Abstract:
A computer-implemented method includes displaying, within a user interface in a digital media system, a thumbnail representing at least a portion of a media clip, receiving user input corresponding to a play speed at which a media clip is to be played, determining whether the received user input exceeds one or more predetermined thresholds, and selectively disabling playing of a video portion or an audio portion, or both, based on a result of the determination.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of and claims the benefit of priority to U.S. patent application Ser. No. 11/771,724, filed on Jun. 29, 2007, which claims the benefit of priority to U.S. Provisional Application Ser. No. 60/871,758, filed on Dec. 22, 2006, and entitled “Modified Media Presentation During Scrubbing”, the benefit of priority of each of which is claimed hereby, and each of which are incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     In general, this document describes systems and techniques for editing video clips using video editing software. 
     BACKGROUND 
     Scenes in motion can be captured and recorded using a variety of devices ranging from state-of-the-art professional video cameras used in television and movie-making to simple cameras on cellular telephones. Some of the devices that can be used to capture motion pictures, including digital camcorders and digital cameras, also allow storing the captured images in digital format including the moving picture experts group. (MPEG) format. Depending on device capabilities and user settings, a camera can capture and store both audio and video. The recorded information is automatically stored in digital format and can be easily transported to secondary devices including hard disks in computers using various wired or wireless communications protocols such as bluetooth or universal serial bus (USB) based devices. 
     Video editing software, such as iMovie HD 6.0.1, provides a user in possession of a large repository of video clips with non-linear editing techniques to edit raw footage. Such editing includes cutting segments of the footage, re-arranging segments of the same video clip, re-arranging and combining segments of multiple video clips, and modifying the content by adding content including audio tracks, voice-overs, titles, and transitions between frames. Software manufacturers regularly add features to the software so that the software is simple to operate for an average user, while providing a near-professional quality to the finished video. 
     SUMMARY 
     In one example, based on user input, a system can upload a library of video clips, display the video clips as a series of thumbnails in a user interface, provide previews of specific time instants in a video clip, and allow a user to edit the content of video clips displayed in the user interface. 
     In one implementation, a computer-implemented method is described. The method includes displaying, within a user interface in a digital media system, a thumbnail representing at least a portion of a media clip, receiving user input corresponding to a play speed at which a media clip is to be played, determining whether the received user input exceeds one or more predetermined thresholds, and selectively disabling playing of a video portion or an audio portion, or both, based on a result of the determination. 
     This and other aspects can include one or more of the following features. Both the video portion playing and the audio portion playing can be enabled if the play speed is determined to be less than or equal to a first threshold. The audio portion playing can be disabled and the video portion playing can be enabled if the play speed is determined to be greater than the first threshold and less than or equal to the second threshold. Both the video portion playing and the audio portion playing can be disabled if the play speed is determined to be greater than the second threshold. Playing can cease when user input corresponding to the play speed is stopped. The user input can comprise moving a cursor over the thumbnail at a speed. The cursor can be moved to play the media clip in one of a forward and a reverse direction. The cursor can be moved at a speed based on user input. Moving the cursor can further include determining a direction of movement of the cursor and disabling playing of the video portion and the audio portion if the direction of movement is determined to be substantially vertical, regardless of the speed of the cursor. 
     In another implementation, a medium bearing instructions to enable one or more machines to perform operations is described. The operations include displaying, within a user interface in a digital media system, a thumbnail representing at least a portion of a media clip, receiving user input corresponding to a play speed at which a media clip is to be played, determining whether the received user input exceeds one or more predetermined thresholds, and selectively disabling playing of a video portion or an audio portion, or both, based on a result of the determination. 
     This and other aspects can include one or more of the following features. Both the video portion playing and the audio portion playing can be enabled if the play speed is determined to be less than or equal to a first threshold. The audio portion playing can be disabled and the video portion playing can be enabled if the play speed is determined to be greater than the first threshold and less than or equal to the second threshold. Both the video portion playing and the audio portion playing can be disabled if the play speed is determined to be greater than the second threshold. Playing can cease when user input corresponding to the play speed is stopped. The user input can comprise moving a cursor over the thumbnail at a speed. The cursor can be moved to play the media clip in one of a forward and a reverse direction. The cursor can be moved at a speed based on user input. Moving the cursor can further include determining a direction of movement of the cursor and disabling playing of the video portion and the audio portion if the direction of movement is determined to be substantially vertical, regardless of the speed of the cursor. 
     The systems and techniques described here may provide one or more of the following advantages. First, the video clips in a video library can be viewed as rows of horizontal thumbnails, where a thumbnail can represent all or portion of a time period of the video clip. The thumbnails are wrapped within the viewable window of the user interface to avoid horizontal scrolling within the window to access segments of the video clip. The video clips appear to a user in the form of a two-dimensional time line. Second, a frame corresponding to a time instant in a video clip can be previewed by simply placing a cursor on a display device operated by a pointing device, such as a mouse, at a desired position on a thumbnail related to the video clip. In a system where the pointing device is a mouse, multiple frames in a video clip can be previewed by a simple mouse over without the need to click the mouse at any point on the user interface. In selecting segments of video during editing, a user can use this feature to determine start and stop points in the video clip. Third, a segment of desired length can be chosen from a video clip and isolated from the remainder of the video clip for use in editing. In a manner similar to selecting text in a text editor, a user can select one or more desired segments of a video clip. Subsequently, the user can transfer the one or more selected segments to a separate portion of the user interface to edit the content of the segments. The selected segments can be transferred using a pointing device, such as a mouse, without the need to click the mouse at any point in the selected segment. Fourth, a user can anchor a specific point in additional content overlaid on recorded video, including audio tracks, voice-overs, titles, and transitions between frames, to a specific point in the content of the video clip. In this manner, the user can synchronize the start time of playback of the overlay content to the content of the video clip regardless of additions to or deletions from the video clip. The user may be assured that once overlay content has been anchored at a desired position, such content will always playback in the finished video clip at the anchored position regardless of other modifications that the user may perform on the video clip. 
