Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for providing a video to subscribers of a messaging system. A method includes obtaining a live video stream generated by a video source. The method also includes publishing one or more messages including one or more frames of the live video stream to a first channel of a plurality of channels. The video source is associated with the first channel.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for providing a video to subscribers of a messaging system. A method includes obtaining a live video stream generated by a video source. The method also includes publishing one or more messages including one or more frames of the live video stream to a first channel of a plurality of channels. The video source is associated with the first channel.

Abstract: Providing a video stream and metadata over channels is described. The method may include receiving a first message on a first channel of a plurality of channels, the first message encapsulating a video frame of a plurality of video frames. The method may also include generating, by a computer processing device, a second message comprising annotation metadata describing a characteristic of the video frame. The method may also include publishing the first message to a second channel of the plurality of channels and publishing the second message to a third channel of the plurality of channels.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for receiving a first message on a first channel of a plurality of channels, wherein the first message comprises a video frame of a plurality of video frames and metadata describing characteristics of the video frame. The video frame is analyzed to detect an object within the video frame. Based on the analysis, the analysis metadata indicating the analysis performed and an indication of the detected object can be generated and then encapsulated in a new message with the video frame. The new message can be published to a second channel.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for providing a video to subscribers of a messaging system. A method includes obtaining a live video stream generated by a video source. The method also includes publishing one or more messages including one or more frames of the live video stream to a first channel of a plurality of channels. The video source is associated with the first channel.

Abstract: A computer system having memory and one or more processors running an untrusted internal process determines whether the first interaction meets a first trigger condition and when the first interaction meets the first trigger condition, the computer system generates a first marker for the first data item. The computer system requests that a trusted external process perform the first interaction with the first data item and store the first marker in the database. After the first data item is stored, the computer system requests markers stored in the database and receives the first marker. The computer system determines whether an operation corresponding to the first data item is to be executed based on the first marker. When the computer system determines that a first operation corresponding to the first data item is to be executed, the computer system requests execution of the first operation.

Abstract: A server system having memory and one or more processors running a trusted internal process receives, from an untrusted external process of one or more external processes, a request to interact with a data item. In response to the request, the server system interacts with the first data item and stores a marker indicative of the interaction with the data item. After storing the marker, the server system identifies a plurality of markers corresponding to a plurality of data items and retrieves information corresponding to the plurality of markers. The retrieved information enables a determination, for each data item in the plurality of data items, as to whether an operation corresponding to the data item is to be executed. When a determination has been made that an operation corresponding to the data item is to be executed, the server system deletes the markers in conjunction with execution of the operation.