GB2512140A

GB2512140A - Messaging system and method

Info

Publication number: GB2512140A
Application number: GB1305322.8A
Authority: GB
Inventors: Sacha Cato
Original assignee: CLASSFIEDAPP Ltd
Current assignee: CLASSFIEDAPP Ltd
Priority date: 2013-03-22
Filing date: 2013-03-22
Publication date: 2014-09-24
Also published as: GB201305322D0

Abstract

A system and method for handling electronic messages, particularly instant messages, in a messaging system in a way which preserves the privacy of all users of the system. In prior art systems screenshots may be taken while messaging sessions are taking place, which may go undetected. This is a particular problem for systems such as Snapchat (RTM) and Facebook (RTM) Poke which rely on the messages to be auto-deleted once they have been viewed 8210, 8212 and so senders can rely on implied privacy of content they share. A secure method of detecting whether a screenshot has been taken on a device 8206b is disclosed comprising: managing the display of messages in messaging software installed on an electronic device, said electronic device connectable to a network of other electronic devices and arranged to display 8208 on a screen messages received from other electronic devices, wherein said electronic device includes an image memory for storing images and meta data relating to the images, the meta data including a time-stamp indicating the time when the image was captured, said electronic device being further capable of capturing a screen shot of an image displayed on the screen and storing the screen shot image and meta data including a time-stamp in the image memory, the method comprising the steps of; recording initial-state data, said initial-state data representing the state of the electronic device when the display of messages is initiated, recording later-state data representing the state of the electronic device after a message is displayed, comparing 8213, 8213b the initial-state data with the later-state data and indicating that a screen shot image has been captured based on the results of the comparison 8115, 8213c. The comparison may involve comparing the number of images in a particular image folder at initial state time and later-state time. The comparison may also or alternatively involve checking for images with time-stamps later than an initial state time etc. If screenshots are detected to have been taken the user may be exited and logged-out/blocked from the messaging application 8213d. An alert may also be sent to the sender of the message that was potentially screenshot captured 8213c. A further embodiment is also disclosed to prevent screenshots being taken using external devices, e.g. an external camera, such that messages are displayed with watermarks 8209 which are displayed so as to obscure the messaging content for particular timing instruction period(s).

Description

MESSAGING SYSTEM AND METHOD

BACKGROUND

Technical Field of the Invention

The invention is in the field of communications, particularly the electronic communication of instant messages. The invention relates to a system and a method for handling electronic messages in a messaging system in a way which preserves the privacy of all users of the system.

Description of Related Art

The internet supports many ways for people to communicate with one another. One method is instant messaging, where users can send messages almost instantly to each other. Initially instant messaging was limited to personal computers but increases in wireless bandwidth and mobile processing power has meant that it is possible to send instant messages between mobile devices that can be connected to the internet. An instant messaging service architecture may include a messaging as software application, or client, running on the sender's network connected electronic device, a similar messaging software client running on the recipient's network connected electronic device and a messaging server within the network to coordinate the transmission of messages between sender and recipient. A subscriber to an instant messaging service is able to compose a message, attach files, including photos, video, audio or other types of data and send it to another subscriber to the messaging service. The recipient can reply and attach their own files in response. Users can also share pictures, videos and audio files to external social networking accounts. It is desirable for a subscriber to know that a message sent to the recipient will not be seen by anyone else but the intended recipient. The recipient's messaging software client may be arranged to prevent the message being forwarded or copied and to delete the message after being read by the sender. An example of a messaging system which can delete messages after being read is described in US 2009248751.

Many mobile devices or computers are able to take "screen shots", whereby a user can request the device to capture and store an electronic copy of the image currently being displayed on the screen. While the data which comprises a message can be deleted by the recipient's messaging software, an image of the message captured by taking a screen shot cannot be so easily deleted. This presents a problem because a screen shot of a message could compromise the privacy of the message.

A known messaging system is provided by SnapchatTM for sharing photographs between subscribers, and deletes messages including the photos after up to 10 seconds. The recipient must keep their finger on a button to view the message which prevents them from operating the screenshot function. A similar system is provided by Facebook PokeTM.

However, keeping a finger on the screen while reading a message is inconvenient and also unreliable as it does not ensure that a screenshot has not been taken.

SUMMARY OF THE INVENTION

The invention therefore provides a computer implemented method for managing the display of messages in messaging software installed on an electronic device, said electronic device connectable to a network of other electronic devices and arranged to display on a screen messages received from other electronic devices, wherein said electronic device includes an image memory for storing images and meta data relating to the images, the meta data including a time-stamp indicating the time when the image was captured, said electronic device being further capable of capturing a screen shot of an image displayed on the screen and storing the screen shot image and meta data including a time-stamp in the image memory, the method comprising the steps of; recording initial-state data, said initial-state data representing the state of the electronic device when the display of messages is initiated, recording later-state data representing the state of the electronic device after a message is displayed, comparing the initial-state data with the later-state data and indicating that a screen shot image has been captured based on the results of the comparison.

