1. An interactive projection apparatus, comprising a projection unit, a photosensitive unit and a control unit, wherein the projection unit projects a positioning beam onto a surface to form a positioning pattern, the photosensitive unit has a sensing area, the photosensitive unit senses the positioning pattern in the sensing area, and the control unit is coupled to the projection unit and the photosensitive unit, calculates a coordinate information of the positioning pattern and defines an effective touch area according to the coordinate information of the positioning pattern, wherein when the photosensitive unit senses a light spot in the sensing area, the control unit decides whether or not the light spot is located in the effective touch area, if the light spot is located in the effective touch area, the position of the light spot serves as a touch position of an input tool; if the light spot is not located in the effective touch area, the light spot is ignored.
2. The interactive projection apparatus as claimed in claim 1, wherein the photosensitive unit comprises a visible-light mode and an invisible-light mode, and when the photosensitive unit is in the invisible-light mode, it senses the light spot at the sensing area.
3. The interactive projection apparatus as claimed in claim 2, wherein when the photosensitive unit is in the visible-light mode, the control unit further controls the projection unit according to an adjustment instruction to adjust the projected positioning pattern and to calculate the coordinate information of the positioning pattern so as to change the effective touch area defined by the coordinate information of the positioning pattern.
4. The interactive projection apparatus as claimed in claim 2, wherein the photosensitive unit further senses a plurality of positioning light spots on a plurality of position marks indicated by the positioning pattern, the control unit calculates the coordinate information of the positioning pattern according to the positioning light spots and defines the effective touch area, wherein the photosensitive unit is in the invisible-light mode and the positioning light spots are invisible-light.
5. The interactive projection apparatus as claimed in claim 1, wherein the positioning pattern comprises four dots, and the four dots define the effective touch area of a rectangle.
6. The interactive projection apparatus as claimed in claim 1, wherein the positioning pattern comprises a plurality of segments and the segments define the effective touch area of a rectangle.
7. The interactive projection apparatus as claimed in claim 1, wherein the surface is a projection screen or an electronic whiteboard.
8. A touch position determining method of an interactive projection apparatus, comprising:
projecting a positioning beam onto a surface and forming a positioning pattern at the surface;
sensing the positioning pattern in a sensing area;
calculating coordinate information of the positioning pattern;
defining an effective touch area according to the coordinate information of the positioning pattern;
sensing a light spot in the sensing area;
judging whether or not the light spot is located in the effective touch area;
if the light spot is located in the effective touch area, taking a position of the light spot as a touch position of an input tool; and
if the light spot is not located in the effective touch area, ignoring the light spot.
9. The touch position determining method of an interactive projection apparatus as claimed in claim 8, further comprising:
switching to a visible-light mode;
judging whether or not receiving an adjustment instruction; and
if receiving the adjustment instruction, adjusting the projected positioning pattern according to the adjustment instruction and calculating the coordinate information of the positioning pattern so as to change the effective touch area defined by the coordinate information of the positioning pattern.
10. The touch position determining method of an interactive projection apparatus as claimed in claim 8, wherein the step of defining the effective touch area according to the coordinate information of the positioning pattern further comprises:
switching to an invisible-light mode;
sensing a plurality of positioning light spots on a plurality of position marks indicated by the positioning pattern; and
calculating the coordinate information of the positioning pattern according to the positioning light spots and defining the effective touch area, wherein the positioning light spots are invisible light.
11. The touch position determining method of an interactive projection apparatus as claimed in claim 8, wherein the positioning pattern comprises four dots, and the four dots define the effective touch area of a rectangle.
12. The touch position determining method of an interactive projection apparatus as claimed in claim 8, wherein the positioning pattern comprises a plurality of segments and the segments define the effective touch area of a rectangle.
13. The touch position determining method of an interactive projection apparatus as claimed in claim 8, wherein the surface is a projection screen or an electronic whiteboard.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A communications network comprising:
an originating Real Time Data over IP host;
a terminating Real Time Data over IP host;
communication control means for at least receiving information relating to a communication;
a first communication forwarding means that replaces a fixed IP address in a data packet sent from the terminating Real Time Data over IP host to the originating Real Time Data over IP host with a first dynamic IP address to conceal the fixed IP address of the terminating Real Time Data over IP host, wherein the fixed IP address of the originating Real Time Data over IP host is unknown to the first communication forwarding means; and
a second communication forwarding means that replaces a fixed IP address in a data packet from the originating Real Time Data over IP host to the terminating Real Time Data over IP host with a second dynamic IP address to conceal the fixed IP address of the originating Real Time Data over IP host, wherein the fixed IP address of the terminating Real Time Data over IP host is unknown to the second communication forwarding means,
wherein, during the setup of a communication session between the originating Real Time Data over IP host and the terminating Real Time Data over IP host, the communication control means exchanges only the dynamic IP addresses between the first and second communications forwarding means.
