CN107040786B - A kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field - Google Patents

A kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field Download PDF

Info

Publication number
CN107040786B
CN107040786B CN201710145997.3A CN201710145997A CN107040786B CN 107040786 B CN107040786 B CN 107040786B CN 201710145997 A CN201710145997 A CN 201710145997A CN 107040786 B CN107040786 B CN 107040786B
Authority
CN
China
Prior art keywords
motion vector
time
domain
frame
airspace
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201710145997.3A
Other languages
Chinese (zh)
Other versions
CN107040786A (en
Inventor
胡永健
蔡梓哲
刘琲贝
王宇飞
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
South China University of Technology SCUT
Original Assignee
South China University of Technology SCUT
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by South China University of Technology SCUT filed Critical South China University of Technology SCUT
Priority to CN201710145997.3A priority Critical patent/CN107040786B/en
Publication of CN107040786A publication Critical patent/CN107040786A/en
Application granted granted Critical
Publication of CN107040786B publication Critical patent/CN107040786B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/46Embedding additional information in the video signal during the compression process
    • H04N19/467Embedding additional information in the video signal during the compression process characterised by the embedded information being invisible, e.g. watermarking
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N17/00Diagnosis, testing or measuring for television systems or their details

Abstract

The invention discloses a kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field, steps are as follows: decoding video extracts the compressed domains such as coding unit division, motion vector to P frame;Motion vector scanning chain is generated, symbiosis frequency abstraction airspace motion vector correlative character is utilized;According to the motion-vector prediction technology in H.265/HEVC, information calculate the time domain prediction motion vector of current prediction unit by same position prediction unit and its at a distance from reference frame etc.;It is poor that time domain prediction motion vector and current motion vector are made, and extracts relativity of time domain feature;Candidate video frame is chosen according to the relationship of motion complexity and time-space domain correlation integrated value;Adaptively selected airspace or time-domain motion vector correlative character are as final classification feature;Finally trained and Classification and Identification.The present invention utilizes the motion-vector prediction feature in H.265/HEVC, creatively adaptively selected to the progress of spatially and temporally motion vector correlative character, effectively improves steganalysis verification and measurement ratio.

