Abstract:
A message storage device  114  configured to store users&#39; messages electronically. The message storage device  114  is configured to interact with a user&#39;s electronic device  100,101,104,105,108,110,113  for transmitting a message to and/or receiving a message from the storage device in a manner dependent on the functionality of the user&#39;s electronic device  100,101,104,105,108,110,113.  Also described is a moving image message processor in which an input moving image message stream including at least one first key frame is processed to include second key frames at a predefined time interval apart. Also described is a message storage device  114  including a controller configured to control movement of encoded video messages to and from a store and a processor depending on at least one predefined condition.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. patent application Ser. No. 61/488,203, titled “A MESSAGE STORAGE DEVICE AND A MOVING IMAGE MESSAGE PROCESSOR”, filed on May 20, 2011, the contents of which are incorporated herein by reference. This application is also related to U.S. patent application Ser. No. 61/488,197, titled “A MOVING PICTURE COMMUNICATION SYSTEM” filed on May 20, 2011, the contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to a message storage device and a moving image message processor. 
         [0003]    Described embodiments relate to a method and system for providing a video-enabled enhancement of audio voicemail features to users of videotelephony networks in an enterprise environment, particularly in large enterprises with 5000 or more people. 
         [0004]    Electronic voice communications today are carried out by a great variety and range of devices, such as traditional land-line or fixed-line telephones and mobile phones as well as smartphones. Today, land-line telephones mainly have a dual-tone multi-frequency signalling (DTMF) or Touch-tone keypads including numeral keys 0 to 9 as well as a “*” key and a “#” key together with, in enterprise environments, some extra function keys to, for example, transfer calls, put a caller on hold or access voicemail. Mobile telephones typically also have DTMF keypads, but also some other function keys which vary in number and function from manufacturer to manufacturer and model to model. Some of these function keys may be user definable. Smartphones, on the other hand, typically have a touch-screen which defines keys whose number and function may be varied and defined both by a user, an app or application running on the smartphone or from an external input. A DTMF keypad may be defined as well as other arrangements. 
         [0005]    Recently, real-time video communications (also including voice) have become more wide spread and may be carried out using a great variety of devices including smartphones, typically using proprietary video networks such as Apple Facetime (registered trade mark) or Skype (registered trade mark) (both also useable using a standard desktop or laptop personal computer), as well as fixed-line systems often seen in enterprise environments such as (1) “all-in-one” personal videoconferencing telephones or video-enabled Internet protocol (IP) telephones, such as the Tandberg T150, that look much like a conventional fixed-line phone with the addition of a camera; (2) videoconferencing room systems or Integrated Services Digital Network (ISDN) videoconferencing devices, such as the Tandberg Telepresence T3; and (3) IP videoconferencing endpoints or software plug-ins for general-purpose computers connected to voice-only telephones, such as the Cisco VT Advantage. All of these devices have different functionality and capabilities, including different user interfaces and different screen sizes, resolutions and configurations. 
         [0006]    A “video-voicemail” system is an arrangement in which a caller calling another person&#39;s device (the callee) is provided with a recorded message if the callee is not available typically along the lines of, “This is Bob&#39;s phone. Please leave a message after the tone”. The caller is provided with the ability to record a message for the callee such as “Please call me when you are free”. In a video-voicemail environment, these messages may include video, such as of the caller or callee speaking, as well as audio. 
         [0007]    As a result of the great variation in accessing devices described above, compatibility of enterprise “video-voicemail” systems for video and audio calls has been problematic and a reliable service has not been available. This is one reason why such systems have not become widely accepted. 
         [0008]    Known video/voicemail systems are typically tied to one specific video network such as Apple Facetime (registered trade mark), and are little more than a video equivalent of an answerphone where the caller can leave a message and the callee can retrieve it. Advanced features (for example, folders, group mailboxes, message forwarding, and message multicast and broadcast) found in voice-only enterprise-class voicemail systems are not found in known video/voicemail systems. 
         [0009]    Embodiments of the invention described herein address these problems of lack of cross-video-network compatibility and features to provide a video/voicemail system that may be used with great variation in the functionality of accessing devices or endpoints. 
