AVI Files

The AVI (Audio-Video Interleaved) format is the Windows standard for movie files. The .avi file-name extension indicates a Windows AVI movie file.

3ds Max creates an AVI created when you make a preview animation. You can also render your final output to an AVI file. Although 3ds Max produces its highest-quality output by rendering single-frame TGA files or rendering directly to a digital disk recorder, you can still get good results rendering AVI files.

AVI files can be used as input to 3ds Max in several ways, for example:

As animated materials in the Material Editor
As viewport backgrounds for rotoscoping
As input images for compositing in Video Post

Interface

When AVI is the chosen output format, clicking Render or Setup on the Render Output File dialog displays the Video Compression dialog.

Compressor: Use the drop-down list to choose the codec (compressor/decompressor) you want to use to compress the file. You can use any codec that's installed on your system.

Alternatively, you can render uncompressed frames and then use an external application to compress the animation. Video-file compression is a complex subject, with many aspects to consider.
Compression Quality: Available only for certain codecs. When available, use the slider to specify the quality you want. The higher you set the quality, the larger the file size will be.
Keyframe Rate: Available only for certain codecs. When available, use this setting to specify the interval between the delta keyframes used to compare one frame with another and generate in-between frames. Too large an interval will create loss of quality in the AVI file as a whole.
Setup: Available only for certain codecs. Click this button to see any additional options that are specific to the codec. These are vendor specific and vary from codec to codec.