Sorry I can't type chinese. Hope you understand what i said.
Yes, you can convert mp4 to avi. You need:
1)3ivx codec
2)graphedit
3)Virtualdub
Step 1:
Install 3ivx
Step 2:
Use graphedit to render the mp4.
Remove "video render" and "default direct sound device" from the graph. Connect the decoded A/V stream to "AVI muxer" then output to "file writer".
You now got a RAW AVI file.
Step 3:
Open the raw avi file, recompress with virtualdub with whatever codec you like.
Note:
I don't understand why you want to convert mp4 to avi, their quality should be the same if you make it from same source. However, you can't simply repack a mp4 to avi without recompression, this cause quailty loss.
