title: Bulk converting MKV files to MP4 with AAC using a Windows batch file
body: <p>So I have been trying for days to work out how to do this and this site has helped me but I am still stuck. </p>
  
  <p>I basically want to run a batch file and it goes through a folder including all subdirectories and changes the container of all mkv files to mp4 converting the sound to AAC if necessary. Preferably it will create the new mp4 file in the same place with the same name and then delete the mkv. </p>
  
  <p>All I have so far is this which if I place it in a certain folder will create the mp4's in a specified folder called newfiles. I am not sure if I have used libfaac correctly either. Would greatly appreciate any advice. I would have liked to use libfdk_aac but I have tried everything to get it and I cant find it. </p>
  
  <pre><code>for %%a in ("*.mkv") do C:\ffmpeg\bin\ffmpeg -i "%%a" -vcodec copy -acodec libfaac "Z:\newfiles\%%~na.mp4"
  pause
  </code></pre>