[Thunar-dev] PDF Thumbnailer

[Erlend Davidson]

Benedikt Meurer wrote:
> Erlend Davidson wrote:
>   
>> I want to include a simple PDF thumbnailer for thunar, which uses 
>> ImageMagick.  I know there is already one, but it depends on evince 
>> being installed which would require a number of gnome libraries - not 
>> everyone wants to do this, especially not for a simple thumbnail.
>>
>> The trouble is if I include a thumbnailer which supports a format 
>> already supported by an existing thumbnailer - what happens?  I presume 
>> mine (being added to the system later) would override thunar's default, 
>> which probably isn't the intended option.  If you have evince installed 
>> then I would say it is the best (fastest) means of thumbnailing a PDF.
>>
>> This this in mind I want to propose to Benedict that the .desktop files 
>> for each thumbnailer have another field:
>> X-Thumbnailer-Priority
>> which is a number: 1 being a low priority and anything above that 
>> increasingly higher priority.  The default priority for any thumbnailer 
>> in thunar should be 10, that way when I want to include (for example) 
>> the PDF thumbnailer I can set the priority to be 5... when 
>> /usr/libexec/thunar-vfs-update-thumbnailers-cache-1 is run by the user 
>> the highest priority thumbnailers which have their TryExec found will be 
>> added to the thumbnailer cache.
>>
>> For example if evince is not installed and 
>> /usr/libexec/thunar-vfs-update-thumbnailers-cache-1 is run it,
>> 1. looks at both thunar-thumbnailers' and thunar's (evince) .desktop files
>> 2. sees that evince has a higher priority (because it is faster it 
>> should be given the higher priority)
>> 3. sees that evince-thumbnailer is not on tha $PATH, so uses the 
>> thumbnailer with the next highest priority.
>>
>> This seems like the simplest solution to me, as it only requires the 
>> thunar-vfs-update-thumbnailers-cache-1 command to be updated.
>>
>> This also fixes a problem caused by ffmpeg-thumbnailer, which can 
>> override totem-thumbnailer.
>>     
>
> The GNOME thumbnailers are used by default. Any thumbnailer installed
> via a .desktop file overrides a conflicting GNOME thumbnailer.
But what if, as in the case for a pdf/ffmpeg thumbnailer I want to 
under-ride (as a fallback) the gnome ones?