05267334 is referenced by 333 patents and cites 3 patents.

A method of removing frame redundancy in a computer system for a sequence of moving images. The method comprises detecting a first scene change in the sequence of moving images and generating a first keyframe containing complete scene information for a first image. The first keyframe is known, in a preferred embodiment, as a "forward-facing" keyframe or intra frame, and it is normally present in CCITT compressed video data. The process then comprises generating at least one intermediate compressed frame, the at least one intermediate compressed frame containing difference information from the first image for at least one image following the first image in time in the sequence of moving images. In a preferred embodiment, this at least one frame is known as an inter frame. Finally, detecting a second scene change in the sequence of moving images and generating a second keyframe containing complete scene information for an image displayed at the time just prior to the second scene change. This is known, in the preferred embodiment, as a "backward-facing" keyframe. The first keyframe and the at least one intermediate compressed frame are linked for forward play, and the second keyframe and the intermediate compressed frames are linked in reverse for reverse play. In a preferred embodiment, the intra frame is used for generation of complete scene information when the images are played in the forward direction. When this sequence is played in reverse, the backward-facing keyframe is used for the generation of complete scene information.

Title
Encoding/decoding moving images with forward and backward keyframes for forward and reverse display
Application Number
705345
Publication Number
5267334
Application Date
January 21, 1993
Publication Date
November 30, 1993
Inventor
Ke Chiang C Chu
Saratoga
CA, US
Daniel W Wright
Sunnyvale
CA, US
Chia L Yeh
Saratoga
CA, US
James O Normille
Sunnyvale
CA, US
Agent
Blakely Sokoloff Taylor & Zafman
Assignee
Apple Computer
CA, US
IPC
H04N 7/12
G06K 9/36
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