[mythtv-users] Subtitle clarity

Jim Stichnoth stichnot at gmail.com
Thu Jun 7 06:21:08 UTC 2012


On Wed, Jun 6, 2012 at 4:46 PM, Shawn king <slackerlinux85 at gmail.com> wrote:
> On 06/07/2012 07:08 AM, Jim Stichnoth wrote:
>
> On Wed, Jun 6, 2012 at 1:59 PM, Alexander Fisher <alex at alexfisher.me.uk>
> wrote:
>
> On 6 June 2012 20:49, Jim Stichnoth <stichnot at gmail.com> wrote:
>
> On Wed, Jun 6, 2012 at 8:44 AM, Michael T. Dean <mtdean at thirdcontact.com>
> wrote:
>
> On 06/06/2012 11:32 AM, Alexander Fisher wrote:
>
> Does anybody else have issues with some subtitles (from dvd rips),
> being really difficult to read?
>
> I started watching 'Jean de Florette', with English titles turned on,
> but gave up until I figured out how to fix this issue.
>
> The titles are large enough and appear in the correct part of the
> screen, but they look really odd.  They're grey, with a thin white
> edging.  With no antialiasing, this looks awful.
> The same mkv file played with VLC is *much* more pleasing with solid
> white titles that are easier to follow.
>
> Before I open a ticket and attach a sample, I thought I'd check to see
> if it was a known issue.
>
> DVD subtitles are image-based subtitles.  It's likely a problem with either
> bad mastering of the DVD or the scaling of the images and/or overlaying them
> on the video that's making them bad.
>
> In other words, since they're not text-based, it's not a font problem we can
> fix.
>
> It is possible that there is some kind of color palette/transparency issue
> in the code, but you should definitely try playing back that DVD with
> another DVD player to see if it's just as bad there.
>
> From the description, I would bet on a color palette issue, either
> from a MythTV problem or from an underlying ffmpeg problem.  I haven't
> seen this issue before.  Please do create a new ticket with a sample
> and I will investigate.
>
> Hi Jim
>
> Firstly, thanks for spending so much time looking into all the recent
> subtitle issues I've been reporting.
> It's very much appreciated.  I've opened a ticket with a link to a 60
> second sample.
> http://code.mythtv.org/trac/ticket/10811
>
> Alex,
>
> Thanks for your help in improving MythTV's subtitle experience.  I'll
> take a look at the sample as soon as I get in front of a TV.
>
> Jim
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://www.mythtv.org/mailman/listinfo/mythtv-users
>
> this is a ffmpeg issue thats been fixed with the latest merge in 0.26. i had
> the same issue with alot of my videos white border with grey fill this
> commit to ffmpeg should be the one that needs to be backported(i replaced
> dvdsubdec.c instead of backporting but im quite sure thats the right commit
> that fixes it)
>
> dvdsubdec: Support palette information for vobsub's stored as text in
> extradata

Indeed, the subtitles in the sample display quite reasonably on my
system running Master.  (Unfortunately I'm not in a good position to
test 0.25-fixes.)

I'll see about a potential backport, but at a minimum, you can expect
the problem to be fixed in 0.26.

Jim


More information about the mythtv-users mailing list