Merges pull request #1094, with some minor changes. mpv expects IEEE,
and IEEE allows divisions by 0 for floats, so these shouldn't actually
be a problem, but do it anyway for the sake of clang.
Signed-off-by: wm4 <wm4@nowhere>
This is a deadlock caused by a lock order issue: sub/osd.c locks the OSD
first, then the subtitle decoder lock. player/sub.c does the reverse.
Fix this by discussing away the requirement for locking (see below),
which allows us to drop the broken sub lock. sub_get_text() still
acquires and releases the sub decoder lock, but it's not held at the
same time as the OSD lock anymore, so it should be fine.
Originally, the sub lock was acquired because sub_get_text() returns a
pointer to a mutable string. We simply declare that it's ok to call it
unlocked, as long as only 1 thread accesses it, which works out fine in
this case.
bstr.c doesn't really deserve its own directory, and compat had just
a few files, most of which may as well be in osdep. There isn't really
any justification for these extra directories, so get rid of them.
The compat/libav.h was empty - just delete it. We changed our approach
to API compatibility, and will likely not need it anymore.
It makes no sense to set the packet duration, because libavcodec doesn't
know the timebase. And in fact, no subtitle decoder accesses the packet
duration, except text subtitle converters, which are not relevant here.
So this code did nothing - drop it.
Also fix a blatantly incorrect comment.
sub_reset() was called on cycling subtitle tracks and on seeking. Since
we don't want that subtitles disppear on cycling, sd_lavc.c didn't clear
its internal subtitle queue on reset, which meant that seeking with PGS
subtitles could leave the subtitle on screen (PGS subtitles usually
don't have a duration set).
Call it only on seeking, so we can also strictly clear the subtitle
queue in sd_lavc.
(This still can go very wrong if you disable a subtitle, seek, and
enable it again - for example, if used with libavformat that uses "SSA"
style demuxed ASS subtitle packets. That shouldn't happen with newer
libavformat versions, and the user can "correct" it anyway by executing
a seek while the subtitle is selected.)
Something like "char *s = ...; isdigit(s[0]);" triggers undefined
behavior, because char can be signed, and thus s[0] can be a negative
value. The is*() functions require unsigned char _or_ EOF. EOF is a
special value outside of unsigned char range, thus the argument to the
is*() functions can't be a char.
This undefined behavior can actually trigger crashes if the
implementation of these functions e.g. uses lookup tables, which are
then indexed with out-of-range values.
Replace all <ctype.h> uses with our own custom mp_is*() functions added
with misc/ctype.h. As a bonus, these functions are locale-independent.
(Although currently, we _require_ C locale for other reasons.)
Search $XDG_CONFIG_HOME and $XDG_CONFIG_DIRS for config files.
This also negates the need to have separate user and global variants of
mp_find_config_file()
Closes#864, #109.
Signed-off-by: wm4 <wm4@nowhere>
Until now, bitmap subtitles were decoded at "some" point, and then
simply replaced the old subtitle. Although the subtitle is selected
by time (PTS), it could happen that a subtitle was replaced too early.
One consequence is that this might lead to flicker even if the
subtitles are timed to follow each other without a gap (although most
subtitles are explicitly timed to introduce such a gap). With this
commit the past 4 subtitles are kept (instead of 1), so that the
correct one can be picked by time. This should fix the aforementioned
cases, but more importantly will allow demuxing/decoding and video
display to be somewhat asynchronous.
Still missing: somehow making sure the correct range of decoded
subtitles is available, instead of just passing along whatever comes
from the demuxer, and hoping that 4 queued subtitles are enough. But it
should certainly be good enough for now.
This removes a check that resets the subtitles if the PTS is 5 minutes
before the end of the current subtitle; this is probably not needed.
Until now, failure to allocate image data resulted in a crash (i.e.
abort() was called). This was intentional, because it's pretty silly to
degrade playback, and in almost all situations, the OOM will probably
kill you anyway. (And then there's the standard Linux overcommit
behavior, which also will kill you at some point.)
But I changed my opinion, so here we go. This change does not affect
_all_ memory allocations, just image data. Now in most failure cases,
the output will just be skipped. For video filters, this coincidentally
means that failure is treated as EOF (because the playback core assumes
EOF if nothing comes out of the video filter chain). In other
situations, output might be in some way degraded, like skipping frames,
not scaling OSD, and such.
