System and method for providing immersive visualization at low bandwidth rates

• US 20050060421A1
• Filed: 07/15/2004
• Published: 03/17/2005
• Est. Priority Date: 07/16/2003
• Status: Abandoned Application

• Current Assignee: IP Video Systems
• Original Assignee: IP Video Systems
• Inventors: Anand, Raghavan, Pirot, Johan, Musunuri, Chowdhary V., Kale, Rahul P.
• Application Number:
  US10/891,078
• Publication Number:
  US 20050060421A1
• Time in Patent Office: Days
• US Class Current: 709/231
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/762 at the source reformatting of additional data in video distribution servers H04N21/2355
• CPC Class Codes: H04N 19/107 between spatial and temporal predictive coding, e.g. picture refresh
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/174 the region being a slice, e.g. a line of blocks or a group of blocks
• CPC Class Codes: H04N 19/597 specially adapted for multi-view video sequence encoding
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

A system and method are disclosed for providing immersive visualization at low bandwidth rates. The system retrieves a frame of multimedia information for transmission over a network and converts the frame from a first color space to a second color space. The system slices the frame into a plurality of frame slices and transforms each of the plurality of frame slices into a plurality of corresponding frequency domain components. The system quantizes the frequency domain components of each frame slice, when the frame slice to be processed is an intra-slice or a refresh slice, to generate quantized frequency domain components of each frame slice. The system variable-length encodes the quantized frequency domain components of each frame slice to generate compressed multimedia information associated with each frame slice. The system constructs network packets of the compressed multimedia information associated with each frame slice, and transmits the network packets via the network.

Claims

1. A system for transmitting multimedia information via a network, comprising:

means for retrieving a frame of multimedia information for transmission over the network;

means for converting the frame from a first color space to a second color space,

wherein each component of the second color space is formed as a weighted combination of components of the first color space;

means for slicing the frame into a plurality of frame slices;

means for transforming each of the plurality of frame slices into a plurality of corresponding frequency domain components;

means for quantizing the frequency domain components of each frame slice when it is determined that each frame slice is to be processed as one of an intra-slice and a refresh slice to generate quantized frequency domain components of each frame slice;

means for variable-length encoding the quantized frequency domain components of each frame slice to generate compressed multimedia information associated with each frame slice;

means for constructing network packets of the compressed multimedia information associated with each frame slice; and

means for transmitting the network packets via the network.

2. The system of claim 1, wherein the means for retrieving comprises:

means for discarding a retrieved frame based on at least one of a size of a frame buffer for storing the retrieved frame and a rate at which frames are transmitted.

3. The system of claim 1, comprising:

means for discarding porches surrounding an active portion of the frame.

4. The system of claim 1, wherein the first color space comprises a red, green, blue (RGB) color space, and

wherein the second color space comprises a luminance and chrominance (YUV) color space.

5. The system of claim 4, comprising:

means for sub-sampling chrominance of the frame in a horizontal direction.

6. The system of claim 1, wherein each of the plurality of frame slices is transformed into the plurality of corresponding frequency domain components using a discrete cosine transform.

7. The system of claim 1, comprising:

means for subtracting the frequency domain components of each frame slice from frequency domain components of a corresponding frame slice associated with a previous frame to generate a frame difference.

8. The system of claim 7, comprising:

means for comparing the generated frame difference against predetermined noise filter threshold parameters to determine whether noise is associated with each frame slice.

9. The system of claim 8, comprising:

means for canceling a noise contribution from the frame difference, to determine whether the frame slice is substantially identical to the corresponding frame slice associated with the previous frame.

10. The system of claim 1, comprising:

means for determining whether each frame slice is to be one of (i) discarded and (ii) transmitted as one of the intra-slice and the refresh slice.

11. The system of claim 10, wherein the means for determining comprises:

means for characterizing a feature within the frame as static when one of (i) the feature within the frame is substantially identical to a feature associated with a previous frame and (ii) movement of the feature within the frame is below a predetermined threshold;

means for detecting a change in status of the feature within the frame from static to moving; and

means for assigning all frame slices of the frame as refresh slices when the change in status is detected.

12. The system of claim 1, wherein the means for quantizing comprises:

means for modifying an amount of quantization based on available bandwidth for transmitting.

13. The system of claim 1, wherein the network packets comprise Ethernet packets.

14. The system of claim 1, wherein the means for transmitting comprises:

means for receiving network statistic information associated with transmission of the network packets; and

means for modifying a transmission rate of the network packets based on the received network statistic information.

15. A system for receiving multimedia information transmitted via a network, comprising:

means for extracting compressed multimedia information from network packets received via the network;

means for inverse variable length coding the extracted compressed multimedia information to generate quantized frequency domain components of frame slices of a frame of multimedia information;

means for inverse quantizing the quantized frequency domain components of the frame slices to generate frequency domain components of the frame slices;

means for inverse transforming the frequency domain components of the frames slices to generate a plurality of frame slices;

means for combining the plurality of frame slices to form the frame of multimedia information;

means for converting the frame from a first color space to a second color space,

wherein each component of the second color space is formed as a weighted combination of components of the first color space; and

means for displaying the converted frame.

