I noticed extremely slow loading of an mkv that's on an SMB share (gigabit network, no I/O load on the other side; consistently 100MB/s transfers). The client starts up immediately but it takes 40 seconds on average for the video to start playing. This particular mkv has 15 vobsub tracks totalling 94MB (mkv is in total 7.7GB). I extracted just the a/v tracks and that video starts playing instantly. I then extracted just the subs into an mks file and tried to open it with vlc, and that takes about 40 seconds as well. Start time is fine (maybe 1-2 seconds; not great but livable) for the full mkv on a local disk. mplayer does not exhibit this problem.
Given these conditions it seems that either a large number of vobsub tracks or, possibly, large overall size of muxed subs, load extremely slowly across a network share in vlc. I don't think there's anything wrong environmentally since file transfers are fast and with the subs removed it is also fast.
I can't upload a sample since my connection is much too slow to upload 100MB, but I was able to easily reproduce the problem by taking a vobsub track from a different mkv (to ensure it's not corruption on the original mkv) and appending it to itself ten times into a new mks file.
I want to say this is a regression because I have quite a few mkvs like this and I don't remember having trouble with them before, but I can't say for sure.
Log snippet:
Code: Select all
mkv debug: original frame size vobsubs: 1920x1080
mkv debug: vobsub palette read
mkv debug: | | + Track Entry
mkv debug: | | | + Track Number=16
mkv debug: | | | + Track UID=3193311379
mkv debug: | | | + Track Type=subtitle
mkv debug: | | | + Track Default=0
mkv debug: | | | + Track Lacing=0
mkv debug: | | | + Track CodecId=S_VOBSUB
mkv debug: | | | + Track CodecPrivate size=348
mkv debug: | | | + Track Language=`swe'
mkv debug: | | | + Content Encodings
mkv debug: | | | | + Content Encoding
mkv debug: | | | | | + Content Compression
mkv debug: original frame size vobsubs: 1920x1080
mkv debug: vobsub palette read
mkv debug: | | + Seek
mkv debug: | - cues at 97747676
mkv debug: | + Cues
<-- 40 seconds here -->
mkv debug: | - loading cues done.
mkv debug: | | + Seek
mkv debug: | - tags at 98537917
mkv debug: | + Tags
mkv debug: + Tag