The initial-state data may be the time when the message display is initiated and the later-state data may be the time-stamp of images stored in the image memory, and wherein the method may further include the step of indicating that a screen shot image has been captured if the comparison step determines that the time-stamp of an image stored in the image memory is later than the time when the message display was initiated. This would indicate that an image in the image memory was captured while the message was being displayed and therefore that the image is a screen shot of the message.

The initial-state data may be the time when the message display is initiated and the later-state data may be the time-stamp of the last image to be stored in the image memory, and wherein the method may further include the step of indicating that a screen shot image has been captured if the comparison step determines that the time-stamp of the last image stored in the image memory is later than the time when the message display was initiated.

The initial-state data may be the time-stamp of the last image to be stored in the image memory and the later-state data is also the time-stamp of the last image to be stored in the image memory, the method may further include the step of indicating that a screen shot image has been captured if the comparison step determines that the time-stamp recorded as the later-state data is later than the time-stamp recorded as the initial-state data.

The initial-state data may be the number of images stored in the image memory and the later-state data may be the number of images stored in the image memory, and wherein the method may further include the step of indicating that a screen shot image has been captured if the comparison step determines that the number of images recorded as the later-state data is greater than the number of images recorded as the initial-state data.

The initial-state data may include one or more components selected from a list including the time when the message display was initiated, the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and the later-state data includes one or more components selected from a list including the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and the method may further include the step of comparing components of the initial-state data with equivalent component of the later-state data.

The method may include the steps of performing a first comparison of an initial-state component with an equivalent later-state component, and if a screen shot image is detected then performing one or more check comparisons between the other initial-state components and later-state components, and indicating that a screen shot image has been captured if the check or checks performed by the comparator determine that a screen shot image is present in the image memory after the message is displayed.

The method may include the step of recording the later-state data when a message or messages are no longer displayed on the screen and/or periodically while a message or messages are displayed on the screen.

The method may include the step of recording the later-state data periodically while a message or messages are displayed on the screen and performing comparisons with the initial-state data to detect a screen shot image of the screen while a message or messages are displayed.

The electronic device may be capable of running multiple software applications, such that at any one time the screen may display an image produced by the software running in the foreground, and the method may include the step of recording later-state data if the messaging software is put into the background.

The method may include the step of exiting the messaging software when it is indicated that an image of the screen has been captured while the message was being displayed on the screen. This acts as a strong deterrent for the recipient not to take a screen shot of the message.

The method may include the further steps of receiving a message which includes primary message content and secondary message content, wherein the secondary message content includes data representing a secondary image and a timing instruction, displaying the primary message content on the screen of the electronic device, superimposing the secondary image over the primary message content for a duration determined by the timing instruction. The secondary image is a watermark and the timing instruction allows the watermark to be displayed according to timing rules set by the sender and included in the message. This makes it more difficult for the recipient to take a screen shot because of the uncertainty of when the message will disappear and re-appear.

The timing instruction may include a duration for displaying the secondary image.

The timing instruction may include a secondary image display repeat value, for determining if and when to repeat the display of the secondary image.

The method may include reading a primary message view time, for determining how long to display the primary message for, displaying the primary message for the primary message view time and deleting the primary message from the memory of the electronic device after the primary message view time has expired. This ensures that no record of the message is left with the recipient that could be copied and distributed against the wishes of the sender.

The method may include composing a message which includes primary message content for displaying on the screen of an electronic device, and secondary message content including a secondary image for obscuring the primary message content, said secondary message content further including timing instructions for determining the duration of display of the secondary image. The messaging software therefore has functionality to compose messages which can include a controllable watermark feature.

The method may comprise the step of providing a primary message view time for determining how long to display the primary message for.

In a further embodiment of the invention, a computer implemented messaging program is provided for use with an electronic device connectable to a network of other electronic devices, said messaging program arranged to display messages received from other electronic devices on a screen of the electronic device, wherein said electronic device includes an image memory for storing images and meta data relating to the images, the meta data including a time-stamp indicating the time when the image was captured, said electronic device being further capable of capturing a screen shot of an image displayed on the screen and storing the screen shot image and meta data including a time-stamp in the image memory, wherein the messaging program includes a screen shot detector for detecting when a screen shot image has been captured, said screen shot detector comprising; a state recorder for recording initial-state data, said initial-state data representing the state of the electronic device when the display of messages is initiated, and later-state data representing the state of the electronic device after a message is displayed, a comparator for comparing the initial-state data with the later-state data and an indicator for indicating that a screen shot image has been captured based on the output of the comparator.

The initial-state data may be the time when the message display is initiated and the later-state data may be the time-stamp of images stored in the image memory, and wherein the indicator is arranged to indicate that a screen shot image has been captured if the comparator determines that the time-stamp of an image stored in the image memory is later than the time when the message display was initiated.

The later-state data may be the time-stamp of the last image to be stored in the image memory, and wherein the indicator may be arranged to indicate that a screen shot image has been captured if the comparator determines that the time-stamp of the last image stored in the image memory is later than the time when the message display was initiated.

