Video privacy protection method, video playing method and related devices

Abstract

The invention provides a video privacy protection method, a video playing method and related devices. The video privacy protection method comprises the following steps: acquiring an original encryption parameter and an original video; for each original video frame, determining a privacy area of the original video frame, and performing image blurring processing on the privacy area of the original video frame by adopting a preset blurring algorithm to obtain a blurred video frame; taking the fuzzy video frame as input data of a base layer in a target encoder, taking the original video frame as input data of an enhancement layer in the target encoder, and performing video encoding by adopting the target encoder to obtain first video encoding data; encrypting enhanced data in the first video coding data according to the original encryption parameter to obtain second video coding data; and generating the privacy protection video based on the second video coding data. According to the method, the expandability of the H.265 coding technology and the password technology are combined, and the two aspects of high efficiency and reversible reduction can be considered at the same time.

Description

Technical Field

[0001] The present application relates to the field of information security technology, and in particular to a video privacy protection method, a video playback method and related devices. Background Art

[0002] The widespread use of video surveillance systems has brought security and convenience to public places (such as stations, shopping malls, streets, etc.) and home scenes. In order to support live viewing of surveillance videos and AI (Artificial Intelligence) analysis applications, surveillance videos collected by video surveillance systems are usually uploaded to cloud servers for video storage and video calls through cloud servers. However, with the gradual increase in data security requirements and privacy protection requirements, how to ensure the privacy security of videos has become one of the focuses of attention.

[0003] At present, existing technologies mainly provide video privacy protection in the following ways:

[0004] (1) Encrypting the video file as a whole, but this makes it impossible to conduct AI analysis and application on the ciphertext data file, which greatly affects the release of the video's value. At the same time, the video file needs to be completely decrypted before playing, and the decrypted video no longer has the privacy protection function. This "all or nothing" encryption is not suitable for the actual needs of both playback and privacy protection.

[0005] (2) Locally encrypt the privacy area in the video, that is, only encrypt the specified privacy area in the video, and the rest of the area is visible during playback. Although this method can present the visual effect of privacy protection during video playback, it requires accurate recording of the coordinates of the privacy area of ​​each video frame, and the encryption algorithm needs to be organically integrated with the entropy coding algorithm in video encoding, so you can only selectively encrypt some coding elements. At the same time, due to the complexity of the entropy coding algorithm and the difficulty of algorithm integration, this implementation method has the disadvantages of low encryption efficiency and low flexibility.

[0006] (3) Perform privacy anonymization processing on the video, that is, using blur algorithms such as Gaussian blur, pixelation, and mosaic to make the image content corresponding to the privacy area in the video unrecognizable, thereby achieving privacy protection. However, video privacy protection processing modes such as Gaussian blur and mosaic will cause the loss of image information, resulting in the inability of playback devices to accurately restore the original video from the encrypted video.

[0007] (4) Generative adversarial networks are used to replace the image content corresponding to the private area in the video, so as not to leak the real information of the original video. Compared with the mosaic algorithm, the method of using generative adversarial networks to replace image content has better visual acceptance, but in terms of video restoration, even if key content features are additionally saved, it still cannot support accurate restoration.

[0008] This shows that the existing video privacy protection scheme cannot take into account both high efficiency and reversible restoration. Summary of the invention

[0009] The purpose of the present application is to solve at least one of the above-mentioned technical defects, especially the technical defect that the prior art cannot take into account both high efficiency and reversible reduction.

[0010] In a first aspect, an embodiment of the present application provides a video privacy protection method, which is applied to a video encryption device, comprising:

[0011] Obtaining original encryption parameters and original video; wherein the original video includes multiple original video frames;

[0012] For each of the original video frames, determine the privacy area of ​​the original video frame, and use a preset blur algorithm to perform image blurring processing on the privacy area of ​​the original video frame to obtain a blurred video frame;

[0013] Using the blurred video frame as input data of a base layer in a target encoder, using the original video frame as input data of an enhancement layer in the target encoder, using the target encoder to perform video encoding, and obtaining first video encoding data; wherein the target encoder is an encoder supporting H.265 scalable encoding;

[0014] Encrypting the enhanced data in the first video encoding data according to the original encryption parameter to obtain second video encoding data; wherein the enhanced data is data output by the enhancement layer;

[0015] Generate a privacy-preserving video based on the second video encoding data.

[0016] In some embodiments, encrypting the enhanced data in the first video encoding data according to the original encryption parameter includes:

[0017] Determine a unit identifier corresponding to the target NAL unit data; wherein the target NAL unit data is any first NAL unit data included in the enhanced data, and the unit identifier is used to uniquely identify the first NAL unit data;

[0018] Generate target encryption parameters according to the unit identifier and the original encryption parameters;

[0019] The payload data of the target NAL unit data is encrypted according to the target encryption parameters.

[0020] In some embodiments, the original encryption parameters include an original initialization vector and an original encryption key, and the target encryption parameters include a target initialization vector and a target encryption key;

[0021] The step of generating a target encryption parameter according to the unit identifier and the original encryption parameter comprises:

[0022] Using a preset hash algorithm, performing a hash calculation on the unit identifier, the original initialization vector, and the original encryption key to obtain a target hash value;

[0023] According to a preset division rule, the target Hash value is divided into the target initialization vector and the target encryption key.