Description

A kind of H.265/HEVC video steganalysis adaptively selected based on space-time characteristic of field Method
Technical field
The present invention relates to the Steganalysis fields in video compress domain, and in particular to one kind is adaptive based on space-time characteristic of field The H.265/HEVC video motion vector steganalysis method that should be selected.
Background technique
Steganography and steganalysis (or Stego-detection) are the important branch of information security field.Digital video is because of it Data volume is big, can accommodate the feature more than secret letter quantity, becomes ideal steganography carrier.It H.265/HEVC is newest Video coding Standard, from prior-generation H.264/AVC in using the macro block of fixed size as coding basic unit it is different, H.265/HEVC allow to adopt With coding unit (Coding Unit, CU) not of uniform size, including 64 × 64,32 × 32,16 × 16 and 8 × 8.To texture compared with Complex region generallys use lesser encoding block, and generallys use biggish encoding block to flat site, this makes Video coding Mode is more flexible, can combine accuracy and code rate.Compared with H.264/AVC standard, under identical visual quality, code stream Length can be reduced half.It has H.265/HEVC gradually applied in the various products of internet, therefore has studied with it as load at present The steganography and steganalysis algorithm of body have important theory significance and practical application value.
Video information steganography is to be inserted into secret letter or be hidden into normal video, therefore can from the angle of information theory At being to add noise to normal video, video distortion is caused to increase, while reducing phase of the video content in time domain and airspace Guan Xing.Specifically, the correlation of adjacent pixel values in same frame is made on airspace to be reduced;And in the time domain, due to time domain The presence of prediction, noise is but also the correlation of adjacent interframe pixel value reduces.Common steganography can substantially be transported from modification These three aspects of transformation coefficient after dynamic vector, prediction mode and quantization are set about, and the present invention is mainly discussed to swear for modification movement The Stego-detection technology of amount.Modifying influence of the motion vector to video can be from prediction residual, weight compressed encoding and correlation three The variation of aspect embodies: secret letter insertion may make motion vector be directed toward other reference blocks, and prediction residual is caused to increase;And The motion vector the modified trend that oriented original motion vector restores after weight compressed encoding;The noise meeting that secret letter insertion introduces Reduce airspace motion vector correlation and time-domain motion vector correlation.Therefore, based on the steganalysis method of motion vector Also mainly related in prediction residual, weight compressed encoding and/or motion vector to embedding close video by comparing not embedding close video Property these three aspects on statistical nature difference, identify that whether there is or not embedding close using the method for pattern classification.In steganalysis most often Pattern classifier includes support vector machines (Support Vector Machine, SVM).
There is Su et al. in 2011 in SIGNAL currently based on the typical steganalysis method of related sexual abnormality Paper " the A Video Steganalytic Algorithm Against Motion- delivered on PROCESSING periodical Vector-Based Steganography ", they think that the insertion of secret letter can change the statistical property of motion vector, and utilize Motion vector histograms central moment extracts feature from time domain and airspace respectively, and finally time domain and spatial feature are connected, and it is final to be formed Characteristic of division vector carry out Classification and Identification as the input of SVM.Lina WANG in 2014 et al. delivers in " electronic letters, vol " Paper " the H.264/AVC video motion vector steganalysis algorithm based on related sexual abnormality " proposes that steganography operation can destroy airspace The correlation of upper adjacent motion vectors, and four-way Motion vector scanning chain is designed according to the characteristics of H.264 predicting piecemeal, it extracts Its symbiosis frequecy characteristic constructs svm classifier feature vector.The deficiency of above two method is not accounting for spatially and temporally to transport Relationship between dynamic vector correlation, the former is only simply connected these two types of features, and airspace fortune is only utilized in the latter Dynamic vector correlative character.Studies have shown that in moving more violent video frame, when airspace motion vector correlation is often better than Domain motion vector correlation;And in moving more slow video frame, time-domain motion vector correlation is typically much stronger than airspace movement Vector correlation.The method of Su et al. spatially and temporally feature will simply be connected, and obvious deficiency is feature vector dimension Increase, computational complexity increases;And the method for Lina WANG et al. has only selected spatial feature, does not make full use of and moves in time domain The exception information of vector.Since H.264/AVC and H.265/HEVC video steganography has certain similitude, the present invention is for upper Deficiency is stated, a kind of steganalysis method adaptively selected towards the space-time characteristic of field of H.265/HEVC video is proposed, it can root According to the content and coding characteristic of video, the feature that reflection motion vector changes in adaptively selected time domain and airspace, construction SVM spy Levy vector.So far, it not yet appears in the newspapers for the adaptively selected steganalysis method of space-time characteristic of field of H.265/HEVC video Road.
Summary of the invention