     In addition, the system can simplify the video editing process and make it user-friendly. Since the tediousness involved in editing is significantly reduced, a user is encouraged to perform improved editing operations on the video content. The quality of the finished video and the confidence of the user in video editing can simultaneously be improved. 
     The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is an example of a schematic of a user interface to perform video editing. 
         FIG. 2A  is an example of a schematic of a user interface displaying each video clip as a thumbnail. 
         FIG. 2B  is an example of a schematic of a user interface displaying a video clip as a thumbnail group. 
         FIG. 3  is an example of a schematic of a user interface displaying a plurality of video clips as corresponding thumbnail groups. 
         FIG. 4A  is an example of a schematic of a first frame in a video clip corresponding to a first position of a playhead. 
         FIG. 4B  is an example of a schematic of a second frame in a video clip corresponding to a second position of a playhead. 
         FIG. 4C  is an example of a schematic of a third frame in a video clip corresponding to a third position of a playhead. 
         FIG. 4D  is an example of a schematic of a fourth frame in a video clip corresponding to a fourth position of a playhead. 
         FIG. 4E  is an example of a schematic of a fifth frame in a video clip corresponding to a fifth position of a playhead. 
         FIG. 5  is an example of a schematic of segments of video content selected from the media pane and transferred to the project pane. 
         FIG. 6  is an example of overlay content anchored to video content in a project pane. 
         FIG. 7  is an example of a flow chart of a method of displaying video clips as a series of one or more thumbnails in a thumbnail group. 
         FIG. 8  is an example of a flow chart of a method of previewing a frame corresponding to a time instant in a video clip. 
         FIG. 9  is an example of a flow chart of a method of scrubbing based on a play speed. 
         FIG. 10  is an example of a flow chart of a method of synchronizing overlay content to video content. 
         FIG. 11  is an example of a schematic of a system on which the video editing software is implemented. 
         FIG. 12  is an example of a schematic of a central processing unit. 
     
    
    
     Like reference symbols in the various drawings indicate like elements. 
     DETAILED DESCRIPTION 
       FIG. 1  depicts an example of a schematic of a user interface  100  to perform video editing. The user interface  100  includes a media pane  105 , a project pane  110 , and a preview pane  115 . Video clips containing raw footage recorded using a recording instrument are uploaded into the user interface  100  and displayed in the media pane  105 . In some implementations, the video clips containing raw footage may be stored on a storage device such as a video library. When the user interface is opened, the system can display the available video libraries in a pane adjacent to the media pane  105 . In other implementations, when the user interface is opened, the system can automatically search the storage device for video clips and display all available video clips in the media pane  105 . In other implementations, the system can retrieve stored video clips based on user input. All video clips selected by the user can be uploaded into the user interface  100  and displayed in the media pane  105  regardless of the type of the video clip or the recording instrument. The video clips can be recorded using any recording instrument including digital camcorders, digital cameras, and cellular telephones. The video clips can be stored in any format including quicktime, mpeg-1, mpeg-2, AVI, and real video. In addition, the time period of each video clip can be displayed on or adjacent to a corresponding video clip. 
     The project pane  110  includes one or more segments from one or more of the video clips displayed in the media pane  105  that can be selected by the user for editing. When segments are selected and transferred from the media pane  105  to the project pane  110 , a project is automatically created. In some implementations, a pane displaying projects can be displayed adjacent to the project pane  110 . Subsequent to editing, the contents of a project pane  110  can be saved as a finished project. A finished project can be saved in any format including quicktime, AVI, mpeg-1, mpeg-2, and real, regardless of the format of the video from which each segment in the project was obtained. A saved project can be re-opened for further editing. In addition, the project pane  105  can also include representations to indicate additional content including audio tracks, voice-overs, titles, and transitions between frames. 
     Video in a video clip is stored as a sequence of frames. The preview pane  115  displays frames, wherein a frame is one of the plurality of photographic images in a motion picture. A frame displayed in the preview pane  115  corresponds to a time instant in the video clip. The preview pane  115  can display frames corresponding to content displayed in the media pane  105  and content displayed in the project pane  110 . In addition, the preview pane  115  plays back video content displayed in the media pane  105  and in the project pane  110 , based on user input. Based on system capabilities, the content played back in the preview pane  115  can include audio content recorded along with the video content or added to the raw footage. A user can preview the effect of editing the video content in the preview pane  115 . 
     In some implementations, the width of the media pane  105  is equal to the sum of the widths of the project pane  110  and the preview pane  115 . The height of the three panes can be equal to one another. A user can alter the dimensions of the panes within the limits of the dimensions of a display device on which the user interface  100  is displayed. The dimensions of the user interface  100  can also be altered within the limits of the display device causing the dimensions of the panes to change proportionally. 
     In some implementations, the media pane  105  can be displayed in the bottom half of the user interface  100  and the project pane  110  and the preview pane  115  can be displayed in the top half. Alternatively, the media pane  105  can be displayed in the top half and the project pane  110  can be displayed in the bottom half. The positions of the media pane  105  and the project pane  110  within the user interface  100  can be switched in a single operation. For example, the media pane  105  may display video clips from the video library. The project pane  110  may display segments from one or more video clips selected by the user. The preview pane  115  may display a frame corresponding to a time instant determined by the position of the cursor on the display device. Upon receiving input from a user, in a one-step operation, the positions of the media pane  105  and the project pane  110  can be simultaneously swapped while retaining the content displayed in the media pane  105  and the project pane  110 . 
