Using Avisynth and VirtualDub to join BMP to AVI

1. Download Avisynth and install it.
2. Download VirtualDub and unzip / install it.
3. You need to have a set of BMP files with sequential numbering.  Refer to this post for how to do that.
4. In the folder containing the bitmaps, create a text file.  Call it READ.AVS (it must have AVS extension).
5. Open it in Notepad and put the following line into the file:
   ImageSource("%04d.bmp", start = 1, end = 1800, use_DevIL = true)
6. The above syntax is for files with 4 digit filenames, starting at 0001.bmp and ending at 1800.bmp (obviously, if you have more or less frames, change the 1800 value accordingly).
7. Open VirtualDub
8. Open the READ.AVS file that you created.
9. Now you should be able to save this file from VirtualDub to an AVI.  Here is some quick settings:
   Video - Direct Stream Copy
   Audio - No audio
10. Go File - Save as AVI
11. Put your AVI somewhere with plenty of disk space - it could become huge.

 

You may also want to refer to the master post entitled Distributed Parallel Rendering in Revit.