The purpose of the present invention is in view of the above shortcomings of the prior art, provide one kind adaptively to select based on space-time characteristic of field The H.265/HEVC video motion vector steganalysis method selected.This method being capable of adaptively selected airspace or time-domain motion vector Correlative character composition characteristic vector effectively improves steganalysis verification and measurement ratio in the case where not increasing intrinsic dimensionality, reduces The time of classifier training and classification.
The purpose of the present invention can be achieved through the following technical solutions:
A kind of H.265/HEVC video motion vector steganalysis method adaptively selected based on space-time characteristic of field, it is described Method the following steps are included:
Step 1, by video code flow entropy decoding to compression domain, its coding unit is read for all P frames and predicting unit is drawn Point mode, with position prediction unit, motion vector, motion vector residual error these compressed domains;
Step 2 extracts airspace motion vector correlative character: for each P frame, according to its predicting unit division side Each motion vector is added in the four-way Motion vector scanning chain SS of airspace by formula, in airspace four-way Motion vector scanning chain SS In, the component being utilized respectively on both horizontally and vertically forms two chains, the Pearson correlation coefficient between two chains is calculated, and The direction for selecting Pearson correlation coefficient absolute value small carries out feature extraction, by the party in the four-way Motion vector scanning chain SS of airspace In upward motion vector components deposit feature extraction object MS, and airspace motion vector four-way is obtained as difference to its adjacent position Difference chain DS extracts symbiosis frequecy characteristic to DS to get airspace motion vector correlative character vector CS is arrived;
Step 3 obtains time domain prediction motion vector: it is pre- to obtain its same position in encoded frame to each predicting unit Unit is surveyed, according to current prediction unit at a distance from its reference frame, with position prediction unit at a distance from its reference frame and same position The motion vector computation of predicting unit goes out the time domain prediction motion vector of current prediction unit;
Step 4 extracts time-domain motion vector correlative character: time domain prediction motion vector that step 3 is obtained and current It is poor that motion vector is made, and is stored in time domain four-way Motion vector scanning chain ST according to the division mode of its predicting unit, respectively benefit Two chains are formed with the component on both horizontally and vertically, calculate Pearson correlation coefficient, and select Pearson correlation coefficient exhausted To object of the small direction as feature extraction is worth, component in this direction is stored in time-domain motion vector four-way difference chain DT In, symbiosis frequecy characteristic is extracted to get time-domain motion vector correlative character vector CT to DT;
Step 5, selection candidate video frame: using the motion complexity G of the calculated for pixel values present frame of consecutive frame, for every One G value has a corresponding threshold value λ, using motion vector residual computations spatial correlation integrated value P at that time, if P is greater than threshold Value λ, it is determined that the frame is candidate video frame, and enters step 6, if P is less than or equal to threshold value λ, not as candidate video frame, directly It is its final feature that airspace motion vector correlative character is selected in selecting, and enters step 7;
Step 6 adaptively chooses spatially and temporally motion vector correlative character: for candidate video frame, utilizing movement 0 ratio calculates the size of airspace motion vector correlation and time-domain motion vector correlation in vector four-way difference chain, respectively Ratio shared by calculating 0 in airspace motion vector four-way difference chain and time-domain motion vector four-way difference chain, if airspace movement arrow Amount correlation is stronger, i.e., 0 proportion is higher in airspace motion vector four-way difference chain, then selects airspace motion vector correlation Feature be final feature, if time-domain motion vector correlation is stronger, i.e., in time-domain motion vector four-way difference chain 0 proportion compared with Height then selects time-domain motion vector correlative character for final feature;
The feature input classifier of extraction is trained and is classified by step 7.
Further, in the step 2, construct airspace four-way Motion vector scanning chain, include top edge, lower edge, Four scan chains of left edge and right hand edge, building method are will to be in coding tree unit respectively on the basis of coding tree unit Top edge, lower edge, left edge and right hand edge motion vector be added in order top edge scan chain, lower edge scan chain, In left edge scan chain and right hand edge scan chain, and the scan chain for forming that length is L that joined end to end, due to H.265/HEVC In, the size of each coding tree unit is constant, therefore has one-to-one close between the adjacent motion vectors in same edge System, is not influenced by prediction block sizes, two scannings that the horizontal and vertical component composition length using motion vector is L-1 Chain calculates it Pearson correlation coefficient respectively, and feature is extracted in the direction for selecting Pearson correlation coefficient absolute value small.
Further, in the step 3, H.265/HEVC middle time domain prediction motion vector is not directly by same position prediction list The motion vector of member obtains, but passes through what the flexible adjustment of corresponding ratio obtained, if current prediction unit and reference frame away from It is tb at a distance from its reference frame with position prediction unit, the motion vector with position prediction unit is Col_MV, then currently from for td The time domain prediction motion vector of predicting unit is (Col_MV × td)/tb.
