System and Method for Securely Transmitting Video Over a Network

• US 20090168892A1
• Filed: 12/28/2007
• Published: 07/02/2009
• Est. Priority Date: 12/28/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: McFarland, Rowan L., Tighe, James Rodgers
• Granted Patent: US 8,837,598 B2
• Time in Patent Office: Days
• US Class Current: 375/240.240
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/44055 by partially decrypting, e.g. decrypting a video stream that has been partially encrypted
• CPC Class Codes: H04N 21/63345 by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

A method comprises receiving a bit stream associated with at least one video image, wherein the bit stream comprises at least one macroblock header and a plurality of macroblocks. The method continues by encrypting the at least one macroblock header. The method concludes by transmitting the bit stream such that the at least one macroblock header is in an encrypted format and at least one macroblock is in an unencrypted format.

Claims

1. A method, comprising:

receiving a bit stream associated with at least one video image, wherein the bit stream comprises at least one macroblock header and a plurality of macroblocks;

encrypting the at least one macroblock header; and

transmitting the bit stream such that;

the at least one macroblock header is in an encrypted format; and

at least one macroblock is in an unencrypted format.

2. The method of claim 1, wherein the bit stream associated with the at least one video image is encoded according to at least one of the following formats:

H.261, H.263, H.264, MPEG-1, MPEG-2, and MPEG-4.

3. The method of claim 1, wherein the macroblock header maps each macroblock to a respective portion of the video image.

4. The method of claim 1, wherein:

the at least one video image comprises a plurality of pixels; and

each macroblock is associated with a respective portion of the plurality of pixels.

5. The method of claim 1, wherein:

each macroblock in the received bit stream comprises chrominance data in a particular digital format;

the at least one macroblock header is encrypted while the chrominance data in the plurality of macroblocks remains in the particular digital format; and

transmitting the bit stream such that the at least one macroblock is in an unencrypted format comprises transmitting the plurality of macroblocks in the particular digital format.

6. The method of claim 1, wherein:

the plurality of macroblocks in the received bit stream are arranged in a first sequence;

and further comprising;

in conjunction with encrypting the at least one macroblock header, rearranging the plurality of macroblocks into a second sequence in the bit stream.

7. The method of claim 6, wherein:

the second sequence is a pseudo-random sequence based at least in part on a scramble key; and

rearranging the plurality of macroblocks into the second sequence comprises ordering the plurality of macroblocks in the bit stream in accordance with the second sequence.

8. The method of claim 1, wherein:

the bit stream is transmitted over a network to a decrypter;

and further comprising;

decrypting the at least one macroblock header;

decompressing the bit stream associated with the at least one video image; and

displaying the at least one video image.

9. An apparatus, comprising:

a memory operable to store a cryptographic key; and

a processor communicatively coupled to the memory and operable to;

receive a bit stream associated with at least one video image, wherein the bit stream comprises at least one macroblock header and a plurality of macroblocks;

encrypt the at least one macroblock header based at least in part on the cryptographic key; and

transmit the bit stream such that;

the at least one macroblock header is in an encrypted format; and

at least one macroblock is in an unencrypted format.

10. The apparatus of claim 9, wherein the bit stream associated with the at least one video image is encoded according to at least one of the following formats:

H.261, H.263, H.264, MPEG-1, MPEG-2, and MPEG-4.

11. The apparatus of claim 9, wherein the macroblock header maps each macroblock to a respective portion of the video image.

12. The apparatus of claim 9, wherein:

the at least one video image comprises a plurality of pixels; and

each macroblock is associated with a respective portion of the plurality of pixels.

13. The apparatus of claim 9, wherein:

each macroblock in the received bit stream comprises chrominance data in a particular digital format;

the at least one macroblock header is encrypted while the chrominance data in the plurality of macroblocks remains in the particular digital format; and

transmitting the bit stream such that the at least one macroblock is in an unencrypted format comprises transmitting the plurality of macroblocks in the particular digital format.

14. The apparatus of claim 9, wherein:

the plurality of macroblocks in the received bit stream are arranged in a first sequence; and

in conjunction with encrypting the at least one macroblock header, the processor is further operable to rearrange the plurality of macroblocks into a second sequence in the bit stream.

15. The apparatus of claim 14, wherein:

the second sequence is a pseudo-random sequence based at least in part on a scramble key; and

rearranging the plurality of macroblocks into the second sequence comprises ordering the plurality of macroblocks in the bit stream in accordance with the second sequence.

16. The apparatus of claim 15, wherein the processor is further operable to:

encrypt the scramble key; and

in conjunction with transmitting the bit stream, transmit the encrypted scramble key.

17. A system, comprising:

a camera operable to capture at least one video image;

an encoder communicatively coupled to the camera, wherein;

the encoder is operable to compress the at least one video image into a bit stream; and

the bit stream comprises at least one macroblock header and a plurality of macroblocks;

and

an encrypter communicatively coupled to the encoder and operable to;

encrypt the at least one macroblock header; and

transmit the bit stream such that;

the at least one macroblock header is in an encrypted format; and

at least one macroblock is in an unencrypted format.

18. The system of claim 17, wherein the macroblock header maps each macroblock to a respective portion of the video image.

19. The system of claim 17, wherein:

each macroblock in the received bit stream comprises chrominance data in a particular digital format;

the at least one macroblock header is encrypted while the chrominance data in the plurality of macroblocks remains in the particular digital format; and

transmitting the bit stream such that the at least one macroblock is in an unencrypted format comprises transmitting the plurality of macroblocks in the particular digital format.

20. The system of claim 17, wherein:

the bit stream is transmitted over a network to a decrypter that is operable to decrypt the at least one macroblock header;

and further comprising;

a decoder that is operable to decompress the bit stream, wherein decompressing the bit stream comprises mapping at least one macroblock to a portion of the at least one video image based at least in part on the decrypted macroblock header.