[0024] In some embodiments, encrypting the payload data of the target NAL unit data according to the target encryption parameter includes:

[0025] According to the target encryption parameters, the SM4-CTR mode encryption algorithm is used to encrypt the payload data of the target NAL unit data.

[0026] In some embodiments, the enhancement data in the second video encoding data includes at least one SEI data and at least one second NAL unit data, and the second NAL unit data includes a type identification value;

[0027] The step of generating a privacy-preserving video based on the second video encoding data includes:

[0028] For each of the second NAL unit data, the type identification value of the second NAL unit data is written into the corresponding SEI data, and the type identification value of the second NAL unit data is modified to an undefined identification value.

[0029] In some embodiments, the original encryption parameters include an original initialization vector and an original encryption key;

[0030] The step of generating a privacy-preserving video based on the second video encoding data further includes:

[0031] Encrypting the original encryption key using a preset password information to obtain a ciphertext key;

[0032] The ciphertext key and the original initialization vector are written into the first SEI data of the second video encoding data.

[0033] In a second aspect, an embodiment of the present application provides a video playback method, which is applied to a video playback device, including:

[0034] Obtaining a privacy-preserving video; wherein the privacy-preserving video is generated by the video privacy protection method described in any of the above embodiments;

[0035] Obtaining original encryption parameters corresponding to the privacy-preserving video;

[0036] The enhanced data in the privacy-preserving video is decrypted according to the original encryption parameters, and the original video is obtained based on the decryption result.

[0037] In a third aspect, an embodiment of the present application provides a video privacy protection device, which is applied to a video encryption device, including:

[0038] An original data acquisition module, used to acquire original encryption parameters and original video; wherein the original video includes a plurality of original video frames;

[0039] A blur processing module, for determining the privacy area of ​​each original video frame, and performing image blur processing on the privacy area of ​​the original video frame using a preset blur algorithm to obtain a blurred video frame;

[0040] A video encoding module, configured to use the blurred video frame as input data of a base layer in a target encoder, use the original video frame as input data of an enhancement layer in the target encoder, use the target encoder to perform video encoding, and obtain first video encoding data; wherein the target encoder is an encoder supporting H.265 scalable encoding;

[0041] A video encryption module, used for encrypting the enhanced data in the first video encoding data according to the original encryption parameter to obtain second video encoding data; wherein the enhanced data is data output by the enhancement layer;

[0042] A privacy protection module is used to generate a privacy protection video based on the second video encoding data.

[0043] In a fourth aspect, an embodiment of the present application provides a video playback device, which is applied to a video playback device, including:

[0044] A video acquisition module, used to acquire a privacy-preserving video; wherein the privacy-preserving video is generated based on the video privacy protection method described in any of the above embodiments;

[0045] An encryption parameter acquisition module, used to obtain the original encryption parameters corresponding to the privacy protection video;

[0046] A decryption module is used to decrypt the enhanced data in the privacy protection video according to the original encryption parameters, and obtain the original video based on the decryption result.

[0047] In a fifth aspect, an embodiment of the present application provides a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the video privacy protection method described in any of the above embodiments, and / or execute the steps of the video playback method described in any of the above embodiments.

[0048] In the video privacy protection method, video playback method and related devices provided in some embodiments of the present application, the video encryption device can use any blur algorithm to perform image blurring on the privacy area of ​​the original video frame to obtain a blurred video frame that can protect privacy information, thereby improving the flexibility of video privacy protection. The video encryption device uses the scalable capability of the H.265 encoding technology to encode the blurred video frame through the base layer of the target encoder, and encode the original video frame through the enhancement layer of the target encoder. Since the scalable coding uses inter-layer predictive coding optimization technology, that is, the enhancement layer only stores additional information that is different from the base layer, the efficiency of blurring and encoding can be improved, thereby realizing an efficient video privacy protection solution.

[0049] In addition, the video encryption device can encrypt the enhanced data output by the enhancement layer, and generate a privacy-protected video based on the second video encoding data obtained by the encryption process. In this way, without knowing the encryption parameters, the user cannot know the plaintext data of the enhanced data, so he can only view the blurred video frames with privacy protection effects but cannot view the original clear video. For users who can obtain the encryption parameters, they can use the reciprocity of encryption and decryption to decrypt, so as to obtain the plaintext data of the enhanced data, and then accurately decrypt and restore the original video, realizing reversible restoration.

[0050] It can be seen that the present application utilizes the scalability of H.265 encoding technology to achieve flexible and efficient video privacy protection, and combines the encryption and decryption reciprocity of cryptographic technology to achieve reversible restoration function, thereby taking into account both high efficiency and reversible restoration. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0052] Figure 1FIG. 1 is an application environment diagram of a video privacy protection method and a video playback method in one embodiment;

[0053] Figure 2 A schematic diagram of a frame of an original video frame in one embodiment;

[0054] Figure 3 A schematic diagram of a frame image processed by an AI recognition algorithm in one embodiment;

[0055] Figure 4 A schematic diagram of an encrypted frame image in one embodiment;

[0056] Figure 5 A schematic diagram of a decrypted frame image in one embodiment;

[0057] Figure 6 A schematic diagram of a process of a video privacy protection method in one embodiment;

[0058] Figure 7 A schematic diagram of a flow chart of a video playback method in one embodiment;

[0059] Figure 8 is a structural schematic diagram of a video privacy protection device in one embodiment;

[0060] Fig. 9 is a schematic structural diagram of a video playback device in one embodiment;

[0061] Fig.10 FIG. 1 is a diagram of the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0062] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0063] The terms involved in this application are explained below.