Further, in the step 4, using the method construct time domain four-way Motion vector scanning chain similar with step 2 With calculating Pearson correlation coefficient.
Further, in the step 5, select not embedding close frame for candidate video frame, because in never embedding close video frame The stronger feature of correlation, which is extracted, as final feature can improve classification performance, improve classification accuracy rate, whether judge present frame There are a kind of corresponding relationships: motion complexity for the motion complexity and time-space domain correlation for being the frame for the foundation of candidate video frame Spatial correlation is weaker at that time for higher video frame, and spatial correlation is stronger at that time for the low frame of motion complexity, and embedding close operation It will lead to that time-space domain correlation is obviously reduced but motion complexity is basically unchanged, the method for the invention is to each motion complexity A threshold value is set, the frame that time-space domain correlation integrated value is greater than threshold value is determined as candidate video frame.
Further, it in the step 6, is measured spatially and temporally using in motion vector four-way difference chain 0 ratio Motion vector correlation, since motion vector difference chain is to be obtained by adjacent motion vectors as difference, adjacent motion vectors are equal More, 0 number is more in difference chain, conversely, 0 number is fewer in difference chain.
Compared with the prior art, the invention has the following advantages and beneficial effects:
1, the present invention innovatively mutually ties airspace motion vector correlative character with time-domain motion vector correlative character It closes, can according to video content adaptive select the stronger feature of correlation as final classification feature, two kinds can be made full use of The complementary nature of correlation improves steganalysis verification and measurement ratio.
2, the present invention selects the biggish feature of correlation as final point candidate video frame in time domain and airspace Category feature, the dimension of feature vector and be used only airspace motion vector correlative character or time-domain motion vector correlative character when Unanimously, can be reduced half compared to the concatenated method characteristic dimension of feature, thus this method have lower complicated classification degree and Faster classification speed;
3, H.265/HEVC new motion-vector prediction feature is innovatively used in steganalysis by the present invention, by obtaining The time domain prediction motion vector for taking current prediction unit extracts its time-domain motion vector correlation, when utilization is H.265/HEVC middle Domain motion vector correlation improves the performance of airspace motion vector correlative character than the stronger feature in H.264/AVC;
4, the present invention need to only be carried out in the decoding end of H.265/HEVC standard, without high encoded of complexity Journey has computation complexity low, the fast feature of the speed of service.
Detailed description of the invention
Fig. 1 is a kind of H.265/HEVC video motion vector adaptively selected based on space-time characteristic of field of the embodiment of the present invention The flow diagram of steganalysis method.
Fig. 2 (a) is structurally boundary scan chain schematic diagram of the embodiment of the present invention, and Fig. 2 (b) is that construction lower edge scan chain shows It is intended to, Fig. 2 (c) is construction left edge scan chain schematic diagram, and Fig. 2 (d) is construction right hand edge scan chain schematic diagram.
Fig. 3 is H.265/HEVC time domain prediction motion vector schematic diagram of the embodiment of the present invention.
Fig. 4 is the ROC curve figure of classification results in the embodiment of the present invention.
Specific embodiment
Present invention will now be described in further detail with reference to the embodiments and the accompanying drawings, but embodiments of the present invention are unlimited In this.
Embodiment:
It is hidden to present embodiments provide a kind of H.265/HEVC video motion vector adaptively selected based on space-time characteristic of field Analysis method is write, flow diagram is as shown in Figure 1, be broadly divided into seven steps, including decoding video extracts compressed domain, extracts Airspace motion vector correlative character obtains time domain prediction motion vector, extracts relativity of time domain feature, chooses candidate video Frame, adaptively selected airspace or time-domain motion vector correlative character are as final classification feature, trained and Classification and Identification.Below Implementation process of the invention is discussed in detail as embodiment using the video library that 10 CIF videos form.It is used in embodiment H.265/HEVC as decoder, carrying close video can be passed through with certain insertion official's test model HM-13.0 by original video The typical steganography of amount operates to obtain, and the present embodiment is using Aly et al. in IEEE Transactions on Information Classic paper " the Data Hiding in Motion Vectors of delivered on Forensics and Security periodical Method in Compressed Video Based On Their Associated Prediction Error " is full to make The close sample of embedding load.
The first step, decoding video extract compressed domain.
