Currently, we are filtering libavformat style ASS packets by checking
whether they are prefixed "Dialogue: ". Unfortunately, comment packets
are demuxed too. These start with "Comment: ", so they are not caught.
Change the filtering, and use the codec ID instead. libavformat uses
"ssa" as codec ID for ASS subtitles, while mpv uses "ass". Also, at
least FFmpeg will change the ASS packet format to the same format mpv
and Matroska use, and identify these with "ass" as codec ID, so this is
works out nicely.
Some of this (fixing timing) is now done in dec_sub.c (although it's
not active for subreader.c code yet - this will be fixed when
subreader.c subs are read through a demuxer wrapper).
Another reason to remove this is that this code doesn't do much good
anymore. libass does handle overlap, and trying to fold overlapping
lines into single subtitle events will prevent libass from handling
this properly.
This fixes the -subfps option (which unfortunately is still useful),
and fixes minor annoying timing errors (which unfortunately still
happen).
Note that none of these affect ASS or image subtitles. ASS is specially
handled: libass loads subtitles as ASS_Track. There are no actual
packets passed around, and sd_ass just uses the ASS_Track.
Disable the --sub-no-text-pp option. It's misleading now and always was
completely useless.
If a subtitle is external, read it completely and add all subtitle
events in advance when the subtitle track is selected. This is done
for text subtitles only. (Note that subreader.c and subtitles loaded
with libass are different and don't have anything to do with this
commit.)
Seems like a completely unnecessary complication. Instead, always add a
1 byte padding (could be extended if a caller needs it), and clear it.
Also add some documentation. There was some, but it was outdated and
incomplete.
This function was called in various places. Most time, it was used
before a seek. In other cases, the purpose was apparently resetting
the EOF flag. As far as I can see, this makes no sense anymore. At
least the stream_reset() calls paired with stream_seek() are completely
pointless. A seek will either seek inside the buffer (and reset the
EOF flag), or do an actual seek and reset all state.
Both converters can output \pos and deal with font sizes, so they assume
a specific script resolution (PlayResX/PlayResY). The implicit
assumption was that a specific resolution was guaranteed. The
MP_ASS_FONT_PLAYRESY constant is connected to this.
Better make it explicit, so that the implicit dependency on
MP_ASS_FONT_PLAYRESY is removed. (Unfortunately, libavcodec sub
converters still don't set PlayResX/PlayResY explicitly, so the value
set by that constant can't be declared as arbitrary yet.)
PlayResY=288 is most likely the SSA natural script resolution (or
something like this?), as well as the libass and VSFilter default.
PlayResX=384 is the fallback value set by libass if PlayResY is set to
288, and PlayResX is unset.
The default style is added by mp_ass_default_track(), but not by
ass_new_track(). Considering this, the previous condition at this point
didn't make much sense anymore: the actual (converted) subtitle format
doesn't matter much for what styling should be applied. What matters is
if the subtitle was originally ASS, or if it was converted to it.
Change the code such that the default style is added if there aren't
any, even after reading sub extradata. (The extradata contains the ASS
header, including the style section.) This might change behavior with
scripts that don't define any styles. The change is either with this
commit or with an earlier commit in this branch, depending on the
situation - there are multiple places where default styles are added
in libass API functions, and it's all a big mess.
Other than with very old or broken files (where different behavior
doesn't matter much), the current code should be pretty safe, though.
Audio and video had their own (very similar) functions to initialize an
AVPacket (ffmpeg's packet struct) from a demux_packet (mplayer's packet
struct). Add a common function for these.
Also use this function for sd_lavc_conv. This is actually a functional
change, as some libavfilter subtitle demuxers add weird out-of-band
stuff as side-data.
When e.g. converting SRT to ASS, we certainly don't want them stretched
by video aspect ratio, even if that's necessary for native ASS
subtitles.
Annoying weird details...
This mirrors commit "sub: remove check_duplicate_plaintext_event()".
That code was basically duplicated. In general, this code is still
needed when doing conversion during demuxing (mostly because you can
seek during demuxing, which will cause duplicate events by replaying).
Normally, libavcodec subtitle converters will output a style header like
this as part of the extradata:
Style: Default,Arial,16,&Hffffff,&Hffffff,&H0,&H0,0,0,0,1,1,0,2,10,10,10,0,0
We don't want that, so use some bruteforce to get rid of them.
Otherwise this could happily open decoders for image subtitles or even
audio/video decoders. AV_CODEC_PROP_TEXT_SUB is a preprocessor symbol,
but it's still better to detect this properly instead of using #ifdef,
because these flags might as well be changed into enums sooner or later.
This allows using some formats that were not supported until now, like
WebVTT.
We still prefer the internal subtitle reader (subreader.c), because
1. Libav, and 2. random things which we probably want to keep, such as
control over formatting, codepage stuff, or various mysterious
postprecessing done in that code.
