Image generation method and device, equipment and storage medium

Abstract

The invention provides an image generation method and device, equipment and a storage medium, and the method comprises the steps: responding to an image generation request for video stream data, and generating a target video frame of the video stream data based on the image positioning time corresponding to the image generation request; performing image display detection according to the target pixel data of the target video frame and image detection parameters to obtain an image detection result; and generating a target display image of the video stream data based on the image detection result of the target video frame and the target video frame. According to the technical scheme, the positioning accuracy and the image display effect of the cover thumbnail of the video stream data can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computer, in particular to an image generation method, device and equipment and storage medium. BACKGROUND

[0002] At present, with the rapid development of Internet technology and streaming media playing technology, more and more users play and watch multimedia videos through streaming media and other video applications. In the video application, the video content information can be obtained before playing the video by displaying the video cover image corresponding to each video data in the application, thereby improving the viewing experience. However, the existing video thumbnail image as the video cover image has image display abnormalities such as screen flashing, color deviation and black screen when displayed, resulting in poor display effect of the video thumbnail image and affecting the user viewing experience. SUMMARY

[0003] The embodiments of the present application provide an image generation method, device, equipment and storage medium, aiming at solving the technical problem of poor display effect of the video thumbnail image in the prior art.

[0004] In one aspect, the embodiments of the present application provide an image generation method, which comprises the following steps: In response to an image generation request for video stream data, a target video frame of the video stream data is generated based on an image positioning time corresponding to the image generation request; Image display detection is performed according to target pixel data of the target video frame and image detection parameters, and an image detection result is obtained; A target display image of the video stream data is generated based on the image detection result of the target video frame and the target video frame.

[0005] In one possible implementation of the present application, the image display detection is performed according to the target pixel data of the target video frame and the image detection parameters, and the image detection result is obtained, which comprises: A target pixel point in the target video frame is collected according to a preset detection mode, and target pixel data of the target pixel point is determined; A first image display detection is performed on the target video frame according to a pixel color component and a pixel component difference value of the target pixel data, and a first image detection result is obtained; A second image display detection is performed on the target video frame according to an image detection parameter and a target verification parameter corresponding to the target video frame, and a second image detection result is obtained; The image detection result of the target video frame is determined according to the first image detection result and the second image detection result.

[0006] In a possible implementation manner of the present application, the first image display detection of the target video frame according to the pixel color component of the target pixel data and the pixel component difference value comprises: The pixel color component of the target pixel data is obtained, and the pixel value color component difference between each target pixel data is calculated to obtain the pixel component difference value; If the pixel color component of each target pixel data is less than the pixel component threshold value, the first image detection result is determined as the first abnormal detection result; And / or, if each pixel component difference value is less than the component difference threshold value, the first image detection result is determined as the first abnormal detection result.

[0007] In a possible implementation manner of the present application, the second image display detection of the target video frame according to the image detection parameter corresponding to the target video frame and the target verification parameter comprises: The video frame image of the target video frame is collected by using a preset detection collection module, and the image detection parameter of the video frame image is calculated; If the image detection parameter and the target detection parameter are the same, the second image detection result is determined as the second normal display result; If the image detection parameter and the target detection parameter are different, the second image detection result is determined as the second abnormal detection result.

[0008] In a possible implementation manner of the present application, the target display image of the video stream data is generated based on the image detection result of the target video frame and the target video frame, comprising: If the image detection result is a normal detection result, the target video frame is format-converted to obtain the target display image corresponding to the video stream data; If the image detection result is an abnormal detection result, a preset thumbnail image or an update positioning time corresponding to an update video frame is determined as the target display image corresponding to the video stream data.

[0009] In a possible implementation manner of the present application, the target video frame of the video stream data is generated based on the image positioning time corresponding to the image generation request, comprising: The target key frame in the video stream data is obtained by using the image positioning time of the image generation request; The target key frame is decoded according to the display state data of the target key frame and a target decoder to obtain a decoded video frame, and the decoded video frame contains a frame display time; The decoded video frame with the same frame display time and the image positioning time as the target key frame is determined as a target video frame of the video stream data.

[0010] In a possible implementation of the present application, the decoding of the target key frame according to the display state data of the target key frame and the target decoder to obtain a decoded video frame comprises: obtaining display state data corresponding to the target key frame and a video encoding format of the target key frame; generating a target decoder corresponding to the target key frame based on the video encoding format and terminal decoding parameters; decoding the target key frame according to the display state data and the target decoder to obtain a decoded video frame.

[0011] In another aspect, the present application provides an image generation device, which comprises: a video positioning module configured to generate a target video frame of video stream data based on an image positioning time corresponding to an image generation request of the video stream data in response to the image generation request; a display detection module configured to perform image display detection according to target pixel data of the target video frame and image detection parameters to obtain an image detection result; an image generation module configured to generate a target display image of the video stream data based on the image detection result of the target video frame and the target video frame.

[0012] In another aspect, the present application further provides an image generation device, which comprises: one or more processors; a memory; and one or more application programs, wherein the one or more application programs are stored in the memory and configured to be executed by the processor to implement the steps of the image generation method.

[0013] In another aspect, the present application further provides a computer readable storage medium having a computer program stored thereon, wherein the computer program is loaded by a processor to execute the steps of the image generation method.

