CN101217665A

CN101217665A - A parallel line scanning method of video frequency

Info

Publication number: CN101217665A
Application number: CN 200810032632
Authority: CN
Inventors: 范霞; 刘锦阳; 王蕾睿
Original assignee: Central Academy of SVA Group Co Ltd
Current assignee: Central Academy of SVA Group Co Ltd
Priority date: 2008-01-14
Filing date: 2008-01-14
Publication date: 2008-07-09

Abstract

The invention provides a parallel scanning method for video coefficient. The method, according to Zig-Zag scanning sequence, divides quantized coefficients of a blockette into a plurality of arrays; each array comprises m quantized coefficients; any quantized coefficient An in any array (A1, A2 ... An..., Am): if An is equal to 0, a counter value is plus 1 without outputting number pairs of range and run; if An is not equal to 0, the counter value is x, when the An is the first number which is not 0 in the array, the number pair of range and run (An, x plus n minus 1) is generated and the counter is set to 0; when An is not the first number that is not equal to 0, Au is set (u is equal to or larger than 1 and smaller than n) and is the nearest number which is not equal to 0 before An, the number pair generated by An is (An, n-u-1); number pair (level, run) is output; the process is repeated till the scanning of the blockette is finished, which only needs to consume 1/m of the time in the prior art.

Description

A kind of also line scanning method of video coefficients

Technical field

The invention belongs to the digital audio/video coding field, particularly a kind of also line scanning method of video coefficients.

Background technology

In numerous image encoding agreements, as H.264, AVS etc., infraframe image coder all needs by discrete cosine transform (DCT), is about to image and turns to spectrum expression formula or frequency domain from the expression formula or the transform of spatial domain in space.This is because through conversion, image only needs a spot of data point just can represent; And, can obtain better piece compression because the coefficient that DCT produces is easy to be quantized.After quantification, the most of DCT coefficients in the image array all are null value by intercepting.When using dct transform, the coefficient of the two dimension after the quantification uses Zig-Zag scanning (reading) method that coefficient table is shown one dimension usually, the number (run) of continuous 0 coefficient and the size (Level) of non-0 coefficient is encoded again.

Existing Zig-Zag scanning implementation method, as shown in Figure 1, the order of the numeral scanning in the circle, each clock cycle is only handled data, like this for 8 * 8 quantize block, need just can dispose through 64 clocks, under the demanding situation of real-time of coding, just be difficult to realize real-time coding as the high definition coding.

Summary of the invention

The object of the present invention is to provide a kind of also line scanning method of video coefficients, described method is passed through and line scanning, thereby saves the clock cycle greatly, well satisfies the real-time requirement of encoding.

The object of the present invention is achieved like this: a kind of also line scanning method of video coefficients, described method is after discrete cosine transform coefficient is quantized, enter the process of finishing before the coding that 8 * 8 two-dimensional image sub-prime pieces is converted to the one dimension arrangement mode, described method relates to input temporary register, scanning monitor, counter and output storage, and described and line scanning method is achieved in that

Step 1, according to the order of Zig-Zag scanning, 8 * 8 sub-piece quantization parameters are divided into some arrays, each array comprises m quantization parameter, if last group is discontented with the m number, then supplies with 0;

Step 2, with counter zero setting, begin input temporary register quantization parameter is scanned;

Step 3, for the described arbitrary array of step 1 [A1, A2 ... An...Am], wherein arbitrary quantization parameter An:

If a) An=0, not output amplitude and number of runs to (level, run);

B) if An ≠ 0, the value of this hour counter is x, then when An for this array first be not 0 severals the time, it is 0 that there is the n-1 number its front, then the generation (level, run) several to be (An, x+n-1), the value with counter is changed to 0 simultaneously; When An for this array non-first be not 0 severals the time, establish several Au (1≤u＜n) is before An not to be 0 number apart from nearest one of An, then the An generation (level, run) several to be (An, n-u-1);

Step 4, from output storage output (level, run) several right;

Step 5, the mobile coefficient storage address that quantizes, repeating step 3～step 4 is until the scanning of finishing this sub-piece.

In described output storage, parallel m individual (level, run) the several right registers deposited of delegation.

The present invention has been owing to adopted above-mentioned technical scheme, makes in the prior art clock only handle a data conditions and becomes and can handle m data simultaneously, therefore saved the clock cycle greatly, can satisfy the real-time requirement of encoding as far as possible.

