ELAN lagging and then crashing

Hi there Han and team, I am using ELAN 6.4 to synchronize two videos and then code behaviors. When loading ELAN it says there are errors with my media drives/java script drives that they can’t play the file type. After media synchronization mode I enter annotation mode but whenever a period of high activity in the video appears the videos start lagging behind each other and then the pause button freezes and ELAN eventually crashes saying “child process exited with code 3221225477”.

I use w dell PC with windows 10 and 8 GB RAM. My PI on mac books have zero trouble it’s just me at home. Can equipment or wifi speed affect ELAN performance?

How do I reduce lag?


I’m not sure if I understand the situation correctly. You mention you see an error concerning media drives/java script drives (I don’t know how messages concerning Javascript could be produced?), does this mean the media files are on a remote drive? In that case wifi speed can indeed play a role.

Despite the message, the videos apparently do load? Can you add some more information on the type of media files, where they are and what size they are etc.? There seems to be a link between the contents of the videos and the lagging, which is a bit surprising, but maybe the decoding requires more resources when a lot changes between video frames?

The exit code seems to be quite common, many reports can be found, but it is unclear what actually causes it in ELAN, in this situation. I don’t suppose there is more detailed information in the ELAN log files (elan0.log, elan1.log etc. in ELAN’s data folder) or maybe in the EventViewer? If so, maybe you can send it by email to me (han.sloetjes AT mpi.nl)?


Yeah, the files did indeed load. They are EAF files that are 73.6 KB. It seems to be a lag between video one staying synchronized with video 2. I emailed the error text to you from the ELAN.1log

Thanks, the log doesn’t reveal the cause of the main problem, but some recommendations can be made based on its contents:

  • sometimes a .pfsx (ELAN preferences file) becomes linked as a media file (either by accident or because of a bug?). ELAN then tries to create a media player for it, probing all available media frameworks. This will fail and a message about not being able to create a player will be shown. It is best to remove the .pfsx from the linked media via File->Linked Files....

  • creating and updating the Spectrogram viewer consumes part of the computer resources, especially if only video (mp4) files are linked and the audio track has to be decoded from the video. It is best to extract a .wav from the video and link it as another media file or hide the Spectrogram viewer (and maybe the Signal viewer as well) in case it isn’t really used in the annotation process.

  • we have indications that play back performance sometimes decreases if the linked media files are in a shared folder (e.g. a OneDrive folder).

  • the main problem might be connected to error message in the log, like this:
    NATIVE: MMFPlayer.Invoke: failed to process the media event (-1072875854, 0xC00D36B2)
    The source of these messages is still unknown, unfortunately.