[0064] HEVC (High Efficiency Video Coding): High-efficiency video coding, also known as H.265 coding.

[0065] SHVC (Scalable HEVC): HEVC / H.265 scalable coding.

[0066] BL (Base Layer): The base layer of SHVC encoding.

[0067] EL (Enhancement Layer): Enhancement layer of SHVC encoding.

[0068] ROP (Region of Privacy): Privacy area.

[0069] YOLO (You Only Look Once): A deep learning object detection model.

[0070] IV (Initialization Vector): Initialization vector of the block encryption algorithm.

[0071] CTR (Counter): Counter mode of block cipher algorithm.

[0072] AI (Artificial Intelligence): Artificial Intelligence.

[0073] SEI (Supplemental Enhancement Information): Supplemental enhancement information.

[0074] NAL (Network Abstraction Layer): Network abstraction layer for video.

[0075] In some embodiments, the present application provides a video privacy protection method and a video playback method that can be applied to Figure 1 In the application environment shown. Among them, the acquisition device refers to a video acquisition device, which can be installed in public and / or private places in a legal and compliant manner to collect original videos. For example, the acquisition device may be a surveillance camera. It should be noted that the image / video acquisition, storage, use, processing, transmission, provision and disclosure involved in this application are in compliance with the provisions of relevant laws and regulations and do not violate public order and good customs.

[0076] A video encryption device refers to a device used to encrypt an original video to generate a privacy-protected video. A video playback device refers to a device used to decrypt a privacy-protected video to obtain the original video and play it. The cloud storage function can be implemented through a cloud server, that is, the privacy-protected video can be uploaded to a cloud server for storage.

[0077] It is understood that the video encryption device and the video playback device can be implemented by any device, and this document does not impose specific restrictions on this. In one example, the video encryption device and the video playback device can be a local computing device or a computing device that has been security-certified. In another example, the video encryption device and the acquisition device can be integrated into one, and the integrated acquisition device can have a video acquisition function and a video encryption function. In another example, the video playback device can be an electronic terminal that has been authorized and authenticated.

[0078] See also Figure 1 Some embodiments of the present application make comprehensive use of H.265 scalable coding, AI recognition model and cryptographic technology to provide a more flexible and efficient video privacy protection method and video playback method. The video privacy protection method may include steps such as video privacy area identification, privacy area protection and data encryption, and forming a privacy protection video. The video playback method may include steps such as using a key to decrypt and restore.

[0079] Specifically, the acquisition device can acquire the original video and obtain the video file of the original video. The original video includes one or more original video frames, and at least one original video frame includes privacy information. The video encryption device can use an AI recognition algorithm to automatically identify the privacy area of ​​each original video frame, and use a blur algorithm such as a Gaussian blur algorithm to perform privacy protection processing on the privacy area of ​​the original video frame to obtain a blurred video frame. In one example, the original video frame can be as follows: Figure 2 As shown, the privacy area identified by AI can be Figure 3 As shown in the rectangular box, the blurred video frame can be Figure 4 shown.

[0080] When each blurred video frame is obtained, the video encryption device can use a target encoder that supports H.265 scalable coding to encode the privacy-protected image frame (i.e., blurred video frame) into a base layer data unit, encode the original clear version of the video image frame (i.e., original video frame) into an enhancement layer data unit, and obtain a plaintext version of the scalable coded video file (i.e., the first video coded data). For the enhanced data output by the enhancement layer, the video encryption device can use the original encryption parameters to encrypt the NAL unit data corresponding to the enhanced data, and record the original encryption parameters to form the final privacy-protected video. The video encryption device can upload the video coded data corresponding to the privacy-protected video to the cloud server for cloud storage through the cloud server.

[0081] Without knowing the encryption parameters, the video playback effect corresponding to the privacy-protected video can be as follows: Figure 4As shown, a blurred visual effect is presented. It can be seen that this application can effectively protect privacy and is applicable to surveillance video privacy protection in public and private places. Even if the video is stored in the cloud, the cloud storage administrator or illegal attacker can only see the privacy-protected video.

[0082] With the encryption parameters, the video playback device can use the encryption parameters to decrypt the correct enhancement layer data and play the video based on the decrypted data. After decryption, the video presents the original clear visual effect, such as Figure 5 Further, in some examples, when playing online, the video playback device can achieve decrypted playback by playing while decrypting. In other examples, when playing offline, the video playback device can play after completely decrypting the video into plain text.

[0083] It should be noted that Figure 2 , Figure 3 and Figure 5 The blurring of the face area is to meet the relevant provisions of patent examination. Figure 2 The original video frame shown, Figure 3 The privacy region identification results and Figure 5 The decoded video frames shown are all clear image frames that have not been blurred, thereby providing a technical solution for video viewing by legally authorized persons or legal electronic evidence collection.

