| 摘要 |
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). |
