Move the declarations of the "report_error()" and "set_error_cb()"
functions and the "verbose" variable to errorhelper.h.
Thus, error-reporting translation units don't have to import the
big dive.h header file.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
In the error messages shown when failing to start ffmpeg, instruct
the user to set the correct executable in the preferences.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
Extract thumbnails using ffmpeg.
Behavior is controlled by three new preferences fields:
- extract_video_thumbnails (bool): if true, thumbnails are calculated.
- extract_video_thumbnail_position (int 0..100): position in video
where thumbnail is fetched.
- ffmpeg_executable (string): path of ffmpeg executable.
If ffmpeg refuses to start, extract_video_thumbnails is set to false
to avoid unnecessary churn.
Video thumbnails are marked by an overlay.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>