       FIG. 2A  depicts an example of a schematic of a user interface  100  displaying each video clip  200  as a thumbnail. A video clip  200  includes the content recorded by a recording instrument from the instant the recording feature is turned on to the instant the recording feature is turned off. When the video clips  200  in a video library are uploaded into the user interface  100 , each video clip  200  is displayed as one or more rows of rectangular thumbnails. The time line of a video clip  200  runs from left to right and top to bottom. In some implementations, each video clip  200  can be represented by a single rectangular thumbnail with a system defined distance separating each thumbnail to distinguish between video clips. Thumbnails are displayed in a first row until the sum of the widths of the thumbnails exceed the width of the media pane  105  displayed. Subsequent thumbnails are wrapped to the next row in the media pane  105 . A gutter, which is a system designated space, separates two rows of thumbnails. 
       FIG. 2B  depicts an example of a schematic of a user interface  100  displaying a video clip  200  as a thumbnail group  203 . The thumbnail group  203  collectively representing the video clip is displayed as a continuous sequence of one or more rectangular thumbnails  205 . The vertical and horizontal dimensions of each thumbnail  205  are designated by the system. Each video clip  200  is collectively represented by a thumbnail group  203 . Each thumbnail group  203  can include one or more thumbnails  205 . Thumbnails  205  related to the same thumbnail group  203  are displayed as a continuous sequence. Thumbnail groups  203  corresponding to separate video clips are displayed such that the last thumbnail  205  of a thumbnail group  203  is separated from the first thumbnail  205  of the subsequent thumbnail group  203 . The order of display of the thumbnails in the thumbnail group corresponds to the order in which the corresponding video clip was captured. Progression of time corresponds to positioning of the thumbnails going from left to right in the horizontal direction and top to bottom in the vertical direction. A video clip  200  can be included to or removed from display in the user interface  100  based on user input. When a thumbnail group  203  corresponding to a video clip  200  is hidden, then the remaining thumbnail groups  203  are re-arranged to fill the gaps corresponding to the hidden thumbnail group  203 . In this manner, the thumbnail groups  203  are displayed in a manner analogous to words in a word processing application user interface. 
     Each thumbnail  205  is assigned a portion of the time period of video content in the video clip  200 . The duration of a video clip  200  is divided by the time period assigned to each thumbnail  205 . In this manner, the number of thumbnails  205  in a thumbnail group  203  required to display the video clip  200  is determined. The duration of a video clip  200  may be exactly divisible by the time period assigned to each thumbnail  205  with no remaining time. In such cases, when the duration of the video clip  200  is divided by the time assigned to each thumbnail  205 , the number of thumbnails  205  in a thumbnail group  203  required to display the video clip  200  equals the quotient of division (Q) with no time remaining. The video clip  200  is displayed across Q thumbnails  205  in the thumbnail group  203 . Alternatively, there may be time remaining after dividing the total time period of the video clip  200  by the time period assigned to each thumbnail  205 . In such cases, the number of thumbnails  205  in the thumbnail group  203  required to display the video clip  200  equals the quotient of the division (Q) plus one. The video clip  200  is displayed across (Q+1) thumbnails  205  in the thumbnail group  203 . Also, in such cases, the time period corresponding to the last thumbnail  205  in the thumbnail group  203  is less than that corresponding to the other thumbnails  205  in the thumbnail group  203 . Nevertheless, the dimensions of all the thumbnails  205  in the thumbnail group  203  related to a video clip  400  are equal to one another. The segment of the last thumbnail  205  of the video clip  200  containing no video content is filled with a color, for example, grey, when the cursor on the display device is placed on the thumbnail. In this manner, a user can readily discern that the filled segment of the last thumbnail  205  of a thumbnail group  203  is void of any video content. The segment of the thumbnail  205  void of content is not used during editing. The aesthetics of the user interface  100  are improved by keeping equal the dimensions of all the thumbnails  205  in the thumbnail group  203  and avoiding the display of fractionated thumbnails  205  to represent content of shorter time periods. 
     In some implementations, where the time period of the content in the last thumbnail is less than the time period of the other thumbnails in the thumbnail group, the content of the last thumbnail in the thumbnail group is distributed across the entire dimension of the thumbnail. In such implementations, despite a mismatch in the time period of content in the last thumbnail and the remaining thumbnails in the same thumbnail group, each point in the physical space occupied by a thumbnail corresponds to a frame in the media item. In other implementations, where the time period of the content in the last thumbnail is less than the time period of the other thumbnails in the thumbnail group, the dimensions of the last thumbnail can be truncated to indicate the reduced time period. 
     A user can alter the time period assigned to the thumbnails  205  in the user interface  100 . The thumbnails  205  in the project pane  110  can be assigned a different time period than the thumbnails  205  in the media pane  105 . In some implementations, a first interactive scale and a second interactive scale are displayed adjacent to the media pane  105  and the project pane  110 , respectively. The scales are operatively coupled to the respective panes such that the time assigned to thumbnails in the media pane  105  and that assigned to the thumbnails in the project pane  110  can be independently altered by sliding the first scale and the second scale, respectively. In some implementations, the time period corresponding to each thumbnail  205  is assigned by the system. In other implementations, the time period corresponding to each thumbnail  205  is specified by the user. In other implementations, when a video clip  200  is first loaded into the media pane  105 , each thumbnail  205  is assigned a time period that is equal to a system default value. A user can alter this value to a user-defined value within limits specified by the system. 
     The vertical and horizontal dimensions of the thumbnails  205  are uniform and are designated by the system. The dimensions of the media pane  105  and the project pane  110  may be insufficient to display all the thumbnails  405  related to one or more thumbnail groups  203  in the same row. In some implementations, an interactive scale is displayed adjacent to the media pane  105  and the project pane  110 . The scale is operatively coupled to the dimensions of the thumbnails in the media pane  105  and the project pane  110 . A user can change the position of the scale to increase or decrease the size of the thumbnails  205  in the media pane  105  and the project pane  110 . In this manner, the size of the thumbnails  205  displayed in the media pane  105  and the project pane  110  can be simultaneously altered. In other implementations, the size of the media pane  105  is automatically increased to accommodate all thumbnails  205  by adding rows. Nevertheless, the dimensions of the media pane  105  displayed remain unaltered. A vertical scroll bar is incorporated into the media pane  105  so that the user may scroll vertically to access video clips  200  that are not immediately viewed. In other implementations, the user can pan the media pane  105  using the pointing device or the keyboard or both. The size of display of the thumbnails  205  can also be altered by a combination of resizing thumbnails using an interactive scale and increasing the size of the media pane  105 . 
