CN1992893A - Decoder, method for adjusting decoding calculating quantity and computer readable media - Google Patents

Abstract

The invention relates to a coder for adjusting the code calculation, relative method and computer readable medium, wherein the coder comprises parameter generator, summing unit, and complexity calculator, while it can adjust the code calculation via the first code parameter; the first code parameter is generated by video data; the method and computer readable medium comprise that: the parameter generator generates image quality parameters; the summing unit sums the first code parameter and image quality image to generate the second code parameter; the complexity calculator via the second coding parameter calculates out the complexity, to generate the third code parameter and refresh parameter; the parameter generator via refresh parameter refreshes the image quality parameter; the coder uses the third code parameter to code video.

Description

Adjust encoder, method and the computer-readable media thereof of decoding calculating quantity

Technical field

The present invention relates to a kind of encoder, method and computer-readable media thereof of adjustment decoding calculating quantity, in more detail, is to adjust encoder, method and the computer-readable media thereof of decoding calculating quantity according to decoding complex degree.

Background technology

In recent years, the digital communication medium comprise that the transmission capacity of cable TV, satellite, internet etc. increases rapidly.Though on capacity, constantly increase, yet these transmission capacities are too little for the high-quality video data of transmission uncompressed.To the demand of multichannel number, mobile video, high-quality video, high-resolution video under the more and more strong situation, the rate of rise of digital communication media capabilities can not satisfy the needs of these high-quality video data far away now.

Except continuation broke through on transmission capacity, researching and developing more efficient video compression scheme was another kind of solution.Video compression standard the earliest just occurred in the eighties, via continuous improvement, the video compression standard of recent years can provide rather good squeezed quality and quite high compression ratio, for example MEPG 2 video compression standards, MEPG 4 video compression standards and H.264 video compression standard etc., its compressed capability are to reach by the coding parameter that block mode (block mode) and dynamic vector (motion vector) are formed.

Fig. 1 is known encoder internal circuit block diagram.Please refer to Fig. 1, known encoder operation principle is as described below: video frame (video frame) 100 inputs to this encoder, produce afterwards composite video frame 102 with adder 101 and reference video frame 122 (as the back narration) addition, this composite video frame 102 inputs to converting unit 103, converting unit 103 converts composite video frame 102 to video frame switching signal 104 for using discrete cosine transform, 104 of video frame switching signals are to remove via the high-frequency signal that quantifying unit 105 will be difficult for being discovered by human eye, produce video frame quantized signal 106, video frame quantized signal 106 is tabled look-up to encode via entropy coding unit 107 and is produced video frame code signal 108 afterwards, and video frame code signal 108 is through producing quantization parameter 110 after 109 decodings of entropy decoding unit, quantization parameter 110 is via producing conversion coefficient 112 after inverse quantization unit 111 inverse quantizations, this conversion coefficient 112 is again via producing estimation video frame error signal 114 after inverse transform unit 113 inverse transform, this estimation video frame error signal 114 and reference video frame 122 promptly produce decoded video frame 116 after adder 115 additions.This decoded video frame 116 will deposit in to video frame buffering area 117, and video frame buffering area 117 in 100 inputs of next video frame output decoder video frame 118 (being previous decoded video frame 116) to dynamic compensation unit 119, video frame 100 inputs to after dynamic estimation and pattern decision unit 121 and 118 computings of decoded video frame, produce coding parameter 120, this coding parameter 120 and decoded video frame 118 by 119 computings of dynamic compensation unit after the aforementioned reference video frame 122 of output.Coding parameter 120 is tabled look-up to encode via entropy coding unit 123 simultaneously and is produced afterwards code signal 124, this code signal 124 and video frame code signal 108 via 125 computings of bit streams assembled unit after, produce encoded video bit streams 126, this encoded video bit streams 126 promptly be this encoder coded and video compression data.