2. The network according to claim 1, wherein at least part of the network between one of the communication forwarding means and one of the Real Time Data over IP hosts is a Real Time Data over IP network.
3. The network according to claim 2, further comprising a plurality of communication forwarding means, wherein each of the Real Time Data over IP hosts is connected to a selected one of the communication forwarding means.
4. The network according to claim 1, wherein at least one of the communication forwarding means comprises a translation means that translates an external reference of one or both of the hosts into an internal reference.
5. The network according to claim 1, wherein at least one of the communication forwarding means further comprises tracking means for measuring at least one predefined parameter related to the communication and the communication forwarding means comprises transmitting means for transmitting the measured value to a selected data receiver.
6. The network according to claim 1, wherein at least one of the Real Time Data over IP hosts comprises message means for transmitting a message to the communication control means to indicate that a communication session is in progress.
7. A method of controlling communication on a communications network comprising an originating Real Time Data over IP host and a terminating Real Time Data over IP host between which communication is to be effected and a communication control means for receiving information relating to the communication, wherein the method comprises:
transmitting at least some data from the originating Real Time Data over IP host to a first communication forwarding means, wherein the first communication forwarding means replaces a fixed IP address in a data packet sent from the originating Real Time Data over IP host to the terminating Real Time Data over IP host with a first dynamic IP address to conceal the fixed IP address of the originating Real Time Data over IP host, and wherein the fixed IP address of the terminating Real Time Data over IP host is unknown to the first communication forwarding means;
transmitting at least some data from the terminating Real Time Data over IP host to a second communication forwarding means, wherein the second communication forwarding means replaces a fixed IP address in a data packet sent from the terminating Real Time Data over IP host to the originating Real Time Data over IP host with a second dynamic IP address to conceal the fixed IP address of the terminating Real Time Data over IP host, and wherein the fixed IP address of the originating Real Time Data over IP host is unknown to the second communication forwarding means;
using the communication forwarding means to direct communication between the Real Time Data over IP hosts; and
sending information relating to the communication from the communication forwarding means to the communication control means,
wherein, during the setup of a communication session between the originating Real Time Data over IP host and the terminating Real Time Data over IP host, the communication control means exchanges only the dynamic IP addresses between the first and second communications forwarding means.
8. A communications network comprising:
an originating Real Time Data over IP host;
a terminating Real Time Data over IP host;
a communications controller for at least receiving information relating to a communication;
a first gateway that replaces a fixed IP address in a data packet sent from the terminating Real Time Data over IP host to the originating Real Time Data over IP host with a first dynamic IP address to conceal the fixed IP address of the terminating Real Time Data over IP host, wherein the fixed IP address of the originating Real Time Data over IP host is unknown to the first gateway; and
a second gateway that replaces a fixed IP address in a data packet from the originating Real Time Data to the terminating Real Time Data over IP host with a second dynamic IP address to conceal a fixed IP address of the originating Real Time Data over IP host, wherein the fixed IP address of the terminating Real Time Data over IP host is unknown to the second gateway,
wherein, during the setup of a communication session between the originating Real Time Data over IP host and the terminating Real Time Data over IP host, the communication controller exchanges only the dynamic IP addresses between the first and second gateways.
9. The network according to claim 8, wherein at least part of the network between one of the gateways and one of the Real Time Data over IP hosts is a Real Time Data over IP network.
10. The network according to claim 9, further comprising a plurality of gateways, wherein each of the Real Time Data over IP hosts is connected to a selected one of the gateways.
11. The network according to claim 8, wherein at least one of the gateways comprises a translator that translates an external reference of one or both of the hosts into an internal reference.
12. The network according to claim 8, wherein at least one of the gateways further comprises a tracker for measuring at least one predefined parameter related to the communication and the gateway comprises a transmitter for transmitting the measured value to a selected data receiver.
13. The network according to claim 8, wherein at least one of the Real Time Data over IP hosts comprises a message transmitter for transmitting a message to the communications controller to indicate that a communication session is in progress.
14. The network according to claim 1, wherein the first and second communication forwarding means each comprise a translation means for translating a fixed IP address of a Real Time Data over IP host into a dynamic IP address.
15. The network according to claim 8, wherein the first and second gateways each comprise a translator for translating a fixed IP address of a Real Time Data over IP host into a dynamic IP address.