[0014] This application, in response to an image generation request for video stream data, generates a target video frame of the video stream data based on the image positioning time corresponding to the image generation request; performs image display detection based on the target pixel data and image detection parameters of the target video frame to obtain an image detection result; and generates a target display image of the video stream data based on the image detection result and the target video frame. This achieves the goal of generating a target video frame for a video thumbnail from video stream data using image positioning time, performing image display detection on the target video frame using the target pixel data and image detection parameters to determine if the target video frame has display anomalies such as black screen, color cast, or screen tearing, obtaining an image detection result, and generating a target display image of the video thumbnail of the video stream data based on the image detection result and the target video frame, thereby improving the positioning accuracy and image display effect of the cover thumbnail of the video stream data. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of a scene illustrating the image generation method according to an embodiment of this application; Figure 2 This is a flowchart illustrating one embodiment of the image generation method in this application. Figure 3 A schematic diagram of a scenario of an embodiment of a preset detection mode in the image generation method provided in this application; Figure 4 A flowchart illustrating an embodiment of the image generation method for precisely locating video frames provided in this application; Figure 5 This is a flowchart illustrating an embodiment of the image generation method provided in this application for decoding target keyframes. Figure 6 A schematic diagram of the structure of one embodiment of the image generation apparatus provided in this application; Figure 7 This is a schematic diagram of an embodiment of the image generation device provided in this application. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0019] In this application, the term "exemplary" is used to mean "serving as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0020] Currently, with the rapid development of internet technology and streaming media playback technology, more and more users are playing and watching multimedia videos through streaming media and other video applications. These applications can display video thumbnails corresponding to various video data, allowing users to obtain video content information before playback, thus enhancing the viewing experience. However, existing video thumbnails used as video thumbnails suffer from display anomalies such as screen tearing, color distortion, and black screens, resulting in poor display quality and negatively impacting the user's viewing experience.

[0021] Based on this, this application proposes an image generation method, apparatus, device, and computer-readable storage medium to solve the technical problem of poor display effect of video thumbnail images in the prior art.

[0022] The image generation method in this embodiment of the invention is applied to an image generation device, which is provided in an image generation equipment. The image generation equipment includes one or more processors, a memory, and one or more application programs. The one or more application programs are stored in the memory and configured to be executed by the processor to implement the image generation method. The image generation equipment can be a smart terminal, such as a mobile phone, tablet computer, network device, and smart computer. Optionally, the image generation equipment can also be a server or a service cluster composed of multiple servers.

[0023] like Figure 1 As shown, Figure 1 This is a schematic diagram of a scenario for an image generation method according to an embodiment of this application. In this embodiment of the invention, the image generation scenario includes an image generation device 100 (the image generation device 100 integrates an image generation apparatus), and the image generation device 100 is equipped with a computer-readable storage medium corresponding to the image generation method to execute the steps of the image generation method.

[0024] Understandable, Figure 1 The image generation device in the scenario of the image generation method shown, or the device included in the image generation device, does not constitute a limitation on the embodiments of the present invention. That is, the number or type of the image generation device in the scenario of the image generation method, or the number or type of the device included in each device, does not affect the overall implementation of the technical solution in the embodiments of the present invention, and can all be considered as equivalent substitutions or derivatives of the technical solutions claimed in the embodiments of the present invention.

[0025] In this embodiment of the invention, the image generation device 100 is mainly used for: responding to an image generation request for video stream data, generating a target video frame of the video stream data based on the image positioning time corresponding to the image generation request; performing image display detection based on the target pixel data and image detection parameters of the target video frame to obtain an image detection result; and generating a target display image of the video stream data based on the image detection result and the target video frame.

[0026] The image generation device 100 in this embodiment of the invention can be an independent image generation device, such as a mobile phone, tablet computer, smart TV, smart wearable device, virtual reality device, mixed reality device, augmented reality device and smart computer, or a corresponding server, or it can be an image generation network or image generation cluster composed of multiple image generation devices.

[0027] This application provides an image generation method, apparatus, device, and computer-readable storage medium, which will be described in detail below.

[0028] It will be understood by those skilled in the art that Figure 1 The application environment shown is only one application scenario related to the solution of this application and does not constitute a limitation on the application scenario of this application. Other application environments may include more than one application scenario. Figure 1 The number of more or fewer image generating devices shown, or the image generating network connectivity relationships, for example Figure 1 Only one image generation device is shown in the image. It is understood that the scenario of this image generation method may also include one or more image generation devices, which are not specifically limited here. The image generation device 100 may also include a memory for storing target video frames, image detection results, target display images and other data.

[0029] It should be noted that, Figure 1 The schematic diagram of the image generation method shown is merely an example. The scenarios of the image generation method described in the embodiments of the present invention are intended to more clearly illustrate the technical solutions of the embodiments of the present invention and do not constitute a limitation on the technical solutions provided in the embodiments of the present invention.

[0030] Based on the scenarios described above for image generation methods, various embodiments of the image generation method disclosed in this invention are proposed.

[0031] like Figure 2 As shown, Figure 2 This is a flowchart illustrating one embodiment of the image generation method in this application. The image generation method includes the following steps 201 to 203: 201. In response to an image generation request for video stream data, generate a target video frame of the video stream data based on the image positioning time corresponding to the image generation request; The image generation method in this embodiment is applied to an image generation device. The type and number of image generation devices are not specifically limited; that is, the image generation device can be one or more smart display terminals or other associated smart devices. In one specific embodiment, the image generation device is a smart TV. In another specific embodiment, the video playback device can be a smart computer, smartphone, tablet computer, or smart TV capable of watching streaming media and other video stream data.

[0032] Optionally, the image generation device includes a streaming media application such as a video playback application, which can respond to the target interactive object's selection to play specified video stream data. When the target interactive object browses the video stream data to be played through the video playback application or other applications (such as social media applications capable of video playback), the application can display video thumbnails corresponding to each video stream data to recommend videos to the target interactive object. The video thumbnail is a thumbnail image used to display the video content of the corresponding video stream data information to the user, allowing the target interactive object to view the video content without playing the video stream data, thereby enabling the target interactive object to select video stream data of interest for viewing. However, the video thumbnails generated in the prior art may have positioning errors, resulting in the generated thumbnails failing to effectively reflect the video content of the video stream data, and the generated video thumbnails may have image anomalies, resulting in poor display effects and affecting the user's viewing experience.

[0033] Optionally, the target interaction object can be a user or other application that interacts with a video playback application in the image generating device.

[0034] Optionally, video stream data refers to video data or corresponding video encoding data displayed in video playback applications or other applications. The target interactive object can perform interactive operations such as video playback, video navigation, video caching, and video sharing by clicking the video interactive controls corresponding to the video stream data. This video stream data can be online streaming video data or local video data stored in a local storage module.

