Patent ID: 8997161
Filing Date: 2015-03-31
Classification: G11B,H04N

Abstract:
1. A method of encoding and playing back a media file, comprising: extracting a video track from an original media file, where content is encoded in the video track; using the encoded content to encode a tricky-play track configured to enable the visual-search of the video track, where encoding the tricky-play track includes encoding at least one key frame that corresponds to a frame in the encoded content that is not a key frame and where the distance between key frames in the encoded content is not uniform; requesting portions of the encoded content from a media server using HTTP using a playback device; playing back a portion of the compressed video track using the playback device; receiving a trick-play request using the playback device; determining, in response to the received trick-play request, a position in the trick-play track corresponding to the position of the compressed video track being played using a first index using the playback device; playing back a portion of the trick-play track starting from the determined position in the trick-play track using the playback device; receiving a normal-play request using the playback device; determining, in response to the received normal-play request, a position in the compressed video track corresponding to the position of the trick-play track being played using a second index using the playback device; locating a key frame with the closest timestamp preceding the determined position in the compressed video track; recursively decoding the located key frame and decoding the difference frames between the located key frame and the difference frame at the determined position in the compressed video track; and playing back a portion of the compressed video track starting from the difference frame at the determined position in the compressed video track.