Among aforesaid compression process, the factor that influences image quality and compression ratio maximum promptly is a coding parameter 120.With video compression standard H.264 is example, and coding parameter 120 has comprised the dynamic vector and the block mode factor.Dynamic vector produces according to the following relationship formula:

$V^{*}(B,M)=\underset{V\∈\sup \left\{V\right\}}{\arg \min }{J}_{\mathrm{MODE}}^{R,D}\left(V\right|B,M)$

$=\underset{V\∈\sup \left\{V\right\}}{\arg \min }\{D_{\mathrm{DFD}}\left(V\right|B,M)+{\mathrm{\λ}}_{\mathrm{MOTION}}{R}_{\mathrm{MOTION}}\left(V\right|B,M)\}$

V wherein ^*Be dynamic vector, the option of braces " { } " expression dynamic vector, its according to pixel coverage of searching, can reference picture and the direction of prediction calculate, B is macro zone block (macroblock) parameter, M is macro zone block coding mode configuration (macroblock coding mode allocation) parameter, D _DFDBe that present macro zone block and dynamic compensation are rebuild the difference value between the macro zone block of back, it represents quality, λ _MOTIONBe the blue thatch multiplier (Lagrange Multiplier) of the glug between bit rate and the image quality, R _MOTIONThe predicted value of expression bit rate, J _MODE ^{R, D}(M) then be the bit rate of selected dynamic vector and the integrated cost letter formula of image quality.Block mode produces according to the following relationship formula:

$M^{*}(\mathrm{MB},\mathrm{QP})=\underset{M\∈\sup \left\{M\right\}}{\arg \min }{J}_{\mathrm{MODE}}^{R,D}\left(M\right|\mathrm{MB},\mathrm{QP})$

$=\underset{M\∈\sup \left\{M\right\}}{\arg \min }\{D_{\mathrm{REC}}\left(M\right|\mathrm{MB},\mathrm{QP})+{\mathrm{\λ}}_{\mathrm{MODE}}{R}_{\mathrm{REC}}\left(M\right|\mathrm{MB},\mathrm{QP})\}$

M wherein ^*Being block mode, is the option of block mode in the braces " { } ", and MB then is selected block mode, and QP then is the selected following image quality parameter of block mode, D _RECBe that present macro zone block and dynamic compensation are rebuild the difference value between the macro zone block of back, it represents quality, λ _MODEBe the blue thatch multiplier of the glug between bit rate and the image quality, R _RECIt is the predicted value of block mode bit rate when being M.Dynamically estimation and pattern decision unit 121 is to come calculation code parameter 120 according to the aforementioned dynamic vector and the relational expression of block mode.

Though coding can compress the coding video frequency data of high image quality and high compression rate in this way, but do not consider the decoding capability of decoding end.When the computing capability of decoding end is not enough, will make decoding end can't decode video data smoothly.Therefore how to carry out suitable coding, make the decoding of video data only need utilize a spot of calculation resources and operation time to reach, and then the computational load of reduction decoding end is the target that this field need be made great efforts at video data.

Summary of the invention

In order to solve aforementioned problem, the present invention proposes a dynamic estimation and a pattern determining method of considering decoding complex degree, make the known coding parameter can be according to the factor of decoding complex degree, allow the video frame coding of encoder can reduce the computing capability of decoding end, and naked eyes are difficult for discovering the image quality of its loss.

One of the present invention purpose be to provide a kind of according to first coding parameter adjusting the encoder of decoding calculating quantity, this first coding parameter is produced by video data and is used for the parameter of coding for known encoder.This encoder packet containing parameter generation unit, adder unit and complexity computing unit.This parameter generating unit initially produces image quality parameter.This adder unit is in order to receiving this first coding parameter and this image quality parameter, and produces second coding parameter.This complexity computing unit carries out complexity according to this second coding parameter and calculates, and produces the 3rd coding parameter and undated parameter.This parameter generating unit upgrades this image quality parameter according to this undated parameter, this encoder then with the 3rd coding parameter to this coding video data.

Another object of the present invention be to provide a kind of according to first coding parameter adjusting the method for decoding calculating quantity, this first coding parameter is produced by video data and is used for the parameter of coding for known encoder.This method comprises the following step: produce image quality parameter; Produce second coding parameter according to this first coding parameter and this image quality parameter; Carry out complexity according to this second coding parameter and calculate, produce the 3rd coding parameter and undated parameter; Upgrade this image quality parameter according to this undated parameter; And use the 3rd coding parameter to carry out video coding.

Another object of the present invention is to provide a kind of computer-readable media, stores computer program in order to carry out above-mentioned method.

Behind the execution mode of consulting accompanying drawing and description subsequently, the person of ordinary skill in the field just can understand other purpose of the present invention, and the present invention's technological means and execution mode.

Description of drawings

Fig. 1 is known encoder internal circuit block diagram;

Fig. 2 is the circuit block diagram of the present invention's first embodiment;

Fig. 3 is the flow chart of the present invention's second embodiment;

Fig. 4 is the flow chart of the generation image quality parameter of second embodiment; And

Fig. 5 is generation the 3rd coding parameter of second embodiment and the flow chart of undated parameter.