[0035] Optionally, the image generation request is a request event that drives an image generation device or other third-party device to generate a video thumbnail image corresponding to the video stream data. Optionally, the triggering method of this image generation request is not specifically limited here; that is, the image generation request can be actively triggered by the user. For example, the user can actively trigger the image generation request by selecting the image generation button corresponding to the video stream data in a video playback application or other application to generate a thumbnail image corresponding to the video stream data for display as a video cover image. Furthermore, the image generation request can also be actively triggered by the image generation device. For example, after acquiring the video stream data, the image generation device automatically triggers an image generation request for that video stream data.

[0036] Optionally, after obtaining an image generation request for generating a cover thumbnail image corresponding to the video stream data, the image generation device parses the image generation request, obtains the image positioning time carried in the image generation request, uses the image positioning time to obtain the target key frame in the video stream data, and decodes and generates the target video frame pointed to by the image positioning time based on the target key frame.

[0037] Image localization time refers to the time parameter used to locate the video frame corresponding to the thumbnail image to be generated. This image localization time can be the video localization time passed to the image generation application in the image generation device by the video creator or other interactive object, enabling the image generation device to accurately locate the target video frame for the thumbnail image. In other words, when the user object of the video stream data to be generated can pass the time information of the video thumbnail to be acquired as the image localization time to the image generation device, it drives the image generation device to accurately acquire the video frame corresponding to the image localization time, thereby improving the accuracy of subsequent image generation.

[0038] Optionally, the target keyframe is video-encoded frame data in the video stream data that is associated with the image positioning time and contains complete image and pixel data. Optionally, in a specific embodiment, the target keyframe can be the nearest video keyframe before the image positioning time and subsequent video keyframes in the video stream data.

[0039] Optionally, after receiving an image generation request and determining the image positioning time corresponding to the request, the image generation device jumps the video stream data to the nearest keyframe before the specified time point, and determines the nearest video keyframe and subsequent video keyframes before the specified time point as target keyframes. Optionally, in one specific embodiment, the image generation device can configure a video jump (SeekMode) parameter using the image positioning time to generate a video positioning instruction corresponding to the video stream data based on the image positioning time and the video jump parameter, and use the video positioning instruction to jump to the nearest keyframe before the image positioning time position, thus determining the nearest keyframe and subsequent video keyframes as target keyframes corresponding to the video stream data, thereby improving subsequent decoding efficiency. Optionally, in one specific embodiment, the video positioning instruction is configured as SEEK_PREIVOUS_SYNC.

[0040] Optionally, after acquiring the target keyframe, the image generation device further creates a corresponding target decoder using the video encoding format of the target keyframe, and inputs the target keyframe and display status data into the target decoder for decoding to obtain a decoded video frame. It then acquires the target video frame pointed to by the image positioning time within the decoded video frame. The target video frame is the video frame in the video stream data that corresponds to the video thumbnail image in the video stream data to be generated at the image positioning time.

[0041] 202. Perform image display detection based on the target pixel data and image detection parameters of the target video frame to obtain the image detection result; Optionally, in order to improve the display effect of the target display image generated from the target video frame and thus avoid display abnormalities in the target display image, the image generation device performs image display detection on the target video frame after acquiring it to determine whether there are display abnormalities such as black screen or color cast in the target video frame, and then generates the corresponding target display image based on the display detection results.

[0042] Optionally, after acquiring the target video frame, the image generation device further acquires the target pixel data and image detection parameters of the target video frame, and performs image display detection based on the target pixel data and image detection parameters to determine whether the target video frame has any one or more display abnormalities such as color cast, black screen, and screen distortion, and then outputs the display detection result corresponding to the target video frame.

[0043] The display detection result refers to the image display detection result that characterizes whether the target video frame has display anomalies. Optionally, in a specific embodiment, the display detection result includes a first image detection result and a second image detection result. The first image detection result characterizes whether the target video frame has pixel color display anomalies. The second image detection result characterizes whether the target video frame has display errors due to data anomalies.

[0044] Optionally, the image generation device acquires target pixels in the target video frame according to a preset detection mode, and determines the target pixel data of the target pixels. Alternatively, as... Figure 4 As shown, Figure 4 These are schematic diagrams illustrating several embodiments of a preset detection mode for image display detection in the image generation method provided in this application. For example... Figure 4 As shown, to improve detection efficiency and reduce the computational burden of image display detection, the image generation device is pre-set with multiple preset detection modes for extracting pixels from target video frames as target pixels for image display detection. Optionally, such as... Figure 3 As shown, Figure 3 This is a schematic diagram of a scenario in an embodiment of a preset detection mode pre-set in the image generation method provided in this application. Figure 3 In the illustrated embodiment, the preset detection modes include at least one or more image detection modes such as intersecting mode, cross mode, "Z" pattern, "N" pattern, single square mode, double square mode, and double "Z" pattern. Optionally, in other embodiments, the image generation device can also utilize other detection modes to perform image display detection on the target video frame.

[0045] Optionally, the image generation device acquires target pixels in the target video frame according to a preset detection mode, obtaining target pixel data for those target pixels. Here, the target pixel refers to the selected video frame pixel for image display detection within the target video frame. For example... Figure 3 As shown, different preset detection modes select different target pixels for image display detection. For example, the cross mode selects video frame pixels on the diagonal of the target video frame as target pixels. The cross mode selects video frame pixels on the horizontal line passing through the center point of the target video frame and the vertical line passing through the center point of the target video frame as target pixels, etc.

[0046] Optionally, after acquiring the target pixels in the target video frame, the image generating device also acquires the target pixel data. That is, the image generating device acquires the pixel color components of each target pixel, calculates the difference between pixel color components of the same color, obtains the pixel component difference value, and determines the pixel color component and the pixel component difference value as the target pixel data. Here, the pixel color component is the intensity parameter of each color channel in the target pixel. For example, in one specific embodiment, the pixel color component includes any one or more of the pixel red component, pixel green component, and pixel red component.

