SYSTEM AND METHOD FOR DATA TRANSMISSION

• US 20090172177A1
• Filed: 12/19/2005
• Published: 07/02/2009
• Est. Priority Date: 12/20/2004
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Lu, Kuei-Chih
• Granted Patent: US 8,161,175 B2
• Time in Patent Office: Days
• US Class Current: 709/230
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/193 at the transport layer, e.g. TCP related
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/165 Combined use of TCP and UDP protocols; selection criteria therefor
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04N 19/37 with arrangements for assigning different transmission priorities to video input data or to video coded data
• CPC Class Codes: H04N 19/89 involving methods or arrangements for detection of transmission errors at the decoder

Abstract

A data transmission system includes a sending device and a receiving device. The sending device includes an image receiving unit that indicates the order of reception of the blocks using version numbers, a first database for storing the version numbers of the blocks, a transmitting unit which transmits the blocks to the receiving device using User Datagram Protocol, a determination module which determines whether a block requires resending, an updating unit for updating the version numbers in the first database, and a notification unit for notifying the receiving device of the latest version number of the block at each position using Transmission Control Protocol. The receiving device includes a second database, a receiving unit for receiving blocks using User Datagram Protocol, a display unit for determining the version numbers of the blocks and for displaying the blocks, and a processing unit for sending a request to the sending device.

Claims

1. A sending device for transmitting data to a receiving end, said sending device comprising:

an image receiving unit which divides each image received thereby into a plurality of blocks, and which indicates order of reception of blocks received by said image receiving unit using different version numbers;

a first database for storing image data and the version number of a latest block at each position in the image received by said image receiving unit;

a transmitting unit connected electrically to said image receiving unit, said transmitting unit transmitting the image data of a block received thereby, a corresponding position of the block in the image, and the version number of the block to the receiving end;

a determination module connected electrically to said image receiving unit and disposed to receive a block transmitted from said image receiving unit, said determination module issuing a notification upon determining that the block needs to be transmitted to the receiving end;

an updating unit connected electrically to said first database, said determination module, and said transmitting unit, and disposed to receive the notification transmitted from said determination module, said updating unit updating the version number in said first database according to the notification and transmitting the updated version number, the image data of the block, and the position of the block in the image to said transmitting unit; and

a notification unit connected electrically to said first database, said notification unit referring to the latest version numbers stored in said first database every inspection cycle, and using Transmission Control Protocol to send a notification to the receiving end so as to notify the receiving end of the latest version number of the block at each position in an image.

2. The sending device as claimed in claim 1, wherein said determination modules includes a comparison unit connected electrically to said updating unit, said comparison unit comparing image data of the blocks which are at the same position such that when the image data of a block have changed, said comparison unit sends a notification including the block and the current version number of the block to said updating unit.

3. The sending device as claimed in claim 1, wherein said image receiving unit assigns a flag to each block, each flag being set to a first state or a second state such that when the flag is in the first state, this indicates that the block corresponding to the flag needs to be resent to the receiving end, said flag being set to the second state when the block corresponding to the flag has been resent or the block corresponding to the flag does not need to be resent to the receiving end, the state of the flag of the latest block at each position in the image being stored in said first database.

4. The sending device as claimed in claim 3, wherein said updating unit is capable of switching the flag of the block that has been transmitted to the receiving end and that is stored in said first database to the second state.

5. The sending device as claimed in claim 3, further comprising a command receiving unit connected electrically to said first database, said command receiving unit utilizing Transmission Control Protocol to receive a command to resend a block from the receiving end and controlling the states of the flags stored in said first database according to the command such that when said command includes a block that the receiving end wants said sending device to resend, said command receiving unit sets the state of the flag corresponding to said block to the first state.

6. The sending device as claimed in claim 5, wherein said determination module includes a detection unit connected electrically to said updating unit and said first database, said detection unit detecting the states of the flags stored in said first database and, upon detecting one of the flags to be in the first state, notifying said updating unit of the block to which said one of the flags corresponds and the current version number of the block.

7. The sending device as claimed in claim 1, wherein said image receiving unit can continuously receive images from a video camera.