The main purpose of decoding video code stream is that necessary parameter, such as prediction block division side are provided for subsequent steganalysis The information such as formula, motion vector, motion vector residual error.By taking above-mentioned CIF video as an example, by video binary code stream entropy decoding to compression Domain obtains the division mode of each coding unit in each P frame, predicting unit, obtains four-way Motion vector scanning for second step Chain provides judgment basis.In H.265/HEVC, each coding tree unit has a motion-vector field m_acCUMvField, Motion vector all in the coding tree unit is contained, we can be inclined in coding tree unit according to each predicting unit Shifting amount obtains motion vector.
Second step extracts airspace motion vector correlative character.
Due to predicting unit division mode multiplicity in H.265/HEVC and not of uniform size, motion vector may be There are multiple adjacent motion vectors in same direction, causes correlation extraction difficult.The present embodiment is swept using four-way motion vector The method of chain is retouched to describe the neighborhood relationships of motion vector.H.264/AVC the basic unit encoded in is macro block, and H.265/ It is coding unit that basic unit is encoded in HEVC.Different from H.264/AVC middle macroblock size fixation, H.265/HEVC middle coding is single Member size be it is variable, can divide to obtain by the coding tree unit of fixed size, thus this method with coding tree unit and Non-coding unit is benchmark tectonic movement vector scan chain.Since each coding tree unit size is constant, it is in same one side There is one-to-one relationship between the adjacent motion vectors of edge, do not influenced by prediction block sizes.Such as Fig. 2 (a), Fig. 2 (b), Fig. 2 (c) and shown in Fig. 2 (d), the square that heavy line surrounds is a coding tree unit, and the square that fine line surrounds is a volume Code unit, the rectangle that dotted line surrounds are a predicting unit, and this method will be in coding tree unit top edge and lower edge respectively Prediction block, i.e. Fig. 2 (a) are added to top edge scan chain by sequence from left to right with the motion vector in shaded block in Fig. 2 (b) In lower edge scan chain, coding tree unit left edge and right hand edge prediction block, i.e. shade in Fig. 2 (c) and Fig. 2 (d) will be in Motion vector in block is added in left edge scan chain and right hand edge scan chain by sequence from top to bottom, to guarantee each Motion vector simplifies the extraction of correlation with a uniqueness for direction neighborhood.
By the scan chain of four direction by top edge scan chain, lower edge scan chain, left edge scan chain, right hand edge scanning The sequence of chain joins end to end, and obtaining the Motion vector scanning chain SS that length is L, (all motion vector horizontal components are constituted in note SS Collection be combined into SSx, the collection that all motion vector vertical components are constituted is combined into SSy), and it is divided into i=1 to L-1 and i=2 is arrived Two groups of motion vector set of L (i is the position in SS), are utilized respectively motion vector vertical direction and horizontal direction component calculate this The Pearson correlation coefficient of two groups of motion vector set:
Wherein, rxAnd ryThe Pearson correlation coefficient of motion vector horizontal and vertical direction is respectively indicated, value range is [-1,1]。SSx,iAnd SSx,i+1Respectively indicate i-th and i+1 motion vector horizontal durection component, SS in SSy,iAnd SSy,i+1 I-th and i+1 motion vector vertical durection component in SS are respectively indicated,WithRespectively such as following formula Definition:
The present embodiment carries out feature extraction to the lesser direction of Pearson correlation coefficient absolute value, because of fortune in this direction Dynamic vector component correlations are poor, and steganography is more serious to its related damage.It chooses motion vector direction and generates subsequent characteristics The rule for extracting object MS is as follows:
It is poor to make to each adjacent motion vectors component in MS, obtains airspace motion vector four-way difference chain DS, it may be assumed that
DSi=MSi-MSi+1 (8)
Symbiosis frequecy characteristic is extracted to motion vector four-way difference chain, i.e., to two in DS at a distance of the motion vector point for l Amount calculates its joint probability for being respectively equal to n and m:
Wherein n and m takes the integer in [- 2,2], and l takes 1 or 2.Combined according to each exploitation of the above formula to n, m and l general Rate, and be successively added in the motion vector correlative character vector CS of airspace.
Third step obtains time domain prediction motion vector.
For each predicting unit in present frame, time domain predicted motion vector can be sweared by the movement of same position prediction unit Amount, with position prediction unit at a distance from its reference frame and the distance between present frame and reference frame are scaled to obtain.Because H.265/HEVC the thought of object uniform motion is mainly utilized in the time domain prediction of middle motion vector, if it is determined that is separated by certain The motion vector of the two field pictures of distance, then between this two frame any one frame predicted motion vector can by the frame to this two A distance with reference to interframe is calculated.As shown in H.265/HEVC time domain prediction motion vector schematic diagram in Fig. 3, this method is logical The same position prediction unit Col_PU for obtaining current prediction unit is crossed, and according to Col_PU and its reference frame distance tb, Col_PU Corresponding motion vector Col_MV and current prediction unit and reference frame distance td calculates time domain prediction fortune by following formula Dynamic vector:
4th step extracts relativity of time domain feature.
