Abstract: A piston limiting structure, including: a cylinder, a piston, and a flange provided with a limiting piece, the cylinder has a piston hole perpendicular to an axial direction of the cylinder and penetrating through the cylinder, and a projection of the piston hole in a penetrating direction is circular. The piston is disposed in the piston hole in a form-fit manner and is slid in the piston hole in a reciprocating manner. A side wall of the piston is provided with a thrust groove, a bottom surface of the thrust groove forms a thrust surface on the side wall of the piston, and the thrust groove does not penetrate through two ends of the side wall of the piston along an axial length of the piston. The limiting piece abuts against the thrust surface.

Abstract: This application provides picture or audio encoding and decoding methods and apparatuses, and relates to the field of artificial intelligence (AI)—based picture or audio encoding and decoding technologies, and specifically, to the field of neural network-based picture feature map or audio feature variable encoding and decoding technologies. The encoding method includes: obtaining a to-be-encoded target, where the to-be-encoded target includes a plurality of feature elements, and the plurality of feature elements include a first feature element. The method further includes: obtaining a probability estimation result of the first feature element; determining, based on the probability estimation result of the first feature element, whether to perform entropy encoding on the first feature element; and performing entropy encoding on the first feature element only when it is determined that entropy encoding needs to be performed on the first feature element.

Abstract: Embodiments of this application disclose encoding and decoding methods, apparatuses, and devices, a storage medium, and a computer program, which relate to the field of encoding and decoding technologies. In embodiments of this application, in a decoding process, a plurality of feature points are divided into a plurality of groups based on a specified numerical value, and probability distributions of feature points in a same group are determined in parallel to improve decoding efficiency. Correspondingly, in an encoding process, the plurality of feature points are also grouped in a same grouping manner, and first image features of each group of feature points in the plurality of groups are sequentially encoded into a bit stream. To be concise, this solution can break through an efficiency bottleneck caused by serial computing when decoding is performed based on a variational auto-encoder (VAE), thereby effectively improving decoding efficiency.

Abstract: This application provides an audio/video or picture compression method and apparatus, which relates to the field of artificial intelligence (AI)-based audio/video or picture compression technologies, and to the field of neural network-based audio/video or picture compression technologies. The method includes: transforming a raw audio/video or picture to feature space through a multilayer convolution operation, extracting features of different layers in the feature space, outputting rounded feature signals of the different layers, predicting probability distribution of shallow feature signals by using deep feature signals or entropy estimation results, and performing entropy encoding on the rounded feature signals. In this application, signal correlation between different layers is utilized. In this way, audio/video or picture compression performance can be improved.

Abstract: A video frame compression method includes determining a target neural network from a plurality of neural networks according to a network selection policy; and generating, by using the target neural network, compression information corresponding to a current video frame. If the compression information is obtained by using a first neural network, the compression information includes first compression information of a first feature of the current video frame, and a reference frame of the current video frame is used for a compression process of the first feature of the current video frame. If the compression information is obtained by using a second neural network, the compression information includes second compression information of a second feature of the current video frame, and a reference frame of the current video frame is used for a generation process of the second feature of the current video frame.