8. The sending device as claimed in claim 1, wherein said image receiving unit can continuously capture screen frames.

9. The sending device as claimed in claim 1, wherein said image receiving unit notifies said notification unit that an inspection cycle has been reached every time K images are received, K being an integer greater than or equal to 1.

10. A receiving device for receiving data sent from a sending end, said receiving device comprising:

a second database for storing version numbers of a plurality of blocks;

a data receiving unit which utilizes User Datagram Protocol to receive image data of the blocks, the version numbers of the blocks, and the positions of the blocks in an image sent from the sending end;

a display unit connected electrically to said second database and said data receiving unit, said display unit receiving a block transmitted from said data receiving unit and comparing the version number of the block with the version number stored in said second database such that, when the version number of the block is newer, the version number stored in said second database is updated, and the block with the newer version number is displayed on a display screen; and

a processing unit connected electrically to said second database, said processing unit comparing the latest version numbers of the blocks stored in said second database with the latest version number of the sent block as notified by the sending end such that, when it is found that the version number recorded in said second database is older than the latest version number as notified by the sending end, said processing unit issues a request to the sending end using Transmission Control Protocol to demand resending of the block.

11. A data transmission system including a sending device and a receiving device, said sending device being capable of transmitting data to said receiving device, said receiving device being capable of receiving the data sent from said sending device,

said sending device comprising:

an image receiving unit which divides each image received thereby into a plurality of blocks, and which indicates order of reception of blocks received by said image receiving unit using different version numbers;

a first database for storing image data and the version number of a latest block at each position in the image received by said image receiving unit;

a transmitting unit connected electrically to said image receiving unit, said transmitting unit transmitting the image data of a block received thereby, a corresponding position of the block in the image, and the version number of the block to said receiving device;

a determination module connected electrically to said image receiving unit and disposed to receive a block transmitted from said image receiving unit, said determination module issuing a notification upon determining that the block needs to be transmitted to said receiving device;

an updating unit connected electrically to said first database, said determination module, and said transmitting unit, and disposed to receive the notification transmitted from said determination module, said updating unit updating the version number in said first database according to the notification and transmitting the updated version number, the image data of the block, and the position of the block in the image to said transmitting unit; and

a notification unit connected electrically to said first database, said notification unit referring to the latest version numbers stored in said first database every inspection cycle, and using Transmission Control Protocol to send a notification to said receiving device so as to notify said receiving device of the latest version number of the block at each position in an image;

said receiving device comprising;

a second database for storing version numbers of a plurality of blocks;

a data receiving unit which utilizes User Datagram Protocol to receive the image data of the blocks, the version numbers of the blocks, and the positions of the blocks in an image sent from said sending device;

a display unit connected electrically to said second database and said data receiving unit, said display unit receiving a block transmitted from said data receiving unit and comparing the version number of the block with the version number stored in said second database such that, when the version number of the block is newer, the version number stored in said second database is updated, and the block with the newer version number is displayed on a display screen; and

a processing unit connected electrically to said second database, said processing unit comparing the latest version numbers of the blocks stored in said second database with the latest version number of the sent block as notified by said sending device such that, when it is found that the version number recorded in said second database is older than the latest version number as notified by said sending device, said processing unit issues a request to said sending device using Transmission Control Protocol to demand resending of the block.

12. The data transmission system as claimed in claim 11, wherein said determination modules includes a comparison unit connected electrically to said updating unit, said comparison unit comparing image data of blocks which are at the same position such that when the image data of a block have changed, said comparison unit sends a notification including the block and the current version number of the block to said updating unit.

13. The data transmission system as claimed in claim 11, wherein said image receiving unit assigns a flag to each block, each flag being set to a first state or a second state such that when the flag is in the first state, this indicates that the block corresponding to the flag needs to be resent to said receiving device, said flag being set to the second state when the block corresponding to the flag has been resent or the block corresponding to the flag does not need to be resent to said receiving device, the state of the flag of the latest block at each position in the image being stored in said first database.

14. The data transmission system as claimed in claim 13, wherein said updating unit is capable of switching the flag of the block that has been transmitted to said receiving device and that is stored in said first database to the second state.

