It's not about TidyPics or Blog plugins but File plugin.

Every time you upload a file, an event appears in the activity.

It doesn't matter where you do it when creating a blog or when uploading a file normally.

I haven't found a way to do this using Elgg API (none of the hooks I know work for files).

Therefore, I can advise to use the custom view:

/mod/my_plugin/view/default/river/object/file/create.php

With empty code:

<?php

You can take my plugin from here so as not to create a new one and put the above file there.

Thank you, Nikolai. Much appreciated.

Hello iionly,

Thanks for your prompt response. I've been on this all afternoon and still no joy. Ffmpeg just appears to stop after the creation of the png thumbnail. I'm also using Tidypics and that is working fine. Cron is enabled and running, the files exist, I can video convert via the command line using the domain user and the data directory group includes www-data.

I'll keep at it and let you know when I've succeeded. It's probably something embarrassingly simple :) 

Thanks again.

It's working now. My fault :(

I finally tracked it down to an orphan record in the queue.db (I don't know how it got there). This appeared to cause a problem in: /izap_videos/views/default/izap_videos/admin/getQueue.php Line 33 with a call to PHP filesize(). As the orphan record was first in the queue I believe it prevented the queue from running the conversion on the other videos. What led me to this was attempting to delete the first record in the queue threw a critical error.

Anyway, if anyone else should have problems converting videos and a "Warning: filesize() [function.filesize]: stat failed for..." is logged in the error.log and deleting a video in the queue causes a critical error it could be the result of an orphan record in the queue.db. 

Thanks for sharing.

Reposted on the Elgg Channel.