         [0010]    Video data for video/voicemail systems requires large amounts of electronic data and thus it is compressed both for storage (to reduce the storage space required to manageable levels) and transmission (to reduce bit rates required to manageable levels). 
         [0011]    There are differences in functionality between video endpoints. For example, there may be differences in video compression protocols that they can handle, and differences in permitted image sizes. Embodiments of the invention described herein provide a video/voicemail system to handle these differences effectively and efficiently. 
         [0012]    Another reason why video-voicemail systems have not been widely accepted is usability. In audio-only voicemail systems, audio data is typically stored uncompressed because little electronic data needs to be stored to represent the voicemail and it can be transmitted at a low bitrate. During playback of audio-only voicemail messages, users have become used to precisely being able to fast forward or rewind the message to, for example, listen again to a telephone number that has been said. As voicemail data is typically uncompressed, this is simple to implement. 
         [0013]    In contrast, for video systems, as mentioned above, video data requires relatively large amounts of electronic data and thus it is compressed both for storage and transmission. The compression of the data is generally optimised to minimise bit rate and latency. For example using the H.264 format, greatly simplified, compression is done by sending a starting frame (key frame or intra frame) including a full image and subsequent difference frames which describe how parts of the image have changed since previous frames. In other words, the key frames are decodeable independently of other image frames while subsequent frames are decodeable dependent on other frames. Keyframes require relatively large amounts of storage space and bandwidth or bit rate compared to difference frames. Thus to reduce these requirements, the number of key frames is minimised. In a broadcast video system such as digital TV, key frames are sent at regular short intervals so that, for example, when someone changes to a new channel a TV will only after a short delay receive a key frame and will therefore be able to start displaying video. However, in a videoconferencing network the receiver is able to send messages to the transmitter. This enables the receiver to request that the transmitter send a key frame. Thus, the video network is able to avoid sending key frames at all unless they are actually needed, allowing the bit rate to be kept low. 
         [0014]    A video stream stored in a voicemail system using a file formatted in this way may be readily played from start to finish. However, users require to fast forward and rewind video messages or, in other words, seek to a point in the video stream and the methodology described above of storing and transmitting video data means that this is not possible in a way that provides a good user experience. This is because a required image at a particular point in time is likely to be represented only by a difference frame. Thus, to display the image represented at this point in time the other frames required to decode the difference frame must be sought and themselves decoded. This is a time consuming process and leads to jerky and/or slow “fast” forwarding or rewinding giving a very poor user experience. Embodiments of the invention described herein address this problem to effectively provide a good user experience and smooth fast forwarding and rewinding of video in voice/video mails. 
       BRIEF SUMMARY OF THE INVENTION 
       [0015]    The invention in its various aspects is defined in the independent claims below to which reference should now be made. Advantageous features are set forth in the dependent claims. 
         [0016]    Arrangements are described in more detail below and take the form of a message storage device configured to store users&#39; messages electronically. The message storage device is configured to interact with a user&#39;s electronic device for transmitting a message to and/or receiving a message from the storage device in a manner dependent on the functionality of the user&#39;s electronic device. Also described is a moving image message processor in which an input moving image message stream including at least one first key frame is processed to include second key frames at a predefined time interval apart. Also described is a message storage device including a controller configured to control movement of encoded video messages to and from a store and a processor depending on at least one predefined condition. 
         [0017]    Embodiments described provide compatibility to users of video telephony equipment to that previously only enjoyed by audio telephony equipment users, and furthermore greatly enhances that functionality with features appropriate to devices with video capabilities. 
         [0018]    In a first aspect of the present invention, there is provided a message storage device configured to store users&#39; messages, the message storage device being configured to interact with a user&#39;s electronic device for transmitting a message to and/or receiving a message from the storage device in a manner dependent on the functionality of the user&#39;s electronic device. 
         [0019]    This arrangement provides a video/voicemail system that may be used with great variation in the functionality of accessing devices or endpoints. 
