Matroska or "MKV" video file thumbnails not showing in Caja!

[eor2004]

Hi guys!, I have a little issue in MATE, the issue is that in Caja, the file manager for MATE DE, some Matroska or "MKV" video file thumbnails shows and others not in caja as you can see in the picture, does somebody knows what can I do to make all the Matroska (MKV) video thumbnails to show?

[eor2004]

Have tried all the suggested possible solutions here but to no avail.
http://forums.mate-desktop.org/viewtopic.php?f=2&t=3003

[eor2004]

Now I'm running Sabayon MATE 1.8 but no joy, still no fix for this issue, if I run "sudo caja" and open the folder as "root" this is the output I get from terminal:

Code: Select all

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2013%20-%20Strive%20for%20the%20Grand%20Championship.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6659): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6659): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2014%20-%20Save%20a%20Small%20Life.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6673): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2015%20-%20Assassination%20Group%20of%20Fire.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6687): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6687): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2016%20-%20A%20Promise%20From%20the%20Heart.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6701): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6701): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2017%20-%20Fly%20to%20Your%20Dreams.mkv: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2019%20-%20Raijuta's%20Ambition.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6785): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2023%20-%20Sanosuke's%20Betrayal.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6798): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6798): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2024%20-%20Midnight%20Battle.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6812): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6812): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2025%20-%20The%20Crimson%20Pirate.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6854): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2028%20-%20Prelude%20To%20The%20Impending%20Fight.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6868): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6868): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6868): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6868): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6924): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6924): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2033%20-%20For%20The%20Title%20Of%20Strongest_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6966): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2036%20-%20Across%20The%20Boundary%20Between%20Edo%20And%20Meiji_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6980): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:6980): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2037%20-%20Shock!%20Reverse%20Blade%20Sword%20Broken_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:6994): CRITICAL **: gst_video_codec_frame_ref: assertion 'frame != NULL' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2038%20-%20Sanosuke's%20Secret%20Training_new.mkv: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2040%20-%20A%20Killer%20Without%20Mercy_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7049): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7049): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2042%20-%20The%20Formation%20of%20an%20Alliance.mkv: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2045%20-%20As%20If%20To%20Fly_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7119): CRITICAL **: gst_video_codec_frame_ref: assertion 'frame != NULL' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2047%20-%20Crash!%20The%20Lethal%20Punch,%20Futae%20No%20Kiwami.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7160): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7160): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2050%20-%20The%20Promised%20Time%20Has%20Come_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7174): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7174): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2051%20-%20Wake%20Up%20Now!_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7188): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7188): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2052%20-%20To%20Make%20A%20Miracle_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7216): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7216): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2054%20-%20Hiten%20Versus%20Shukuchi_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7244): CRITICAL **: gst_video_codec_frame_ref: assertion 'frame != NULL' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2056%20-%20A%20Duel%20With%20An%20Extreme%20Moment.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7258): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7258): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2057%20-%20Two%20Men%20At%20The%20End%20Of%20An%20Era.mkv: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2058%20-%20The%20Age%20Chooses%20Shishio.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7286): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7286): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2059%20-%20Not%20Out%20Of%20Luck.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7300): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2060%20-%20Chosen%20For%20Victory.mkv: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2061%20-%20The%20Juppongatana%20Who%20Remain_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7356): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7356): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2064%20-%20The%20Birthplace%20Of%20Yahiko_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7398): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7398): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2067%20-%20Gleaming%20Blade%20of%20Legends!_new.mkv: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2069%20-%20Battlefield%20of%20Shimabara_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7454): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7454): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2071%20-%20The%20Conspiracy%20of%20Kaiou_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7468): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2072%20-%20Days%20of%20Remorse_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7482): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7482): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2073%20-%20The%20Sneering%20Demon_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7496): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7496): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2074%20-%20Sanosuke's%20Tears_new.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7524): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7524): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2076%20-%20Bon%20Voyage.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7538): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2079%20-%20Katsu%20Kaishi%20And%20Kenshin.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7608): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2082%20-%20Kaishu%20Katsu's%20Determination.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7622): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7622): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2083%20-%20Yutaro%20Returns.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7650): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2085%20-%20A%20Straying%20Journey.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7664): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7664): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2086%20-%20The%20Three%20Sanada%20Demons.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7706): CRITICAL **: gst_video_codec_frame_ref: assertion 'frame != NULL' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2089%20-%20To%20My%20Angel%20Misao.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7747): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7747): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2092%20-%20Tokyo%20Under%20Martial%20Law!.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7761): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

** (totem-video-thumbnailer:7761): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2093%20-%20The%20Enemy%20Awaits%20In%20Senjo%20Gahara.mkv: Unrecognized image file format

** (totem-video-thumbnailer:7789): CRITICAL **: gst_video_codec_frame_unref: assertion 'frame->ref_count > 0' failed

(caja:6178): MateDesktop-WARNING **: Unable to create loader for mime type video/x-matroska: Unrecognized image file format

(caja:6178): MateDesktop-WARNING **: Error creating thumbnail for file:///home/ezequiel/Videos/Rurouni%20Kenshin%20(Dual-Audio)/Rurouni%20Kenshin%2095%20-%20End%20Of%20Wanderings.mkv: Unrecognized image file format

[toppy]

Hi ! .. I am not certain if this applies to MKV files but I have had a similar issue with some H.264 movie files .. it seems that some are written with the index at the end of the file: this stops progressive playback and (in my case) the generation of thumbnails for that file.
The solution I found was to re-write the movie file with QTIndexSwapper, a free Adobe Air plugin available here .. http://renaun.com/blog/code/qtindexswapper/ ... which moved the index to the beginning of the file. This does mean of course that being an Adobe product you have to run it on Windoze .. I run it in a VM for occasional uses.
Hope this works for you .. If I am totally wrong, I apologize and hope someone will correct me !

[eor2004]

I have made a video using recordmydesktop, in it you will see how the MKV video file thumbnail shows up by simply copying the video file to a new folder or just by removing special characters in the video file name or renaming the video file, very strange indeed!

Please download if you want more clear video: https://www.dropbox.com/s/39s24gt4r5zjb ... 20%231.ogv

@ toppy: Thank you for your answer, will look into that later.