciated that all these units, modules described herein performs similar operations as described hereinbefore with regarding to the method. Accordingly, for details about these operations, please refer to the description about the method with reference to Figs. 1 to 7.

[0062] Hereinabove, embodiments of the present disclosure have been described in details through embodiments with reference to the accompanying drawings. It should be appreciated that, while this specification contains many specific implementation details, these details should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination.

[0063] Various modifications, adaptations to the foregoing exemplary embodiments of this disclosure may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings. Any and all modifications will still fall within the scope of the non-limiting and exemplary embodiments of this disclosure. Furthermore, other embodiments of the disclosures set forth herein will come to mind to one skilled in the art to which these embodiments of the disclosure pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings.

[0064] Therefore, it is to be understood that the embodiments of the disclosure are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are used herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

WHAT IS CLAIMED IS:

1. A method for transmitting video in a door entry system, comprising:

sending information on a plurality of video formats supported by a calling device; receiving information on a video format selected from the plurality of video formats by a called device; and

encoding and sending video in the selected video format.

2. The method according to Claim 1, wherein the information on a plurality of video formats supported by a calling device is contained in a call request; and/or

wherein the information on a video format selected from the plurality of video formats by a called device is contained in a call response.

3. The method according to Claim 1 to 2, further comprising:

deleting a video encoder and a video sending unit for a video format which is not to be kept in response to an off hook request, wherein the off hook request contains information on a video format to be kept.

4. The method for receiving video in a door entry system, comprising:

receiving information on a plurality of video formats supported by a calling device;

selecting a video format from the plurality of video formats;

sending information on the selected video format; and

receiving and decoding video in the selected video format.

5. The method according to Claim 4, wherein the information on a plurality of video formats supported by a calling device is contained in a call request; and/or

wherein the information on the selected video format is contained in a call response.

6. The method according to Claim 4 or 5, further comprising

sending an off hook request, wherein the off hook request contains a video format to be kept.

7. The method for coordinating video communication in a door entry system, comprising

forwarding information on a plurality of video formats supported by a calling device to a called device;

creating, in response to receipt of information on a video format selected from the plurality of video formats by the called device, a channel for the selected video format; forwarding the information on the selected video format to the calling device; and forwarding video in the selected video format from the calling device to the called device through the channel created for the selected video format.

8. The method according to Claim 7, wherein the information on a plurality of video formats supported by a calling device is contained in a call request; and/or

9. The method according to Claim 7 or 8, further comprising:

deleting a channel for a video format which is not to be kept in response to an off hook request from a called device, wherein the off hook request contains information on a video format to be kept; and

cancelling other called device except the called device making the off hook request.

10. A device for transmitting video in a door entry system, comprising:

a sending unit configured to send information on a plurality of video formats supported by a calling device;

a receiving unit configured to receive information on a video format selected from the plurality of video formats by a called device; and

a video encoding and sending unit configured to send video in the selected video format.

11. The device according to Claim 10, wherein the information on a plurality of video formats supported by a calling device is contained in a call request; and/or

12. The device according to Claim 10 or 11, further comprising:

a call maintenance unit configured to delete a video encoder and a video sending unit for a video format which is not to be kept in response to an off hook request, wherein the off hook request contains information on a video format to be kept.

13. The device for receiving video in a door entry system, comprising:

a receiving unit configured to receive information on a plurality of video formats supported by a calling device;

a call maintenance unit configured to select a video format from the plurality of video formats;

a sending unit configured to send information on the selected video format; and a video receiving and decoding unit configured to receive and decode video in the selected video format.

14. The device according to Claim 13, wherein the information on a plurality of video formats supported by a calling device is contained in a call request; and/or

15. The device according to Claim 13 or 14, wherein, the sending unit is further configured to send an off hook request, wherein the off hook request contains a video format to be kept.

16. The device for coordinating video communication in a door entry system, comprising

a proxy unit configured to forward information on a plurality of video formats supported by a calling device to a called device and forward information on a video format selected from the plurality of video formats by the called device to the calling device;

a channel management unit configured to create, in response to receipt of the information on the selected video format from the called device, a channel for the selected video format; and

a video forwarding unit configured to forward video in the selected video format to the called device through the channel created for the selected video format.

17. The device according to Claim 16, wherein the information on a plurality of video formats supported by a calling device is contained in a call request; and/or

18. The device according to Claim 16 or 17, wherein the channel management unit is configured to delete a channel for a video format which is not to be kept in response to an off hook request from a called device, the off hook request containing information on a video format to be kept; and

wherein the proxy unit is further configured to cancel other called devices except the called device making the off hook request in response of the off hook request.

19. A door entry system, comprising

an outdoor station for using by a caller to make a call;

a communication terminal for using by a user to answer the call;

a server for coordinating video communication between the outdoor station and the communication terminal; and

a router for enabling the communication terminal to communicate with the server, wherein the outdoor station is configured to send information on a plurality of video formats supported by the outdoor station; receive information on a video format selected from the plurality of video formats by the communication terminal; and send video in the selected video format;

the server is configured to forward the information on the plurality of video formats; create, in response to receipt of information on the video format selected from the plurality of video formats by the communication terminal, a channel for the selected video format; forward the information through the selected video format to the outdoor station; and forward the video in the selected video format from the outdoor station to the communication terminal on the channel created for the selected video format; and the communication terminal is configured to receive information on the plurality of video formats; select a video format from the plurality of video formats; send information on the selected video format; and receive video in the selected video format wherein the information on a plurality of video formats supported by a calling device is contained in a call request; and the information on the selected video format is contained in a call response.