It is for the time domain prediction motion vector of acquisition, it is poor with current motion vector work, and according to method shown in Fig. 2 It is deposited into time domain four-way Motion vector scanning chain ST and (remembers that the collection of all motion vector horizontal components compositions in ST is combined into STx, The collection that all motion vector vertical components are constituted is combined into STy), then it is utilized respectively the horizontal and vertical component institute group of motion vector At two chains, according to formula (1) (2) calculate Pearson correlation coefficient, be denoted as rtxAnd rty.Select Pearson correlation coefficient exhausted To object of the lesser direction as feature extraction is worth, motion vector components in this direction are stored in time-domain motion vector four-way In difference chain DT, it may be assumed that
To time-domain motion vector four-way difference chain DT, time domain symbiosis frequecy characteristic is extracted according to formula (9), obtains time domain phase Closing property feature vector CT.
5th step chooses candidate video frame.
The purpose that the present embodiment chooses candidate video frame is and to make its correlation high for the not embedding close video frame of determination Feature is as final classification feature.Some not embedding close video frames airspace motion vector correlation itself is not strong, may be with the close view of load Frequency frame is very nearly the same, and this frame easilys lead to classification error, to reduce overall verification and measurement ratio.And time-domain motion vector is related Property and airspace motion vector correlation often have complementarity, and airspace motion vector correlation is better than in the video of motion intense Time-domain motion vector correlation, in moving slow video, it is related that time-domain motion vector correlation is better than airspace motion vector Property, therefore overall classification performance can be improved by selecting the feature of high correlation for not embedding close video frame, but answer Avoid carrying the influence of close video frame as far as possible, because identification can be reduced instead to the feature for carrying close video frame selection high correlation Rate.
For each P frame, its motion complexity is sought by the pixel value on consecutive frame:
Wherein, k is k-th of P frame, and M and N are the width and height of video frame, in the present embodiment respectively 352 and 288. fk(i, j) and fk-1(i, j) respectively indicates the pixel value of kth frame and -1 frame of kth at the position (i, j).The G (k) the big, represents view The movement of frequency frame is more violent, on the contrary then to represent video frame motion gentler.
For each P frame, spatial correlation integrated value at that time is measured by calculating the reciprocal of motion vector residual error mean value:
Wherein avgMVD (i) is the mean value of motion vector residual values in i-th of coding tree unit.CTUNum is institute in P frame There is the quantity of coding tree unit, is in the present embodiment 30.The average MVD length of each coding tree unit is sought in formula (13) It is expressed from the next:
Wherein, CTUWidth and CTUHeight respectively indicates the width and height of coding tree unit, in the present embodiment all The width of j-th of predicting unit in i-th of coding tree unit is respectively indicated for 64, PUWidth (i, j) and PUHeight (i, j) And height, MVD (i, j) indicate j-th of motion vector residual values in i-th of coding tree unit, including xijAnd yijTwo components, Its length calculation method is as follows:
After the motion complexity G and time-space domain correlation integrated value P that calculate present frame, if complicated movement angle value be greater than etc. In 4, then it is assumed that movement is more violent, and relativity of time domain is very poor, does not have referential substantially, directly takes airspace motion vector related Property feature be final classification feature, otherwise P is compared with the threshold value λ in formula (16), if P, greater than threshold value λ, which is Candidate video frame simultaneously enters the 6th step, if P is less than or equal to threshold value λ, which directly takes airspace to move not as candidate video frame Vector correlation feature is final classification feature.
6th step, adaptively selected airspace or time-domain motion vector correlative character are as final classification feature.
For selected candidate video frame, the frame is sought by calculating in its motion vector four-way difference chain 0 ratio Spatially and temporally motion vector correlation:
Wherein zeronumSAnd zeronumTRespectively spatially and temporally in motion vector four-way difference chain 0 quantity, Length (DS) and Length (DT) is respectively the total length of spatially and temporally motion vector four-way difference chain.
If RS>=RT, then select airspace motion vector correlative character as final classification feature, if RS<RT, then select Time-domain motion vector correlative character is as final classification feature.
7th step, trained and Classification and Identification.
The final feature of acquisition input classifier is trained and Classification and Identification.The present embodiment makees 50% video frame For training sample, in addition 50% video frame is trained and is classified using LIB-SVM as test sample, obtains true positive rate (carrying all P frames in close video to be detected as carrying the ratio of close video) is 91.165%, and true negative rate (does not carry in close video and owns P frame is detected as not carrying the ratio of close video) it is 92.272%.In the present embodiment, the ROC curves of classification results as shown in figure 4, It can be seen that ROC curve is close to the upper left corner, there is preferable classification performance, it was demonstrated that effectiveness of the invention.
The above, only the invention patent preferred embodiment, but the scope of protection of the patent of the present invention is not limited to This, anyone skilled in the art is in the range disclosed in the invention patent, according to the present invention the skill of patent Art scheme and its patent of invention design are subject to equivalent substitution or change, belong to the scope of protection of the patent of the present invention.

