公开(公告)号：US20220109866A1

公开(公告)日：2022-04-07

申请号：US17491944

申请日：2021-10-01

Applicant: Apple Inc.

Inventor： Zeina SINNO ,  Steven E. SAUNDERS

IPC: H04N19/46 ,  H04N19/154 ,  H04N19/176 ,  H04N17/00

Abstract: Techniques are presented for inserting markers into a video stream. For each frame of an encoded video stream, disclosed techniques determine a structure of macroblocks from a code of the frame, and then, select macroblocks to be replaced from the determined structure of macroblocks. Inserting a marker into a frame carried out by replacing codes of the selected macroblocks with a code of a marker that identifies the frame. Marking frames of the video stream facilitates finding correspondence between frames from the video stream before transmission over a channel and the video stream received from the channel, based on the inserted markers. Knowledge of frame correspondence enable a video quality metric estimation based on a comparison between the found corresponding frames.

公开(公告)号：US20200314467A1

公开(公告)日：2020-10-01

申请号：US16814278

申请日：2020-03-10

Applicant: Apple Inc.

Inventor： Simon GOLDREI ,  Steven E. SAUNDERS ,  Roger N. PANTOS ,  John MATIENZO

IPC: H04N21/2389 ,  H04N21/24 ,  H04N21/2187 ,  H04N21/8358 ,  H04N21/234 ,  H04N21/233 ,  H04N21/845

Abstract: Techniques are disclosed for measuring propagation delay of a media distribution system based on content output by rendering devices. An output from an output device of the media distribution system may be captured and a token may be detected from the captured content. A timecode may be derived from the detected token. The system's propagation delay may be determined from the derived timecode and may provide a basis to analyze system delays and other processing artifacts. In this manner, propagation artifacts may be estimated between multiple rendering devices that lack controls to synchronize their operation.