[0047] Optionally, after acquiring the target pixel data, the image generation device performs a first image display detection on the target video frame based on the pixel color components and pixel component differences of the target pixel data, and obtains a first image detection result. That is, the image generation device uses the pixel color components and pixel component differences of the target pixel data to perform a first image display detection on the target video frame, thereby determining whether the target video frame is a solid color video frame with no video content or a black screen video frame.

[0048] Optionally, the image generation device pre-sets a pixel component threshold for detecting whether the target video frame is a black screen video frame, and a component difference threshold for detecting whether the target video frame is a solid color video frame. The pixel component threshold and component difference threshold are used to determine whether the target video frame has a black screen or no video content, or whether the video frame is a solid color video frame, so as to output the first image detection result.

[0049] Optionally, if the image generation device determines that the pixel color components of each target pixel data in the target video frame are all less than the pixel component threshold, then the target video frame is determined to be a black screen video frame, and the first image detection result of the target video frame is determined to be the first anomaly detection result. The first anomaly detection result is a display detection result that characterizes the presence of color anomalies in the target video frame.

[0050] Optionally, in another specific embodiment, if the image generating device determines that the pixel component difference between each target pixel in the target video frame is less than the component difference threshold, then the target video frame is determined to be a solid color video frame with no video content and the video picture is a solid color picture, and the first image detection result of the target video frame is determined to be the first anomaly detection result.

[0051] Optionally, to avoid abnormal display problems such as screen tearing in the subsequently generated target display image due to data anomalies during the acquisition of the target video frame, the image generation device acquires the image detection parameters of the target video frame after acquiring it, and performs a second image display detection on the target video frame based on the image detection parameters and target verification parameters corresponding to the target video frame to obtain a second image detection result.

[0052] Optionally, the image detection parameter is a data detection parameter that characterizes the data information of the target video frame. Optionally, in one specific embodiment, the image detection parameter is the video frame hash value corresponding to the target video frame. For example, the image detection parameter can be the MD5 value of the target video frame.

[0053] Optionally, the target verification parameter is a data verification parameter corresponding to the normal display of the target video frame, used to determine whether data anomalies occur during the decoding and display process of the target video frame. Optionally, this target verification parameter can be the video hash value corresponding to the target video frame in its normal display state.

[0054] Optionally, after acquiring the target video frame, the image generation device uses a preset detection and acquisition module to acquire the video frame image corresponding to the target video frame, and calculates the image detection parameters of the video frame image. That is, the image generation device calculates the image hash value of the video frame image, determines the image hash value as the image detection parameter of the video frame image, and compares the image detection parameter with the image verification parameter to determine whether the target video frame has data anomalies during video processing, and obtains the corresponding second image detection result.

[0055] Optionally, if the image generation device determines that the image detection parameters and the target detection parameters are the same, then the image generation device determines that the target video frame did not have any data abnormalities during video processing, and determines that the second image detection result is the second normal detection result; Optionally, if the image generation device determines that the image detection parameters and the target detection parameters are different, the image generation device determines that the target video frame has data abnormality during video processing, and determines the second image detection result as the second abnormality detection result.

[0056] Optionally, after obtaining the first image detection result and the second image detection result, the image generation device further determines the image detection result of the target video frame based on the first image detection result and the second image detection result.

[0057] Optionally, if the first image detection result is a first normal display result and the second image detection result is a second normal display result, then the image generating device determines that the image detection result of the target video frame is a normal detection result.

[0058] Optionally, if the first image detection result is a first abnormal display result and / or the second image detection result is a second abnormal display result, the image generating device determines that the image detection result of the target video frame is an abnormal detection result.

[0059] 203. Generate the target display image of the video stream data based on the image detection results of the target video frame and the target video frame.

[0060] Optionally, after acquiring the image detection result of the target video frame, the image generation device also generates a target display image of the video stream data based on the image detection result and the target video frame.

[0061] The target display image is a thumbnail image of the video corresponding to the video content information of the video stream data. Optionally, in one specific embodiment, after generating the target display image, the image generating device displays the target display image as the video cover image corresponding to the video data, so that the target interactive object can perceive the video content of the video stream data through the target display image, making it convenient for the target interactive object to watch the video stream data of interest based on the target display image.

[0062] Optionally, after obtaining the image detection result of the target video frame, if the image generation device determines that the image detection result is a normal detection result, it uses the target video frame to generate the target display image of the video stream data. That is, the image generation device performs format conversion on the target video frame whose image detection result is a normal detection result to obtain the target display image corresponding to the video stream data.

[0063] Optionally, after acquiring a target video frame whose image detection result is normal, the image generation device uses an image conversion function to perform format conversion on the target video frame, converting it into converted image data in a first display format. The image conversion function is a conversion function used to perform image conversion on the target video frame. In one specific embodiment, the image conversion function is the `dataConvert` function. The first display format is the display format corresponding to the target video frame after format conversion. The converted image data is thumbnail image data obtained from the format conversion of the target video frame. In one specific embodiment, the first display format is a color model format used to describe the composition of pixels; for example, the first display format can be RGBA format or other display formats.

[0064] Optionally, after acquiring the converted image data, the image generation device further determines whether to compress the converted image data to reduce the storage and bandwidth usage of the video thumbnail. That is, the image generation device acquires the storage space corresponding to the converted image data, compares this storage space with a preset storage threshold, and determines whether to compress the converted image data based on the comparison result to obtain the target display image.

[0065] Optionally, if the image generation device determines that the storage space occupied by the converted image data is less than a preset storage threshold, the image generation device determines that the converted image data occupies a small amount of memory and there is no need to compress the converted image data, and determines the converted image data as the target display image corresponding to the video stream data.

[0066] Optionally, if the storage space occupied by the converted image data by the image generation device exceeds a preset storage threshold, the image generation device determines that the converted image data occupies a large amount of memory, compresses the converted image data, compresses it into compressed image data in a second display format, and determines the compressed image data as the target display image corresponding to the video stream data. Optionally, the second display format is the display format corresponding to the lossless compression of the converted video frames. In a specific embodiment, the second display format is a PNG file format.

