Synamedia Limited

Techniques for watermarking at the edge in a low latency content delivery system are described herein. In various embodiments, an edge relay server, which includes one or more processors and non-transitory memory, announces a watermarked video track for a media stream. The edge relay server obtains from a client device a watermark identifier associated with a request for the watermarked video track. The edge relay server, in response to receiving the request, subscribes to one or more video tracks in order to receive units in the one or more video tracks representing the media stream. The edge relay server further constructs the watermarked video track using the units according to the watermark identifier and sends to the client device the watermarked video track.

Techniques for selecting TV user interface (UI) transition characteristics are described. In accordance with various embodiments, a transition characteristics selection method is performed at a device (e.g., a cloud UI engine on a server) with one or more processors and a non-transitory memory. The UI engine receives a request for transitioning from a first screen to a second screen on a client device while in a real-time content presentation mode. In response to receiving the request and while in the real-time content presentation mode, the UI engine obtains one or more presentation conditions of the client device and selects one or more transition characteristics for transitioning from the first screen to the second screen based on costs associated with the one or more transition characteristics and the one or more presentation conditions.

Techniques for multi-stream content delivery are described herein. In various embodiments, at least one server hosting a cloud computing platform renders a user interface for a client device, where the user interface includes low latency content and buffered content. The server then identifies display properties of the buffered content in the user interface and encodes the low latency content into a low latency stream. The server also streams the user interface to the client device, including transmitting to the client device the low latency stream, separate and distinct from a buffered content stream for delivering the buffered content to the client device. The server additionally signals the client device the display properties of the buffered content for playback of the low latency stream and the buffered content at the client device.

Techniques for measuring cloud-based input latency are described herein. In accordance with various embodiments, a server including one or more processors and a non-transitory memory receives from a client an input event corresponding to a request for a TV user interface (UI). The server adds a tag to each of a set of screens corresponding to the TV UI and records event data corresponding to the input event prior to rendering the set of screens into a set of rendered frames. The server additionally decodes the tag in the set of rendered frames to generate metadata that associate the event data with the set of rendered frames prior to encoding the set of rendered frames into a set of encoded frames. The server also transmits to the client the set of encoded frames and the metadata.

A method of selectively decrypting encrypted data may include selecting a plurality of encrypted data bits between and including a first encrypted data bit and a last encrypted data bit; for each encrypted data bit from the plurality of encrypted data bits: determining a corresponding encrypted block and a block number that contains the encrypted data bit, determining a corresponding counter for the determined block number, determining a bit position of the encrypted data bit within the determined encrypted block, selecting a counter bit at the bit position within the counter, encrypting the counter, and executing an XOR operation between the encrypted data bit and the corresponding encrypted counter bit.

Various embodiments include facilitating video playback, based on an HTML iframe and a headless browser. To that end, in some embodiments, a method is performed at a first device, which may be referred to as a receiving device. The first device includes a processor, a non-transitory memory, and a communication interface. The communication interface enables commutation with a second device, which may be referred to as a sending device. The method includes receiving the HTML iframe from the second device. The HTML iframe may include a video tag, or the video tag may be nested in another HTML iframe. Moreover, the method includes playing a video stream that is identified by the video tag. Playing the video stream includes executing the HTML iframe via the headless browser to retrieve the video stream based on the video tag, and transmitting the video stream to a display device.

Techniques for synchronized interleaved watermarking are described. In various embodiments, a headend provisions control words (CWs), generates entitlement control messages (ECMs) for producing the CWs, where each of the ECMs is associated with a watermark identifier (WMID) symbol index assigned to a watermark cryptoperiod, moves portion(s) from a video stream to auxiliary streams, generates versions of the portion(s) to embed watermark symbols within the watermark cryptoperiod, where each version represents a respective watermark symbol, and encrypts the versions using the CWs at start of the watermark cryptoperiod. On the client side, a client device storing a WMID obtains the video and encrypted auxiliary streams and the ECMs referencing the WMID symbol index and selects and decrypts an auxiliary stream using a CW during the watermark cryptoperiod based on the respective watermark symbol, the WMID symbol index, and the WMID before re-multiplexing the video and auxiliary streams for rendering.

Techniques for measuring cloud-based input latency are described herein. In accordance with various embodiments, a server including one or more processors and a non-transitory memory receives from a client an input event corresponding to a request for a TV user interface (UI). The server adds a tag to each of a set of screens corresponding to the TV UI and records event data corresponding to the input event prior to rendering the set of screens into a set of rendered frames. The server additionally decodes the tag in the set of rendered frames to generate metadata that associate the event data with the set of rendered frames prior to encoding the set of rendered frames into a set of encoded frames. The server also transmits to the client the set of encoded frames and the metadata.

Techniques for switching a client device to play low latency content are described. In accordance with various embodiments, the client device switching method is performed at a device (e.g., a client device) with a processor and a non-transitory memory. The client device detects a request for a user interface (UI) while playing a media content item from a buffer and sends to a server the request and status of playing the media content item from the buffer. The client device then receives from the server a switch point determined by the server based at least in part on the status and the requested UI. The client device further determines whether the buffer has sufficient UI frames rendered by the server at the switch point. Upon determining that the buffer has sufficient UI frames, the client device switches to playing the UI frames from the buffer at the switch point.

Techniques for selecting TV user interface (UI) transition characteristics are described. In accordance with various embodiments, a transition characteristics selection method is performed at a device (e.g., a cloud UI engine on a server) with one or more processors and a non-transitory memory. The UI engine receives a request for transitioning from a first screen to a second screen on a client device while in a real-time content presentation mode. In response to receiving the request and while in the real-time content presentation mode, the UI engine obtains one or more presentation conditions of the client device and selects one or more transition characteristics for transitioning from the first screen to the second screen based on costs associated with the one or more transition characteristics and the one or more presentation conditions.