@dum. If I understood your intention correctly, you will need to do the following:
1. Get a win32 ffmpeg build (http://arrozcru.no-ip.org/ffmpeg_builds/) (prefer the gpl-static download, it has fewer files).
2. Create one folder that will contain the avs script and the ffmpeg executable & assoc. dlls. Copy all files from the \bin subfolder where your have unpacked ffmpeg to this folder.
2. Put the following lines at the start of your avs script:
src = Import("current_file.txt")
AviSource(src)
After that the "last" special variable will contain the source video (from the '''echo "%%f">current_file.txt''' line in step 3 below).
3. Write a simple batch file following the template below (assuming you named your avs file as "myscript.avs", else change the name as wished):
@echo off
set src_folder=%1
set dst_folder=%2
for %%f in (%src_folder%\*.avi) do (
echo "%%f">current_file.txt
ffmpeg -i myscript.avs -vcodec xvid -acodec mp3 -b 800kb -ab 128 %dst_folder%\%%~nf.avi
)
If you want to encode to another format and not xvid, look at the available options of ffmpeg. It will help if you type ffmpeg>options.txt in the command prompt and read the file with a text editor; it is quite long for a console screen. At the same url of step 1 there is also a handy utility, WinFF, which you can use to find out the correct ffmpeg command line for a number of presets.
4. Call the batch file (say you named it "batchenc.cmd") as:
batchenc <relative-path-to-source-folder> <relative-path-to-destination-folder>
It will help if you put the input/output avis to subfolders of the folder where the main avs script, the batch file and ffmpeg are. If for example you make an "input" and "output" folder respectively, then you just have to type:
batchenc input output
5. That's all. If the preparation steps are done properly, then after running batchenc you will have a nice set of encoded files filtered with the same settings :).
Note 1: with the same procedure you can also use other command-line encoders that support avs files such as avs2avi, etc. All is needed is to change the line that calls the encoder.
Note 2: If it is the case that you have a text file with a listing of filenames (one per line), then you should replace the for... line in the batch file (step 3) with:
for /F %%f in (%1) do (
and call the batch file (step 4) as:
batchenc <path-to-list-file> <relative-path-to-destination-folder>
If the listing contains also other items in each line look at the help in for command (type for /? at the command prompt) to see ways to accurately parse each line.