Abstract: This disclosure provides a method, device and a computer program product for managing metadata of a file system. The method may include: determining a data structure of the metadata based on a type of the file system; deriving a reference value for a first field of the metadata based on the data structure of the metadata and a protocol of the file system; and overwriting the first field of the metadata with the reference value in response to an actual value of the first field of the metadata being not equal to the reference value and there being no backup for the metadata.

Abstract: This disclosure provides a method, device and a computer program product for managing metadata of a file system. The method may include: determining a data structure of the metadata based on a type of the file system; deriving a reference value for a first field of the metadata based on the data structure of the metadata and a protocol of the file system; and overwriting the first field of the metadata with the reference value in response to an actual value of the first field of the metadata being not equal to the reference value and there being no backup for the metadata.

Abstract: The present disclosure provides a method and device for encrypting or decrypting a video file. The method for encrypting the video file includes: generating index information and video information for each of a plurality of frames of a video file to be encrypted based on video data for each of the plurality of frames; encapsulating the index information and the video information for each of the plurality of frames into an encapsulation format of the video file; and encrypting, for one or more frames of interest among the plurality of frames, the index information in the encapsulation format of the video file using a key.