[0084] It can be seen that the solutions provided by some embodiments of the present application have at least one of the following advantages:

[0085] (1) It can effectively protect privacy and is suitable for surveillance video privacy protection in public and private places. Even if the video is stored in the cloud, the cloud storage administrator or attacker can only see the privacy-protected video. Only the key owner can decrypt and watch the original clear video.

[0086] (2) It has great flexibility in ROP specification of privacy areas and privacy protection processing. First, ROP can flexibly provide privacy areas that need to be protected based on AI or manual selection. Secondly, the processing of base layer privacy areas is not limited to Gaussian blur, and privacy area anonymization technologies such as pixel blur, ROP encryption, and generative adversarial networks can also be used. The method provided in this application does not need to accurately record the coordinates of the ROP area, because this application essentially uses the enhancement layer data to save the clear version of the video frame data.

[0087] (3) It has a secure and efficient privacy protection encryption capability. This application is to encrypt the enhanced layer data unit after scalable coding. The encryption algorithm can adopt a secure national secret block encryption algorithm. The cloud storage administrator or attacker without the key cannot restore the original video. The block encryption algorithm has high computational efficiency and does not need to record the encryption area coordinates and consider the selective encryption of complex encoding parameters like ROP encryption.

[0088] (4) The video is completely reversible. When necessary, the correct key can be used to decrypt the video to produce a video that is exactly the same as the original video, meeting the needs of authorized viewing or judicial digital forensics.

[0089] The video privacy protection method provided by this application is described below.

[0090] In some embodiments, the present application provides a video privacy protection method, and the following embodiments are described by taking the method applied to a video encryption device as an example. Figure 6 As shown, the video privacy protection method provided by this application includes the following steps:

[0091] S602: Obtain original encryption parameters and original video.

[0092] The original video may be a video that has not been processed for privacy protection, for example, an original surveillance video acquired by an acquisition device. The original video may include multiple original video frames, and the original video frame refers to a video frame that has not been processed for privacy protection. The original encryption parameter refers to information used to encrypt video encoding data. It can be understood that the method for obtaining the original video and the original encryption parameter can be determined according to actual conditions, and this document does not specifically limit this.

[0093] S604: for each original video frame, determine the privacy area of ​​the original video frame, and use a preset blur algorithm to perform image blurring processing on the privacy area of ​​the original video frame to obtain a blurred video frame.

[0094] The privacy area may be the image area corresponding to the privacy information in the original video frame. The preset blur algorithm refers to an image processing algorithm that can anonymize image data, which may be, but is not limited to, a Gaussian blur algorithm, a pixel blur algorithm (such as a mosaic algorithm), a ROP encryption algorithm, a generative adversarial network, and other algorithms.

[0095] For each frame of the original video, the video encryption device may first determine the target subject and target area in the original video frame that require privacy protection, and then determine the privacy area of ​​the original video frame.

[0096] In one example, the video encryption device can use an AI recognition algorithm to automatically identify the privacy area of ​​the original video frame. Furthermore, the AI ​​recognition algorithm can be implemented based on the YOLO model. The trained YOLO model can support the recognition of typical privacy targets including faces and license plates. The recognition results can include the target subject and the location coordinates of the privacy area of ​​each video frame, and the privacy area can be marked by a rectangular area.

[0097] In another example, the privacy area can be manually selected by the user. Furthermore, manually specifying the privacy area requires the support of a specific video viewing front end, and the user can mark the privacy area with a mouse or gesture. For example, when shooting with a fixed camera in the living room, the user can set the shooting area of ​​the bathroom and bedroom as a privacy area.

[0098] For each original video frame, after determining the privacy area of ​​the original video frame, the video encryption device can use a preset blur algorithm to process the image data corresponding to the privacy area, so that the processed blurred video frame satisfies visual anonymization and achieves privacy protection. In this application, by blurring and anonymizing the specified privacy area, it does not affect the video-based AI visual analysis and application capabilities (such as people / vehicle counting, human posture determination, etc.).

[0099] S606: Using the blurred video frame as input data of a base layer in a target encoder, using the original video frame as input data of an enhancement layer in a target encoder, performing video encoding using the target encoder, and obtaining first video encoding data.

[0100] Among them, the target encoder is an encoder that supports H.265 scalable encoding.

[0101] In this step, the video encryption device may use the blurred video frame as input data of the target encoder base layer BL, and the original clear video frame as input of the target encoder enhancement layer EL. In this way, the target encoder can process these two inputs in accordance with the H.265 scalable coding method and complete the encoding operation of the video image frame, thereby obtaining the first video encoding data.

[0102] It can be understood that the first video encoding data includes basic data and enhanced data. Basic data refers to the H.265 encoded data output by the base layer, which records the image frame data corresponding to the blurred video frame. Enhanced data refers to the H.265 encoded data output by the enhancement layer, which records the image frame data corresponding to the original video frame. Since scalable coding uses inter-layer predictive coding optimization technology, that is, the enhancement layer only additionally stores information that is different from the base layer, the first video encoding data only increases the data volume by about 10% to 15% compared to the encoded data obtained by the existing encoding method, and will not cause excessive additional burden on data storage.

[0103] S608: Encrypt the enhanced data in the first video encoding data according to the original encryption parameter to obtain second video encoding data.

[0104] The enhanced data is the data output by the enhancement layer.