         [0020]    The message storage device may store messages comprising audio and video. It may interact with a user&#39;s electronic device in a manner dependent on the user&#39;s electronic device comprising: a telephone for transmitting and receiving audio-only messages, or a videophone for transmitting and receiving audio and video messages. If the former, the message storage device may interact with a user&#39;s electronic device such that only audio of a message stored as video and audio is transmitted to the telephone. 
         [0021]    The message storage device may interact with a user&#39;s electronic device in a manner dependent on the user&#39;s electronic device comprising a display configurable by the message storage device, and/or on the display being a touch sensitive display. 
         [0022]    In another aspect of the present invention, there is provided a method for a message storage device configured to store users&#39; messages interacting with a user&#39;s electronic device for transmitting a message to and/or receiving a message from the message storage device, the method comprising: the message storage device interacting with the user&#39;s electronic device in a manner dependent on the functionality of the user&#39;s electronic device. 
         [0023]    In another aspect of the present invention, there is provided a moving image message processor configured to process an input moving image message stream into a processed moving image message stream, the input moving image message stream comprising a first plurality of image frames comprising: at least one first key frame, the or each first key frame comprising a representation of an image decodeable independently of other image frames of the first plurality of image frames; and first frames decodeable dependent on other image frames of the first plurality of image frames; and the processed moving picture message stream comprising: second key frames at a predefined time interval apart, each of the second key frames comprising a representation of an image decodeable independently of other image frames of the second plurality of image frames; and second frames between second key frames decodeable dependent on other image frames of the second plurality of image frames. 
         [0024]    This arrangement effectively provides a good user experience by providing the facility for smooth fast forwarding and rewinding of video in voice/video mails. 
         [0025]    The input moving image message stream may comprise a plurality of first key frames each a different first key frame time interval apart. The different first key frame time intervals may be unpredictable. The predefined time interval between all key frames may be predictable. The predefined time interval may be limited by at least one predefined constraint. 
         [0026]    Key frames of the processed moving picture message stream may each comprise an identifying mark. The moving picture message processor may comprise a generator configured to generate a key frame index comprising an indication of the location of key frames in the processed moving picture message stream. These arrangements provide the facility for quick and accurate fast forwarding and rewinding of video in voice/video mails. 
         [0027]    In another aspect of the present invention, there is provided a method of processing an input moving image message stream into a processed moving image message stream, the method comprising: inputting an input moving image message stream comprising a first plurality of image frames comprising: at least one first key frame, the or each first key frame comprising a representation of an image decodeable independently of other image frames of the first plurality of image frames; and first frames decodeable dependent on other image frames of the first plurality of image frames; and processing the input moving image stream into a processed moving picture message stream comprising: second key frames at a predefined time interval apart, each of the second key frames comprising a representation of an image decodeable independently of other image frames of the second plurality of image frames; and second frames between second key frames decodeable dependent on other image frames of the second plurality of image frames. 
         [0028]    In a further aspect of the present invention, there is provided a message storage device for storing video messages received at the message storage device electronically, the message storage device comprising: a store for storing encoded video messages; a processor for processing encoded video messages; and a controller configured to control movement of encoded video messages to and from the store and the processor depending on at least one predefined condition. 
         [0029]    This arrangement allows a video/voicemail system to handle differences in, for example, screen resolution and video compression protocols in different video-enabled endpoints effectively and efficiently. 
         [0030]    The at least one predefined condition may comprise processing load of the processor, spare storage capacity of the store, the time, capability of a device used to transmit the encoded video message to the message storage device, and/or the size of an encoded video message and/or being based on a feature of a recipient of an encoded video message (the feature may comprise the location of the recipient of an encoded video message) and/or the age of an encoded video message and/or being based on the frequency at which a recipient of an encoded video message has previously accessed the encoded video message and/or at least one capability of at least one device expected to retrieve the encoded video message from the message storage device (this is because the recipient of a message may have used one or more devices to have accessed the message storage device) and/or the history of the video playback capabilities of devices used in past access of the message retrieval system by the recipient. 
         [0031]    The processor may be configured to encode video messages at a plurality of resolutions and/or using a plurality of compression protocols. 
