A system clock reference is transmitted to user devices over a short range communication channel and used to calculated a clock offset. The clock offset is stored together with a user identifier in a server memory, from which the clock offset can be retrieved when receiving the user identifier together with a video stream of video frames tagged with respective timestamps. The timestamps are converted into capture times according to a system clock using the retrieved clock offsets. Video streams from multiple user devices thereby have video frames timestamped using a same clock reference and can be time aligned.

The present disclosure provides a video jitter detection method and an apparatus. The video jitter detection method includes: acquiring a video; inputting the video into a detection model to obtain an evaluation value of the video, where the evaluation value is used to indicate a degree of jitter of the video; where the detection model is a model obtained by training using video samples in a video sample set as inputs and evaluation values of the video samples in the video sample set as outputs. By inputting the video to be detected into the detection model, the evaluation value of the video can be acquired through the detection model, thereby whether the video is jittery is determined, which realizes the video jitter detection end-to-end, and improves the detection accuracy and robustness of video jitter.

A signage player includes: a time function configured to count an internal device time. The signage player also includes a time correction calculator configured to acquire a reference time from the outside, for example, an NTS server, at a timing determined in advance and synchronize the internal device time with the reference time; and a time corrector configured to calculate a time correction coefficient defined using a change rate of a time difference, an error change rate (Δ) between the reference time and the internal device time at a timing different from the timing determined in advance and calculate a corrected time acquired by correcting the internal device time using the time correction coefficient.

A moving image distribution server 12 transfers, by streaming, data of a plurality of moving images representing the same space. A moving image reproduction apparatus 10 separates audio data from any one of the moving images and outputs the audio data after a predetermined period of delay. The moving image reproduction apparatus 10 also separates image data from another moving image and outputs the image data in synchronization with audio. When a user performs an image switching operation, the moving image reproduction apparatus 10 acquires data of a moving image that has been switched from another moving image, separates image data therefrom, and starts outputting the image data given the same PTS as the audio data continuously being output.

A system includes a primary playback system and a secondary playback system. The primary playback system plays back selected content. The secondary playback system monitors progress of the primary playback system playing back the content. Based on detected progress, the secondary playback system synchronizes playback of supplemental media (such as descriptive audio, closed caption text, etc.) associated with the content on a secondary playback system operated by a user. In response to detecting a scheduled advertisement window during playback of the content on the primary playback system, the secondary playback system discontinues playback of the supplemental media associated with the content on the secondary playback system. During or after playback of the advertisement on the primary playback system, the secondary playback system monitors playback of the selected content by the primary playback system to re-synchronize playback of supplemental media to the playback of the content on the secondary playback system.

Some aspects include a method for synchronizing at least two devices, including: connecting the at least two devices using an application executed on each of the at least two devices, wherein: a same media is executed in synchronization by the at least two devices using the application; and an input received by the application executed on a first device of the at least two devices actuates a same response on the at least two devices.

The signal processing device according to an embodiment of the present disclosure includes: a frame buffer to store an input image and output an output image, an output synchronization signal calculator to calculate an output synchronization signal based on an input synchronization signal and a size or a position of the output image in comparison with the input image, and an output synchronization signal output interface to output a variable output synchronization signal of which a start timing changes based on a signal from the output synchronization signal calculator, wherein a difference between a start timing of the input synchronization signal and a start timing of the output synchronization signal changes based on the size of the output image. Accordingly, a delay time may be reduced in response to the output image having a size different from a size of the input image being output.

Techniques are disclosed for managing media playback among an ad hoc group of playback devices. Such techniques may involve building a session among the playback devices in which playback devices communicate information regarding their playback capabilities. Based on the playback capabilities of the devices, playback mode may be derived for the session. Playback operations may be synchronized among the devices that are members of the session, in which devices receive identification of asset(s) to be rendered pursuant to the playback operation and timing information of playback of the asset. The devices may stream the playback assets directly from media sources when they are capable of doing so. In this manner, communication resources are conserved.

Techniques are disclosed for managing media playback among an ad hoc group of playback devices. Such techniques may involve building a session among the playback devices in which playback devices communicate information regarding their playback capabilities. Based on the playback capabilities of the devices, playback mode may be derived for the session. Playback operations may be synchronized among the devices that are members of the session, in which devices receive identification of asset(s) to be rendered pursuant to the playback operation and timing information of playback of the asset. The devices may stream the playback assets directly from media sources when they are capable of doing so. In this manner, communication resources are conserved.

The present invention provides a method, a device and a computer-readable medium for a pseudo seamless switch between different video sources and belongs to a field of the Internet technology. According to the method, a device and a computer-readable medium for a pseudo seamless switch between different video sources of the present invention, when a video source needs to be switched, the Web browser first establishes a target video source playback instance; determines a synchronization duration based on a playing state of an original video source and a network state; after the synchronization duration, the Web browser switches to the target video source playback instance to achieve seamless switching between various video sources, so as to effectively avoid blocking during playback and greatly improve user experience. And the method, device and computer-readable medium for a pseudo seamless switch between different video sources of the present invention have the advantages of simple implementation, low application cost and wide application range.