User interface for retiming in a media authoring tool

• US 9,014,544 B2
• Filed: 12/19/2012
• Issued: 04/21/2015
• Est. Priority Date: 12/19/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Wang, Xiaohuan C., Meaney, Brian, Stern, Michael P., Sundaram, Vijay
• Primary Examiner(s): Tran, Thai
• Assistant Examiner(s): MESA, JOSE M
• Application Number:
  US13/720,988
• Publication Number:
  US 20140169765A1
• Time in Patent Office: 853 Days
• Field of Search: 386/241, 386/248, 386/343, 386/350
• US Class Current: 386/280
• CPC Class Codes: G11B 27/005 Reproducing at a different information rate from the information rate of recording for television signals H04N5/783
• CPC Class Codes: G11B 27/031 Electronic editing of digitised analogue information signals, e.g. audio or video signals
• CPC Class Codes: G11B 27/34 Indicating arrangements indicating means incorporated in magazine or cassette G11B23/046 and G11B23/0875; indicating measured values in general G01D
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 9/79 Processing of colour television signals in connection with recording

Abstract

A novel method for creating multimedia presentations in a media editing application is provided. The method selects a portion of a media clip and retimes the selected portion of the media clip from a first playback speed to a second playback speed. The method defines a transition interval for a discontinuity between a first section of the media clip with the first playback speed and a second section of the media clip with the second playback speed. The media clip is played back according to a smoothed curve that is constrained by the transition interval, the first playback speed, and the second playback speed. The smoothed curve transitions gradually from the first playback speed at the start of the transition interval to the second playback speed at the end of the transition interval.

Claims

1. A method for creating a multimedia presentation, the method comprising:

receiving a media clip for the multimedia presentation, the media clip comprising a first section having a first playback speed and a second section having a second playback speed, the first section transitioning to the second section at a user-defined point of discontinuity;

defining a transition interval encompassing the user-defined point of discontinuity, wherein the start of the transition interval is after the start of the first section and the end of the transition interval is before the end of the second section;

presenting the transition interval in a graphical user interface (GUI), wherein boundaries of the transition interval are presented as a plurality of user-selectable items for adjusting a duration of the transition interval; and

playing back the media clip according to a curve that is constrained by the transition interval, the first playback speed, and the second playback speed.

2. The method of claim 1, wherein the curve transitions gradually from the first playback speed at the start of the transition interval to the second playback speed at the end of the transition interval.

3. The method of claim 1, wherein the curve is a playback curve for specifying a playback timing of the media clip.

4. The method of claim 1 further comprising defining a discontinuity keyframe at the user-defined point of discontinuity.

5. The method of claim 4, wherein the curve is not constrained to go through the discontinuity keyframe.

6. The method of claim 1 further comprising:

selecting a portion of the media clip; and

retiming the selected portion of the media clip from the first playback speed to the second playback speed, wherein the selected portion is the second section and an unselected portion is the first section.

7. A method of defining a media editing application for creating multimedia presentations, the method comprising:

defining a range selector for user-selecting a portion of a media clip in a multimedia presentation by a user;

defining a retiming engine for applying a retiming operation that changes a playback timing of the media clip from a first playback speed to a second playback speed at a first transition point that is at an intersection of the selected portion and an unselected portion; and

defining a transition engine for determining a playback speed of the media clip around the first transition point by defining second and third transition points, the second transition point earlier than the first transition point by a fraction of the duration of the selected portion and the third transition point later than the first transition point by a fraction of the duration of the unselected portion.

8. The method of claim 7, wherein the playback speed of the media clip gradually changes from the first playback speed at the second transition point to the second playback speed at the third transition point without overshooting the second playback speed before the third transition point.

9. The method of claim 7, wherein the playback speed of the media clip at the second transition point is the first playback speed.

10. The method of claim 9, wherein the playback speed of the media clip at third transition point is the second playback speed.

11. The method of claim 10, wherein the playback speed of the media clip at the first transition point is between the first playback speed and the second playback speed.

12. The method of claim 7, wherein the transition engine determines the playback speed of the media clip by defining a playback curve that specifies a relationship between content of the media clip and the playback timing of the media clip.

13. The method of claim 7, wherein the retiming engine applies a retiming operation by defining a keyframe associated with the first transition point, wherein the keyframe defines a particular point in the content of the media clip that is played back at a particular playback time.

14. A system comprising:

a set of processing units for executing sets of instructions; and

a non-transitory machine readable medium storing a media editing application for execution by at least one of the processing units, the media editing application comprising sets of instructions for;

editing a playback curve of a media clip of a multimedia presentation for specifying playback timing of the media clip, wherein editing the playback curve comprises changing a playback speed of a section of the playback curve;

introducing a transition interval at a user-adjustable point of discontinuity between a first section with a first playback speed and a second section with a second playback speed, wherein the playback speed of the media clip gradually changes without any discontinuity from the first playback speed at a start of the transition interval to the second playback speed at an end of the transition interval without crossing the second playback speed before the end of the transition interval; and

playing back the media clip according to the edited playback curve and the transition interval.

15. The system of claim 14, wherein introducing the transition interval comprises determining a first fraction of a duration of the first section and a second fraction of a duration of the second section.

16. The system of claim 14 further comprising a storage for storing the playback curve, wherein a data structure of the playback curve stores the start point and the end point for the transition interval.

17. The system of claim 16, wherein the data structure stores a plurality of keyframes, each keyframe defining a particular point in the content of the media clip that is played back at a particular playback time.

18. The system of claim 14, wherein playing back the media clip according to the edited playback curve comprises creating a smoothed playback curve, the smoothed playback curve comprising a Bezier curve that is constrained at the first playback speed at the start of the transition interval and at the second playback speed at the end of the transition interval.

19. The system of claim 18, wherein the user-adjustable point of discontinuity is a keyframe that anchors the end of the first section and the start of the second section, wherein the playback curve is not constrained to go through the keyframe.

20. A non-transitory computer readable medium storing a computer program for execution by one or more processing units, the computer program comprising sets of instructions for:

receiving a media clip that changes playback timing from a first playback speed to a second playback speed at a first transition point between a first media clip section and a second media clip section;

introducing a transition interval that is defined by a second transition point and a third transition point, the second transition point earlier than the first transition point and the third transition point later than the first transition point in the media clip, wherein the second and third transition points are user-selectable items that are adjustable within a graphical user interface (GUI); and

determining the playback speed of the media clip around the first transition point based on a playback time of the second and third transition points.

21. The non-transitory computer readable medium of claim 20, wherein the program further comprises a set of instructions for displaying a speed indicator for indicating the playback speed of the media clip.

22. The non-transitory computer readable medium of claim 21, wherein the speed indicator is partitioned into a plurality of sections based on transitions of playback speeds in the media clip.

23. The non-transitory computer readable medium of claim 22, wherein one of the plurality of sections is a transition section that starts at the second transition point and ends at the third transition point.

24. The non-transitory computer readable medium of claim 23, where the transition section is associated with said user-selectable items.

25. The non-transitory computer readable medium of claim 20, wherein the second transition point is initially defined to be earlier than the first transition point by a fraction of the duration of the first media clip section and the third transition point is initially defined to be later than the first transition point in the media clip by a fraction of the duration of the second media clip section.

26. The non-transitory computer readable medium of claim 20, wherein the playback speed of the media clip gradually changes from the first playback speed at the second transition point to the second playback speed at the third transition point.

27. The non-transitory computer readable medium of claim 20, wherein the set of instructions for determining the playback speed of the media clip comprises a set of instructions for defining a playback curve that specifies a relationship between the content of the media clip and the playback timing of the media clip.