[0067] Optionally, if the image generating device determines that the display detection result is an anomaly, it determines the preset thumbnail image or the updated video frame corresponding to the updated positioning time as the target display image corresponding to the video stream data. That is, after determining that the target video frame has a display anomaly, the image generating device determines the preset thumbnail image as the target display image corresponding to the video stream data; or, the image generating device receives the updated positioning time, obtains the updated video frame corresponding to the updated positioning time, performs format conversion on the updated video frame, and obtains the target display image corresponding to the video stream data. The preset thumbnail image is a pre-set default reminder image used to indicate that there is currently no valid video thumbnail image for the video stream data.

[0068] The update positioning time is the time parameter used to reposition the video frame image corresponding to the thumbnail image to be generated. The update video frame is the video frame image to be re-acquired and used to generate the corresponding thumbnail image.

[0069] In this embodiment, the image generation device responds to an image generation request for video stream data, generates a target video frame of the video stream data based on the image positioning time corresponding to the image generation request, performs image display detection based on the target pixel data and image detection parameters of the target video frame, and obtains an image detection result. Based on the image detection result and the target video frame, a target display image of the video stream data is generated. This achieves the goal of generating a target video frame for the video stream data to be used as a thumbnail based on the image positioning time, and performing image display detection on the target video frame using the target pixel data and image detection parameters to determine whether the target video frame has display anomalies such as black screen, color cast, or screen distortion, obtaining an image detection result, and generating a target display image of the video thumbnail of the video stream data based on the image detection result and the target video frame, thereby improving the positioning accuracy and image display effect of the cover thumbnail of the video stream data.

[0070] like Figure 4 As shown, Figure 4 This is a flowchart illustrating one embodiment of the image generation method for precisely locating video frames provided in this application. Figure 4 In the illustrated embodiment, the image generation method further includes steps 301 to 303: 301. Obtain the target keyframe in the video stream data using the image positioning time of the image generation request; 302. Decode the target keyframe according to the display status data of the target keyframe and the target decoder to obtain a decoded video frame, wherein the decoded video frame contains the frame display time; 303. Determine the decoded video frame whose frame display time is the same as the image positioning time as the target video frame of the video stream data.

[0071] Based on the above embodiments, in this embodiment, in order to improve the accuracy of the target display image in displaying the video content of the video stream data and to avoid image display abnormalities such as color cast in the target display image, the image generation device uses the image positioning time to locate the target video frame in the video stream data to be generated as the target display image.

[0072] Optionally, after receiving an image generation request and determining the image positioning time corresponding to the image generation request, the image generation device jumps the video stream data to the nearest keyframe before the specified time point, and determines the nearest video keyframe before the specified time point and subsequent video keyframes as target keyframes.

[0073] Optionally, after acquiring the target keyframe, the image generation device further creates a corresponding target decoder using the video encoding format of the target keyframe, and inputs the target keyframe and display status data into the target decoder for decoding to obtain a decoded video frame. It then acquires the target video frame pointed to by the image positioning time within the decoded video frame. The target video frame is the video frame in the video stream data that corresponds to the video thumbnail image in the video stream data to be generated at the image positioning time.

[0074] Optionally, after acquiring the target keyframe associated with the image generation request, the image generation device also decodes the target keyframe based on the display status data of the target keyframe and the target decoding data to obtain a decoded video frame carrying the frame display time, thereby improving the decoding effect and reducing the probability of display abnormalities such as color cast or black screen in the decoded video frame generated by decoding.

[0075] Optionally, after decoding the target keyframe to obtain each decoded video frame carrying a unique frame display time, the image generation device further determines the target video frame associated with the image positioning time based on the frame display time and the image positioning time. The target video frame is the video frame in the video stream data that is at the image positioning time and is to be used to generate the video thumbnail image.

[0076] Optionally, after acquiring the decoded video frame, the image generating device also parses the decoded video frame, obtains the frame display time corresponding to the decoded video frame, and compares the frame display time with the image positioning time to determine the target video frame corresponding to the image positioning time.

[0077] Optionally, if the image generating device determines that the frame display time is less than the image positioning time, the image generating device determines that the decoded video frame is not the target video frame corresponding to the specified playback position, and filters the decoded video frame corresponding to the frame display time.

[0078] Optionally, if the image generating device determines that the frame display time is equal to the image positioning time, then the decoded video frame corresponding to the frame display time is determined to be the decoded video frame of the video thumbnail image to be generated pointed to by the image positioning time, and the decoded video frame corresponding to the frame display time is determined as the target video frame, thereby achieving accurate positioning of the target video frame corresponding to the video thumbnail image to be generated.

[0079] In this embodiment, the image generation device obtains the target keyframe in the video stream data by utilizing the image positioning time of the image generation request; it decodes the target keyframe according to the display status data of the target keyframe and the target decoder to obtain a decoded video frame, which contains the frame display time; the decoded video frame with the same frame display time as the image positioning time is determined as the target video frame of the video stream data. This achieves accurate positioning of the video frame in the video stream data to be used to generate the cover thumbnail, ensuring that the generated target display image accurately reflects the content of the video stream data. It also optimizes the decoding process of video keyframes during thumbnail generation, avoiding image anomalies such as color cast in the generated cover thumbnail, thereby improving the positioning accuracy and image display effect of the cover thumbnail.

[0080] like Figure 5 As shown, Figure 5 This is a flowchart illustrating an embodiment of the image generation method provided in this application for decoding target keyframes, as shown below. Figure 5 In the illustrated embodiment, the image generation method further includes steps 401 to 403: 401. Obtain the display status data corresponding to the target keyframe and the video encoding format of the target keyframe; 402. Generate the target decoder corresponding to the target keyframe based on the video encoding format and terminal decoding parameters; 403. Decode the target keyframe according to the display status data and the target decoder to obtain a decoded video frame.