15. The data transmission system as claimed in claim 13, wherein said sending device further comprises a command receiving unit connected electrically to said first database, said command receiving unit utilizing Transmission Control Protocol to receive a command to resend a block from said receiving device and controlling the states of the flags stored in said first database according to the command such that when said command includes a block that said receiving device wants said sending device to resend, said command receiving unit sets the state of the flag corresponding to said block to the first state.

16. The data transmission system as claimed in claim 15, wherein said determination module includes a detection unit connected electrically to said updating unit and said first database, said detection unit detecting the states of the flags stored in said first database and, upon detecting one of the flags to be in the first state, notifying said updating unit of the block to which said one of the flags corresponds and the current version number of the block.

17. The data transmission system as claimed in claim 11, wherein said image receiving unit can continuously receive images from a video camera.

18. The data transmission system as claimed in claim 11, wherein said image receiving unit can continuously capture screen frames.

19. The data transmission system as claimed in claim 11, wherein said image receiving unit notifies said notification unit that an inspection cycle has been reached every time K images are received, K being an integer greater than or equal to 1.

20. A data transmitting method for transmitting data from a sending end to a receiving end, the data transmitting method comprising the following steps:

(A) receiving a first image and dividing the image into N blocks, N being a positive integer greater than or equal to 1, giving each block a corresponding initial version number, and storing image data and the initial version number of each block into a first database;

(B) using User Datagram Protocol to send each block in step (A) to the receiving end;

(C) receiving a next image and dividing the image into N blocks;

(D) determining whether one of the plurality of blocks in step (C) requires resending, the flow proceeding to step (E) if said block does not require resending, the flow otherwise skipping to step (H) to carry out steps (H) and (I) in turn if said block requires resending;

(E) determining whether all of the blocks in an entire image have been processed, the flow proceeding to step (F) if all the blocks have been processed, the flow returning to step (D) to continue processing of other blocks if otherwise;

(F) determining whether K images have been processed, the flow proceeding to step (G) if K images have been processed, the flow returning to step (C) if otherwise, K being a positive integer greater than or equal to 1;

(G) using Transmission Control Protocol to issue a notification to the receiving end to notify the receiving end of a latest version number of each block at each position in an image;

(H) updating the version number of the block stored in the first database which requires resending, and storing the image data of the block requiring resending into the first database; and

(I) using User Datagram Protocol to transmit the image data and the version number of the block requiring resending, and the position of the block requiring resending in the image to the receiving end, the flow returning to step (E) thereafter.

21. The data transmitting method as claimed in claim 20, wherein, in step (A), each block is further given a corresponding flag, each flag being set to be in a first state or a second state, the flag indicating that a block corresponding to the flag requires resending to the receiving end when the flag is in the first state, the flag being set to the second state when the block corresponding to the flag has been resent or does not require resending to the receiving end, the state of the flag of the latest block at each position in the image being stored in the first database.

22. The data transmitting method as claimed in claim 21, further comprising a step of setting the flags in the first database to the second state between steps (A) and (C).

23. The data transmitting method as claimed in claim 22, wherein, in step (D), resending of the block is determined according to the state of the corresponding flag in the first database.

24. The data transmitting method as claimed in claim 23, further comprising a step of comparing the image data of a received block with that of the block at the same position in an immediately preceding image between steps (D) and (E), the flow proceeding to step (E) if the image data are the same, the flow proceeding to step (H) to carry out steps (H) and (I) in turn if otherwise.

25. The data transmitting method as claimed in claim 23, further comprising a step of receiving a command sent from the receiving end using Transmission Control Protocol, and a step of controlling the states of the flags stored in the first database according to the received command so as to place the flag of the block requiring resending in the first state.