The initial-state data may be the time-stamp of the last image to be stored in the image memory and the later-state data may also be the time-stamp of the last image to be stored in the image memory, and wherein the indicator is arranged to indicate that a screen shot image has been captured if the comparator determines that the time-stamp recorded as the later-state data is later than the time-stamp recorded as the initial-state data.

The initial-state data may be the number of images stored in the image memory and the later-state data may also be the number of images stored in the image memory, and wherein the indicator is arranged to indicate that a screen shot image has been captured if the comparator determines that the number of images recorded as the later-state data is greater than the number of images recorded as the initial-state data.

The initial-state data may include one or more components selected from a list including the time when the message display was initiated, the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and the later-state data may include one or more components selected from a list including the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and wherein the comparator may be arranged to compare components of the initial-state data with equivalent component of the later-state data.

The comparator may be arranged to perform a first comparison of an initial-state component with an equivalent later-state component, and if a screen shot image is detected then the comparator may be arranged to perform one or more check comparisons between the other initial-state components and later-state components, and the indicator may be arranged to indicate that a screen shot image has been captured if the check or checks performed by the comparator determine that a screen shot image is present in the image memory after the message is displayed.

The state data recorder may be arranged to record the later-state data when a message or messages are no longer displayed on the screen and/or periodically while a message or messages are displayed on the screen.

The state data recorder may be arranged to record the later-state data periodically while a message or messages are displayed on the screen.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawings, in which: Figure la is a schematic diagram showing the arrangement of a known messaging system which allows messages to be sent between mobile devices.

Figure lb is a schematic diagram showing the arrangement of a known messaging system which allows messages to be sent between computer terminals.

Figure 2a is a schematic diagram showing the front exterior of a mobile device of the type shown in Figure la.

Figure 2b is a schematic diagram showing the rear exterior of a mobile device of the type shown in Figure la.

Figure 2c is a schematic diagram showing the hardware components of a mobile device of the type shown in Figure 1 a.

Figure 3 is a schematic diagram showing the software components of a mobile device of the type shown in Figure 1 a.

Figure 4 is a schematic diagram showing the functional elements of a messaging software client in accordance with an embodiment of the invention.

Figure 5 is a schematic diagram showing the functional elements of a messaging software server in accordance with an embodiment of the invention.

Figure 6 is a flow diagram showing the stages involved in setting up a messaging system in accordance with an embodiment of the invention.

Figure 7 is a flow diagram showing the stages involved in sending a non-secure message in accordance with an embodiment of the invention.

Figure 8a is a flow diagram showing the stages involved in sending a secure message in accordance with an embodiment of the invention.

Figure 8b is a flow diagram showing the stages involved in displaying a secure message to the recipient.

Figure 9a is a flow diagram showing how the screen shot detector works in the messaging mode.

Figure 9b is a flow diagram showing how the screen shot detector works for a secure message.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Increases in available wireless bandwidth have enabled mobile access to the internet and the possibility to send messages of significant size between suitably enabled equipment. Messages can be text, photos, video, audio tiles or a combination otformats. Atypical mobile messaging system is shown in Figure la; a similar system could be implemented using computers connected to the internet as shown in Figure lb. A messaging service is usually hosted by messaging service provider software residing on server 104a, which is connected to the internet 103.

The server 104a provides management functionality, such as storing user contact information and may store messages as back-up or in case there are connection problems between users. Mobile device lOla, such as a smartphone or PDA is provided with messaging application software, otherwise known as a messaging software client or messaging application or messaging client, is arranged to allow a user to compose messages, make attachments etc, and transmit messages to a recipient lOlb via the internet 103 using a protocol such as TCP/IP. The server 104a can assist with routing the messages and other servers 104b can be used to provide presence information relating to users of the system.

A typical mobile device is shown in Figure 2. The mobile device 101 includes a frame and protective covers 201, a screen 202, which may be touch sensitive.

Software buttons may be displayed on the screen 202 and thereby provide an input means to allow the user to interact with the device. Hardware buttons 204 may be provided for a user to interact with the device, as well as a microphone 205 a speaker 206 and a camera 207. The device may include a power supply 208 for powering the systems of the device and a processor 209 for executing software.

The processor 209 is in communication with a non-volatile memory means 210 such as flash memory for storing software and other data. The non-volatile memory means 210 may be divided into regions, for example regions for storing software applications, regions for storing the data generated by the software applications.

These regions may be password protected if necessary to provide secure storage areas. The processor 209 may also be in communication with a volatile RAM memory means 211. The processor is also able to communicate with a data transmit and receive module 212 which handles interfacing with the communication network.

The processor 209 is able to execute a number of software applications, as shown in Figure 3. The first software layer is the operating system 301 which interfaces with the hardware components of the device, including the display 202, user inputs 204, data transmit and receive 212, volatile 211 and non-volatile memory 210 and the processor 209. The second software layer is the user interface toolkit 302 which provides an interface with the operating system 301. A library of common routines 303 may be provided for executing common functions. The third layer includes software applications 304a, 304b etc which can be run on the mobile device.