       FIG. 3  depicts an example of a schematic of a user interface  100  displaying a plurality of video clips  200  as corresponding thumbnail groups  203 . Each thumbnail group  203  includes one or more thumbnails  205 . In some implementations, all video clips  200  of a video library can be automatically uploaded into the user interface  100  and displayed in the media pane  105  as rows of thumbnail groups  203 . In other implementations, one or more video clips  200  of a video library can be selectively uploaded into the user interface  100 , based on user input, and displayed in the media pane  105 . The default dimensions of the user interface  100  are designated by the system. Based on the time period assigned to a thumbnail  205  and based on the duration of a video clip  200 , each video clip  200  is distributed across one or more thumbnails  205  in a thumbnail group  203 . In the example shown, in the default view of the user interface  100 , the thumbnail groups 1, 2, 3, and 4 correspond to video clips 1, 2, 3, and 4 which are displayed across 6, 1, 3, and 1 thumbnails, respectively. If the total width of the thumbnails  205  in a row exceeds that of the media pane  105 , a new row is added, and subsequent thumbnails  205  are wrapped within the media pane  105  and displayed in the following row. The size of the thumbnails in the media pane  105  and the project pane  110  can be altered proportionally based on user input. 
     The number of thumbnails  205  in a thumbnail group  203  to display the video clips  200  is automatically altered based on the time period assigned to each thumbnail  205 . When a video clip  200  is displayed across one or more thumbnails  205  in a thumbnail group  203 , the time periods corresponding to each thumbnails  205  are equal to one another, except for the last thumbnail  205  in each thumbnail group  203 . The time period corresponding to the last thumbnail  205  in a thumbnail group  203  is either less than or equal to, but not greater than, the time period corresponding to other thumbnails  205  in the same thumbnail group  203 . Each video clip  200  can be displayed as a single thumbnail  205  in response to user input. In such implementations, the dimensions of the thumbnails  205  corresponding to the video clips  200  are equal to one another. The duration of the video clips  200  represented by a thumbnail  205  need not be equal to one another. 
     When a cursor on the display device is placed over a thumbnail  205  in the user interface  100 , a playhead is displayed on the display device at the position of the cursor. In some implementations, the playhead is a vertical line of height equal to the vertical dimension of the thumbnail  205 . When the cursor is placed at a position away from a thumbnail  205 , the playhead disappears. A user may alter the position of the cursor on the display device by operating the pointing device or the key board or both. When the playhead is positioned at a position on a thumbnail  205 , a frame in the video corresponding to a time instant determined by the position of the playhead on the thumbnail is displayed in the preview pane  115 . In this manner, frames related to video content displayed across one or more thumbnails in the media pane  105  and the project pane  110  can be previewed in the preview pane  115 . 
     When the playhead is positioned on a thumbnail  205 , a frame in the video clip  200  corresponding to the position of the playhead is displayed on the thumbnail  205 . As the playhead is moved across the thumbnail  205 , the display on the thumbnail  205  is continuously updated with the frame corresponding to the new position of the playhead. Further, the frame that is displayed on the thumbnail  205  is simultaneously displayed on the preview pane  115 . As the frames displayed on the thumbnail  205  are updated as the playhead is moved, the frames displayed in the preview pane  115  are also updated. 
       FIGS. 4A-4E  depict examples of schematics of frames in a video clip corresponding to positions of a playhead. In the examples shown, the playhead is moved horizontally across thumbnail number 2 in thumbnail group number 3. As the playhead is moved from the left of the thumbnail (playhead position 1) to the right of the thumbnail (playhead position 5), frames corresponding to the positions of the playhead are displayed in the preview pane  115 . The rate at which frames are updated in the preview pane  115  corresponds to a play speed. The play speed input is provided by the user. In some implementations, a user, using a mouse as a pointing device, can move the mouse horizontally across the one or more thumbnails  205 . The play speed corresponds to the speed with which the user moves the pointing device. In other implementations, the system can have one or more designated play speeds which the user can choose. Scrubbing refers to previewing the contents of one or more thumbnails  205  by moving the cursor over the thumbnail  205  in the thumbnail group  203  in forward or reverse directions. The contents of a thumbnail  205  can be scrubbed by a simple mouse over operation that does not require clicking the mouse on the thumbnail  205  to preview a frame in the preview pane  115 . The time line representing progression a of video clip runs from left to right. Therefore, moving the playhead from left to right displays the frames corresponding to the position of the playhead in the preview pane  115  in the sequence in which the frames were recorded. Similarly, moving the playhead from right to left displays the frames corresponding to the position of the playhead in the preview pane  115  in the sequence opposite to that in which the frames were recorded. A user may move the playhead at a play speed placed over a thumbnail  205  using the pointing device either from the left to the right or the right to the left or both to scrub the contents of the thumbnail  205  in the preview pane  115 . When the user ceases to move the mouse, play speed input is stopped, and scrubbing is ceased. 
