Add markers
You can add markers to your video in Microsoft Expression Encoder. You generally use markers for two purposes:
As a chapter or a bookmark that you can use to help navigate the footage, much like DVDs use chapters in menus to help users seek to a particular scene in the DVD. This feature is compatible only with Microsoft Silverlight.
As a reference point or a location for some action to occur. After playback reaches a marker, you can specify a method to run a function, such as displaying a Web site or text. You can add script commands to enable this feature of the markers. For more information, see Add script commands.
Once you create markers, you can export them as an XML file. The file contains the time code location of the markers that you set. Conversely, you can import XML files that contain marker information. Expression Encoder reads an XML file and inserts markers in your video that correspond to the time-code location indicated in the XML file. Marker files are specific to the particular video that they refer to, and can function as a cue list.
For example, outside of Expression Encoder, you could view a video, make notes, and create an XML file that includes the time code where you would like to add markers. You can then give this file to another editor, and that editor can import your video into Expression Encoder along with your XML marker file and have the markers that you specified automatically applied to the imported video.
You can add up to 1,000 markers to a video. For each marker, you can specify the following:
Whether you want text associated with the marker Some templates that you use to render the video will display this marker text in the final video.
Whether the marker will force a key frame (or an I-frame) at the marker frame Setting this option shortens the seek time for this marker. WMV files are composed of video data that is contained in I, P, and B frames, but only the I-frames are complete images, whereas the P- and B-frames can only be constructed by using images from other frames. Seeking to a P- or B- frame is possible, but may take more time because the playback program must build a complete frame at the marker point. Selecting this option creates an I-frame at that point, which will likely speed up seek time. However, your video may require re-encoding if you selected Source Profile in the Encode panel because the new keyframes must be encoded.
Whether you want a thumbnail image associated with the marker Some Silverlight packages, or templates, display these thumbnail images as chapter links in your final video.
To create a marker
On the right side of the application window, click the Metadata tab. If the Metadata tab is not visible, then, in the Window menu, click Metadata to open the Metadata panel.
If necessary, click the arrow on the Markers category to expand the options.
On the Timeline, drag the playhead to the point in the video where you want to add a marker.
In the Markers category, click Add. A white marker tab appears on the Timeline.
Do any of the following:
To type any kind of text that you want to be associated with the marker, click Edit, and then type the text in the Value column. If you have created several markers, and you then have to go back to a previous one to modify it, select the marker in the list, and then click Edit.
To force Expression Encoder to create an I-Frame at the marker, select the marker's Keyframe check box. If you want Expression Encoder to create an I-Frame at every marker, select the Keyframe check box at the top of the column.
To extract the marker frame as a thumbnail image, select the Thumbnail check box. If you want each marker to have an associated thumbnail image, select the Thumbnail check box at the top of the column. Note that this image will only be visible if you output your video using a Microsoft Silverlight template. See Encode using Silverlight templates for more information.
To change the location of a marker
Do any of the following:
In the Timeline, drag the marker to a new location. The Viewer pane displays the frame at each new location.
In the Markers category (Metadata panel), select the marker whose location you want to change. In the Timeline, click a location where you want the new marker to be. Then, back in the Markers category, click the Update Time button.
In the Markers category, double-click the Time value of the marker whose location you want to change and type a new time value.
To modify a marker thumbnail
In the Markers category, click the arrow at the bottom of the window to expand the options.
In the Encoding section, choose a compression method from the menu. If applicable, drag the numeric value next to the menu to set a quality level. The higher the number, the higher the quality of compression.
In the Size section, type a size for the thumbnail, or drag the values to set them. Drag the value up or right to increase it, or down or left to decrease it. To maintain the aspect perspective to the height value, select the Maintain Aspect Ratio check box.
To delete a marker
- In the Markers category, select the marker that you want to delete and then click Remove.
To export marker data
Set your markers as described in the procedure "To create a marker," earlier in this topic.
In the Markers category, click Export.
Browse to the location where you want to save the file, and then click Save.
To import marker data
In the Media Content panel, select the video to which you want to add imported marker data.
In the Markers category (Metadata panel), click Import.
Browse to the XML marker file that you want to import, and then click Open.