AVI

AVI is a subformat of the Resource Interchange File Format (RIFF), which divides a file's data into blocks, or "chunks." Each "chunk" is identified by a FourCC tag. An AVI file takes the form of a single "chunk" in a RIFF formatted file, which is then subdivided into two mandatory "chunks" and one optional "chunk". AVI files can contain both audio and video data in a file container that allows synchronous audio-with-video playback. Like the DVD video format, AVI files support multiple streaming audio and video, although these features are seldom used.

- - Wikimedia

WMA

Windows Media Audio (WMA) is the name of a series of audio codecs and their corresponding audio coding formats developed by Microsoft. It is a proprietary technology that forms part of the Windows Media framework. WMA consists of four distinct codecs. The original WMA codec, known simply as WMA, was conceived as a competitor to the popular MP3 and RealAudio codecs. WMA Pro, a newer and more advanced codec, supports multichannel and high resolution audio.

- - Wikimedia

Step-By-Step to Convert AVI to WMA

Interface

Step 1. Download and install the program, then double click it to run it, and then you'll see the main interface of the program.

Load Files

Step 2. Click "Add File(s)" button. Here you can select "Add Video" or "Add Folder" button to add files as you like.

Profile

Step 3. Click the drop-down arrow right beside the "Profile" column and select your desired video format from the drop-down list.

Edit

Step 4. Click "Edit" button to customize the output video like Effect, Trim, Crop, 3D Settings and Watermark.

More Reading