Description of drawings

The also line scanning method of video coefficients of the present invention is provided in detail by following embodiment and accompanying drawing.

Fig. 1 is general Zig-Zag scanning schematic diagram;

Fig. 2 is the scanning schematic diagram of the embodiment of the invention.

Embodiment

Below will the also line scanning method of a kind of video coefficients of the present invention be described in further detail.

Also line scanning method according to a kind of video coefficients provided by the invention, described method is after discrete cosine transform coefficient is quantized, enter the process of finishing before the coding that 8 * 8 two-dimensional image sub-prime pieces is converted to the one dimension arrangement mode, described method relates to input temporary register, scanning monitor, counter and output storage, and described and line scanning method is achieved in that

If a) An=0, not output amplitude and number of runs to (level, run);

Step 4, from output storage output (level, run) several right;

Step 5, repeating step 3～step 4 are until the scanning of finishing this sub-piece.

Suppose m=2 in the present embodiment, i.e. two-way and line scanning is divided into 32 arrays with 8 * 8 sub-piece quantization parameters in step 1, is shown [0,1], [2,3], [4,5] ... [62,63] with the address table of each quantization parameter; Whether for the value of the pairing quantization parameter in address in the above array is zero, can be divided into four kinds of situations, i.e. [P, 0], [0, Q], [S, T] or [0,0], P wherein, Q, S, T are a certain non-vanishing number.

In step 3, scanning process need judge address indication quantization parameter meets following which kind of situation in the above array:

A) when meeting [P, 0] form, promptly first number is not 0, establish this moment Counter Value be x, then form one group (level, run) several to be (P, x); Second number is 0, does not form then that (level run), but is changed to 1 with counter;

B) when meeting [0, Q] form, promptly to be 0, the second be not 0 to first number, and establishing this moment Counter Value is x, then form one group (level, run) several to being that (Q x+1), puts 0 with counter simultaneously;

C) when meeting [S, T] form, promptly first number and second number average are not 0, and establishing this moment Counter Value is x, then form two groups (level, run) several to (S x) and (T, 0), puts 0 with counter simultaneously;

D) when meeting (0,0) form, promptly first number and second number are 0, then do not form (level, run) several right, only counter is added 2.

After the quantization parameter that the first group address data are deposited is handled, the data in the input temporary register be carried out shifting function according to the order of fine line among Fig. 2 or fine dotted line arrow indication, can read correct data to guarantee next clock.In Fig. 2, the quantification of odd address is moved according to the direction shown in the fine line arrow, and the quantification of even address is moved according to the direction shown in the fine dotted line arrow.Moving direction when the heavy line arrow is sent into quantization parameter for the outside;

In output storage, delegation walks abreast and has deposited two (level, run) several right registers.

In the present embodiment since parallel processing two data, therefore only need just can finish the scanning of 64 quantization parameter, thereby save 64-64/m=32 clock cycle through 32 clock cycle.

Claims

A video coefficients and line scanning method, described method is after discrete cosine transform coefficient is quantized, enter the process of finishing before the coding that 8 * 8 two-dimensional image sub-prime pieces is converted to the one dimension arrangement mode, described method comprises provides an input temporary register, scanning monitor, counter and output storage, it is characterized in that described and line scanning method also comprises the following steps:

Step 1, according to the order of Zig-Zag scanning, 8 * 8 sub-piece quantization parameters are divided into some arrays, each array comprises m quantization parameter, if last group is discontented with the m number, then supplies with 0;

Step 2, with counter zero setting, scanning monitor begins input temporary register quantization parameter is scanned;

Step 3, for the described arbitrary array of step 1 [A1, A2 ... An...Am], wherein arbitrary quantization parameter An:

If a) An=0, not output amplitude and number of runs to (level, run);

B) if An ≠ 0, the value of this hour counter is x, then when An for this array first be not 0 severals the time, it is 0 that there is the n-1 number its front, then the generation (level, run) several to be (An, x+n-1), the value with counter is changed to 0 simultaneously; When An for the non-head of this array be not 0 severals the time, establish several Au (1≤u＜n) is before An not to be 0 number apart from nearest one of An, then the An generation (level, run) several to be (An, n-u-1);

Step 4, from output storage output (level, run) several right;

Step 5, the mobile coefficient storage address that quantizes, repeating step 3～step 4 is until the scanning of finishing this sub-piece.
A kind of video coefficients as claimed in claim 1 and line scanning method, in described output storage, delegation is parallel deposits m (level, run) several right registers.