CN103428492A - Fast zig-zag scanning method for high-definition AVS coding - Google Patents

Abstract

The invention relates to a fast zig-zag scanning method for high-definition AVS coding. The method includes the steps of 1, during AVS coding, according to a processing sequence of zig-zag scanning quantization coefficients, calculating the number p of nonzero coefficients in a quantization coefficient matrix during the process of inputting the quantization coefficient matrix to an AVS entropy coding module; 2, after inputting of the quantization coefficient matrix, subjecting the quantization coefficient matrix to zig-zag scanning, and calculating the number q of scanned nonzero coefficients; 3, judging the relation of p to q; when q is smaller than p, continuing zig-zag scanning for the quantization coefficient matrix; when q is equal to p, ending the zig-zag scanning for the quantization coefficient matrix; 4, after completion of the zig-zag scanning, continuing to perform AVS entropy coding. The method has the advantages that scanning tail zero coefficients is avoided so that zig-zag scanning speed is increased greatly; coding time is reduced greatly, and high-definition video coding can be achieved.

Description

A kind of method that in high definition AVS coding, zig-zag scans fast

Technical field:

The present invention relates to a kind of method that in high definition AVS coding, zig-zag scans fast, belong to multimedia technical field.

Background technology:

Along with the development of multimedia technology, people are more and more higher to the compression requirement of multimedia video, and new video encoding standard is arisen at the historic moment.AVS is the advanced video encoding standard of China's independent development, and the entropy coding, as the afterbody of whole AVS Video coding, occupies an important position in Video coding, and its coding efficiency can have influence on the operation of whole encoder.

Zig-zag scanning is an important part in the entropy coding, at first AVS prediction residual coefficient passes through Integer DCT Transform and quantification, the quantization parameter of quantizer output shows the rule that the low frequency coefficient amplitude is large, the high frequency coefficient amplitude is little, through the output after quantizing, it is a sparse matrix that comprises minority nonzero coefficient and a large amount of zero coefficient, be scanned into the rearrangement order by zig-zag, purpose is that nonzero coefficient is put together.For 8 * 8 coefficient matrixes, because the number of its nonzero coefficient is uncertain, in traditional way, be that 64 coefficients are carried out to whole scanning, comprise a large amount of zero coefficients in end end due to matrix, scanning for end end zero coefficient is nonsensical, therefore traditional scan method can take a large amount of clock cycle, and the speed of the coding that slowed down, be unfavorable for the high definition coding.Therefore how to accelerate zig-zag scanning, reduce insignificant sweep time, quite important for high definition AVS coding.

Summary of the invention:

For the deficiencies in the prior art, the invention provides a kind of method that in high definition AVS coding, zig-zag scans fast.The method can realize carrying out fast zig-zag scanning, greatly accelerates the speed of entropy coding, has also just greatly improved the speed of whole Video coding, is conducive to realize high definition AVS coding.

Technical scheme of the present invention is as follows:

A kind of method that in high definition AVS coding, zig-zag scans fast comprises that step is as follows:

(1) in the AVS coding, the prediction residual coefficient is at first according to prior art process Integer DCT Transform and quantification, a quantization parameter matrix that contains zero coefficient of quantizer output, before AVS entropy coding, above-mentioned quantization parameter matrix is reordered: the nonzero coefficient in the quantization parameter matrix is put together, in the AVS coding, adopt the quantization parameter processing sequence of zig-zag scanning, in to the input of AVS entropy coding module, quantizing the process of coefficient matrix, in the statistic quantification coefficient matrix, the number of nonzero coefficient, be designated as p; The present invention adopts the quantization parameter processing sequence of zig-zag scanning, and this scanning sequency is more easily followed the variation of non-zero quantized coefficients information;

(2) after completing the input of quantification coefficient matrix, the quantization parameter matrix is carried out to zig-zag scanning, in the process of scanning, the number of the nonzero coefficient that statistics scans, be designated as q;

(3) relation of judgement p and q:

In the time of q<p, continue the quantization parameter matrix is carried out to zig-zag scanning;

In the time of q=p, finish the zig-zag scanning to the quantization parameter matrix; Traditional zig-zag scanning will scan last coefficient of 8 * 8 quantization parameter matrixes always, scan 64 times, due in 8 * 8 general quantization parameter matrixes, p is much smaller than 64, therefore with traditional zig-zag scanning method, compare, utilize this quick zig-zag scanning method, can greatly add fast scan speed, also just accelerated the speed of coding simultaneously;

(4) after completing zig-zag scanning, proceed AVS entropy coding.

