Abstract: A video device, a wireless audio device and a method for performing audio and video (AV) synchronization between the video device and the wireless audio device are provided. The method includes: utilizing a controller of the video device to determine a video delay of the video device; utilizing the controller to determine an audio delay of the video device; utilizing the controller to receive information of a communications quality of the wireless audio device from the wireless audio device, to determine a wireless communications delay between the video device and the wireless audio device according to the communications quality; utilizing the controller to generate a time map information according to the video delay, the audio delay and the wireless communications delay; and transmitting the time map information from the video device to the wireless audio device for AV synchronization between the video device and the wireless audio device.

Abstract: A decoding method for audio video stream synchronization is provided. The audio video stream includes multiple clock references and multiple audio and video data packets. Each of the data packets corresponds to a presentation value. The decoding method includes: reconstructing a clock value according to a first clock reference; determining whether a difference between the clock value and a first presentation value in multiple presentation values is greater than a first range; when the difference between the clock value and the first presentation value is greater than the first range, changing the clock value to a second presentation value in the multiple presentation values; and performing at least one audio video synchronization step according to the clock value set based on the second presentation value.

Abstract: A decoding method for audio video stream synchronization is provided. The audio video stream includes multiple clock references and multiple audio and video data packets. Each of the data packets corresponds to a presentation value. The decoding method includes: reconstructing a clock value according to a first clock reference; determining whether a difference between the clock value and a first presentation value in multiple presentation values is greater than a first range; when the difference between the clock value and the first presentation value is greater than the first range, changing the clock value to a second presentation value in the multiple presentation values; and performing at least one audio video synchronization step according to the clock value set based on the second presentation value.