     As the playhead is moved across one or more thumbnails  205  at a play speed, the preview pane  115  is continuously updated with frames corresponding to the position of the playhead on the thumbnails  205 . In this manner, the contents of the video clip  200  are scrubbed. The recording instrument may have a feature to record both video and audio content. Thus, the video clip can include audio content recorded along with the video content. When the contents of the video clip are scrubbed, both the video and the audio content can be played back in forward or reverse depending on the direction of movement of the playhead. In some implementations, if the play speed is less than a first threshold, both the video and audio content of the segment being scrubbed are played back. Depending on the audio features of a system, both video and the audio associated with the video are scrubbed either in forward or reverse direction depending on user input. The sequence in which the video and audio content is played back corresponds to the direction of movement of the playhead. If the play speed exceeds the first threshold, but is below a second threshold, only the video content and not the audio content, if any, is scrubbed. If the play speed exceeds the second threshold, then neither the video nor the audio associated with the video are played back. In such cases, the default view of a thumbnail  205  is displayed in the preview pane  115 . The default view of a thumbnail can include any frame of the video clip including a frame in the thumbnail on which the playhead is located and a frame in any thumbnail of the video clip to which the thumbnail is related, regardless of the position of the playhead. Default view of a thumbnail is also displayed in the preview pane  115  if the direction of motion of the playhead is determined to be substantially vertical. The video content displayed in the media pane  105  can be played back and previewed in the preview pane  115  at a play speed. The user can start and stop play back at any desired position in any thumbnail displayed in the media pane  105 . 
     From the video clips  200  uploaded in the media pane  305 , a user can select segments of video and transfer the selected segments to the project pane  110 .  FIG. 5  depicts an example of a schematic of segments of video content selected from the media pane  105  and transferred to the project pane  110 . In this manner, the user may edit the content of the raw footage displayed in the media pane  105 . Content from thumbnails  205  in the media pane  105  are selected in a manner analogous to selecting text in a text editor. The playhead is placed at a desired starting position on a thumbnail  205 . The user may choose the starting position on a thumbnail  205  based on the preview of a frame in the preview pane  115  obtained by placing the playhead at a position in the thumbnail  205 . In some implementations, the pointing device is a mouse. The user can select the starting position on the thumbnail  205  by placing the playhead at the desired position and clicking the mouse. Subsequently, the user can move the mouse horizontally across all or segments of the thumbnail group  203  corresponding to a video clip  200  to a desired ending position. When the user clicks the mouse at the desired ending position, the segment spanned by the playhead is selected. In some implementations, the spanned segment may be displayed as a shaded rectangle that can be readily discerned. The ending position of a selected segment can be located before or after the starting position of the selected segment. The starting position and the ending position of the selected segment lie within the same thumbnail group and are related to the same video clip. 
     In other implementations, the user can select segments of a video clip  200  by a click and drag operation using a pointing device, for example, a mouse. In other implementations, the user can select segments of a video clip  200  by selecting the starting position and the ending position without dragging the playhead from the starting position to the ending position. For example, the user may place the playhead on the desired starting position and click the pointing device such as a mouse. The user may hold down the “Command” key on the key board, move the playhead to the desired ending position, and click the mouse at the ending position. The segments between the starting and ending position are automatically selected. Any combination of one or more keys on the key board or the pointing device or both can be designated to perform the segment selection operation. 
     In some implementations, the user can select segments of video from one or more thumbnails displayed on different rows in the media pane  105 . The user can select a starting position and an ending position using a combination of one or more keys on the key board or the pointing device or both such that the starting position is located on a row different from the ending position. All the content between the starting position and the ending position, regardless of the rows on which the starting and ending position are located, can be selected. In some implementations, the user can select a plurality of segments from among the video clips  200  displayed in the media pane  105 . Each segment can have a starting position and an ending position. For example, the user can select a first segment of a video clip  200  by clicking the mouse at a starting position and dragging the mouse to an ending position. Alternatively, the user can select a first segment by clicking the mouse at the starting position, holding down a key on the key board, for example, the “Command” key, and clicking the mouse at the ending position. Subsequently, the user can hold down a second key on the key board, for example, the “Shift” key, and repeat the process for selecting a segment at a different position in the media pane  105 . In this manner, the user can select multiple segments of the video clip  200  from the media pane  105 , wherein each selected segment has a starting position and ending position. 
     One or more selected segments of the one or more video clips  200  can be transferred from the media pane  105  to the project pane  110 . In some implementations, a segment of video selected in the media pane  105  can be transferred to the project pane  110  without clicking the pointing device, for example, a mouse, on the selected segment. Placing the pointing device at any point in the selected segment allows moving the entire selected segment to the project pane  110  without clicking the pointing device at any point in the selected segment. In other implementations, the selected segments can be dragged from the media pane  105  and dropped into the project pane  110  in a manner similar to text editing. In other implementations, the selected segments can be cut from the media pane  105  and pasted into the project pane  110  in a manner similar to text editing. In such implementations, when the selected segments are transferred from the media pane  105  to the project pane  110 , the selected segments may be removed from display in the media pane  105 . In other implementations, the selected segments can be copied and the copied segments can be pasted into the project pane  110 . In such implementations, the selected segments continue to be displayed in the media pane  105  as well as the project pane  110 . 
     Each selected segment can be transferred individually from the media pane  105  to the project pane  110 . Alternatively, one or more selected segments can be transferred simultaneously to the project pane  110 . The transferred segments are displayed as a corresponding thumbnail group. A thumbnail group corresponding to a transferred segment includes one or more horizontal rows of thumbnails, wherein the height of each thumbnail is equal to one another. The number of thumbnails across which a transferred segment is displayed depends on a time assigned to each thumbnail and can be altered by a user. Segments transferred first appear as thumbnails on the left end of a row in the project pane  110 . Segments transferred subsequently are displayed as one or more thumbnails to the right of the one or more thumbnails related to segments already present in the project pane  110 . The segments are separated by a system designated space to distinguish between segments. A segment can be inserted at any position in a row including the start of the row, the end of the row, or any position in between. All transferred segments are separated by a system designated distance. If the width of the thumbnails exceeds the width of the project pane  110 , a new row is added to the project pane and subsequent segments are transferred to the new row. The size of the thumbnails in the project pane  110  can be altered along with the size of the thumbnails in the media pane  105  by varying the position of an interactive scale that is configured to alter the vertical and horizontal dimensions of the thumbnails. 