[0105] Specifically, in the first video encoding data, the enhanced data is plain text data. If the video is played directly according to the first video encoding data, the encoder can parse and render the original video frame and present the effect of a clear version of the original video. It can be seen that the first video encoding data does not have a high privacy protection capability.

[0106] To achieve effective privacy protection, the video encryption device can encrypt the enhanced data in the first video encoding data and obtain the second video encoding data after encryption. It can be understood that compared with the first video encoding data, the basic data of the second video encoding data remains unchanged, and the enhanced data of the second video encoding data is the ciphertext data obtained by encrypting the enhanced data of the first video encoding data.

[0107] For example, if the first video encoding data includes multiple plaintext base data and multiple plaintext enhancement data, the video encryption device can perform encryption calculations on the multiple plaintext enhancement data respectively to obtain ciphertext enhancement data, and thereby obtain the second video encoding data. The second video encoding data may include multiple plaintext base data and multiple ciphertext enhancement data.

[0108] S610: Generate a privacy-preserving video based on the second video encoding data.

[0109] In this step, the video encryption device can form an entire privacy-protected scalable coded video based on the second video coding data, and obtain a privacy-protected video.

[0110] In this case, if a player is used to play the privacy-protected video, the player can only decode the base layer data and present a blurred playback visual effect in the privacy area, thus achieving the privacy protection of the video. Without knowing the key, the player cannot decrypt the enhanced layer data, and thus cannot restore the clear version of the original video image encoded in the enhanced layer.

[0111] In this application, the scalable capabilities of H.265 encoding technology can be used to achieve flexible and efficient video privacy protection, and the encryption and decryption reciprocity of cryptographic technology can be combined to achieve reversible restoration function, thereby taking into account both high efficiency and reversible restoration.

[0112] In some embodiments, encrypting the enhanced data in the first video encoding data according to the original encryption parameters includes:

[0113] Step A1: determining a unit identifier corresponding to target NAL unit data; wherein the target NAL unit data is any first NAL unit data included in the enhanced data, and the unit identifier is used to uniquely identify the first NAL unit data;

[0114] Step A2: Generate target encryption parameters according to the unit identifier and the original encryption parameters;

[0115] Step A3: Encrypt the payload data of the target NAL unit data according to the target encryption parameters.

[0116] In this embodiment, by introducing a unit identifier to perform data encryption, it can be ensured that each NAL unit data corresponding to the enhanced data is encrypted using a different encryption parameter, thereby further improving information security.

[0117] Specifically, the first encoded data includes a plurality of NAL unit data, and the plurality of NAL unit data includes NAL unit data corresponding to the basic data and NAL unit data corresponding to the enhanced data. For each NAL unit data corresponding to the enhanced data, the video encryption device determines a unit identifier of the NAL unit data, and encrypts the payload data of the NAL unit data according to the unit representation and the original encryption parameter.

[0118] In some examples, the unit identifier may be the arrangement sequence number of the NAL unit data in the first video encoding data. The video encryption device may read each NAL unit data of the enhancement layer, and set the number of the current NAL unit data as NAL_id (id starts counting from 1). The video encryption device may determine the target encryption parameter for encrypting the current NAL unit data according to the number of the current NAL unit data and the original encryption parameter, and encrypt accordingly.

[0119] In some embodiments, the original encryption parameters include an original initialization vector and an original encryption key, and the target encryption parameters include a target initialization vector and a target encryption key. The initialization vector refers to an initialization vector in a block cipher, which is used for video encryption. The encryption key refers to key information used for video encryption.

[0120] In one example, to improve data security and privacy protection, the original initialization vector and the original encryption key can be randomly generated using a random algorithm. Furthermore, the data length of the original initialization vector and the original encryption key are both greater than or equal to 128 bits to meet security strength requirements and further improve security.

[0121] Generate target encryption parameters based on the unit identifier and original encryption parameters, including:

[0122] Step A21: Using a preset hash algorithm, a hash calculation is performed on the unit identifier, the original initialization vector and the original encryption key to obtain a target hash value;

[0123] Step A22: Divide the target hash value into a target initialization vector and a target encryption key according to a preset division rule.

[0124] In this embodiment, in the process of generating the target encryption parameters corresponding to the target NAL data unit, the video encryption device may use a preset hash algorithm to perform a hash calculation on the initialization vector, the original encryption key, and the unit identifier corresponding to the target NAL data unit, and divide the target hash value obtained by the hash calculation according to a preset division rule to obtain a target initialization vector and a target encryption key. The video encryption device may use the target initialization vector and the target encryption key to perform an encryption calculation on the payload data of the target NAL unit data.

[0125] In one example, the video encryption device can use the commercial secret hash algorithm SM3, key (original encryption key), IV (original initialization vector) and the id value corresponding to the target NAL unit data to calculate the key stream SM3 (id, key, IV), id = 1, 2, 3 ... M, M is the total number of first NAL unit data. Then the first 128 bits of SM3 (id, key, IV) are used as the target encryption key key_id, and the last 128 bits of data are used as the target initialization vector IV_id.

[0126] In some embodiments, the payload data of the target NAL unit data is encrypted according to the target encryption parameter, including: according to the target encryption parameter, the payload data of the target NAL unit data is encrypted using the SM4-CTR encryption algorithm. Since CTR is a stream cipher mode, the length of the ciphertext and the plaintext can be guaranteed to be consistent, and the data length will not be increased after encryption, thereby reducing the data volume of the second video encoding data as much as possible.