Software applications can perform many functions, and are created by independent developers as well as by the operating systems providers. Standard software applications may be provided by the operating systems providers for managing contacts in an address book, email applications and calendar functions for example.

To preserve interoperability and functionality and indeed the user's property, the way that a software application interacts with the device is tightly controlled by interface rules set out by the operating system providers. These rules determine, for example what data can be written, stored or deleted in the memory and by whom.

An embodiment of the invention is a software application for installing on two or more mobile devices (such as a smartphone or tablet computer) or on a personal computer, which can provide a messaging functionality between the devices which subscribe to the service. The invention is not limited in application to these devices and other electronic devices may be used. The software application has to comply with the rules and regulations of the operating system provider. Providers include iOSTM, Android1M, BlackberryTM, NokiaTM, Windows PhonelM, SymbianTM, BadaTM among others. The messaging functionality includes the ability to provide dual messaging functionality: a normal chat function and then, if required, switching to a secure messaging function. The secure messaging function has features which help to prevent messages which are intended for a specified recipient or a group or groups from being seen by anyone against the wishes of the sender, including a screen shot detector and a controllable watermark feature.

While a sender can request that a message be deleted by the recipient's messaging software, an image of the message captured by taking a screen shot cannot be so easily deleted because it is stored in the camera roll section of the memory. It is generally not permitted by OS provider rules for a software application to interfere with data stored by another software application. An embodiment of the invention can detect whether a screenshot has been taken. The sender can be notified and if necessary the recipient can be logged out of the service and blocked from using the service again.

Visual watermarks are conventionally overlaid over a photo or text or other media to identify the owner and! or present a copyright notice. In an embodiment the watermark can be used to obscure a part or all of a message for a given length of time, making it less meaningful for a recipient to take a screenshot or a physical picture of the screen using a separate camera.

The system requirements for an embodiment of the invention require two or more devices. In the description below the devices are mobile devices, but may also be personal computers. The mobile devices are able to communicate with one another using the internet using a server to provide the messaging management, as in the conventional messaging system shown in Figure la.

A messaging software application is provided on each of the subscribing devices, the messaging application software having a structure as shown in Figure 4. The software application includes a manager routine 401 for handling data flow. The manager routine 401 is able to receive input from a data receiver component 402 which is arranged to receive data and decrypt encrypted messages. The manager 401 is also able to send data to a data send component 403, which is able to encrypt messages and to add header information for message routing. The manager 401 is also in communication with an address book interface 404 which is arranged to read data from an existing address book. The manager 401 is also able to receive data from a message composer 405 and a memory interface 406, which can access the various memory areas of the device including general areas 406a such as the camera roll, photo, video and audio files. The message composer 405 can also access a message attribute setter 407 for setting the features of the message, as discussed in more detail below. The manager 401 may read and write data to dedicated message application memory space 406b, which may be password protected and can include user interface pages for display, a message store, watermark templates etc. All non-destructable! secure files exchanged between users of the secure messaging software application are stored in this dedicated memory 406b. The manager is able to send data to display interface 408 which can display messages; the messages can be photos, text, or video or audio, etc; the display interface is arranged to reproduce messages in any of these formats. The manager 401 can also receive data from the user input interface 409, which is able to receive input from the hard and soft buttons of the device, allowing users to make selections, type messages etc. The manager also may also refer to a security module 410 for verification of user identity, passwords etc. The manager 401 is also in communication with a screen shot detector 411. The screen shot detector 411 is able to record the time and date at which a message is visible on the screen of the device, and capable of being captured as a screen shot. The screen shot detector 411 is also capable of communicating with the memory area of the device 406a where screen shots are stored. The screen shot detector 411 can determine attributes of the stored images, including the number of images stored in the memory area and the time and date when the images were taken.

The arrangement of the server 104 is shown in Figure 5. A message server manager 501 is provided to coordinate sending, receiving and storing messages sent between the service subscribers. The message service manager 501 can receive data from a data receiver 502 and send data from a data sender 503. The data receiver and sender remove and attach header information for routing purposes. The message service manager 501 can create subscriber records 504a, 504b in a database. In Figure 5, only a single full subscriber record 504a is shown; other records are shown in dotted outline to indicate that there are many such records. Each record can include stored messages 505, security details 506, login details 507, blocked status 508 and addresses of other subscribers 509. A separate address record 510 may be kept of all of the service subscribers. The message service manager 501 is also able to retrieve the client software application from a memory space 511 for sending to the client on request.

Setting up an embodiment of the messaging service is shown in Figure 6. A user who wishes to subscribe to the secure messaging service first requests the service from the server (Step 6101). This may be by navigating to the secure messaging service provider's website using a suitable web browser installed on the client device 101, and selecting an option to join. The server detects the request (Step 6201) and pushes the client application software to the client Step (6202), whereupon it is installed on the client device by the client device operating system and executed.

Installation includes setting up a dedicated secure memory area 406b in the device memory 210 and loading user interface pages and various message templates into this memory, including an encryption key. The encryption key is one of a pair which can be used to encrypt messages and for recipients to decrypt encrypted messages.