16. The system of claim 15, wherein the means for combining comprises:

means for replacing missing frame slices of the plurality of frame slices using corresponding frame slices from a previous frame.

17. The system of claim 15, wherein frequency domain components of the frame slices are inverse transformed into the plurality of frame slices using an inverse discrete cosine transform.

18. The system of claim 15, wherein the first color space comprises a luminance and chrominance (YUV) color space, and

wherein the second color space comprises a red, green, blue (RGB) color space.

19. The system of claim 15, comprising:

means for adding porches surrounding an active portion of the frame.

20. A method of transmitting multimedia information via a network, comprising the steps of:

retrieving a frame of multimedia information for transmission over the network;

converting the frame from a first color space to a second color space,

wherein each component of the second color space is formed as a weighted combination of components of the first color space;

slicing the frame into a plurality of frame slices;

transforming each of the plurality of frame slices into a plurality of corresponding frequency domain components;

quantizing the frequency domain components of each frame slice when it is determined that each frame slice is to be processed as one of an intra-slice and a refresh slice to generate quantized frequency domain components of each frame slice;

variable-length encoding the quantized frequency domain components of each frame slice to generate compressed multimedia information associated with each frame slice;

constructing network packets of the compressed multimedia information associated with each frame slice; and

transmitting the network packets via the network.

21. The method of claim 20, wherein the step of retrieving comprises the step of:

discarding a retrieved frame based on at least one of a size of a frame buffer for storing the retrieved frame and a rate at which frames are transmitted.

22. The method of claim 20, comprising the step of:

discarding porches surrounding an active portion of the frame.

23. The method of claim 20, wherein the first color space comprises a red, green, blue (RGB) color space, and

wherein the second color space comprises a luminance and chrominance (YUV) color space.

24. The method of claim 23, comprising the step of:

sub-sampling chrominance of the frame in a horizontal direction.

25. The method of claim 20, wherein each of the plurality of frame slices is transformed into the plurality of corresponding frequency domain components using a discrete cosine transform.

26. The method of claim 20, comprising the step of:

subtracting the frequency domain components of each frame slice from frequency domain components of a corresponding frame slice associated with a previous frame to generate a frame difference.

27. The method of claim 26, comprising the step of:

comparing the generated frame difference against predetermined noise filter threshold parameters to determine whether noise is associated with each frame slice.

28. The method of claim 27, comprising the step of:

canceling a noise contribution from the frame difference, to determine whether the frame slice is substantially identical to the corresponding frame slice associated with the previous frame.

29. The method of claim 20, comprising the step of:

determining whether each frame slice is to be one of (i) discarded and (ii) transmitted as one of the intra-slice and the refresh slice.

30. The method of claim 29, wherein the step of determining comprises the steps of:

characterizing a feature within the frame as static when one of (i) the feature within the frame is substantially identical to a feature associated with a previous frame and (ii) movement of the feature within the frame is below a predetermined threshold;

detecting a change in status of the feature within the frame from static to moving; and

assigning all frame slices of the frame as refresh slices when the change in status is detected

31. The method of claim 20, wherein the step of quantizing comprises the step of:

modifying an amount of quantization based on available bandwidth for transmitting.

32. The method of claim 20, wherein the network packets comprise Ethernet packets.

33. The method of claim 20, wherein the step of transmitting comprises the steps of:

receiving network statistic information associated with transmission of the network packets; and

modifying a transmission rate of the network packets based on the received network statistic information.

34. A method of receiving multimedia information transmitted via a network, comprising the steps of:

extracting compressed multimedia information from network packets received via the network;

inverse variable length coding the extracted compressed multimedia information to generate quantized frequency domain components of frame slices of a frame of multimedia information;

inverse quantizing the quantized frequency domain components of the frame slices to generate frequency domain components of the frame slices;

inverse transforming the frequency domain components of the frames slices to generate a plurality of frame slices;

combining the plurality of frame slices to form the frame of multimedia information;

converting the frame from a first color space to a second color space,

wherein each component of the second color space is formed as a weighted combination of components of the first color space; and

displaying the converted frame on a display device.

35. The method of claim 34, wherein the step of combining comprises the step of:

replacing missing frame slices of the plurality of frame slices using corresponding frame slices from a previous frame.

36. The method of claim 34, wherein frequency domain components of the frame slices are inverse transformed into the plurality of frame slices using an inverse discrete cosine transform.

37. The method of claim 34, wherein the first color space comprises a luminance and chrominance (YUV) color space, and

wherein the second color space comprises a red, green, blue (RGB) color space.

38. The method of claim 34, comprising the step of:

adding porches surrounding an active portion of the frame.