         [0032]    In another aspect of the present invention, there is provided a method of electronically storing video messages received at a message storage device in the message storage device, the method comprising: controlling movement of encoded video messages to and from a store for storing encoded messages of the message storage device and a processor for processing encoded video messages of the message storage device depending on at least one predefined condition. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]    The invention will be described in more detail, by way of example, with reference to the accompanying drawings, in which: 
           [0034]      FIG. 1  is a schematic view of a video communications network including a message storage device embodying an aspect of the present invention; 
           [0035]      FIG. 2  is a flow diagram of call flow for a user using an endpoint to leave a message in the message storage device of  FIG. 1  embodying an aspect of the present invention; 
           [0036]      FIG. 3  is a schematic diagram of part of the message storage device of  FIG. 1  embodying an aspect of the present invention; and 
           [0037]      FIG. 4  is a schematic diagram of another part of the message storage device of  FIG. 1  embodying an aspect of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0038]    An example message storage device or video/voice mail system will now be described with reference to  FIGS. 1 to 4 . 
         [0039]    A communications system  80  including an enterprise network  107  for voice/video communications is illustrated in  FIG. 1 . The network is connected to the external video communications network, via voice or voice and video gateway  106 , 116  using a standard protocol such as H.323 or session initiation protocol (SIP) for Internet transmission  112  (or a proprietary protocol) or via the public switched telephone network  102 . 
         [0040]    A variety of users&#39; electronic devices or endpoints  100 , 101 , 104 , 105 , 108 , 110 , 113  with different functionality are connected to the network  107 . These users&#39; devices include an IP telephone  101  including a video adjunct  100  (described in the US patent application concurrently filed with the present application with the title “A MOVING PICTURE COMMUNICATION SYSTEM” incorporated herein by reference as referred to above), an IP telephone  110  without a camera and with a high resolution colour LCD display, a voice-only IP telephone  104 , a voice only IP telephone linked with a general-purpose computer with an appropriate software plug-in for video calling  105 , a videoconferencing room system  113 , and a video-capable IP telephone  108 , that is to say an IP telephone with a camera and a high resolution colour LCD display. 
         [0041]    A call control system  109  and a video/voicemail system or message storage device  103  are also connected to the network  107 . The video/voicemail system  103  is connected to storage subsystems  114  capable of keeping or storing messages comprising audio and video (video is stored in a compressed format), or audio only. The video/voicemail system  103  also has associated software and protocols for communicating with the video communications network  107 , and endpoints or user devices  100 , 101 , 104 , 105 , 108 , 110 , 113 . 
         [0042]    The video/voicemail system or message storage device  103  is configured to store users&#39; messages electronically on storage sub-system  114 . This storage subsystem may for example be a locally attached disk or array of disks, or a storage area network (SAN) or a network file system. The video/voicemail system is configured to interact with a user&#39;s electronic device or endpoint  100 , 101 , 104 , 105 , 108 , 110 , 113  for transmitting a message to and/or receiving a message from the storage device in a manner dependent on the functionality of the user&#39;s electronic device. 
         [0043]    The video/voicemail system  103  is connected to the call control system  109 . The nature of this connection depends on the type and extensibility of the call control system. It may use either extensions to standard protocols such as H.323 or SIP or may augment the standard protocol connection with a proprietary additional protocol. 
         [0044]    The system  103  may be loosely coupled to an existing standards-based call control mechanism using standard protocols such as H.323 or SIP. In this configuration, existing user-generated signalling mechanisms such as DTMF signalling (using standard telephone keys, namely numerals 0 to 9 as well as “*” and “#”) or the standardized Far-End Camera Control (FECC) videoconferencing protocol (allowing the user to send left/right/up/down/focus messages to the far end of a call) are used to allow control of the video/voicemail system or server by a user. Alternatively, a proprietary protocol is used for communications between the video/voicemail system rather than a standard protocol to provide tight coupling between the call control system  109 , the endpoints  100 , 101 , 104 , 105 , 108 , 110 , 113  and the video/voicemail system  103  to allow the video/voicemail system to interact with an endpoint dependent on the endpoint&#39;s functionality. In this configuration, more advanced signalling mechanisms may be deployed which allow the video/voicemail system better control over the endpoint and thus provide the user with a more intuitive user interface such as a touch-screen graphical user interface (GUI) with which to control the video/voicemail system or server. 
