Have you ever thought about to concert your ASF video to FLV? Because you can upload the FLV file to YouTube with no difficult, and you can reduce your ASF video’s size but will not loss the quality. But how to convert ASF to FLV? I suggest you to use Flash Video MX Pro.
This software is not just powerful but also easy to operate; just follow these simple steps to enjoy perfect experience.

1). Install and launch Flash Video MX Pro
This is the main interface; input ASF to convert by clicking open button (in red):

2). Editing
A). Crop the video size as well as adjust the video effect by "Edit" and "Effect" functions:

B). "CuePoint" also is a very powerful feature:
A "navigation" cue point allows you to seek to a particular frame in the FLV file because it creates a key frame within the FLV file as near as possible to the time that you specify.
An "event" cue point enables you to synchronize a point in time within the FLV file with an external event on the web page.
C). Generate a picture as the first frame of the output file by the snapshot function if needed.
D). Add watermark on your video.
Choose Watermark section, press add button, and you can choose add an image or a text watermark.
E). Set the volume of the video.
In this section, you set some effects on your video, like set the Brightness and Contrast. And you also can increase or reduce the audio’s volume.

3). Replace audio
Click "Next" to this interface, in "Misc" section, you can replace the original audio with others you like. As you see, in Replace audio section click this button: to find the song you want to add.

This software gives you 3 choices to choose: "Generate Flash video (FLV)", "Embed the video in SWF and play in timeline", and "Generate HTML file". Or if you just want a FLV file, you can disable Generate Flash (SWF) and Generate HTML file. And if you want to upload your video on your website you had better to generate the SWF file and the HTML file which can be used as a webpage directly.

4). Add player skins
Here are various player skins, preloaders and special effects right for you to decorate your video into the best one in your mind.

5). Convert
Click "Start" and wait a few minutes you will get your .flv file.