[0127] In the above example, the video encryption device may encrypt the payload data payload of the target NAL unit data using the CTR encryption mode of the commercial encryption algorithm SM4 based on key_id and IV_id, specifically:

[0128] Cipher_payload=SM4_CTR_Encrypt(payload,key_id,IV_id)

[0129] Among them, Cipher_payload is the ciphertext data corresponding to payload.

[0130] In some embodiments, the enhancement data in the second video encoding data includes at least one SEI data and at least one second NAL unit data. The SEI data is used to record the SEI of the supplementary enhancement information. The second NAL unit data refers to the NAL unit data obtained by encrypting and calculating the payload data of the first NAL unit data. The second NAL unit data includes a type identification value, which is used to reflect the data type of the data recorded by the second NAL unit data.

[0131] Generate a privacy protection video based on the second video encoding data, including: for each second NAL unit data, write the type identification value of the second NAL unit data into the corresponding SEI data, and modify the type identification value of the second NAL unit data to an undefined identification value.

[0132] Specifically, the video encryption device may set the type of the NAL unit data corresponding to the enhancement layer in the second video encoding data to an undefined value specified in the encoding specification (for example, it may be set to 63), thereby telling the decoder to ignore this NAL unit data during decoding, thereby ensuring the correctness of the decoding. In addition, the video encryption device may retain the correct type identification value of the second NAL unit data in a custom field in the SEI preceding the NAL, so as to restore the correct NAL type when providing decryption.

[0133] In some embodiments, the original encryption parameters include an original initialization vector and an original encryption key. For relevant descriptions of the original initialization vector and the original encryption key, please refer to the above embodiments, which will not be repeated herein.

[0134] Generating a privacy-preserving video based on the second video encoding data also includes:

[0135] The original encryption key is encrypted using the preset password information to obtain a ciphertext key;

[0136] The ciphertext key and the original initialization vector are written into the first SEI data of the second video encoding data.

[0137] The preset password information may be preset and used to encrypt the frame encryption information and obtain encryption parameter data.

[0138] Considering that the original encryption key is difficult to remember, the original encryption key can be encrypted using a preset password. In this way, on the one hand, the original encryption key can be restored by the preset password during decryption, which is easy to remember, and on the other hand, security can be further improved to avoid the leakage of the original encryption key.

[0139] In this embodiment, the video encryption device can use preset password information to encrypt the original encryption key to obtain a ciphertext key, and write the ciphertext key and the plaintext data of the original initialization vector into the first SEI data of the second video encoded data, so that the second video encoded data carries frame encryption information for decryption.

[0140] The video playback method provided by this application is described below.

[0141] In some embodiments, the present application provides a video playback method, and the following embodiments are described by taking the method applied to a video playback device as an example. Figure 7 As shown, the video playback method provided by this application includes the following steps:

[0142] S702: Obtain a privacy-preserving video; wherein the privacy-preserving video is generated based on the video privacy protection method of any of the above embodiments;

[0143] S704: Obtaining original encryption parameters corresponding to the privacy-preserving video;

[0144] S706: Decrypt the enhanced data in the privacy-preserving video according to the original encryption parameters, and obtain the original video based on the decryption result.

[0145] In this embodiment, the video playback device can use the original encryption parameters to decrypt and restore the enhanced data in the privacy-protected video. Since the enhanced data in the privacy-protected video is generated based on the encryption algorithm and the coded data corresponding to the original video frame, after decryption, the video playback device can obtain the plaintext coded data corresponding to the original video frame, and then obtain a clear original video. In this way, authorized viewing and meeting the relevant requirements of legal evidence collection can be achieved.

[0146] In some examples, when the video playback device obtains the preset password information, it can perform decryption and restoration according to the following steps:

[0147] Step B1: Read the first SEI data from the video file of the privacy-preserving video, and read the original initialization vector and ciphertext key from the first SEI data.

[0148] Step B2: Decrypt the ciphertext key using the preset password information and obtain the original encryption key.

[0149] Step B3: Use the original encryption key and the original initialization vector to calculate the target key and target initialization vector corresponding to each second NAL unit data. For example, the video playback device can use the commercial secret hash algorithm SM3, key (original encryption key), IV (original initialization vector) and the id value corresponding to the second NAL unit data to calculate the key stream SM3 (id, key, IV), id = 1, 2, 3 ... M, M is the total number of second NAL unit data. Then use the first 128 bits of SM3 (id, key, IV) as the target encryption key key_id, and the last 128 bits of SM3 (id, key, IV) as the target initialization vector IV_id.

[0150] Step B4: Decrypt the payload data of each second NAL unit data using the target key and target initialization vector corresponding to each second NAL unit data, and obtain the plaintext payload. In one example, the decryption method can be performed according to the following expression:

[0151] payload=SM4_CTR_Decrypt(Cipher_payload,key_id,IV_id)

[0152] Step B5: For each second NAL unit data, read the correct type value from the SEI data preceding the second NAL unit data, and correct the type identification value of the second NAL unit data from 63 (ie, an undefined value) to a correct type value.