The main element description of symbols

100: input video frame 101,115,205: adder unit

102: composite video frame 103: converting unit

104: video frame switching signal 105: quantifying unit

106: video frame quantized signal 107,123: entropy coding unit

108: video frame code signal 109: the entropy decoding unit

110: quantization parameter 111: inverse quantization unit

112: conversion coefficient 113: the inverse transform unit

114: estimation video frame error signal 116: decoded video frame

117: video frame buffering area 118: last decoded video frame

119: dynamic compensation unit 120: coding parameter

121: dynamically estimation and pattern determine unit 122: the reference video frame

124: code signal 125: the bit streams assembled unit

126: encoded video bit streams 200: video data

201: the estimation unit

Coding parameter 203 in 202: the first: the parameter generating unit

204: preset value 206: image quality parameter

207: 208: the second coding parameters of complexity computing unit

210: 212: the three coding parameters of undated parameter

Embodiment

The present invention's first embodiment further adjusts the encoder of decoding calculating quantity for a kind of according to known coding parameter, and this known coding parameter is produced by video data, is coding parameter shown in Figure 1 120.This embodiment can handle time pixel (sub-pixel), so the compression standard that is suitable for comprises H.264 compression standard, MPEG 2 compression standards and MPEG 4 compression standards etc.Fig. 2 is the dynamic estimation of this encoder and the schematic diagram of pattern decision unit (corresponding to dynamic estimation and the pattern decision unit 121 of Fig. 1).As shown in the figure, this dynamic estimation and pattern decision unit comprises estimation unit 201, parameter generating unit 203, adder unit 205 and complexity computing unit 207.Estimation unit 201 calculates first coding parameter 202 in order to receiving video data 200 and according to video data 200, and wherein video data 200 video frame 100, the first coding parameters 202 that are Fig. 1 are coding parameter shown in Figure 1 120.

Parameter generating unit 203 is in order to produce image quality parameter 206 according to preset value 204 and undated parameter 210.This preset value 204 can be stored in the parameter generating unit 203 in advance, or is directly imported by the user as shown in Figure 2.This preset value 204 in order to 200 of this video datas of decision coding can tolerance the distortion factor, this distortion factor with utilize coding parameter shown in Figure 1 120 to encode merely to compare, for example preset value 204 is compared with known technology for 0.3dB represents the present invention's the coded image of encoder, and its distortion level that can accept mostly is 0.3dB most.Undated parameter 210 is produced by complexity computing unit 207 as described later, inputs to the interior counter in parameter generating unit 203, compares with preset value 204 again.The storage access complexity is adjusted according to preset value 204 and undated parameter 210 in parameter generating unit 203, and according to this storage access complexity generation image quality parameter 206, complexity when wherein the storage access complexity is decoded with decoding end is relevant, the storage access complexity is higher, complexity during the decoding end decoding is higher, the storage access complexity is lower, and the complexity during the decoding end decoding is lower.In more detail, parameter generating unit 203 is according to following relationship formula computed image mass parameter 206:

$V_c^{*}(B,M)=\underset{v\∈\sup \left\{V\right\}}{\arg \min }{J}_{\mathrm{MOTION}}^{R,D,C}\left(V\right|B,M)$

$=\underset{V\∈\sup \left\{V\right\}}{\arg \min }\{J_{\mathrm{MOTION}}^{R,D}\left(V\right|B,M)+{\mathrm{\γ}}_{\mathrm{MOTION}}{C}_{\mathrm{MOTION}}\left(V\right|B,M)\}$

V wherein _c ^*Represent selected dynamic vector, the option of braces " { } " expression dynamic vector, be in C different with known technology _MOTIONRepresent the letter formula of decoding end complexity, be used for representing the cost of selected dynamic vector, γ _MOTIONBe the glug orchid multiplier now of expression storage access complexity, be used for adjusting the cost of decoding complex degree, J _MOTION ^{R, D}, C (V) then is an integrated cost letter formula of considering bit rate R, image quality D and decoding end computation complexity C.By this glug orchid computing now, this embodiment takes the storage access complexity into account.

205 of adder units are that first coding parameter 202 and image quality parameter 206 are done add operation and drawn second coding parameter 208.

