Video encoder and video decoder

A video decoder configured to determine whether compressed data of an input frame include three-dimensional (3D) index data and accordingly determine how to generate a late frame, wherein:

• the input frame is an early frame or the late frame;
• the video decoder includes a decoding circuit, a decision circuit, a frame conversion circuit, and a reconstruction circuit;
• the decoding circuit is configured to decompress compressed data of the early frame to generate the early frame, or configured to use a previous frame previously generated by the video decoder as the early frame;
• the decision circuit is configured to determine whether the compressed data of the input frame includes the 3D index data and accordingly generate a decision result;
• the frame conversion circuit is coupled with the decoding circuit and the decision circuit, and is configured to generate a conversion frame according to the early frame and the 3D index data after the decision result indicates that the compressed data of the input frame includes the 3D index data;
• and
• the reconstruction circuit is configured to reconstruct the late frame according to the conversion frame and compressed data of the late frame after the frame conversion circuit generates the conversion frame.