[0081] Based on the above embodiments, in this embodiment, after the image generating device obtains the target keyframe associated with the image generating request, it also decodes the target keyframe according to the display status data of the target keyframe and the target decoder to obtain a decoded video frame carrying the frame display time, thereby improving the decoding effect and reducing the probability of display abnormalities such as color cast or black screen in the decoded video frame generated by decoding.

[0082] Optionally, the display status data is a data parameter used to dynamically adjust the display status of the video frame corresponding to the target keyframe. Optionally, in a specific embodiment, the display status parameter can be dynamic metadata corresponding to the target keyframe. This display status parameter can adjust the display parameters such as brightness, contrast, hue, and saturation of the video frame corresponding to the target keyframe to improve the visual display effect of the decoded video frame.

[0083] Optionally, the target decoder is a video decoder used for video decoding of the target keyframe. Optionally, the target decoder can be either a target software decoder or a target hardware decoder. The target software decoder is a video software decoder used for software decoding of the target keyframe. The target hardware decoder is a video hardware decoder that utilizes target hardware to accelerate the decoding of the target keyframe.

[0084] Optionally, after acquiring the target keyframe corresponding to the image positioning time, the image generation device also acquires the display state data corresponding to the target keyframe and the video encoding format of the target keyframe. That is, after acquiring the target keyframe, the image generation device acquires the display state data corresponding to the target keyframe and determines the video encoding format corresponding to the target keyframe. Here, the video encoding format refers to the encoding format used for compressing and storing video stream data. Optionally, in a specific embodiment, the video encoding format corresponding to the video stream data can be an encoding format such as AVC or HEVC.

[0085] Optionally, after acquiring the video encoding format of the target keyframe, the image generation device generates a target decoder corresponding to the target keyframe based on the video encoding format and the terminal decoding parameters. The terminal decoding parameters refer to the parameter information of the encoding formats that the decoding chip of the image generation device can decode.

[0086] In other words, the image generation device matches the acquired video encoding format with the supported decoding formats in the terminal decoding parameters to determine whether the image generation device supports hardware decoding of the video encoding format, and then generates the corresponding target decoder. The supported decoding formats are decoding format information that characterizes the image generation device's ability to perform hardware decoding of video data in the corresponding video encoding format.

[0087] Optionally, if the terminal encoding parameters have a supported decoding format that is the same as the video encoding format, that is, if the image generation device supports video hardware decoding of the video data corresponding to the video encoding format, then the image generation device generates the hardware decoder corresponding to the supported decoding format as the target decoder for the target keyframe.

[0088] Optionally, if there is no supported decoding format in the video encoding parameters that is the same as the video encoding format, it is determined that the image generation device does not support video hardware decoding of the video data corresponding to the video encoding format, and the image generation device creates a software decoder as the target decoder for the target keyframe.

[0089] Optionally, after acquiring the target decoder corresponding to the target keyframe, the image generation device decodes the target keyframe based on the display status data and the target decoder to obtain a decoded video frame. That is, the image generation device combines the display status data and the target keyframe, and inputs the combined display status data and the target keyframe into the target decoder for decoding to generate a decoded video frame, thereby reducing the probability of display image abnormalities such as color cast in the decoded video frame.

[0090] Optionally, after decoding the target keyframe, the image generation device also obtains the decoder status of the target decoder. If the target decoder status indicates successful decoding, it obtains the decoded video frame corresponding to the target keyframe and the frame display time corresponding to the decoded video frame. The frame display time is parameter information used to mark the display time of the decoded video frame.

[0091] Optionally, in one specific embodiment, the encoding format corresponding to the target keyframe is Dolby Vision encoding format. The image generation device generates a target decoder corresponding to the target keyframe as a Dolby Vision hardware decoder, and combines the target keyframe and the corresponding display state data (RPU dynamic metadata) to obtain the decoder input data of the target decoder. The decoder input data is input to the target decoder for decoding to generate a decoded video frame that can present the Dolby HDR effect.

[0092] Optionally, in one specific embodiment, when decoding the target keyframe, the image generation device also obtains the keyframe type of the target keyframe, and decodes the target keyframe based on the keyframe type to obtain a decoded video frame.

[0093] Optionally, the image generation obtains the keyframe type of the target keyframe, which includes a first keyframe type and a second keyframe type. The keyframe type is the coded video frame type corresponding to the coded frame structure representing the target keyframe. The first keyframe type is the coded video frame type indicating that the target keyframe is independently coded and does not rely on other frames for decoding. The second keyframe type is the coded video frame type that relies on other coded video frames for decoding. Optionally, in a specific embodiment, the target keyframe corresponding to the first keyframe type is an I-frame. The target keyframes corresponding to the second keyframe type are P-frames and B-frames.

[0094] Optionally, if the image generation device determines that the keyframe type of the target keyframe is a first keyframe type, the image generation device decodes the target keyframe according to the display state data and the target decoder to obtain a first decoded video frame. The first decoded video frame is a decoded video frame generated by independently decoding the target keyframe of the first keyframe type.

[0095] Optionally, if the image generation device determines that the keyframe type of the target keyframe is a second keyframe type, the image generation device obtains the reference keyframe corresponding to the target keyframe, and decodes the target keyframe and the corresponding reference keyframe according to the display state data of the target keyframe and the target decoder to obtain a second decoded video frame. The second decoded video frame is a decoded video frame generated by jointly decoding the target keyframe of the second keyframe type.

[0096] In this embodiment, the image generation device acquires the display status data corresponding to the target keyframe and the video encoding format of the target keyframe; generates a target decoder corresponding to the target keyframe based on the video encoding format and terminal decoding parameters; and decodes the target keyframe according to the display status data and the target decoder to obtain a decoded video frame. This achieves decoding of the target keyframe based on its display status data and the target decoder to obtain a decoded video frame carrying the frame display time, thereby improving the decoding effect and reducing the probability of display anomalies such as color distortion or black screen in the generated decoded video frame.