Complexity computing unit 207 receives second coding parameter 208 and produces undated parameter 210 and the 3rd coding parameter 212.The 3rd coding parameter 212 exports dynamic compensation unit 119 and the entropy coding unit 123 of Fig. 1 to, and in order to provide the required parameter of video data 200 codings, undated parameter 210 is then feedback to parameter generating unit 203, in order to update image mass parameter 206.In more detail, complexity computing unit 207 is adjusted decoding complex degree according to second coding parameter 208, produce the 3rd coding parameter 212 and undated parameter 210 according to this decoding complex degree again, complexity when wherein decoding complex degree is also decoded with decoding end is relevant, this decoding complex degree is higher, complexity during the decoding end decoding is higher, and this decoding complex degree is lower, and the complexity during the decoding end decoding is lower.In more detail, complexity computing unit 207 calculates undated parameter 210 and the 3rd coding parameter 212 according to the following relationship formula:

$M_c^{*}(\mathrm{MB},\mathrm{QP})=\underset{M\∈\sup \left\{M\right\}}{\arg \min }{J}_{\mathrm{MODE}}^{R,D,C}\left(M\right|\mathrm{MB},\mathrm{QP})$

$=\underset{M\∈\sup \left\{M\right\}}{\arg \min }\{J_{\mathrm{MODE}}^{R,D}\left(M\right|\mathrm{MB},\mathrm{QP})+{\mathrm{\γ}}_{\mathrm{MODE}}{C}_{\mathrm{MODE}}\left(M\right|\mathrm{MB})\}$

M wherein _c ^*Be selected block mode, braces " { } " is the option of block mode, be in C different with known technology _MODEThen be the cost of the storage access complexity of each block mode, γ _MODEBe the glug orchid multiplier now of expression decoding complex degree, be used for adjusting the cost of storage access complexity, J _MOTION ^{R, D}, C (V) then is the integrated cost letter formula of bit rate R, image quality D and decoding end computation complexity C.By this glug orchid computing now, to produce undated parameter 210 and the 3rd coding parameter 212.

The second embodiment of the present invention be a kind of according to first coding parameter to adjust the method for decoding calculating quantity, first coding parameter is produced by video data, is coding parameter shown in Figure 1 120, the method as shown in Figure 3.When execution in step 301, initially produce image quality parameter.Then execution in step 303 produces second coding parameter according to first coding parameter and image quality parameter, for example first coding parameter and image quality parameter is carried out add operation and gets.Then execution in step 305 is carried out complexity according to second coding parameter and is calculated, and produces the 3rd coding parameter and undated parameter.Follow execution in step 307, according to undated parameter update image mass parameter.Follow execution in step 309, carry out the coding of video data with the 3rd coding parameter.

The image quality parameter of step 301 produces according to preset value, the distortion factor of this video data when this preset value promptly determines to encode, and itself and first embodiment are as good as, so do not give unnecessary details.As shown in Figure 4, step 301 can also comprise the following step: when execution in step 401, set preset value.Then execution in step 403 is adjusted the storage access complexity according to preset value and the described undated parameter of leading portion.Then execution in step 405 produces image quality parameter according to the storage access complexity.

As shown in Figure 5, step 305 item also comprises the following step: when execution in step 501, receive second coding parameter.Then execution in step 503 is adjusted decoding complex degree according to second coding parameter.Then execution in step 505 produces the 3rd coding parameter and undated parameter according to decoding complex degree.

Producing image quality parameter, the 3rd coding parameter and undated parameter in the step 301 and 305 also can utilize as the glug orchid computing now as described in first embodiment.

H.264 aforementioned method can be applied in compression standard, MPEG 2 compression standards and MPEG 4 compression standards equally.

Aforementioned method can be utilized a kind of computer-readable media, and it stores computer program and carries out aforementioned step.This computer-readable media can be floppy disk, hard disk, CD, dish, tape, the Storage Media that can think and have identical function easily by the database or the person of ordinary skill in the field of network access with oneself.

From the above, the present invention can improve the shortcoming of the known encoder that uses, consider decoding complex degree, make encoder when carrying out video data encoding, not only keep image quality, make naked eyes be unlikely to pick out difference, can also reduce simultaneously the computing cost of decoding end, so the situation that can't decode smoothly will can not take place, in addition, the present invention also saves the power supply requirement of decoding end.

Above-mentioned embodiment only is used for exemplifying the present invention's execution mode, and explaination the present invention's technical characterictic, is not the category that is used for limiting the present invention.The scope that the change that any person of ordinary skill in the field can finish easily or the arrangement of isotropism all belong to the present invention is advocated, the present invention's interest field should be as the criterion with claim.

