Method for measuring multimedia video communication quality

1. A method for measuring multimedia video communication quality, comprising:

uniformly dividing the multimedia video data frames into blocks of equal size;

embedding an equal amount of the original watermark data in a part of the blocks or all of the blocks at a transmitting side;

transmitting the multimedia video data to a receiving side;

extracting a recovered watermark from the received multimedia video data at the receiving side; and

calculating a distortion degree of the recovered watermark relative to the original watermark,

wherein uniformly dividing the multimedia video data frames into blocks of equal size, and embedding an equal amount of the original watermark data in a part of the blocks or all of the blocks at a transmitting side comprises: dividing the multimedia video data into groups at the transmitting side, each group comprising an equal number of frames, and selecting at least two frames with an equal interval in a same group as embedded frames, uniformly dividing each of the embedded frame into a plurality of blocks of equal size, selecting an equal number of blocks from the plurality of blocks as embedded blocks, and embedding an equal amount of the original watermark data in each of the embedded blocks.

2. The method of claim 1 , further comprising: performing compression coding or data packaging or framing at the transmitting side, and transmitting the data to the receiving side.

3. A method for measuring multimedia video communication quality, comprising:

uniformly dividing the multimedia video data frames into blocks of equal size;

embedding an equal amount of the original watermark data in a part of the blocks or all of the blocks at a transmitting side;

transmitting the multimedia video data to a receiving side;

extracting a recovered watermark from the received multimedia video data at the receiving side; and

calculating a distortion degree of the recovered watermark relative to the original watermark,

wherein each multimedia video data frame comprises M rows×N columns pixels in which the M rows are numbered from 0 to M−1 and the N columns are numbered from 0 to N−1, and uniformly dividing a multimedia video data frame into blocks of equal size comprises:

dividing each multimedia video data frame into m strips numbered from 0 to m−1, the strip i(i=0, 1, . . . , m−2) comprising pixels from row i×k v to row (i+1)×K v −1, and the strip m−1 comprising pixels from row (m−1)×k v to row M−1, wherein m is a minimum integer greater than or equal to M/k v ; if m=M/K v , the strip m−1 comprising zero row of pixels;

dividing the strip i(i=0, 1, . . . , m−1) into n blocks numbered from i×n to (i+1)×n−1, the block i×n+j(0, 1, . . . ,n−2) comprising pixels from column j×k h to column (j+1)×k h −1 of this strip, and the block n−1 comprising pixels from column (n−1)×k h to column N−1, wherein n is a minimum integer greater than or equal to N/k h ; if n=N/k h , the strip n−1 comprising zero column of pixels; and

embedding an equal amount of the original watermark data in each of the obtained m×n blocks.

4. The method of claim 1 , wherein each frame of the multimedia video data is uniformly divided into L blocks numbered from 0 to L−1, and the embedding the original watermark further comprises:

dividing a frame sequence into groups, each group comprising P×Q frames, which sequentially are frame 0 to frame P×Q−1 of the group;

selecting a frame q×P(q=0, . . . ,Q−1) of each group as the embedded frame;

selecting a block q+r×Q(r=0, . . . ,R−1,and q+r×Q≦L) of the embedded frame q×P(q=0, . . . ,Q−1) as the embedded block, wherein R is a maximum integer less than or equal to L/Q ; and

embedding an equal amount of the original watermark data in all the embedded blocks of the group.

5. A method for measuring multimedia video communication quality, comprising:

uniformly dividing the multimedia video data frames into blocks of equal size;

embedding an equal amount of the original watermark data in a part of the blocks or all of the blocks at a transmitting side;

transmitting the multimedia video data to a receiving side;

extracting a recovered watermark from the received multimedia video data at the receiving side;

calculating a distortion degree of the recovered watermark relative to the original watermark; and

determining a bit number of the original watermark data embedded in a part of the blocks or all of the blocks according to the size of the data block,

wherein embedding 1-bit data of the original watermark in the multimedia video data block comprises:

calculating an average value μ of the multimedia video data block according to pixels;

modifying a value of each pixel in the multimedia video data block according to b′=b+c , wherein b′ is a modified value of a pixel, b is a value of the pixel before modification, and c is a modification amount,

wherein the modification amount is calculated according to the following formula:

when the original watermark data bit is 1,

c

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when the original watermark data bit is 0,

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 and

wherein γ is a remainder of μ being divided by 2A , A represents an embedding strength and is equal to 2×Q P −1, and Q P represents a quantization factor for the multimedia video communication compression coding.

6. A method for measuring multimedia video communication quality, comprising:

uniformly dividing the multimedia video data frames into blocks of equal size;

embedding an equal amount of the original watermark data in a part of the blocks or all of the blocks at a transmitting side;

transmitting the multimedia video data to a receiving side;

extracting a recovered watermark from the received multimedia video data at the receiving side; and

calculating a distortion degree of the recovered watermark relative to the original watermark; and

determining a bit number of the original watermark data embedded in a part of the blocks or all of the blocks according to the size of the data block,

wherein extracting a data bit of the recovered watermark from the received multimedia video data block comprises:

calculating an average value μ′ of the received multimedia video data block according to pixels; and

calculating extracted data w′ of the recovered watermark according to the following formula:

w

′

=

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0

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 and

wherein γ′ is a remainder of μ′ being divided by 2A , A represents an embedding strength and is equal to 2×Q P− 1, and Q P represents a quantization factor for the multimedia video communication compression coding.

7. The method of claim 1 , further comprising: calculating a Peak Signal-to-Noise Ratio using a Pixel Recovery Rate of the recovered watermark relative to the original watermark to measure objective quality of the multimedia video communication.

8. The method of claim 7 , wherein the calculating a Peak Signal-to-Noise Ratio using a Pixel Recovery Rate of the recovered watermark relative to the original watermark to measure objected quality of the multimedia video communication comprises: fitting to obtain an estimated value of the Peak Signal-to-Noise Ratio using a linear function of the Pixel Recovery Rate of the recovered watermark relative to the original watermark based on statistic data of a multimedia video communication experiment and according to a Mean Square Error criterion to measure the objective quality of the multimedia video communication.

9. The method of claim 1 , wherein calculating the distortion degree of the recovered watermark relative to the original watermark measures the objective quality of the multimedia video communication.

10. The method of claim 9 , wherein the calculating the distortion degree of the recovered watermark relative to the original watermark comprises: calculating the distortion degree of the recovered watermark relative to the original watermark using the Pixel Recovery Rate of the recovered watermark relative to the original watermark.

11. The method of claim 1 , further comprising: on extracting the recovered watermark, post-processing the received multimedia video data to eliminate effect of the watermark embedment, wherein the post-processing comprises one of the following: smoothing filtering, median filtering, neural network filtering, mathematical morphology filtering and filtering based on fuzzy mathematics methods.

12. The method of claim 1 , further comprising: determining the original watermark, relevant parameters and a step for embedding the original watermark and extracting the recovered watermark through a communication negotiation between the transmitting side and the receiving side.

13. The method of claim 1 , further comprising: determining the original watermark, the relevant parameters and the strategy for embedding the original watermark and extracting the recovered watermark at the transmitting side, and informing the receiving side before communication.

14. The method of claim 2 , wherein for a color image, the original watermark is embedded in a luminance component of the original multimedia data, and wherein for a multi-channel image, the original watermark is embedded in one or more channels of the original multi-channel image data.

15. The method of claim 1 , wherein the original watermark is a bi-level image.