Thumbnails of videos and other file types

Thumbnail Helpers

One of the features of ROX-Filer is the ability to provide thumbnail images for of certain files. These are small images based on the content of the file and used to replace the default type icon for that file in ROX-Filer windows. You can see this effect by viewing a directory containing JPEG files and turning on thumbnail mode (Display => Show Thumbnails, normally bound to ctrl-T). ROX-Filer shows "thumbs" in the titlebar when thumbnail mode is on.

By itself ROX-Filer can generate thumbnails for the most common image file types

* JPEG
* PNG
* GIF
* SVG (normally)
* and a few others

However it does not support all image types, nor does it generate thumbnails for other types of file such as video or font files. To do so would increase the size of the program and slow it down. Also the file types that the user would want thumbnailing would vary from user to user.

The solution is to allow ROX-Filer to call external programs which are capable of generating thumbnails for certain types. The user can then enable or disable whichever types they wish to thumbnail.

Available thumbnail helpers include:

* VideoThumbnail: many types of video files
* MagickThumbnail: image types not handled internally

The helper applications are normally implemented as Library Directories.

Known problems

I installed VideoThumbnail/MagickThumbnail but it doesn't work
Did you remember to let it install handlers for its types?
I have a helper for a type but it is never called
If the helper is a Library Directory check that it and the AppRun file inside are owned by the same user.
When I click on "Install handlers" it gives me this error: OSError: [Errno 17]
This is a bug in some recent versions of ROX-Lib, fixed in version 2.0.2.
I upgraded to ROX-Lib version 2.0.2 but I still get the error
You need to clean up the files left behind by previous installation attempts, such as ~/.config/rox.sourceforge.net/MIME-thumb/application_ogg and ~/.config/rox.sourceforge.net/MIME-thumb/application_ogg.tmp (replace ~/.config with your $XDG_CONFIG_HOME if it is different).