Decoding method and apparatus, coding method and apparatus, device, and storage medium

A coding method, comprising:

• constructing a candidate list of a skip mode or a direct mode:
• traversing each of prediction modes in a prediction mode candidate list in order, for each of the prediction modes, acquiring motion information of a current coding unit and a motion information index value of the skip mode or the direct mode of the current coding unit;
• performing motion compensation on the current coding unit according to the motion information of the current coding unit;
• calculating a rate distortion optimization cost corresponding to the prediction mode, comparing the rate distortion optimization cost with rate distortion optimization costs of other candidate prediction modes, and selecting a prediction mode with a smallest rate distortion optimization cost;
• carrying a motion information index value of the skip mode or the direct mode of the current coding unit corresponding to the prediction mode with the smallest rate distortion optimization cost into a bitstream;
• and
• transmitting the bitstream to a decoder-side;
• wherein the carrying the motion information index value of the skip mode or the direct mode of the current coding unit corresponding to the prediction mode with the smallest rate distortion optimization cost into the bitstream comprises:
• acquiring a number of motion vector angle prediction candidate motion information and a number of inter-prediction candidate historical motion vector prediction information;
• and
• coding the motion information index value of the skip mode or the direct mode of the current coding unit according to the number of motion vector angle prediction candidate motion information and the number of inter-prediction candidate historical motion vector prediction information and carrying the coded motion information index value into the bitstream;
• wherein the coding the motion information index value of the skip mode or the direct mode of the current coding unit according to the number of motion vector angle prediction candidate motion information and the number of inter-prediction candidate historical motion vector prediction information comprises:
• determining a maximum index value according to the number of motion vector angle prediction candidate motion information and the number of inter-prediction candidate historical motion vector prediction information;
• and
• coding, according to the maximum index value, the motion information index value of the skip mode or the direct mode of the current coding unit by using a binarization manner of truncated unary code.

A decoding device, comprising:

• at least one processor;
• and
• at least one machine-readable storage medium, wherein the at least one machine-readable storage medium stores machine-executable instructions executable by the at least one processor to:
• receive a bitstream and parse a motion information index value of a skip mode or a direct mode of a current coding unit;
• construct a candidate list of the skip mode or the direct mode;
• determine a prediction mode of the current coding unit according to the motion information index value and the candidate list of the skip mode or the direct mode of the current coding unit;
• acquire motion information of the current coding unit according to the prediction mode of the current coding unit;
• and
• perform motion compensation on the current coding unit,
• wherein the at least one processor is configured to execute the machine-executable instructions to parse the motion information index value of the skip mode or the direct mode of the current coding unit by:
• acquiring a number of motion vector angle prediction candidate motion information and a number of inter-prediction candidate historical motion vector prediction information;
• and
• determining the motion information index value of the skip mode or the direct mode of the current coding unit according to the number of motion vector angle prediction candidate motion information and the number of inter-prediction candidate historical motion vector prediction information,
• wherein the at least one processor is configured to execute the machine-executable instructions to acquire the number of motion vector angle prediction candidate motion information and the number of inter-prediction candidate historical motion vector prediction information by:
• parsing sequence-level high-level syntax to acquire the number of motion vector angle prediction candidate motion information and the number of inter-prediction candidate historical motion vector prediction information.