Claims (6)

1. a kind of H.265/HEVC video motion vector steganalysis method adaptively selected based on space-time characteristic of field, feature It is, the described method comprises the following steps:
Step 1, by video code flow entropy decoding to compression domain, its coding unit and predicting unit division side are read for all P frames Formula, with position prediction unit, motion vector, motion vector residual error these compressed domains;
Step 2 extracts airspace motion vector correlative character: will according to its predicting unit division mode for each P frame Each motion vector is added in the four-way Motion vector scanning chain SS of airspace, in the four-way Motion vector scanning chain SS of airspace, point Not Li Yong both horizontally and vertically on component form two chains, calculate the Pearson correlation coefficient between two chains, and select The small direction of Pearson correlation coefficient absolute value carries out feature extraction, by the four-way Motion vector scanning chain SS of airspace in this direction Motion vector components deposit feature extraction object MS in, and airspace motion vector four-way difference is obtained as difference to its adjacent position Chain DS extracts symbiosis frequecy characteristic to DS to get airspace motion vector correlative character vector CS is arrived;
Step 3 obtains time domain prediction motion vector: obtaining its same position prediction list in encoded frame to each predicting unit Member, according to current prediction unit at a distance from its reference frame, with position prediction unit at a distance from its reference frame and same position prediction The motion vector computation of unit goes out the time domain prediction motion vector of current prediction unit;
Step 4 extracts time-domain motion vector correlative character: the time domain prediction motion vector and current kinetic that step 3 is obtained It is poor that vector is made, and is stored in time domain four-way Motion vector scanning chain ST according to the division mode of its predicting unit, is utilized respectively water Component in gentle vertical direction forms two chains, calculates Pearson correlation coefficient, and select Pearson correlation coefficient absolute value Component in this direction is stored in time-domain motion vector four-way difference chain DT by object of the small direction as feature extraction, right DT extracts symbiosis frequecy characteristic to get time-domain motion vector correlative character vector CT;
Step 5, selection candidate video frame: using the motion complexity G of the calculated for pixel values present frame of consecutive frame, for each G value has a corresponding threshold value λ, using motion vector residual computations spatial correlation integrated value P at that time, if P is greater than threshold value λ, It then determines that the frame is candidate video frame, and enters step 6, if P is less than or equal to threshold value λ, not as candidate video frame, directly select Selecting airspace motion vector correlative character is its final feature, and enters step 7;
Step 6 adaptively chooses spatially and temporally motion vector correlative character: for candidate video frame, utilizing motion vector 0 ratio calculates the size of airspace motion vector correlation and time-domain motion vector correlation in four-way difference chain, calculates separately Ratio shared by 0 in airspace motion vector four-way difference chain and time-domain motion vector four-way difference chain, if airspace motion vector phase Closing property is stronger, i.e., 0 proportion is higher in airspace motion vector four-way difference chain, then selects airspace motion vector correlative character For final feature, if time-domain motion vector correlation is stronger, i.e., 0 proportion is higher in time-domain motion vector four-way difference chain, Then select time-domain motion vector correlative character for final feature;
The feature input classifier of extraction is trained and is classified by step 7.
2. a kind of H.265/HEVC video motion vector adaptively selected based on space-time characteristic of field according to claim 1 Steganalysis method, it is characterised in that: in the step 2, construct airspace four-way Motion vector scanning chain, include top edge, Four lower edge, left edge and right hand edge scan chains, building method are will to be in coding respectively on the basis of coding tree unit It sets unit top edge, lower edge, left edge and the motion vector of right hand edge is added to top edge scan chain in order, lower edge is swept It retouches in chain, left edge scan chain and right hand edge scan chain, and the scan chain for forming that length is L that joined end to end, due to H.265/HEVC in, the size of each coding tree unit is constant, therefore has one between the adjacent motion vectors in same edge One-to-one correspondence is not influenced by prediction block sizes, is L-1's using the horizontal and vertical component composition length of motion vector Two scan chains calculate it Pearson correlation coefficient respectively, and the direction for selecting Pearson correlation coefficient absolute value small is extracted special Sign.
3. a kind of H.265/HEVC video motion vector adaptively selected based on space-time characteristic of field according to claim 1 Steganalysis method, it is characterised in that: in the step 3, H.265/HEVC middle time domain prediction motion vector is not directly by same The motion vector of position prediction unit obtains, but passes through what the flexible adjustment of corresponding ratio obtained, if current prediction unit and ginseng The distance for examining frame is td, is tb at a distance from its reference frame with position prediction unit, and the motion vector with position prediction unit is Col_ MV, then the time domain prediction motion vector of current prediction unit is (Col_MV × td)/tb.
4. a kind of H.265/HEVC video motion vector adaptively selected based on space-time characteristic of field according to claim 2 Steganalysis method, it is characterised in that: in the step 4, using the method construct time domain four-way motion vector similar with step 2 Scan chain and calculating Pearson correlation coefficient.
5. a kind of H.265/HEVC video motion vector adaptively selected based on space-time characteristic of field according to claim 1 Steganalysis method, it is characterised in that: in the step 5, select not embedding close frame for candidate video frame, because of never embedding close view The stronger feature of correlation is extracted in frequency frame as final feature can improve classification performance, improve classification accuracy rate, and judgement is current Frame whether be candidate video frame foundation be the frame motion complexity and time-space domain correlation there are a kind of corresponding relationships: movement Spatial correlation is weaker at that time for the higher video frame of complexity, and spatial correlation is stronger at that time for the low frame of motion complexity, and embedding Close operation will lead to that time-space domain correlation is obviously reduced but motion complexity is basically unchanged, and the method for the invention is to each movement Complexity sets a threshold value, and the frame that time-space domain correlation integrated value is greater than threshold value is determined as candidate video frame.
6. a kind of H.265/HEVC video motion vector adaptively selected based on space-time characteristic of field according to claim 1 Steganalysis method, it is characterised in that: in the step 6, measure airspace using in motion vector four-way difference chain 0 ratio With time-domain motion vector correlation, since motion vector difference chain is to be obtained by adjacent motion vectors as difference, adjacent motion vectors Equal is more, and 0 number is more in difference chain, conversely, 0 number is fewer in difference chain.
CN201710145997.3A 2017-03-13 2017-03-13 A kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field Expired - Fee Related CN107040786B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201710145997.3A CN107040786B (en) 2017-03-13 2017-03-13 A kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201710145997.3A CN107040786B (en) 2017-03-13 2017-03-13 A kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field