[0153] In this way, the entire video file can be restored to a plaintext video after scalable encoding. At this time, the playback can present the original clear version of the visual effect, removing the privacy protection. Due to the complete reversibility of encryption and decryption, the plaintext video originally encoded and the video obtained after decryption are completely consistent in data, which can meet the needs of video viewing and judicial evidence collection under key authorization.

[0154] The video privacy protection device provided in an embodiment of the present application is described below. The video privacy protection device described below and the video privacy protection method described above can be referenced to each other.

[0155] In some embodiments, Figure 8 As shown, the present application provides a video privacy protection device 800, which is applied to a video encryption device, including:

[0156] The original data acquisition module 802 is used to acquire original encryption parameters and original video; wherein the original video includes multiple original video frames;

[0157] A blur processing module 804 is used to determine the privacy area of ​​each original video frame, and perform image blur processing on the privacy area of ​​the original video frame using a preset blur algorithm to obtain a blurred video frame;

[0158] The video encoding module 806 is configured to use the blurred video frame as input data of a base layer in a target encoder, use the original video frame as input data of an enhancement layer in the target encoder, use the target encoder to perform video encoding, and obtain first video encoding data; wherein the target encoder is an encoder supporting H.265 scalable encoding;

[0159] A video encryption module 808, configured to encrypt the enhanced data in the first video encoding data according to the original encryption parameter to obtain second video encoding data; wherein the enhanced data is data output by the enhancement layer;

[0160] The privacy protection module 810 is used to generate a privacy protection video based on the second video encoding data.

[0161] In some embodiments, the video encryption module 808 of the present application includes:

[0162] An identification determination unit, used to determine a unit identification corresponding to the target NAL unit data; wherein the target NAL unit data is any first NAL unit data included in the enhanced data, and the unit identification is used to uniquely identify the first NAL unit data;

[0163] A target encryption parameter generating unit, used for generating a target encryption parameter according to the unit identifier and the original encryption parameter;

[0164] A payload encryption unit is used to encrypt the effective payload data of the target NAL unit data according to the target encryption parameter.

[0165] In some embodiments, the original encryption parameters include an original initialization vector and an original encryption key, and the target encryption parameters include a target initialization vector and a target encryption key. The target encryption parameter generation unit of the present application includes:

[0166] A hash calculation unit, configured to use a preset hash algorithm to perform a hash calculation on the unit identifier, the original initialization vector, and the original encryption key to obtain a target hash value;

[0167] The division unit is used to divide the target Hash value into the target initialization vector and the target encryption key according to a preset division rule.

[0168] In some embodiments, the load encryption unit of the present application includes:

[0169] The CTR encryption unit is used to encrypt the payload data of the target NAL unit data using the SM4-CTR encryption algorithm according to the target encryption parameters.

[0170] In some embodiments, the enhanced data in the second video encoding data includes at least one SEI data and at least one second NAL unit data, and the second NAL unit data includes a type identification value. The privacy protection module 810 of the present application includes:

[0171] The type identification value modification unit is used to write the type identification value of each second NAL unit data into the corresponding SEI data, and modify the type identification value of the second NAL unit data to an undefined identification value.

[0172] In some embodiments, the original encryption parameters include an original initialization vector and an original encryption key. The privacy protection module 810 of the present application also includes:

[0173] A key encryption unit, used to encrypt the original encryption key using a preset password information to obtain a ciphertext key;

[0174] A data writing unit is used to write the ciphertext key and the original initialization vector into the first SEI data of the second video encoding data.

[0175] The video playback device provided in an embodiment of the present application is described below. The video playback device described below and the video playback method described above can refer to each other.

[0176] In some embodiments, Fig. 9 As shown, the present application provides a video playback device 820, which is applied to a video playback device, including:

[0177] A video acquisition module 822 is used to acquire a privacy-preserving video; wherein the privacy-preserving video is generated based on the video privacy protection method described in any of the above embodiments;

[0178] An encryption parameter acquisition module 824 is used to obtain the original encryption parameters corresponding to the privacy protection video;

[0179] The decryption module 826 is used to decrypt the enhanced data in the privacy protection video according to the original encryption parameters, and obtain the original video based on the decryption result.

[0180] In one embodiment, the present application also provides a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the video privacy protection method in any embodiment, and / or execute the steps of the video playback method in any embodiment.

[0181] In one embodiment, the present application also provides a video encryption device, in which computer-readable instructions are stored. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the video privacy protection method in any embodiment.

[0182] In one embodiment, the present application further provides a video playback device, in which computer-readable instructions are stored. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the video playback method in any embodiment.

[0183] In some embodiments, the video encryption device and the video playback device of the present application can both be computer devices. Schematically, Fig.10 A schematic diagram of the internal structure of a computer device provided in an embodiment of the present application. Fig.10 , the computer device 900 includes a processing component 902, which further includes one or more processors, and a memory resource represented by a memory 901, for storing instructions that can be executed by the processing component 902, such as an application. The application stored in the memory 901 may include one or more modules, each corresponding to a set of instructions. In addition, the processing component 902 is configured to execute instructions to perform the steps of the method described in any of the above embodiments.

[0184] The computer device 900 may further include a power supply component 903 configured to perform power management of the computer device 900, a wired or wireless network interface 904 configured to connect the computer device 900 to a network, and an input / output (I / O) interface 905. The computer device 900 may operate based on an operating system stored in the memory 901, such as Windows Server TM, Mac OS X TM, Unix TM, Linux TM, Free BSD TM, or the like.

