Flash MX Video Support (written in 2002)    

Flash MX has been a wildly successful vector streaming application from Macromedia. Flash MX (also known as Flash 6) adds video related features that had been "missing" from the product for quite some time. While the addition of video support is quite welcomed, Flash MX does not appear without some rather annoying bugs that are described below.

By default, Flash MX utilizes the standard version of the Sorenson Spark codec to import video. Sorenson Spark is an interframe codec with the first frame always being a keyframe.

There are six settings on the import video dialog window:

1. Quality. This setting controls the overall quality of the video being imported. The allowable range is from 0 - 100. A setting of 100 means that the video will be of the highest possible quality whereas a setting of 0 will degrade the quality of the video substantially.

2. Keyframe interval. This setting controls the frequency that keyframes will be inserted in the video file. The allowable range is from 0 - 48. More keyframes will typically result in a higher quality file with faster searching through the clip, but the file will also be (much) larger and consume more bandwidth. A lower number means more keyframes. For example, a setting of 1 means that each frame is treatede as a keyframe. A setting of 30 means that every 30th frame will be a keyframe.

3. Scale. This setting controls the percentage that a video image may be scaled down. The allowable range is from 1 - 100%. Scaling an image down in size reduces file size and bandwidth requirements.


4. Synchronize Video. Check box which indicates whether video should be synchronized with default project frame rate or retain the frame rate as it exists in the file. Deselecting the check means that the original frame rate will be retained.

5. Number of Frames to Encode. This setting is a drop down combo box with the following selections: 1:1, 1:2, 1:3, 1:4, 1:8, 2:3, 3:4. This selection determines whether frames are to be dropped. A setting of 1:1 indicates that no frames are to be dropped. Any other selection determines the approximate percentage (or ratio) of frames to be dropped.

6. Audio Import Dialog. Check box which indicates whether audio should be imported along with the imported video.

Importing Video
Video can be imported as an embedded file or it can be treated as an external file by importing the file into the library. To import a video as an embedded file, select File -> Import (or Control R) to activate the Video Import dialog. Flash MX supports the following file types: avi, .mov, .mpg/mpeg, .wmv, .asf and .dv. (Note that the mpg support appears to be MPEG 2 - not MPEG-1, unfortunately, there is no warning that MPEG-1 files cannot be imported with the Sorenson codec - it will appear to import, but not play back.)

To import a video into a library, select File -> Import to Library.

Publishing a Movie
While Flash MX is capable of importing from various video formats, it is only capable of exporting a movie as a Flash, Quicktime or AVI file.