     The selected segments of the video clip displayed in the project pane  110  can be re-arranged based on user input. In some implementations, a user can change the position of a selected segment by placing the pointing device, for example, a mouse, anywhere on the selected segment, moving the selected segment from its present position, and placing the selected segment at a desired position. The entire selected segment can be moved regardless of the point in the selected segment where the mouse is located. A first selected segment can be dragged and dropped to positions including the start of a second segment, the end of a second segment, the start of a row, and the end of a row. The contents of the segments selected by the user, transferred to the preview pane  110 , and displayed in a sequence desired by the user can be scrubbed by moving the playhead. In a manner similar to scrubbing the contents of thumbnails in the media pane  105 , the contents in the preview pane  110 , including audio, can be previewed in the preview pane  110  based on the speed of movement of the playhead. In addition, the contents of the transferred segments can be played back as a continuous video clip. The contents of the segments in the project pane  110  can be played back and previewed in the preview pane  115 . The user can start and stop play back at any desired position in any thumbnail displayed in the project pane  110 . 
     The video content displayed in the media pane  105  and the project pane  110  is aligned relative to a time line. In some implementations, a user can add and associate overlay content, including audio tracks, voice-overs, titles, and transitions between frames in the video, to the video content displayed in the project pane  110 . The user can add overlay content at any position in the project pane  110  and anchor a point in the overlay content to a point in the video content displayed in the project pane  110  such that the point in the additional content is played back at the same instant as the anchored point in the video content, regardless of the time in the time line when the point in the video content is played back. In this manner, the play back of a first point in the overlay content can be synchronized to a second point in the video content. In some implementations, when the user includes overlay content into the content displayed in the project pane  110 , the overlay content is displayed as a horizontal bar beneath the thumbnail group  203  corresponding to the video content to which the overlay content is associated. Any point in the overlay content can be synchronized to any point in the video content in the project pane  110 . The display of a horizontal bar beneath a thumbnail  205  is an indication of overlay content. 
     The overlay content, for example, an audio track, is anchored to a specific point in the video content.  FIG. 6  depicts an example of overlay content anchored to video content in a project pane  105 . The user may anchor the overlay content to a specific position in the video content so that the anchored point in the overlay content plays back whenever the corresponding anchored point in the video content plays back, regardless of the time instant when the rest of the video content and the overlay content plays back. In some implementations, the user can choose a first point in the video content and then choose the overlay content. The starting point in the overlay content is automatically anchored to the first point. In other implementations, when the user adds overlay content to a thumbnail related to video content in the project pane  110 , the overlay content is automatically anchored to the first frame in the first thumbnail in the thumbnail group. Subsequently, the user can relocate the anchored point in the overlay content and the anchored point in the video content to any desired point using the pointing device. The user can relocate the anchored point in the video content based on a preview of a frame related to a thumbnail displayed in the project pane  110  viewed in the preview pane  115 . In some implementations, the anchored points in the video and audio content are displayed as points connected by a vertical line. In such implementations, regardless of additions to, deletions from, or re-arrangements of the video content in the project pane  110 , the position of the anchored point in the overlay content relative to the anchored point in the video content remains unaltered. The overlay content before and after the anchored point is automatically adjusted such that the point in the overlay content plays back at the same time instant as the point in the video content to which it is anchored. 
     In some implementations, the overlay content is a voice-over that a user can add to the video content. The user can select a point in the video content displayed in the project pane  310  as the starting point of the voice over. The user can record audio for a desired time period. The user can select an ending point for the end of the voice over. The starting point of the voice over is anchored to the chosen starting point in the video content. The user can independently move the anchored point in the video content and the anchored point in the voice-over to any desired point second point in the thumbnail group representing the video content and the horizontal bar representing the voice over, respectively. 
     In some implementations, the overlay content can include transitions between frames. The system can include a plurality of transition styles. In some implementations, the user can choose and insert a transition style between two frames. The transition can appear as a rectangular thumbnail with vertical dimension equal to the vertical dimension of the thumbnails representing the selected segments. The horizontal dimension of the thumbnail representing a transition can be varied based on user input. The user can alter the duration of the transition by altering the horizontal dimension of the thumbnail representing the transition. In this manner, the user can edit the raw footage recorded using the recording instrument and add features to the edited video clip. Subsequently, the user can store the edited video clip on a storage device. The storage device may be the storage device on which the raw footage is stored. Alternatively, the storage device may be a separate device. 
       FIG. 7  depicts an example of a flow chart of a method of displaying video clips  200  as a series of one or more thumbnails  205  in a thumbnail group  203 . In some implementations, the video clips  400  are uploaded into the media pane  305  at  700 . The system  100  assigns a default time period for each thumbnail  205 . This system value for each thumbnail  205  is obtained at  705 . The video clip  200  is displayed as a thumbnail group  203  based on the duration of the video clip  200  and the system value for time period of a thumbnail  205  at  710 . The thumbnail group  203  can include one or more thumbnails  205 . A user can alter the time period assigned to each thumbnail  205 . If the time period for each thumbnail  205  is altered by a user ( 715 ), the user specified time is used to determine the number of thumbnails  205  in the thumbnail group  203 . If not, then the system assigned value is used to determine the number of thumbnails  205  in the thumbnail group  203 . If the user specifies an input to display each video clip  200  as a single thumbnail  205  ( 720 ), each video clip  200  is displayed as a single thumbnail  205  at  725 . If the user does not specify a time period for a thumbnail  205 , then the duration of the video clip  200  is divided by the system assigned value for time period of a thumbnail  205  and a quotient of the division (Q) is determined at  730 . If the user specifies a time period for a thumbnail  205 , then the duration of the video clip  200  is divided by the user specified value and a quotient of the division (Q) is determined at  735 . If no time remains post division ( 740 ), the video clip is displayed across Q thumbnails at  745 . The thumbnail group  203  includes Q thumbnails  205 . If time remains post division ( 740 ), the video clip is displayed across (Q+1) thumbnails at  750 . The thumbnail group  203  includes (Q+1) thumbnails  205 . 