The manager 401 then causes welcome pages to be retrieved from the memory 406b and displayed by the client display interface 408. Information entry pages may be displayed for the new user to enter information (Step 6103) Such information may include a username, location, date of birth, email address, telephone numbers including mobile phone, gender, interests etc. The user may be given the option to allow the software application access to their general address book (Step 6104). If this option is declined, contact details for recipients are entered manually for each message sent. If this option is accepted, the address book interface 404 is enabled to copy contact details from the address book and send these to the server (Step 6105) where other subscribers can be identified from the address database 510.

Contacts in the new subscriber's address book who are also registered to the secure messaging service can then be highlighted. To complete the registration process the server is arranged to send a FIN verification code to the new subscriber's handset by SMS message (Step 6204) using the mobile telephone number provided during registration. The new subscriber then enters the PIN number in the software application interface (Step 6108) which is then sent back to the server (Step 6109) for confirmation (Step 6205). When the correct PIN is entered a new subscriber record is set up (Step 6206). Any messages that from other subscribers to the new subscriber that have been queued are then forwarded to the new subscriber (Step 6207).

The use of the messaging service is described with reference to Figure 7. There are various ways in which a user can send a message using the present messaging service. The user may initiate a new message thread with another user who may or may not be subscribed to the service. Alternatively the user may wish to reply to a message from another secure message service subscriber. The message that the subscriber chooses to send may be a non-secure chat message or a secure, classified message. Figure 7 shows the sequence involved in sending a message.

Firstly the sender selects a recipient, who may be an individual or a group of people.

If the message is the first in a thread the sender can choose the recipient or recipients from the address book, or enter contact details directly if the address book is not available. If the recipient is not a secure message service subscriber then an SMS message or an email can be sent to the recipient noting that they have a message waiting and providing instructions on how to subscribe. When the message is sent it is stored by the server and queued until the recipient is registered.

If the new message is a response to a previous message, the contact details for the recipient or recipients will already be available. The user can then select the type of message that they wish to send (Step 7102), either a non-secure message or a classified secure message. Non-secure messages are available to view for as long as required by both parties and have no security features. This makes them quick and easy to send because they do not require a lot of processing. Secure messages can have security features which can ensure that the contents remain private.

When the user wishes to send a message, or if the user is replying to a message, a messaging mode is entered. If the user selects a non-secure message the message composer 405 is used to compose the message and attach files if required (Step 7105). The message is then passed to the sender 403 where a header is applied specifying recipient address and sender identity. The message is then sent (Step 7106) to the server where it is stored and forwarded to the recipient client software application running on the recipient's device (Step 7201). The recipient is notified of the arrival of a new non-secure message (Step 7202), on the screen if their application software is open or against the sender in their list of contacts.

Notification may be sent by the recipient that the message has been received and the sender can be shown a message status "received" notification (Step 7107). The recipient may choose to open the message (Step 7205) which is then displayed (Step 7204). Notification may be sent by the recipient that the message has been read and the sender can be shown a message status "read" notification (Step 7107).

The recipient may then choose to reply to the message (Step 7205) in which case the message composer 405 of the recipient client software application (which is the same software as used by the sender and other subscribers) is invoked to compose a message (Step 7206). The message is then passed to the sending routine 403 which attaches headers and sends the complete message to the server (Step 7207), where it is saved and forwarded to the intended recipient or recipients (Step 7108) and displayed (Step 7109).

If a user chooses to create a secure message (Step 7104) a different sequence is invoked, as shown in Figure 8. This secure-message functionality can be provided within the framework of the non-secure system, where a user can be using the non-secure messaging service and then opt to send a message which is secure.

Alternatively the secure messaging function can be provided separately. The message compose routine 405 is used to compose a message (Step 8101), which may be text or files. Then the message attribute setting routine 407 is used to display a number of options (Steps 8102 to 8104). These options include: security settings (Step 8102), such as a security question and answer that will be known by, or is communicated in another way to, the recipient; the duration for which the message will be displayed and how many times the message may be viewed (Step 8103); the option to include a watermark and the option to set watermark behaviour attributes (Step 8104) (discussed in more detail below);. Other attribute functionality could be added if required. The order in which these options are provided to the sender may be changed, for example setting the watermark may be performed prior to setting the security. The message may then be previewed (Step 8105) if required, which will show the sender how the message will appear to the recipient, including the behaviour of the watermark. The sender can edit the message again before sending. The message can then be permanently stored in the secure memory area 406b of the device, if required by the sender. The message is then sent to the sending routine 403, which detects that the message is a secure message. The sending routine then encrypts the message (Step 8106) using one of the key pairs and adds the attribute data to the message, including the watermark and watermark behaviour, security questions, message view time and number of permitted views (Step 8107). A header is then added (Step 8108) which identifies the sender and recipient and an envelope added (Step 8109) to define the message contents and finally communications protocol data is added (Step 8110) by the operating system to correctly route the message to the server. The message is then sent to the server. The message is received by the receive routine 502 (Step 8301) where headers are removed and the sender identified. The message is copied to the sender record (Step 8303). The message service manager 501 is arranged to identify the recipient and forward the message to the recipient using the stored email address or other information (Step 8304).