[0097] To better implement the image generation method in the embodiments of this application, an image generation apparatus is also provided in the embodiments of this application, such as... Figure 6 As shown, Figure 6 This is a schematic diagram of one embodiment of the image generation apparatus provided in this application. Specifically, the image generation apparatus 500 includes: The video positioning module 501 is configured to respond to an image generation request for video stream data and generate a target video frame of the video stream data based on the image positioning time corresponding to the image generation request. The display detection module 502 is configured to perform image display detection based on the target pixel data and image detection parameters of the target video frame, and obtain the image detection result. The image generation module 503 is configured to generate a target display image of the video stream data based on the image detection result of the target video frame and the target video frame.

[0098] In one possible implementation of this embodiment, the image generation device performs image display detection based on the target pixel data of the target video frame and image detection parameters to obtain an image detection result, including: Collect target pixels in the target video frame according to a preset detection mode, and determine the target pixel data of the target pixels; Based on the pixel color components and pixel component differences of the target pixel data, a first image display detection is performed on the target video frame to obtain a first image detection result; The second image display detection is performed on the target video frame based on the image detection parameters and target verification parameters corresponding to the target video frame, and the second image detection result is obtained. The image detection result of the target video frame is determined based on the first image detection result and the second image detection result.

[0099] In one possible implementation of this embodiment, the image generation device performs a first image display detection on the target video frame based on the pixel color components and pixel component differences of the target pixel data to obtain a first image detection result, including: Obtain the pixel color components of the target pixel data, calculate the pixel value color component difference between each target pixel data, and obtain the pixel component difference; If the pixel color component of each of the target pixel data is less than the pixel component threshold, then the first image detection result is determined to be the first anomaly detection result. And / or, if the difference between each of the pixel components is less than the component difference threshold, then the first image detection result is determined to be the first anomaly detection result.

[0100] In one possible implementation of this embodiment, the image generation device performs a second image display detection on the target video frame based on the image detection parameters and target verification parameters corresponding to the target video frame, and obtains a second image detection result, including: The target video frame is acquired using a preset detection and acquisition module, and the image detection parameters of the video frame are calculated. If the image detection parameters and the target detection parameters are the same, then the second image detection result is determined to be the second normal display result; If the image detection parameters and the target detection parameters are different, then the second image detection result is determined to be the second anomaly detection result.

[0101] In one possible implementation of this embodiment, the image generation device generates a target display image of the video stream data based on the image detection result of the target video frame and the target video frame, including: If the image detection result is a normal detection result, then the target video frame is format converted to obtain the target display image corresponding to the video stream data; If the image detection result is an anomaly detection result, then the preset thumbnail image or the updated video frame corresponding to the update positioning time is determined as the target display image corresponding to the video stream data.

[0102] In one possible implementation of this embodiment, the image generation device generates a target video frame of the video stream data based on the image positioning time corresponding to the image generation request, including: The target keyframe in the video stream data is obtained using the image positioning time of the image generation request. The target keyframe is decoded based on the display status data of the target keyframe and the target decoder to obtain a decoded video frame, which contains the frame display time. Decoded video frames whose frame display time is the same as the image positioning time are identified as the target video frames of the video stream data.

[0103] In one possible implementation of this embodiment, the image generation device decodes the target keyframe based on the display state data of the target keyframe and the target decoder to obtain a decoded video frame, including: Obtain the display status data corresponding to the target keyframe and the video encoding format of the target keyframe; Generate the target decoder corresponding to the target keyframe based on the video encoding format and terminal decoding parameters; The target keyframe is decoded based on the display status data and the target decoder to obtain a decoded video frame.

[0104] In this embodiment, the image generation device responds to an image generation request for video stream data, generates a target video frame of the video stream data based on the image positioning time corresponding to the image generation request, performs image display detection based on the target pixel data and image detection parameters of the target video frame, and obtains an image detection result. Based on the image detection result and the target video frame, a target display image of the video stream data is generated. This achieves the goal of generating a target video frame of the video stream data to be used as a thumbnail through image positioning time, and performing image display detection on the target video frame using the target pixel data and image detection parameters to determine whether the target video frame has display anomalies such as black screen, color cast, and screen distortion, obtaining an image detection result, and generating a target display image of the video thumbnail of the video stream data based on the image detection result and the target video frame, thereby improving the positioning accuracy and image display effect of the cover thumbnail of the video stream data.

[0105] This invention also provides an image generation device, such as... Figure 7 As shown, Figure 7This is a schematic diagram of an embodiment of the image generation device provided in this application.

[0106] The image generation device integrates any one of the image generation apparatuses provided in the embodiments of the present invention, and the image generation device includes: One or more processors; Memory; and One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the processor in the steps of the image generation method described in any of the above-described embodiments of the image generation method.

[0107] Specifically, the image generation device may include components such as a processor 601 with one or more processing cores, a memory 602 with one or more computer-readable storage media, a power supply 603, and an input unit 604. Those skilled in the art will understand that... Figure 7 The image generation device structure shown does not constitute a limitation on the image generation device and may include more or fewer components than shown, or combine certain components, or have different component arrangements. Wherein: The processor 601 is the control center of the image generation device. It connects various parts of the image generation device via various interfaces and lines. By running or executing software programs and / or modules stored in the memory 602, and by calling data stored in the memory 602, it performs various functions and processes data of the image generation device, thereby providing overall monitoring of the image generation device. Optionally, the processor 601 may include one or more processing cores; preferably, the processor 601 may integrate an application processor and a modem processor, wherein the application processor mainly handles the operating system, user interface, and applications, and the modem processor mainly handles wireless communication. It is understood that the modem processor may not be integrated into the processor 601.

[0108] The memory 602 can be used to store software programs and modules. The processor 601 executes various functional applications and data processing by running the software programs and modules stored in the memory 602. The memory 602 may mainly include a program storage area and a data storage area. The program storage area may store the operating system, application programs required for at least one function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created based on the use of the image generation device, etc. In addition, the memory 602 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other volatile solid-state storage device. Accordingly, the memory 602 may also include a memory controller to provide the processor 601 with access to the memory 602.