Functions whose return values changed semantics:
mp_image_alloc
mp_image_new_copy
mp_image_new_ref
mp_image_make_writeable
mp_image_setrefp
mp_image_to_av_frame_and_unref
mp_image_from_av_frame
mp_image_new_external_ref
mp_image_new_custom_ref
mp_image_pool_make_writeable
mp_image_pool_get
mp_image_pool_new_copy
mp_vdpau_mixed_frame_create
vf_alloc_out_image
vf_make_out_image_writeable
glGetWindowScreenshot
We certainly don't want to maintain and improve the internal converter,
but we still need the internal one for Libav. (In the Libav case,
demux_subreader.c will be used to read the MicroDVD file.)
Let the VOs draw the OSD on their own, instead of making OSD drawing a
separate VO driver call. Further, let it be the VOs responsibility to
request subtitles with the correct PTS. We also basically allow the VO
to request OSD/subtitles at any time.
OSX changes untested.
While I'm not very fond of "const", it's important for declarations
(it decides whether a symbol is emitted in a read-only or read/write
section). Fix all these cases, so we have writeable global data only
when we really need.
(The old "force" choice of that option is renamed to "force-default".)
This allows overriding native ASS script subtitle styles with the style
provided by the --sub-text-* options (like --sub-text-font etc.). This
is disabled by default, and needs to be explicitly enabled with the
--ass-style-override=force option and input property.
This uses in fact exactly the same options (--sub-text-*) and semantics
as the ones used to configure unstyled text subtitles.
It's recommended to combine this with this in the mpv config file:
ass-force-style="ScaledBorderAndShadow=1" # work around dumb libass behavior
Also, adding a key binding to toggle this behavior should be added,
because overriding can easily break:
L cycle ass-style-override
This would cycle override behavior on Shift+L and allows quickly
disabling/enabling style overrides.
Note: ASS should be considered a vector format rather than a subtitle
format. There is no easy or reliable way to determine whether the style
of a given subtitle event can be changed without destroying visuals or
not. This patch relies on a simple heuristic, which often works and
often breaks.
This might shift bits into the sign, which is undefined behavior. Making
the right operand unsigned was supposed to help with this, but it seems
it did nothing, and C99 makes the result type dependent on the left
operand only.
This used an unnamed union, which is allowed in GNU C and C11, but not
C99. This broke the build with some older compilers.
Replaces pull request #744.
The --ass-styles option is implemented by calling ass_read_styles().
This function can take a codepage (so libass will use iconv to convert
it). This was implemented before our --subcp option was changed, and
this code was not updated. Now libass fails opening iconv, because
--subcp is not always (and not by default) a valid iconv codepage.
Just always pass NULL, which means the file passed to --ass-styles must
be in UTF-8. The --ass-styles option is a fringe option anyway (and will
destroy your subtitles), so having codepage support for it isn't
important at all.
Instead of parsing the ASS file in demux_libass.c and trying to pass the
ASS_Track to the subtitle renderer, just read all file data in
demux_libass.c, and let the subtitle renderer pass the file contents to
ass_process_codec_private(). (This happens to parse full files too.)
Makes the code simpler, though it also relies harder on the (messy)
probe logic in demux_libass.c.
--ass-style-override=force now attempts to override the 'Default' style.
May or may not work. In some situations it will work, but also mess up
seemingly unrelated things like signs typeset with ASS.
Set subtitle resolution to video resolution when avctx->width and
avctx->height are zero.
This can happen with broken vobsubs that have no size set in their
.idx file (or Matroska extradata). At least with the test file provided
in issue #551, using the video resolution as fallback instead of what
guess_resolution() does is better.
Note that these files clearly are broken. It seems this particular
file was created by trying to use ffmpeg to transcode DVB subtitles
to vobsub, and ffmpeg "forgot" to set the subtitle resolution in the
destination file. On the other hand, ffmpeg DVB and PGS decoders set
the resolution on the first subtitle packet (or somewhere close), so
it's not really clear what to do here.
Closes#551.
Signed-off-by: wm4 <wm4@nowhere>
Patch by xylosper, rewritten commit message by wm4.
The mplayer decoder (spudec.c) actually handled this. There was explicit
code for binary palettes (16 32 bit values), and the subtitle resolution
was handled by video resolution coincidentally matching the subtitle
resolution.
Whoever puts vobsub into mp4 should be punished.