This means subassconvert.c is split in sd_srt.c and sd_microdvd.c. Now
this code is involved in the sub conversion chain like sd_movtext is.
The invocation of the converter in sd_ass.c is removed.
This requires some other changes to make the new sub converter code work
with loading external subtitles. Until now, subtitles loaded via
subreader.c was assumed to be in plaintext, or for some formats, in ASS
(except in -no-ass mode). Then these were added to an ASS_Track. Change
this so that subtitles are always in their original format (as far as
decoders/converters for them are available), and turn every sub event
read by subreader.c as packet to the dec_sub.c subtitle chain.
This removes differences between external/demuxed and -ass/-no-ass code
paths further.
Add a basic infrastructure for subtitle converters. These converters
work sort-of like decoders, except that they produce packets instead
of subtitle bitmaps. They are put in front of actual decoders.
Start with sd_movtext. 4 lines of code are blown up to a 55 lines file,
but fortunately this is not going to be that bad for the following
converters.
Make the sub decoder stuff independent from sh_sub (except for
initialization of course). Sub decoders now access a struct sd only,
instead of getting access to sh_sub. The glue code in dec_sub.c is
similarily independent from osd.
Some simplifications are made. For example, the switch_id stuff is
unneeded: the frontend code just has to make sure to call osd_changed()
any time subtitles are switched.
This is also preparation for introducing subtitle converters. It's much
cleaner to completely separate demuxer header/renderer glue/decoders
for this purpose, especially since sub converters might completely
change how demuxer headers have to be interpreted.
Also pass data as demux_packets. Currently, this doesn't help much, but
libavcodec converters might need scary stuff like packet side data, so
it's perhaps better to go with passing packets.
Subtitle files are opened in mplayer.c, not using the demuxer
infrastructure in general. Pretend that this is not the case (outside of
the loading code) by opening a pseudo demuxer that does nothing. One
advantage is that the initialization code is now the same, and there's
no confusion about what the difference between track->stream,
track->sh_sub and mpctx->sh_sub is supposed to be.
This is a bit stupid, and it would be much better if there were proper
subtitle demuxers (there are many in recent FFmpeg, but not Libav). So
for now this is just a transition to a more proper architecture. Look
at demux_sub like an artifical limb: it's ugly, but don't hate it - it
helps you to get on with your life.
This was broken with 84829a4 "Merge branch 'osd_changes' into master".
The new OSD/subtitle code never respected the --sub-forced-only option,
and the old code containing the code for this was removed in fd5c4a1.
This unifies the subtitle rendering path. Now all subtitle rendering
goes through sd_ass.c/sd_lavc.c/sd_spu.c.
Before that commit, the spudec.h functions were used directly in
mplayer.c, which introduced many special cases. Add sd_spu.c, which is
just a small wrapper connecting the new subtitle render API with the
dusty old vobsub decoder in spudec.c.
One detail that changes is that we always pass the palette as extra
data, instead of passing the libdvdread palette as pointer to spudec
directly. This is a bit roundabout, but actually makes the code simpler
and more elegant: the difference between DVD and non-DVD dvdsubs is
reduced.
Ideally, we would just delete spudec.c and use libavcodec's DVD sub
decoder. However, DVD playback with demux_mpg produces packets
incompatible to lavc. There are incompatibilities the other way around
as well: packets from libavformat's vobsub demuxer are incompatible to
spudec.c. So we define a new subtitle codec name for demux_mpg subs,
"dvd_subtitle_mpg", which only sd_spu can decode.
There is actually code in spudec.c to "assemble" fragments into complete
packets, but using the whole spudec.c is easier than trying to move this
code into demux_mpg to fix subtitle packets.
As additional complication, Libav 9.x can't decode DVD subs correctly,
so use sd_spu in that case as well.
This was once needed to handle subtitle packages coming from a demuxer,
where seeking back might repeat previous events. This doesn't happen
anymore, and this code is used to convert complete files. So if there
are any duplicate lines, they must have been duplicated in the file,
and the old subtitle renderer would have shown them twice as well.
Today checking for duplicate events happens in sd_ass.c (and has been
for a while). There's no reason to keep this code, and it actually
causes trouble. Loading big subtitle files is extremely slow because
this makes adding n subtitles O(n^2).
The -no-ass switch used to disable any use of libass for text subtitles.
This is not really the case anymore, because libass is now always
involved when rendering text. The only remaining use of -no-ass is
disabling styling or showing subtitles on the terminal. On the other
hand, the old subtitle rendering path is a big reason why the subtitle
code is still a big mess with an awful number of obscure special cases.
In order to simplify it, remove the old subtitle rendering code, and
always go through sd_ass.c. Basically, we use ASS_Track as central data
structure for storing text subtitles instead of struct sub_data. This
also makes libass mandatory for all text subs, even if they are printed
to the terminal in -no-video mode. (We could add something like sd_text
to avoid this, but it's not worth the trouble.)
struct sub_data and subreader.c are still around, even its ASS/SSA
reader. But struct sub_data is freed right after converting it to
ASS_Track. The internal ASS reader actually can handle some obscure
cases libass can't, like files encoded in UTF-16.