[0109] The image generation device also includes a power supply 603 that supplies power to the various components. Preferably, the power supply 603 can be logically connected to the processor 601 through a power management system, thereby enabling functions such as charging, discharging, and power consumption management through the power management system. The power supply 603 may also include one or more DC or AC power supplies, a recharging system, a power fault detection circuit, a power converter or inverter, a power status indicator, or any other components.

[0110] The image generation device may also include an input unit 604, which can be used to receive input digital or character information and generate keyboard, mouse, joystick, optical or trackball signal inputs related to user settings and function control.

[0111] Although not shown, the image generating device may also include a display unit, etc., which will not be described in detail here. Specifically, in this embodiment, the processor 601 in the image generating device loads the executable files corresponding to the processes of one or more applications into the memory 602 according to the following instructions, and the processor 601 runs the applications stored in the memory 602 to realize various functions, as follows: In response to an image generation request for video stream data, a target video frame of the video stream data is generated based on the image positioning time corresponding to the image generation request. Image display detection is performed based on the target pixel data and image detection parameters of the target video frame to obtain the image detection result; The target display image of the video stream data is generated based on the image detection results of the target video frame and the target video frame.

[0112] Therefore, embodiments of the present invention provide a computer-readable storage medium, which may include: read-only memory (ROM), random access memory (RAM), a magnetic disk, or an optical disk, etc. A computer program is stored thereon, which is loaded by a processor to execute the steps in any of the image generation methods provided in the embodiments of the present invention. For example, the computer program loaded by the processor can execute the following steps: In response to an image generation request for video stream data, a target video frame of the video stream data is generated based on the image positioning time corresponding to the image generation request. Image display detection is performed based on the target pixel data and image detection parameters of the target video frame to obtain the image detection result; The target display image of the video stream data is generated based on the image detection results of the target video frame and the target video frame.

[0113] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the detailed descriptions of other embodiments above, which will not be repeated here.

[0114] In practice, each of the above units or structures can be implemented as an independent entity or can be arbitrarily combined to be implemented as the same or several entities. For the specific implementation of each of the above units or structures, please refer to the previous method embodiments, which will not be repeated here.

[0115] For details on the implementation of each of the above operations, please refer to the previous examples, which will not be repeated here.

[0116] The above provides a detailed description of an image generation method provided by the embodiments of this application. Specific embodiments have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An image generation method characterized by, The image generation method comprises: in response to an image generation request for video stream data, generating a target video frame of the video stream data based on an image positioning time corresponding to the image generation request; performing image display detection according to target pixel data of the target video frame and image detection parameters, to obtain an image detection result; generating a target display image of the video stream data based on the image detection result of the target video frame and the target video frame.

2. The image generation method according to claim 1, characterized by, The image display detection according to the target pixel data of the target video frame and the image detection parameters comprises: collecting target pixel points in the target video frame according to a preset detection mode, to determine target pixel data of the target pixel points; performing first image display detection on the target video frame according to pixel color components and pixel component difference values of the target pixel data, to obtain a first image detection result; performing second image display detection on the target video frame according to image detection parameters and target verification parameters corresponding to the target video frame, to obtain a second image detection result; determining the image detection result of the target video frame according to the first image detection result and the second image detection result.

3. The image generation method according to claim 2, characterized by, The first image display detection on the target video frame according to the pixel color components and the pixel component difference values of the target pixel data comprises: obtaining pixel color components of the target pixel data, and calculating pixel value color component difference values between the target pixel data, to obtain pixel component difference values; if the pixel color components of the target pixel data are all less than a pixel component threshold value, determining the first image detection result as a first abnormal detection result; and / or, if the pixel component difference values are all less than a component difference value threshold value, determining the first image detection result as a first abnormal detection result.

4. The image generation method of claim 2, wherein, The second image display detection on the target video frame according to the image detection parameters and the target verification parameters corresponding to the target video frame comprises: collecting a video frame image of the target video frame by using a preset detection collection module, and calculating image detection parameters of the video frame image; if the image detection parameters and the target detection parameters are the same, determining the second image detection result as a second normal display result; if the image detection parameters and the target detection parameters are different, determining the second image detection result as a second abnormal detection result.

5. The image generation method of claim 1, wherein, The generation of the target display image of the video stream data based on the image detection result of the target video frame and the target video frame comprises: if the image detection result is a normal detection result, performing format conversion on the target video frame, to obtain a target display image corresponding to the video stream data; if the image detection result is an abnormal detection result, determining a preset thumbnail image or an updated video frame corresponding to an updated positioning time as the target display image corresponding to the video stream data.

6. The image generation method according to claims 1-5, characterized in that, The generation of the target video frame of the video stream data based on the image positioning time corresponding to the image generation request comprises: The target key frame in the video stream data is obtained according to a display state data of the target key frame and a target decoder. The target key frame is decoded according to the display state data of the target key frame and the target decoder, to obtain a decoded video frame, wherein the decoded video frame comprises a frame display time. The decoded video frame with the same frame display time and image positioning time as the target key frame is determined as the target video frame of the video stream data.

7. The image generation method of claim 6, wherein, The decoding of the target key frame according to the display state data of the target key frame and the target decoder comprises: The display state data corresponding to the target key frame and the video encoding format of the target key frame are obtained. The target decoder corresponding to the target key frame is generated based on the video encoding format and terminal decoding parameters. The target key frame is decoded according to the display state data and the target decoder, to obtain a decoded video frame.

8. An image generation apparatus characterized by comprising: The image generation device comprises: A video positioning module configured to generate a target video frame of the video stream data based on an image positioning time corresponding to an image generation request for the video stream data in response to the image generation request; A display detection module configured to perform image display detection based on target pixel data of the target video frame and image detection parameters, to obtain an image detection result; An image generation module configured to generate a target display image of the video stream data based on the image detection result of the target video frame and the target video frame.

9. An image generation apparatus characterized by comprising: The image generation device comprises: One or more processors; Memory; and One or more application programs, wherein the one or more application programs are stored in the memory and configured to be executed by the processor to implement the steps of the image generation method in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, A computer program is stored thereon, and the computer program is loaded by a processor to execute the steps of the image generation method in any one of claims 1 to 7.

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