Selecting compression profiles in the Video Import wizard

The Video Import wizard provides a range of options for compressing a video clip during the import process. In the Encoding panel, you can enter a value for Bandwidth or Quality, control the frequency of keyframes, ensure consistent image quality in keyframes, increase encoding speed, and match the playback speed of the imported video to the playback speed of the main Flash document Timeline.

You select a compression profile to choose the level of compression that will be applied to the imported embedded video. You can select a profile based on bandwidth or video quality.

You can synchronize the frame rate of an embedded video to match the frame rate of the main Timeline. You can also adjust the ratio of the video frame rate to the main Timeline frame rate, to drop frames from the imported video during playback.

In some situations, you may not want to synchronize the embedded video with the SFW file. Instead, you want to prevent frames in the embedded video from being dropped or duplicated. For example, suppose you want to import an NTSC video clip with a frame rate of 29.97 frames per second (fps) into a Flash document with a frame rate of 30 fps. Deselecting the Synchronize option keeps frames from being dropped in the embedded video and prevents the hiccup effect that this causes during playback.

You can save customized compression profiles as named settings. The new settings appear in the Compression Profile pop-up menu.

To create a custom compression profile:

From the Compression Profile pop-up menu in the Encoding panel, select Create New Profile or a predefined compression rate and then click Edit.
Do one of the following:
- Select Bandwidth and drag the slider or enter a Bandwidth value between 0 and 750 Kbps. Bandwidth options specify the approximate download speed, in kilobits per second, for the video. The quality setting of individual frames may vary, in order to achieve a consistent download speed.
- Select Quality and drag the slider or enter a quality value between 0 and 100. Quality options specify a compression level for all frames. Higher values yield better images but increase download time. The download speed may vary in order to achieve a consistent compression level.
Drag the slider or enter a value for Keyframe Interval to control the frequency of keyframes (frames with complete data) in the video clip. For example, with a keyframe interval of 30, Flash stores a complete frame every 30 frames. For frames between intervals, Flash stores only the data that changes from the preceding frame. With smaller intervals, you can fast-forward or rewind more quickly to a specific frame, but file size is larger.
Note: A keyframe interval of 1 stores a complete frame for each frame of the video. This setting is recommended only for very small video files.
If you are encoding the video using a bandwidth value, select High Quality Keyframes to ensure consistent image quality in keyframes. Using a consistent bandwidth speed can reduce the quality of keyframes if you do not select this option.
Select Quick Compress to reduce the time it takes to compress a file. Increasing encoding speed may also decrease image quality.
Select Synchronize Video to Macromedia Flash Document Frame Rate to match the playback speed of the imported video to the playback speed of the main Flash document Timeline. Deselect this option to prevent frame rate synchronization.
Select a value for Number of Video Frames to Encode Per Number of Flash Frames to specify the ratio of imported video frames to main Flash Timeline frames. For example, to play one imported video frame for every main Flash Timeline frame, select 1:1; to play one imported video frame for every two main Timeline frames, select 1:2.
Dropping frames from the imported video does not slow down the motion of the video. Instead, it displays fewer frames per second, so that the video appears more choppy in playback.
Click Next.
Enter a name and description on the Encoding (Part 3, Save) panel. Click Next to save the setting.
Do one of the following:
- Edit the Advanced settings.
- Click Finish.
If you chose Current Timeline or Graphic Symbol for Track Options, a notification appears if the imported clip contains more frames than the current Timeline. Do one of the following:
- Click Yes to add the required number of frames to the current Timeline span.
- Click No to keep the span at its current size. Frames in the imported clip that exceed the frames in the span are not displayed unless you subsequently add frames to the span.