The message is received by the receiver routine 402 of the recipient software application (Step 8201) where it is decrypted and the sender identified. The message is sent to the manager 401 which then stores the message in the secure memory of the device 406b. A notification of message receipt is displayed (Step 8202). A confirmation of receipt and time of receipt is sent to the server (Step 8203) and the receipt confirmation details are forwarded to the sender (Step 8305), where they are displayed (Step 8107). The recipient can then decide whether to open the message (Step 8204) and when the decision is made the security question is displayed (Step 8205). The user input in response to the question is detected by input interface 409 and the results passed to the manager 401. If the answer given by the recipient matches that in the message attributes then the message is displayed, as shown in the continuation flow chart in Figure 8b. If the answer is wrong, the message is not displayed and the sender notified that the security question has been incorrectly answered and received message may be deleted from the client memory 406b.

Prior to opening and displaying the message (Step 8206c) the messaging mode may be entered (Step 8206a), if the recipient is not already in the messaging mode.

Messaging mode is a window which displays all of the messages in a thread from a particular sender, and allows the creation of a response, or if there are no messages in a thread, then the creation of a new message. The screen shot detector 411 may be activated at this point (Step 8206b) and periodically query the image memory (Step 8213). The time and date of opening is recorded (Step 8207) and notification sent to the sender (Step 8113). The message is displayed by the display interface 408 for the length of time specified in the attributes, and may be from 1 second to 20 seconds or any other length of time (Step 8208) While the message is displayed the watermark is displayed by the display interface 408 according to the rules specified by the sender in the watermark behaviour attributes (Step 8209).

The number of times that the message is displayed is counted by the manager 401 (Step 8211). The message is deleted from the memory 406b when the number of view times is reached (step 8212).

The screen shot detector 411 may be activated when the user enters the messaging mode or when a classified message is displayed or visible. Figure 9a shows the operation of the screen shot detector 411 when the message mode is entered. This can be used to detect a screen shot while any message is displayed, secure or non-secure. The screen shot detector 411 detects when the message mode is entered (Step 9101). At this point, specified information is recorded (Step 9102). This specified information may be the time at which the message mode was entered, an indication that message mode is active, the time-stamp of the last image in the image memory 406a and/or the number of images in the image memory. Images in the image memory 406a may be stored there either by storing an imported image, by taking a photograph with the inbuilt device camera 207 or by capturing a screen shot of the current display. The screen shot detector may also detect when the messaging mode is exited (Step 9103) and then query the image memory 406a (Step 9105) to obtain information such as the time-stamp of the last image in the image memory and/or the number of images in the memory. This query may be performed periodically while in the messaging mode (Step 9104), so that a screen shot event may be detected in a timely way. Periodical querying may be performed for example every millisecond, or every second or at any other interval to provide a timely notification of a screen shot event, without unnecessarily overloading the processor. The query results are compared with the specified information (Step 9106) and if a screen shot is detected the sender, recipient and server are notified (Step 9107). A warning is displayed by the sender's software application that a screen shot of the message has been taken (Step 8115). The recipient is logged out of the software application and the server then puts a block in the recipient's record which prevents that user from logging into the service again (Step 821 3d).

The screen shot detector may be arranged to record the message mode entry time and to query the time-stamp of the last image in the image memory 406a. If the time-stamp is later than the time that the message mode was entered, this indicates that the image is a screen shot of the screen while in the message mode, which may be a breach of the terms of use of the messaging service.

Alternatively the screen shot detector 411 may be arranged to count the number of images in the image memory 406a when the messaging mode is entered, and to subsequently query the number of images present in the image memory 406a. If the number of images in the image memory is greater while in the messaging mode or immediately after exiting the messaging mode, then this indicates that a screen shot has been taken and appropriate action can be taken as described above.

Alternatively, the time when the messaging mode is entered can be recorded and the number of images in the image memory 406a also recorded when the messaging mode is entered. If it is found by subsequent querying of the number of images present in the image memory 406a that the number of images in the image memory 406a has increased while in the messaging mode, the time that the extra images were taken can be checked. If it is found that these images were captured while in the messaging mode, it is concluded that a screen shot of the message has been captured and appropriate action can be taken as described above.

Alternatively, the screen shot detector 411 may only be activated when a classified message is opened, as shown in Figure 9b. In this instance the time during which the message is visible is recorded (step 9203), i.e. while the watermark is not obscuring the message contents, or if there is no watermark or the watermark is translucent, every time the message is displayed. The time during which the message was visible provides a time window for comparison with the time stamp on the images in the image memory 406a. The number of images in the image memory 406a may also be counted and if the number of images increases while the secure message is visible (i.e. message content displayed without an opaque watermark, or displayed with a translucent watermark) then the time when the extra images were taken is detected and compared with the time window.