         [0045]    Using the latter configuration, by way of example, the video/voicemail system  103  interacts with an endpoint  100 , 101 , 104 , 105 , 108 , 110 , 113  depending on the endpoint being a telephone  104  for transmitting and receiving audio-only messages, or a videophone  100 , 101 , 105 , 108 , 109  for transmitting and receiving audio and video messages. If the endpoint is a telephone  104  for transmitting and receiving audio-only messages and a message has been stored as audio and video only the audio is transmitted to the telephone. If the endpoint has a display configurable by the message storage device, such as a touch sensitive display or touch-screen, then the video/voicemail system may transmit data for configuring the display, such as to display and provide functionality to buttons for controlling the video/voicemail system such as buttons to fast forward or rewind a video/voicemail message. The video/voicemail system may also interact with an endpoint depending on the screen quality of the endpoint, such as its size, resolution, configuration, aspect ratio, or range of displayable colours as well as the video image formats it can handle. 
       Call Flows 
       [0046]    When a caller places a call to a callee the protocol (H.323 or SIP or another standard or proprietary protocol) enables the caller to request certain media channels (audio and or video), to declare capabilities for decoding different types of media or combinations thereof and to recommend preferences for the types of channels to be opened. If the callee diverts the call to the video/voicemail system then the video/voicemail system will receive this information and can use it to determine what media types are recorded and what video formats, if any, are used. In other words, the functionality of the user&#39;s electronic device is ascertained through information received at the video/voicemail system or message storage device from the user&#39;s electronic device. The functionality may be obtained directly from the information or by inference from the information. 
         [0047]    By way of example, there are several possible procedural flows for the system including the following, which reflect the video/voicemail system interacting with an end point dependent on the functionality of the endpoint. 
         [0000]    Internal Call from Tightly Integrated Video Phone 
         [0048]    This example describes the call flow from an IP telephone  101 . This is a device which is tightly integrated with the call control system  109 , in this example using a proprietary protocol, and therefore allows the call control system and the voicemail system to control the telephone&#39;s user interface (for example the display and “soft” (user-definable) keys). By virtue of the device being tightly integrated, the voicemail system may ask the phone for information about its capabilities and can adjust aspects of the media, such as choice of codecs and image resolution, to suit. In other words, the functionality of the user&#39;s electronic device is ascertained directly through information received at the video/voicemail system. 
         [0049]    A caller using device IP telephone  101  places a call to a callee having a video capable IP telephone  108 . The callee either ignores the call or chooses to divert the call to video/voicemail by pressing a key on their telephone or the call is diverted by policy. The call is then transferred to video/voicemail system  103 . The video/voicemail system plays a pre-recorded video of the called person on the caller&#39;s telephone asking the caller to leave a message. The caller is then guided through the process of leaving a message using on-screen menus and prompts on their IP telephone. The caller can select options using the touch-screen on their telephone  101 . The caller may also be given other on-screen options such as redirecting the call, for example to the callee&#39;s personal assistant (PA) or manager, or re-recording the message. Once a message has been left by the caller, an indication is given on the callee&#39;s telephone  108  to indicate that a message is waiting for them, such as a lamp being lit. 
         [0000]    Call from Loosely Integrated Video Phone 
         [0050]    This example describes the call flow from a standards based video endpoint. This is the most likely call flow for users of H.320 ISDN video endpoints calling into a company via the gateway  106  from the external public switched telephone network  102 , or for users of H.323 video endpoints calling into a company via the gateway  116  from the Internet  112 . The call flow from the two types of gateway  106  or  116  are similar and they are illustrated in the flow diagram in  FIG. 2 . 