Publications (2)

Publication Number Publication Date
CN107040786A CN107040786A (en) 2017-08-11
CN107040786B true CN107040786B (en) 2019-06-18

Family

ID=59534447

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201710145997.3A Expired - Fee Related CN107040786B (en) 2017-03-13 2017-03-13 A kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field

Country Status (1)

Country Link
CN (1) CN107040786B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109982071B (en) * 2019-03-16 2020-08-11 四川大学 HEVC (high efficiency video coding) dual-compression video detection method based on space-time complexity measurement and local prediction residual distribution
CN112135137B (en) * 2019-06-25 2024-04-09 华为技术有限公司 Video encoder, video decoder and corresponding methods
CN111462765B (en) * 2020-04-02 2023-08-01 宁波大学 Adaptive audio complexity characterization method based on one-dimensional convolution kernel
WO2023130285A1 (en) * 2022-01-05 2023-07-13 Oppo广东移动通信有限公司 Method, apparatus and system for predicting temporal motion information, and method, apparatus and system for constructing candidate list

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104519361A (en) * 2014-12-12 2015-04-15 天津大学 Video steganography analysis method based on space-time domain local binary pattern
CN106131553A (en) * 2016-07-04 2016-11-16 武汉大学 A kind of video steganalysis method based on motion vector residual error dependency

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010108024A1 (en) * 2009-03-20 2010-09-23 Digimarc Coporation Improvements to 3d data representation, conveyance, and use

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104519361A (en) * 2014-12-12 2015-04-15 天津大学 Video steganography analysis method based on space-time domain local binary pattern
CN106131553A (en) * 2016-07-04 2016-11-16 武汉大学 A kind of video steganalysis method based on motion vector residual error dependency

Also Published As

Publication number Publication date
CN107040786A (en) 2017-08-11

Similar Documents

Publication Publication Date Title
CN107040786B (en) A kind of H.265/HEVC video steganalysis method adaptively selected based on space-time characteristic of field
Cao et al. Video steganalysis exploiting motion vector reversion-based features
CN105933711B (en) Neighborhood optimum probability video steganalysis method and system based on segmentation
CN101478691B (en) Non-reference evaluation method for Motion Jpeg2000 video objective quality
CN104199627B (en) Gradable video encoding system based on multiple dimensioned online dictionary learning
CN107079165A (en) Use the method for video coding and device of prediction residual
CN107197297A (en) A kind of video steganalysis method of the detection based on DCT coefficient steganography
CN103152578A (en) H.264 video watermark embedding and extraction method based on mixed coding/decoding
CN102496165A (en) Method for comprehensively processing video based on motion detection and feature extraction
CN109819260A (en) Video steganography method and device based on the fusion of multi-embedding domain
CN105657431A (en) Watermarking algorithm based on DCT domain of video frame
CN104853215B (en) The video steganography method kept based on motion vector local optimality
CN105979269A (en) Motion vector domain video steganography method based on novel embedding cost
CN104853186A (en) Improved video steganalysis method based on motion vector reply
CN101765011B (en) Method and device for scaling motion estimation
Hu et al. Optimized spatial recurrent network for intra prediction in video coding
CN105915916B (en) Video steganalysis method based on the estimation of motion vector distortion performance
CN108171325A (en) Sequential integrated network, code device and the decoding apparatus that a kind of multiple dimensioned face restores
CN101389032A (en) Intra-frame predictive encoding method based on image value interposing
CN105721875B (en) A kind of video motion vector Stego-detection method based on entropy
CN107895355B (en) Motion detection and image contrast self-adaptive enhancement system and method
CN110324634A (en) It is a kind of to be embedded in the video steganography method that distortion is decomposed based on motion vector
Qin et al. An improved method of image denoising based on wavelet transform
CN106101713B (en) A kind of video steganalysis method based on the optimal calibration of window
CN107888931A (en) A kind of method using video statistics feature prediction error susceptibility

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20190618