[0185] Those skilled in the art will understand that the internal structure of the computer device shown in the present application is merely a block diagram of a partial structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0186] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not clearly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the sentence "include one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. Herein, "one", "one", "said", "the" and "it" may also include plural forms, unless the context clearly indicates another way. A plurality refers to at least two cases, such as 2, 3, 5 or 8, etc. "And / or" includes any and all combinations of the relevant listed items.

[0187] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can refer to each other.

[0188] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A video privacy protection method, characterized in that: Applicable to video encryption equipment, including: Obtaining original encryption parameters and original video; wherein the original video includes multiple original video frames; For each of the original video frames, determine the privacy area of ​​the original video frame, and use a preset blur algorithm to perform image blurring processing on the privacy area of ​​the original video frame to obtain a blurred video frame; Using the blurred video frame as input data of a base layer in a target encoder, using the original video frame as input data of an enhancement layer in the target encoder, using the target encoder to perform video encoding, and obtaining first video encoding data; wherein the target encoder is an encoder supporting H.265 scalable encoding; Encrypting the enhanced data in the first video encoding data according to the original encryption parameter to obtain second video encoding data; wherein the enhanced data is data output by the enhancement layer; Generate a privacy-preserving video based on the second video encoding data.

2. The method according to claim 1, characterized in that The encrypting the enhanced data in the first video encoding data according to the original encryption parameter comprises: Determine a unit identifier corresponding to the target NAL unit data; wherein the target NAL unit data is any first NAL unit data included in the enhanced data, and the unit identifier is used to uniquely identify the first NAL unit data; Generate target encryption parameters according to the unit identifier and the original encryption parameters; The payload data of the target NAL unit data is encrypted according to the target encryption parameters.

3. The method according to claim 2, characterized in that The original encryption parameters include an original initialization vector and an original encryption key, and the target encryption parameters include a target initialization vector and a target encryption key; The step of generating a target encryption parameter according to the unit identifier and the original encryption parameter comprises: Using a preset hash algorithm, performing a hash calculation on the unit identifier, the original initialization vector, and the original encryption key to obtain a target hash value; According to a preset division rule, the target Hash value is divided into the target initialization vector and the target encryption key.

4. The method according to claim 2, characterized in that: The encrypting the payload data of the target NAL unit data according to the target encryption parameter comprises: According to the target encryption parameters, the SM4-CTR mode encryption algorithm is used to encrypt the payload data of the target NAL unit data.

5. The method according to any one of claims 1 to 4, characterized in that: The enhancement data in the second video encoding data includes at least one SEI data and at least one second NAL unit data, and the second NAL unit data includes a type identification value; The step of generating a privacy-preserving video based on the second video encoding data includes: For each of the second NAL unit data, the type identification value of the second NAL unit data is written into the corresponding SEI data, and the type identification value of the second NAL unit data is modified to an undefined identification value.

6. The method according to claim 5, characterized in that The original encryption parameters include an original initialization vector and an original encryption key; The step of generating a privacy-preserving video based on the second video encoding data further includes: Encrypting the original encryption key using a preset password information to obtain a ciphertext key; The ciphertext key and the original initialization vector are written into the first SEI data of the second video encoding data.

7. A video playback method, characterized in that: Applicable to video playback devices, including: Obtain a privacy-preserving video; wherein the privacy-preserving video is generated based on the video privacy protection method according to any one of claims 1 to 6; Obtaining original encryption parameters corresponding to the privacy-preserving video; The enhanced data in the privacy-preserving video is decrypted according to the original encryption parameters, and the original video is obtained based on the decryption result.

8. A video privacy protection device, characterized in that: Applicable to video encryption equipment, including: An original data acquisition module, used to acquire original encryption parameters and original video; wherein the original video includes a plurality of original video frames; A blur processing module, for determining the privacy area of ​​each original video frame, and performing image blur processing on the privacy area of ​​the original video frame using a preset blur algorithm to obtain a blurred video frame; A video encoding module, configured to use the blurred video frame as input data of a base layer in a target encoder, use the original video frame as input data of an enhancement layer in the target encoder, use the target encoder to perform video encoding, and obtain first video encoding data; wherein the target encoder is an encoder supporting H.265 scalable encoding; A video encryption module, used for encrypting the enhanced data in the first video encoding data according to the original encryption parameter to obtain second video encoding data; wherein the enhanced data is data output by the enhancement layer; A privacy protection module is used to generate a privacy protection video based on the second video encoding data.

9. A video playback device, characterized in that: Applicable to video playback devices, including: A video acquisition module, used to acquire a privacy-preserving video; wherein the privacy-preserving video is generated based on the video privacy protection method according to any one of claims 1 to 6; An encryption parameter acquisition module, used to obtain the original encryption parameters corresponding to the privacy protection video; A decryption module is used to decrypt the enhanced data in the privacy protection video according to the original encryption parameters, and obtain the original video based on the decryption result.

10. A storage medium, characterized in that: The storage medium stores computer-readable instructions, and when the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the video privacy protection method as described in any one of claims 1 to 6, and / or execute the steps of the video playback method as described in claim 7.

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