Smooth scanning presenter
View Patent ↗Described herein is a technology for the presentation digital video. One implementation, described herein, smoothly presents variable-speed scanning of a compressed digital video stream—for example, a MPEG video stream. One implementation, described herein, smooth scanning (e.g., fast-forward and fast-rewind) video is produced by selectively displaying certain types of frames of a Group-of-Pictures (GOP). The scope of the present invention is pointed out in the appending claims.
1. A computer-readable medium having computer-executable instructions that, when executed by a computer, performs a method comprising:
selecting frames of a Group-of-Pictures (GOP) of a MPEG digital video for presentation and frames of the GOP for non-presentation, wherein the non-presentation frames are selected in the following order:
one or more B-frames;
one or more P-frames, only if all B-frames of the GOP are also selected for non-presentation;
presenting the selected presentation frames of the GOP.
2. A medium as recited in claim 1 , wherein the method further comprises obtaining one or more GOPs of the MPEG digital video.
3. A medium as recited in claim 1 , wherein the presenting comprises sending the selected presentation frames of the GOP over a communications medium.
4. A medium as recited in claim 1 , wherein the method further comprises obtaining a variable scan-rate indicator.
5. A medium as recited in claim 1 , wherein the method further comprises:
obtaining a variable scan-rate indicator;
varying the selecting in response to such indicator.
6. A medium as recited in claim 1 , wherein the method further comprises:
obtaining a variable scan-rate indicator;
determining ratio of non-presentation frames to presentation frames relative to the variable scan-rate indicator;
wherein the selecting of frames is based upon such ratio.
7. A presentation device comprising:
an audio/visual output;
a medium as recited in claim 1 .
8. A computer-readable medium having computer-executable instructions that, when executed by a computer, performs a method comprising:
selecting frames of a Group-of-Pictures (GOP) of a MPEG digital video for presentation and frames of the GOP for non-presentation, wherein the selected non-presentation frames are selected from a group consisting of B-frames and P-frames such that P-frames are selected only if all B-frames are also selected for non-presentation;
presenting the selected presentation frames of the GOP.
9. A medium as recited in claim 8 , wherein the method further comprises obtaining one or more GOPs of the MPEG digital video.
10. A medium as recited in claim 8 , wherein the presenting comprises sending the selected presentation frames of the GOP over a communications medium.
11. A medium as recited in claim 8 , wherein the method further comprises:
obtaining a variable scan-rate indicator;
varying the selecting in response to such indicator.
12. A presentation device comprising:
an audio/visual output;
a medium as recited in claim 8 .
13. A method comprising:
selecting frames of a Group-of-Pictures (GOP) of a MPEG digital video for presentation and frames of the GOP for non-presentation, wherein the selected non-presentation frames are selected from a group consisting of B-frames or P-frames such that P-frames are selected only if all B-frames are also selected for non-presentation;
presenting the selected presentation frames of the GOP.
14. A method as recited in claim 13 further comprising obtaining one or more GOPs of the digital video.
15. A method as recited in claim 13 further comprising:
obtaining a variable scan-rate indicator;
varying the selecting in response to such indicator.