The messaging client may be running alongside other software applications on the operating system. It is possible for a user to put the messaging client into the background and another software application run and displayed on the mobile device, and a screenshot of this application captured. If the messaging client is then brought back to foreground and the image memory queried by the screen shot detector 411, a new image in the image memory 406a will be detected and this will be falsely attributed as a screenshot of the current message. To prevent this false detection, before the messaging client is sent to the background, the messaging mode is exited, or the secure message is exited and the image memory 406a queried. This has the effect of closing the time window and only counting images in the image memory 406a while messages are displayed on the screen and able to be captured.

The watermark behaviour attributes are included with the message as separate data.

Watermarks can be selected from a library of templates stored in the secure memory area 406b for the software application. Further watermarks can be downloaded to the device if required. Watermarks are an electronic file representing an image which can be overlaid over the message and therefore visible on the screen, and may comprise a copyright notice or a design which characterises the sender in some way. The attribute setter 407 is used to select a watermark from the library, and to determine the position of the watermark in relation to the message. If the message is a video then the watermark can be displayed for the duration of the video. The opacity of the watermark can be set, so that the message is clearly visible through the watermark or not visible at all. The time that the watermark first appears and the time that the watermark disappears can be set. For example, the message may be initially displayed full obscured by an opaque watermark for 5 seconds, then the watermark may be set to disappear for 5 seconds to reveal the message, and then the watermark appears for another 5 seconds. Then the message itself can disappear and possibly be deleted from the recipients device altogether, unless the message is allowed to be viewed more than once. The appearing and disappearing watermark helps to prevent the recipient from taking a screen shot of the message or a picture of the message with another device as it may be difficult to predict if or when the message is going to be visible. The message data package includes primary content, which is the message itself and secondary content which is the watermark and attributes, the attributes including the watermark timing instructions.

Messages can include attachments such as pictures, videos, audio files etc. These files can be stored in the client application memory area and may be shared on external social networking accounts. These files are saved in a secure memory area of the electronic device which is dedicated to the messaging software. When a screenshot is captured it will not appear in these files, but in the general image memory area, sometimes referred to as the camera roll.

Mobile electronic device are often syncronised with personal computers, whereby data stored in the memory of the mobile device can be transferred to the memory of the personal computer. The data that can be transferred can be pre-determined by the messaging software application developer so that only specific types of data can be transferred. For example, photographs, videos and audio files may be freely transferred, while data representing messages can be prevented from being transferred. It is to be understood that various modifications to the preferred embodiment and the generic principles and features described herein will be readily apparent to those skilled in the art. Thus, the present invention is not intended to be limited to the embodiment shown and such modifications and variations also fall within the spirit and scope of the appended claims.