     The display of segments of video content transferred from the media pane  105  to the project pane  110  and the number of thumbnails  205  in the thumbnail group  203  representing the segment can also be altered based on the duration of a segment and a time period assigned to each thumbnail in the project pane  110 . A user can transfer segments of video of any time period from the media pane  105  to the project pane  110 . The time period assigned to each thumbnail in the project pane  110  is assigned a default system value which can be altered based on user input. The number of thumbnails required to display a transferred segment as a thumbnail group is a function of the duration of the segment and the time period assigned to each thumbnail. The time period assigned to a thumbnail in the media pane  105  can be altered independently from the time period assigned to a thumbnail in the project pane  110 . 
       FIG. 8  depicts an example of a flow chart of a method of previewing a frame corresponding to a time instant in a video clip  200 . The video clip  200  may be displayed as one thumbnail  205  or a horizontal sequence of a plurality of thumbnails  205  in a thumbnail group  203 . A cursor on the display device can be controlled by the key board or the pointing device or both. The cursor is placed on a thumbnail  205  related to a video clip  200  at  800 , wherein the cursor is displayed as a playhead. The time instant in the video clip  200  corresponding to the position of the playhead on the thumbnail  205  is determined at  805 . A frame in the video clip  200  corresponding to determined the time instant is identified at  810 . The identified frame is displayed in the preview pane  115  at  815 . 
       FIG. 9  depicts an example of a flow chart of a method of scrubbing based on a play speed of a playhead. The playhead can be controlled using the key board or the pointing device or both. By moving the playhead across one or more thumbnails, the frames corresponding to the positions of the playhead are displayed in the preview pane  115 , and can, thus, be scrubbed. The play speed with which the playhead is moved across a thumbnail  205  is determined at  900 . If the direction of motion of the playhead is substantially vertical, then the frames in the thumbnail  205  are not scrubbed. A default view of the thumbnail  205  is displayed in the preview pane  115  at  910 . If the play speed is determined to not be substantially vertical, the play speed is compared with a first threshold at  915 . If the play speed is less than the first threshold, both video and audio content corresponding to the position of the playhead are scrubbed ( 920 ). If the play speed is greater than the first threshold, then the play speed is compared with a second threshold at  925 . If the play speed is greater than the first threshold and lesser than a second threshold, then only the video content of the frame is scrubbed at  930 . The audio content associated with the frame is not scrubbed. If the play speed is greater than the second threshold, then the play speed is deemed too fast to update frames in the preview pane and the default view is displayed. Neither the video nor any other associated content is scrubbed. The default view can be any frame including the starting frame of the thumbnail  205 , the ending frame of the thumbnail  205 , the starting frame of the thumbnail group  203  representing the video clip  200 , and the ending frame of the thumbnail group  203  representing the video clip  200 . 
       FIG. 10  depicts an example of a flow chart of a method of synchronizing overlay content to video content. The overlay content is overlaid on the video content displayed in the project pane  110 . Based on user input, the content to be overlaid is added to the project pane  110  at  1000 . The overlay content includes one or more of audio tracks, voice-overs, titles, transitions between video, and combinations of the three. In some implementations, the overlay content is displayed in the project pane  110  as a horizontal bar in the gutter between rows of thumbnail groups  203  representing video content. The user can synchronize a first point in the overlay content to play back whenever a second point in the video content is played back. In some implementations, the user picks a first point on a thumbnail  205 . The user then adds the overlay content. The starting point of the overlay content is automatically anchored to the first point in the thumbnail. In other implementations, the user adds the overlay content to a thumbnail in the project pane  110 . The starting point of the overlay content is automatically anchored to the starting point of the thumbnail to which the overlay content is added. The anchor is displayed as two points, each located on the video content and the overlay content, connected by a vertical line. Based on user input, the first anchor point is moved to a first synchronization point at  1005 . Similarly, based on user input, the second anchor point in the overlay content is moved to a second synchronization point at  1010 . The first synchronization point is anchored to the second synchronization point at  1015 . Once anchored, the second synchronization point in the overlay content always plays back at the same time as the first synchronization point in the video content to which it is anchored, regardless of additions to or deletions from the video content and the overlay content. The anchor points on the video content and the overlay content can be moved using the pointing device or the key board or both. 
       FIG. 11  depicts an example of a schematic of a system in which the video editing software is implemented. The system  1100  includes a display device  1105 , a central processing unit (CPU)  1110 , a key board  1115 , and a pointing device  1120 . The software can be implemented in virtually any suitable system  1100  (e.g., desktop computer, laptop computer, personal digital assistant (PDA), smartphone, work station). Information can be displayed to a user using any suitable display device  1105  including a cathode ray tube (CRT) and liquid crystal display (LCD) monitor. A user can use a key board  1115  and virtually any suitable pointing device  1120  (e.g., mouse, track ball, stylus, touch screen) to interact with the video editing software. The display device  1105 , the key board  1115 , and the pointing device  1120  can be operatively coupled with the CPU  1110  through wired or wireless means. 
     In some implementations, the software can be installed on a CPU  1110  controlled by an operating system such as Macintosh Operating System (Mac OS) X v10.0. In other implementations, the software can be installed on a CPU  1110  controlled by other operating systems including Microsoft Windows, UNIX, and Linux. In some implementations, the system  1100  is a stand alone device such as a desktop computer. In other implementations, the system  1100  is a network where the software is installed in a centralized server and a user can access the software through one or more nodes such as work stations. 
       FIG. 12  depicts an example of a schematic of a central processing unit  1110 . The CPU  1110  includes a microprocessor  1200 , a random access memory (RAM)  1205 , and a read only memory (ROM)  1210 . When a user runs the video editing software application installed on a system  1100 , the user provides instructions to the CPU  1110  using one or more of the input devices including the keyboard  1115  and the pointing device  1120 . The microprocessor  1200  performs the operations specified by the user based on user input and instructions from RAM  1205  or ROM  1210  or both. The system  1100  displays the output on the display device  1105 . In addition, the CPU  1110  can include a storage device to store content including raw footage recorded using the recording instrument, edited video, and additional content. In some implementations, the storage device resides in the CPU  1110 . In other implementations, the storage devices resides external to the CPU  1110 . In other implementations, the storage device resides in the recording instrument. The recording instrument is operatively coupled to the CPU  1110  through wired or wireless means to retrieve stored content. 