         [0051]    Using a standards-based video capable IP telephone, a caller places a call to a callee who has a video-capable IP telephone, via an external voice and video gateway  106  or  116  (reference  202 ). During call setup, the calling standards-based endpoint will send a list of its capabilities. In other words, the functionality of the user&#39;s electronic device is ascertained directly through information received at the video/voicemail system. The list includes types of video and audio codecs, available image resolutions and permitted combinations thereof. The callee either ignores the call or chooses to divert the call to voicemail by pressing a key, or the call is diverted by policy. The call is then transferred to the video/voicemail system  204 . The information about the caller&#39;s device capabilities are either retransmitted by the caller&#39;s endpoint during the call transfer process, or they are kept by the call control system and passed to the video/voicemail system during the call transfer process. This allows the video/voicemail system to know the capabilities of the caller&#39;s endpoint and to adjust the video recording codec parameters accordingly. 
         [0052]    The video/voicemail system then plays a pre-recorded video (including audio) of the called person asking the caller to leave a message  206 . The caller is then guided through the process of leaving a message using on-screen menus and prompts. The caller may select options using the DTMF keys on their telephone. The video/voicemail system may also allow the user to control the process of leaving messages using the far end camera control protocol (FECC) found as part of the video calling standard (e.g. H.323 or SIP). 
         [0053]    The caller may also be given other on-screen options such as redirecting the call, for example to the callee&#39;s PA or manager, or re-recording the message. A video of the caller (including audio) is streamed to the video/voicemail system and recorded by the video/voicemail system  210 . Once a message has been left by the caller, the message storage device or video/voicemail system transmits to the user&#39;s electronic device or telephone an indication that a message has been received. In response, an indication is given on the callee&#39;s telephone to indicate that a message is waiting for them, such as a lamp being lit  212 . Optionally, an electronic video file (including audio) may be sent by e-mail to the callee  214 . 
         [0000]    Call from Audio-Only Phone 
         [0054]    This example describes the call flow from a traditional audio-only telephone. This may be an internal telephone  104 . This is also the most likely call flow for users of conventional telephones calling into a company via the gateway  106  from the external public switched telephone network  102 , or for organisations using audio-only Internet Telephony calling into a company via the gateway  116  from the Internet  112 . If a user calls in from the PSTN, the gateway  106  will know that the caller is on a voice-only device because of the telephony signaling used or because of the physical connection that the gateway has. This information is passed to the call control system  109 . If a user calls in from the Internet or from an internal telephone  104 , the call setup information contains only voice capabilities, so the call control system  109  will know that it is a voice-only call. From this point onward, the call flow from the two types of gateway  106  or  116  or from an internal telephone  104  are similar. 
         [0055]    Referring back to  FIG. 1 , a caller using a voice-only (audio-only) IP telephone  104  places a call to a callee who has a video-capable IP telephone  108 . The callee either ignores the call or chooses to divert the call to voicemail by pressing a key or the call is diverted by policy. The call is then transferred to video/voicemail system  103 . The video/voicemail system plays either the audio from a pre-recorded video or a separate audio recording of the called person asking the caller to leave a message. The caller is then guided through the process of leaving a message using voice prompts. The caller may select options using the DTMF keys on their telephone. The caller may also be given other spoken options such as redirecting the call to the callee&#39;s PA or manager, or re-recording the message. Once a message has been left by the caller, the message storage device or video/voicemail system transmits to the user&#39;s electronic device or telephone an indication that a message has been received. In response, an indication is given on the callee&#39;s telephone to indicate that a message is waiting for them, such as a lamp being lit  212 . 
         [0000]    Message Retrieval from Tightly Integrated Video Phone 
         [0056]    A caller using a video-capable IP telephone  108  dials in to video/voicemail system  103 . Video/voicemail system offers an interactive graphical user interface (GUI) to the user on the touch-screen of their telephone  108 . The GUI provides access to new messages, saved messages and the folder hierarchy. It also provides access for configuration of the behaviour of the video/voicemail system for example with regard to handling of incoming messages. The caller selects a message using a touch-screen on their telephone. The video/voicemail system plays the video and audio of the selected message. The telephone  108  provides graphical means for instructing the video/voicemail system to seek within a message during playback. Telephone  108  provides graphical means for instructing the video/voicemail system  103  to forward the message to other mailboxes. The GUI for forwarding a message may include integration with enterprise or local directory systems such as LDAP.