These were found by the cppcheck and scan-build static analyzers. Most
of these aren't interesting (the 2 previous commits fix some interesting
cases found by these analyzers), and they don't nearly fix all warnings.
(Most of the unfixed warnings are spam, things MPlayer never cared
about, or false positives.)
"%[,.:]" conversion was used with a buffer that could be shorter than
the matched string. Suppress assignment of the conversion since the
value wasn't used anyway, and also limit match length to 1 as it
doesn't look like the intent was to match longer runs of the
characters.
Merged from mplayer2 commit 5cb9aac. Note that the other half of the
mplayer2 commit is already part of the mpv commit d98e61e. (I'm not
sure why. The mplayer2 commit date precedes mpv's, but was pushed long
after the mpv change was pushed; either one of the dates is wrong, or
we did the same work twice - in that case, thanks a lot...)
This broke .srt subtitles on gcc-4.8. The breakage was relatively
subtle: it set all hour components to 0, while everything else was
parsed successfully.
But the problem is really that sscanf wrote 1 byte past the sep
variable (or more, for invalid/specially prepared input). The %[..]
format specifier is unbounded. Fix that by letting sscanf drop the
parsed contents with "*", and also make it skip only one input
character by adding "1" (=> "%*1[...").
The out of bound write could easily lead to security issues.
Also, this change makes .srt subtitle parsing slightly more strict.
Strictly speaking this is an unrelated change, but do it anyway. It's
more correct.
The old OSD font was a PostScript Type 1 font. Convert it to OpenType
to work around a fontconfig bug [1]. OpenType is a more modern format,
and the font file is quite a bit smaller, so this is actually a nice
change.
The conversion was done by opening the font with fontforge and saving
it as OpenType (CFF). fontforge showed a warning when doing this:
The font contains errors.
Self Intersecting
Bad Private Dictionary
These seem to be harmless.
[1] https://bugs.freedesktop.org/show_bug.cgi?id=63922
Usually SubRip files are not expected to contain ASS override tags,
but unfortunately these files seem to become more common. Example from
a real file:
1
00:00:00,800 --> 00:00:15,000
{\an8}本字幕由 {\c&H26F4FF&}ShinY {\c&HFFAE1A&}深影字幕组{\c&HFFFFFF&} 原创翻译制作
subassconvert.c escaped '{', so that libass displayed the above line
literally.
Try to apply a simple heuristic to detect whether '{' is likely to
start an ASS tag: if the string starts with '{\', and there is a
closing '}', assume it's an ASS tag, otherwise escape the '{' properly.
If it's a likely ASS tag, it's passed through to libass.
The end result is that the above script is displayed in color, while at
the same time legitimate uses of '{' and '}' should work fine. We assume
that nobody uses {...} for commenting text in SubRip files. (This kind
of comment is popular and legal in ASS files, though.)
Get rid of the 1-char subtitle type field. Use sh_stream->codec instead
just like audio and video do. Use codec names as defined by libavcodec
for simplicity, even if they're somewhat verbose and annoying.
Note that ffmpeg might switch to "ass" as codec name for ASS, so we
don't bother with the current silly "ssa" name.
These require bleeding edge libass (latest git version), and will be
ignored otherwise.
I'm not sure about the blur factor and scaling. The ASS/VSFilter
semantics for blur scaling are a bad mess. Might require further
investigation.
Drawing the bar with vector drawings (instead with characters from the
OSD font) offers more flexibility and looks better. This also adds
chapter marks to the OSD bar, which are visible as small triangles on
the top and bottom inner border of the bar.
Change the default position of the OSD bar below the center of the
screen. This is less annoying than putting the bar directly into the
center of the view, where it obscures the video. The new position is
not quite on the bottom of the screen to avoid collisions with
subtitles.
The old centered position can be forced with ``--osd-bar-align-y=0``.
Also make it possible to change the OSD bar width/height with the new
--osd-bar-w and --osd-bar-h options.
It's possible that the new OSD bar renders much slower than the old
one. There are two reasons for this: 1. the character based bar
allowed libass to cache each character, while the vector drawing forces
it to redraw every time the bar position changes. 2., the bar position
is updated at a much higher granularity (the bar position is passed
along as float instead of as integer in the range 0-100, so the bar
will be updated on every single video frame).
The old names have been deprecated a while ago, but were needed for
supporting older ffmpeg/libav versions. The deprecated identifiers
have been removed from recent Libav and FFmpeg git.
This change breaks compatibility with Libav 0.8.x and equivalent
FFmpeg releases.
Removes almost every global variabel in vo.h and puts them in a special struct
in MPOpts for video output related options.
Also we completly remove the options/globals pts and refresh rate because
they were unused.
wm4
Paul B Mahol
Uoti Urpala
Stefano Pigozzi
Alexander Preisinger