     Although a few implementations have been described here, other modifications are possible. For example, the video editing software can be embedded into the recording instrument. The display device on which the recorded content is played back can be used to display the user interface  100  including the media pane  105 , the project pane  110 , and the preview pane  115 . A user can use a pointing device  1120  including a stylus and a touch screen to scrub across thumbnails in the media pane  105 , select segments of video from the thumbnails in the media pane and  105  and transfer the selected segments to the project pane  110 . Preview of the content in the thumbnail groups  203  displayed in the media pane  105  or the segments of video content in the project pane  110  or both can be viewed in the preview pane  115 . Additional content to be laid over the video content in the project pane  110  can be stored in a storage device located in the recording instrument. Alternatively, the content to be overlaid can be stored in a separate storage device that can be operatively coupled to the recording instrument. 
     In some implementations, more than one user interface  100  can be opened and viewed simultaneously. For example, video clips  200  in a first video library can be uploaded into a first media pane  105  in a first user interface  100 . Video clips in a second video library can be uploaded into a second media pane  105  in a second user interface  100 . The video clips from the first media pane  105  can be selected and transferred to the second media pane  105 , and vice versa, by operations similar to text editing including drag and drop, cut and paste, and copy and paste. The time period of the one or more thumbnails  205  related to a video clip  200  in the first media pane  105  need not be the same as the time period of the one or more thumbnails related to a video clip  200  in the second media pane  105 . When a video clip  200  is transferred from the first media pane  105  to the second media pane  105 , the one or more thumbnails  205  related to the transferred video clip  200  can be automatically assigned the time period of the one or more thumbnails  205  in the second media pane  105 , and vice versa. Segments of video selected in the first media pane  105  in the first user interface  100  can be selected and transferred to the second project pane  110  in the second user interface  100  by operations similar to text editing including drag and drop, cut and paste, and copy and paste, and vice versa. Video segments can be selected and transferred from the first project pane  105  to the second project pane  105 , and vice versa. The video content in the media pane  105  and project pane  110  in the user interface  100  can be previewed in the preview pane  115  in the corresponding user interface  100 . The user interfaces  100  can be displayed as a cascade on the display device  1105 , wherein each user interface  100  can be independently accessed, viewed, and re-sized, based on user input. 
     In another implementation, more than one media pane  105  can be opened and viewed in the same user interface  100 . For example, video clips in a first video library can be uploaded into a first media pane  105  in a user interface  100 . A second media pane  105  can be opened in the same user interface  100  and video clips in a second video library can be uploaded into the second media pane  105 . Video clips  200  can be selected from the first media pane  105  and transferred to the second media pane  105 , and vice versa, by operations similar to text editing including drag and drop, cut and paste, and copy and paste. The time period assigned to the one or more thumbnails  105  related to a video clip  200  transferred from a first media pane  105  to a second media pane  105  in the same user interface  100  can be automatically adjusted to correspond to the time period assigned to the thumbnails  205  in the second media pane  105 . The video content in the first media pane  105  and the second media pane  105  can be previewed in the same preview pane  115  in the user interface  100 . Segments of video content from the first media pane  105  and the second media pane  105  can be selected and transferred to the same project pane  110  by operations similar to text editing including drag and drop, cut and paste, and copy and paste. 
     In another implementation, more than one project pane  110  can be opened and viewed in the same interface  100 . Segments of video from the same media pane  105  or different media panes  105  can be selected and transferred to a first project pane  110  and a second project pane  110 . Segments of video can also be transferred between two project panes  110 . The content of each project pane  105  can be saved as a separate finished project. In this manner, a user can work on one or more projects simultaneously. 
     In some implementations, the panes of a user interface  100  can be displayed on the display device  1105  as disconnected from each other. The media pane  105 , the project pane  110 , and the preview pane  115  can be displayed as separated from each other on the display device  1105 . Each pane can be independently accessed, moved, and resized, based on user input. Although the panes are displayed as disconnected, selecting segments from the media pane  105 , transferring segments to the project pane  110 , and preview of video in the media pane  105  or the project pane  110  in the preview pane  115  can remain unaffected. Based on user input, two or more panes can be reconnected. 
     In some implementations, the media pane  105  can occupy the right half of the user interface and the project pane  110  and the preview pane  115  can occupy the left half, or vice versa. The one or more video clips  100  can be displayed in the media pane  105  as columns of thumbnail groups  203 . The playhead can be displayed as a horizontal bar that appears when the cursor on the display device  1105  is placed over a thumbnail. Frames in the thumbnail groups  203  can be previewed by scrubbing the playhead vertically over one or more thumbnails  205 . 
     In some implementations, when one or more video clips  200  are uploaded into a media pane  105  and displayed as one or more thumbnails  205 , the title under which each video clip  200  is stored in the storage device can appear adjacent to the video clip  200 . Further, depending on the number of thumbnails  205  across which each video clip  200  is distributed, thumbnail numbers may appear adjacent to each thumbnail  205 . In other implementations, additional data representative of the one or more video clips  200  may appear in the media pane  105 . 
     In some implementations, when a segment of video content displayed in one or more thumbnails  205  in the media pane  105  is selected, the selected segment can be removed from display in the media pane  105 . Alternatively, all segments of a thumbnail except the selected segment can be removed from display in the media pane  105 . A user can provide input to permanently delete the removed segments from the raw footage. Similarly, segments displayed in the project pane  110  can also be removed from display. 
     In addition, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Accordingly, other implementations are within the scope of the following claims.