26. A data receiving method for receiving data transmitted from a sending end, the data receiving method comprising the following steps:

(a) using User Datagram Protocol to receive a block, a version number of the block, and position of the block in an image from a sending end;

(b) determining whether the version number of the block is the earliest version number of blocks at the same position received in step (a), and displaying directly the block on a display screen and storing the version number of the block in a second database when the received block is the block with the earliest version number,

when not the block with the earliest version number, the version number of the block being compared with the version number of a corresponding block stored in the second database, the version number of the corresponding block stored in the second database being updated when the version number of the block is newer than the version number of the corresponding block stored in the second database, the block having the newer version number being displayed on the display screen;

(c) receiving a notification of the latest version number of the block at each position from the sending end through Transmission Control Protocol; and

(d) comparing the version number recorded in the second database with the version number sent from the sending end and, when the version number recorded in the second database is older, requesting the sending end to send the block with the newer version number through Transmission Control Protocol.

27. A data transmission method, which includes a data transmitting method and a data receiving method, the data transmitting method being used to send data from a sending end to a receiving end, the data receiving method being used to receive the data transmitted from the sending end,

the data transmitting method comprising the following steps:

(A) receiving a first image and dividing the image into N blocks, N being a positive integer greater than or equal to 1, giving each block a corresponding initial version number, and storing image data and the initial version number of each block into a first database;

(B) using User Datagram Protocol to send each block in step (A) to the receiving end;

(C) receiving a next image and dividing the image into N blocks;

(D) determining whether one of the plurality of blocks in step (C) requires resending, the flow proceeding to step (E) if said block does not require resending, the flow otherwise skipping to step (H) to carry out steps (H) and (I) in turn if said block requires resending;

(E) determining whether all of the blocks in an entire image have been processed, the flow proceeding to step (F) if all the blocks have been processed, the flow returning to step (D) to continue processing of other blocks if otherwise;

(F) determining whether K images have been processed, the flow proceeding to step (G) if K images have been processed, the flow returning to step (C) if otherwise, K being a positive integer greater than or equal to 1;

(G) using Transmission Control Protocol to issue a notification to the receiving end to notify the receiving end of a latest version number of each block at each position in an image;

(H) updating the version number of the block stored in the first database which requires resending, and storing the image data of the block requiring resending into the first database; and

(I) using User Datagram Protocol to transmit the image data and the version number of the block requiring resending, and the position of the block requiring resending in the image to the receiving end, the flow returning to step (E) thereafter;

the data receiving method comprising the following steps;

(a) using User Datagram Protocol to receive a block, a version number of the block, and position of the block in an image from the sending end;

(b) determining whether the version number of the block is the earliest version number of blocks at the same position received in step (a), and displaying directly the block on a display screen and storing the version number of the block in a second database when the received block is the block with the earliest version number,

when not the block with the earliest version number, the version number of the block being compared with the version number of a corresponding block stored in the second database, the version number of the corresponding block stored in the second database being updated when the version number of the block is newer than the version number of the corresponding block stored in the second database, the block having the newer version number being displayed on the display screen;

(c) receiving a notification of the latest version number of the block at each position from the sending end through Transmission Control Protocol; and

(d) comparing the version number recorded in the second database with the version number sent from the sending end and, when the version number recorded in the second database is older, requesting the sending end to send the block with the newer version number through Transmission Control Protocol.

28. The data transmission method as claimed in claim 27, wherein, in step (A), each block is further given a corresponding flag, each flag being set to be in a first state or a second state, the flag indicating that a block corresponding to the flag requires resending to the receiving end when the flag is in the first state, the flag being set to the second state when the block corresponding to the flag has been resent or does not require resending to the receiving end, the state of the flag of the latest block at each position in the image being stored in the first database.

29. The data transmission method as claimed in claim 28, wherein the data transmitting method further includes a step of setting the flags in the first database to the second state between steps (A) and (C).

30. The data transmission method as claimed in claim 29, wherein, in step (D), resending of the block is determined according to the state of the corresponding flag in the first database.

31. The data transmission method as claimed in claim 30, wherein the data transmitting method further includes a step of comparing the image data of a received block with that of the block at the same position in an immediately preceding image between steps (D) and (E), the flow proceeding to step (E) if the image data are the same, the flow proceeding to step (H) to carry out steps (H) and (I) in turn if otherwise.

32. The data transmission method as claimed in claim 30, wherein the data transmitting method further includes a step of receiving a command sent from the receiving end using Transmission Control Protocol, and a step of controlling the states of the flags stored in the first database according to the received command so as to place the flag of the block requiring resending in the first state.