The invention has the advantages that:

Method of the present invention avoids scanning the zero coefficient of end section, has therefore greatly accelerated the speed of zig-zag scanning, and realize quick zig-zag scanning: in the quantization parameter matrix, the end end comprises 0 a large amount of coefficients.Due to improving constantly that the AVS field of video applications requires, high definition AVS Video coding has become main development trend, adopts this invention, can greatly reduce the scramble time, is conducive to realize the HD video coding.

The accompanying drawing explanation:

Fig. 1 is traditional zig-zag scanning;

Fig. 2 is realization flow figure of the present invention;

Fig. 3 is the implementation structure figure of the present invention's " nonzero coefficient statistical module ";

Fig. 4 is the deterministic process of the nonzero coefficient of the quick zig-zag scanning of the present invention;

Fig. 5 is the judge module structure chart of the nonzero coefficient that scans of zig-zag;

The effect schematic diagram that Fig. 6 is the quick zig-zag scanning of the present invention.

Embodiment:

Below in conjunction with accompanying drawing, the present invention is further illustrated, but be not limited to this.

Embodiment 1,

A kind of method that in high definition AVS coding, zig-zag scans fast comprises that step is as follows:

(1) in the AVS coding, the prediction residual coefficient is at first according to prior art process Integer DCT Transform and quantification, a quantization parameter matrix that contains zero coefficient of quantizer output, before AVS entropy coding, above-mentioned quantization parameter matrix is reordered: the nonzero coefficient in the quantization parameter matrix is put together, in the AVS coding, adopt the quantization parameter processing sequence of zig-zag scanning, in to the input of AVS entropy coding module, quantizing the process of coefficient matrix, in the statistic quantification coefficient matrix, the number of nonzero coefficient, be designated as p;

(2) after completing the input of quantification coefficient matrix, the quantization parameter matrix is carried out to zig-zag scanning, in the process of scanning, the number of the nonzero coefficient that statistics scans, be designated as q;

(3) relation of judgement p and q:

In the time of q<p, continue the quantization parameter matrix is carried out to zig-zag scanning;

In the time of q=p, finish the zig-zag scanning to the quantization parameter matrix;

(4) after completing zig-zag scanning, proceed AVS entropy coding.

As shown in Figure 1, in 8 * 8 quantization parameter matrixes after having quantized, 9 nonzero coefficients are arranged, for traditional zig-zag scanning, will be 64 whole been scanned of coefficient, if coefficient of 1 intermittent scanning needs 64 clock cycle could this quantization parameter matrix-scanning is complete.

As shown in Figure 2, according to realization flow of the present invention, in the input process of quantization parameter matrix, insert " nonzero coefficient statistical module ", after the quantization parameter input, just obtained the number of nonzero coefficient, be designated as variable p.

As shown in Figure 3, be the implementation structure figure of " nonzero coefficient statistical module ".Wherein cin is the quantization parameter of input.

As shown in Figure 4, be the deterministic process of the nonzero coefficient of the quick zig-zag of the present invention scanning, wherein cout is the quantization parameter scanned, the number that p is the nonzero coefficient that obtained by " nonzero coefficient statistical module " in input process.When zig-zag scans, the coefficient that scans out of judgement, send into " scanning judge module ", if non-zero, and q=q+1, if zero, q is constant.When q<p, scanning continues, and when q=p, finishes zig-zag scanning.

The judge module structure chart of the nonzero coefficient scanned for zig-zag as shown in Figure 5.

As shown in Figure 6, effect schematic diagram for the quick zig-zag scanning of the present invention, in Fig. 6, if each clock scan coefficient, only need 15 clocks just can finish zig-zag scanning, and traditional way needs 64 clocks, so the present invention has accelerated zig-zag scanning greatly, also just accelerate the speed of coding, be conducive to realize high definition AVS Video coding.

Claims (1)

1. the method for zig-zag scanning fast in high definition AVS coding comprises that step is as follows:

(1) in the AVS coding, the prediction residual coefficient is at first according to prior art process Integer DCT Transform and quantification, a quantization parameter matrix that contains zero coefficient of quantizer output, before AVS entropy coding, above-mentioned quantization parameter matrix is reordered: the nonzero coefficient in the quantization parameter matrix is put together, in the AVS coding, adopt the quantization parameter processing sequence of zig-zag scanning, in to the input of AVS entropy coding module, quantizing the process of coefficient matrix, in the statistic quantification coefficient matrix, the number of nonzero coefficient, be designated as p;

(2) after completing the input of quantification coefficient matrix, the quantization parameter matrix is carried out to zig-zag scanning, in the process of scanning, the number of the nonzero coefficient that statistics scans, be designated as q;

(3) relation of judgement p and q:

In the time of q<p, continue the quantization parameter matrix is carried out to zig-zag scanning;

In the time of q=p, finish the zig-zag scanning to the quantization parameter matrix;

(4) after completing zig-zag scanning, proceed AVS entropy coding.

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