Claims

Claims 1. A computer implemented method for managing the display of messages in messaging software installed on an electronic device, said electronic device connectable to a network of other electronic devices and arranged to display messages received from other electronic devices on a screen, wherein said electronic device includes an image memory for storing images and meta data relating to the images, the meta data including a time-stamp indicating the time when the image was captured, said electronic device being further capable of capturing a screen shot of an image displayed on the screen and storing the screen shot image and meta data including a time-stamp in the image memory, the method comprising the steps of; recording initial-state data, said initial-state data representing the state of the electronic device when the display of messages is initiated, recording later-state data representing the state of the electronic device after a message is displayed, comparing the initial-state data with the later-state data and indicating that a screen shot image has been captured based on the results of the comparison.
2. A method in accordance with claim 1, wherein the initial-state data is the time when the message display is initiated and the later-state data is the time-stamp of images stored in the image memory, and wherein the method further includes the step of indicating that a screen shot image has been captured if the comparison step determines that the time-stamp of an image stored in the image memory is later than the time when the message display was initiated.
3. A method in accordance with claim 1, wherein the initial-state data is the time when the message display is initiated and the later-state data is the time-stamp of the last image to be stored in the image memory, and wherein the method further includes the step of indicating that a screen shot image has been captured if the comparison step determines that the time-stamp of the last image stored in the image memory is later than the time when the message display was initiated.
4. A method in accordance with claim 1, wherein the initial-state data is the time-stamp of the last image to be stored in the image memory and the later-state data is also the time-stamp of the last image to be stored in the image memory, the method further including the step of indicating that a screen shot image has been captured if the comparison step determines that the time-stamp recorded as the later-state data is later than the time-stamp recorded as the initial-state data.
5. A method in accordance with claim 1, wherein the initial-state data is the number of images stored in the image memory and the later-state data is also the number of images stored in the image memory, and wherein the method further includes the step of indicating that a screen shot image has been captured if the comparison step determines that the number of images recorded as the later-state data is greater than the number of images recorded as the initial-state data.
6. A method in accordance with claim 1, wherein the initial-state data includes one or more components selected from a list including the time when the message display was initiated, the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and the later-state data includes one or more components selected from a list including the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and wherein the method further includes the step of comparing components of the initial-state data with equivalent component of the later-state data.
7. A method in accordance with claim 6, including the steps of performing a first comparison of an initial-state component with an equivalent later-state component, and if a screen shot image is detected then performing one or more check comparisons between the other initial-state components and later-state components, and indicating that a screen shot image has been captured if the check or checks performed determine that a screen shot image is present in the image memory after the message is displayed.
8. A method in accordance with any preceding claim, wherein the method includes the step of recording the later-state data when a message or messages are no longer displayed on the screen and/or periodically while a message or messages are displayed on the screen.
9. A method in accordance with any one of claims 1 to 7, wherein the method includes the step of recording the later-state data periodically while a message or messages are displayed on the screen and performing comparisons with the initial-state data to detect a screen shot image of the screen while a message or messages are displayed.
10. A method in accordance with any preceding claim, wherein the electronic device is capable of running multiple software applications, such that at any one time the screen may display an image produced by the software running in the foreground, and wherein the method includes the step of recording later-state data if the messaging software is put into thebackground.
11. A method in accordance with any preceding claim, including the step of exiting the messaging software when it is indicated that an image of the screen has been captured while the message was being displayed on the screen.
12. A method in accordance with any preceding claim, comprising the further steps of receiving a message which includes primary message content and secondary message content, wherein the secondary message content includes data representing a secondary image and a timing instruction, displaying the primary message content on the screen of the electronic device, superimposing the secondary image over the primary message content for a duration determined by the timing instruction.
13. A method in accordance with claim 12, wherein the timing instruction includes a duration for displaying the secondary image.
14. A method in accordance with claim 12 or claim 13, wherein the timing instruction includes a secondary image display repeat value, for determining if and when to repeat the display of the secondary image.
15. A method in accordance with any one of claims 12 to 14, comprising the step of reading a primary message view time, for determining how long to display the primary message for, displaying the primary message for the primary message view time and deleting the primary message from the memory of the electronic device after the primary message view time has expired.
16. A method in accordance with any one of claim 12 to 15, comprising the step of composing a message which includes primary message content for displaying on the screen of an electronic device, and secondary message content including a secondary image for obscuring the primary message content, said secondary message content further including timing instructions for determining the duration of display of the secondary image.
17. A method in accordance with any one of claims 12 to 16, comprising the step of providing a primary message view time for determining how long to display the primary message for.
18. A computer implemented messaging program for use with an electronic device connectable to a network of other electronic devices, said messaging program arranged to display messages received from other electronic devices on a screen of the electronic device, wherein said electronic device includes an image memory for storing images and meta data relating to the images, the meta data including a time-stamp indicating the time when the image was captured, said electronic device being further capable of capturing a screen shot of an image displayed on the screen and storing the screen shot image and meta data including a time-stamp in the image memory, wherein the messaging program includes a screen shot detector for detecting when a screen shot image has been captured, said screen shot detector comprising; a state recorder for recording initial-state data, said initial-state data representing the state of the electronic device when the display of messages is initiated, and later-state data representing the state of the electronic device after a message is displayed, a comparator for comparing the initial-state data with the later-state data and an indicator for indicating that a screen shot image has been captured based on the output of the comparator.
19. , the initial-state data is the time when the message display is initiated and the later-state data is the time-stamp of images stored in the image memory, and wherein the indicator is arranged to indicate that a screen shot image has been captured if the comparator determines that the time-stamp of an image stored in the image memory is later than the time when the message display was initiated.
20. Wherein the later-state data is the time-stamp of the last image to be stored in the image memory, and wherein the indicator is arranged to indicate that a screen shot image has been captured if the comparator determines that the time-stamp of the last image stored in the image memory is later than the time when the message display was initiated.
21. Wherein the initial-state data is the time-stamp of the last image to be stored in the image memory and the later-state data is also the time-stamp of the last image to be stored in the image memory, and wherein the indicator is arranged to indicate that a screen shot image has been captured if the comparator determines that the time-stamp recorded as the later-state data is later than the time-stamp recorded as the initial-state data.
22. Wherein the initial-state data is the number of images stored in the image memory and the later-state data is also the number of images stored in the image memory, and wherein the indicator is arranged to indicate that a screen shot image has been captured if the comparator determines that the number of images recorded as the later-state data is greater than the number of images recorded as the initial-state data.
23. Wherein the initial-state data includes one or more components selected from a list including the time when the message display was initiated, the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and the later-state data includes one or more components selected from a list including the time-stamp of images stored in the image memory, the time-stamp of the last image stored in the image memory and the number of images stored in the image memory, and wherein the comparator is arranged to compare components of the initial-state data with equivalent component of the later-state data.
24. Wherein the comparator is arranged to perform a first comparison of an initial-state component with an equivalent later-state component, and if a screen shot image is detected then the comparator is arranged to perform one or more check comparisons between the other initial-state components and later-state components, and the indicator is arranged to indicate that a screen shot image has been captured if the check or checks performed by the comparator determine that a screen shot image is present in the image memory after the message is displayed.
25. Wherein the state data recorder is arranged to record the later-state data when a message or messages are no longer displayed on the screen and/or periodically while a message or messages are displayed on the screen.
26. Wherein the state data recorder is arranged to record the later-state data periodically while a message or messages are displayed on the screen.