Claims (18)

1. One kind according to first coding parameter to adjust the encoder of decoding calculating quantity, this first coding parameter is produced by video data, it is characterized in that this encoder comprises:

   The parameter generating unit produces image quality parameter;

   Adder unit in order to receiving this first coding parameter and this image quality parameter, and produces second coding parameter; And

   The complexity computing unit carries out complexity according to this second coding parameter and calculates, and produces the 3rd coding parameter and undated parameter;

   Wherein, this parameter generating unit upgrades this image quality parameter according to this undated parameter, this encoder with the 3rd coding parameter to this coding video data.
2. 2. the encoder according to claim 1 is characterized in that this parameter generating unit produces this image quality parameter according to preset value, the distortion factor of this this video data of preset value decision coding.
3. 3. the encoder according to claim 2 is characterized in that this parameter generating unit according to this preset value and this undated parameter adjustment storage access complexity, and produces this image quality parameter according to this storage access complexity.
4. 4. the encoder according to claim 1 is characterized in that this adder unit carries out add operation with this first coding parameter and this image quality parameter.
5. 5. the encoder according to claim 1 is characterized in that this complexity computing unit according to this second coding parameter adjustment decoding complex degree, and produces the 3rd coding parameter and this undated parameter according to this decoding complex degree.
6. 6. the encoder according to claim 1, the compression standard that it is characterized in that this encoder is wherein a kind of compression standard of compression standard, MPEG 2 compression standards and MPEG 4 compression standards H.264.
7. One kind according to first coding parameter to adjust the method for decoding calculating quantity, this first coding parameter is produced by video data, it is characterized in that the method includes the steps of:

   Produce image quality parameter;

   Produce second coding parameter according to this first coding parameter and this image quality parameter;

   Carry out complexity according to this second coding parameter and calculate, produce the 3rd coding parameter and undated parameter;

   Upgrade this image quality parameter according to this undated parameter; And

   Carry out video coding with the 3rd coding parameter.
8. 8. the method according to claim 7 is characterized in that this image quality parameter produces according to preset value, the distortion factor of this this video data of preset value decision coding.
9. 9. described according to Claim 8 method is characterized in that the step of this generation image quality parameter comprises the following step:

   Adjust the storage access complexity according to this preset value and this undated parameter; And

   Produce this image quality parameter according to this storage access complexity.
10. 10. the method according to claim 7 is characterized in that this step that produces second coding parameter comprises the following step: this first coding parameter and this image quality parameter are carried out add operation.
11. 11. the method according to claim 7 is characterized in that this step that produces the 3rd coding parameter and undated parameter comprises the following step:

    Adjust decoding complex degree according to this second coding parameter; And

    Produce the 3rd coding parameter and this undated parameter according to this decoding complex degree.
12. 12. the method according to claim 7 is characterized in that this method is applied to H.264 wherein a kind of compression standard of compression standard, MPEG 2 compression standards and MPEG 4 compression standards.
13. 13. a computer-readable media, it is a kind of according to the method for first coding parameter with the adjustment decoding calculating quantity in order to carry out to store computer program, and this first coding parameter is produced by video data, it is characterized in that the method includes the steps of:

    Produce image quality parameter;

    Produce second coding parameter according to this first coding parameter and this image quality parameter;

    Carry out complexity according to this second coding parameter and calculate, produce the 3rd coding parameter and undated parameter;

    Upgrade this image quality parameter according to this undated parameter; And

    Carry out video coding with the 3rd coding parameter.
14. 14. the computer-readable media according to claim 13 is characterized in that this image quality parameter produces according to preset value, the distortion factor of this this video data of preset value decision coding.
15. 15. the computer-readable media according to claim 14 is characterized in that the step of this generation image quality parameter comprises the following step:

    Adjust the storage access complexity according to this preset value and this undated parameter: and

    Produce this image quality parameter according to this storage access complexity.
16. 16. the computer-readable media according to claim 13 is characterized in that this step that produces second coding parameter comprises the following step: this first coding parameter and this image quality parameter are carried out add operation.
17. 17. the computer-readable media according to claim 13 is characterized in that this step that produces the 3rd coding parameter and undated parameter comprises the following step:

    Adjust decoding complex degree according to this second coding parameter; And

    Produce the 3rd coding parameter and this undated parameter according to this decoding complex degree.
18. 18. the computer-readable media according to claim 13 is characterized in that this method is applied to H.264 wherein a kind of compression standard of compression standard, MPEG 2 compression standards and MPEG 4 compression standards.

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