Fixes the sample gundam_sample.mp4, closes github issue #547.
Not everything in the OSD path handles 0x0 sized sub-bitmaps well. At
least the code implementing --sub-gray had severe problems with it.
Fix this by skipping such bitmaps.
If, for some reason, the subtitle renderer attempts to render a
subtitle before SD_CTRL_SET_VIDEO_PARAMS was called, it passed a
value calculated from invalid values. This can happen with --vf=sub
and --start. The crash happens if 1. there was a subtitle packet that
falls into the timestamp of the rendered video frame, 2. the playloop
hasn't informed the subtitle decoder about the video resolution yet
(normally unneeded, because that is used for weird corner cases only,
so this code is a bit fuzzy), and 3. something actually requests a
frame to be drawn from the subtitle renderer, like with vf_sub.
The actual crash was due to passing NaN as pixel aspect to libass,
which then created glyphs with ridiculous sizes, involving a few
integer overflows and unchecked mallocs.
The sd_lavc.c and sd_spu.c cases probably don't crash, but I'm not
sure, and it's better fix them anyway.
Not bothering with sd_spu.c, this crap is for compatibility and will
be removed soon.
Note that this would have been no problem, had the code checked whether
SD_CTRL_SET_VIDEO_PARAMS was actually called. This commit adds such a
check (although it basically checks after using the parameters).
Regression since 49caa0a7 and 633fde4a.
vo->aspdat is basically an outdated version of vo->params, plus some
weirdness. Get rid of it, which will allow further cleanups and which
will make multithreading easier (less state to care about).
Also, simplify some VO code by using mp_image_set_attributes() instead
of caring about display size, colorspace, etc. manually. Add the
function osd_res_from_image_params(), which is often needed in the case
OSD renders into an image.
Do two things:
1. add locking to struct osd_state
2. make struct osd_state opaque
While 1. is somewhat simple, 2. is quite horrible. Lots of code accesses
lots of osd_state (and osd_object) members. To make sure everything is
accessed synchronously, I prefer making osd_state opaque, even if it
means adding pretty dumb accessors.
All of this is meant to allow running VO in their own threads.
Eventually, VOs will request OSD on their own, which means osd_state
will be accessed from foreign threads.
The plan is to make the whole OSD thread-safe, and we start with this.
We just put locks on all entry points (fortunately, dec_sub.c and all
sd_*.c decoders are very closed off, and only the entry points in
dec_sub.h let you access it). I think this is pretty ugly, but at least
it's very simple.
There's a special case with sub_get_bitmaps(): this function returns
pointers to decoder data (specifically, libass images). There's no way
to synchronize this internally, so expose sub_lock/sub_unlock functions.
To make things simpler, and especially because the lock is sort-of
exposed to the outside world, make the locks recursive. Although the
only case where this is actually needed (although trivial) is
sub_set_extradata().
One corner case are ASS subtitles: for some reason, we keep a single
ASS_Renderer instance for subtitles around (probably to avoid rescanning
fonts with ordered chapters), and this ASS_Renderer instance is not
synchronized. Also, demux_libass.c loads ASS_Track objects, which are
directly passed to sd_ass.c. These things are not synchronized (and
would be hard to synchronize), and basically we're out of luck. But I
think for now, accesses happen reasonably serialized, so there is no
actual problem yet, even if we start to access OSD from other threads.
Subtitle formats with frame based timing require using the video FPS to
compute proper subtitle timestamps. But it looks like the calculation to
do that was inversed.
Note that we don't try to be clever about detecting the files as
subtitles: we just check the file extension. We could go all the way and
check the files by opening them with a demuxer, but that would probably
do more bad than good.
This is relatively hacky, but it's Christmas, so it's ok. This does two
things: 1. allow selecting two subtitle tracks, and 2. include a hack
that renders the second subtitle always as toptitle. See manpage
additions how to use this.
There's a single mp_msg() in path.c, but all path lookup functions seem
to depend on it, so we get a rat-tail of stuff we have to change. This
is probably a good thing though, because we can have the path lookup
functions also access options, so we could allow overriding the default
config path, or ignore the MPV_HOME environment variable, and such
things.
Also take the chance to consistently add talloc_ctx parameters to the
path lookup functions.
Also, this change causes a big mess on configfiles.c. It's the same
issue: everything suddenly needs a (different) context argument. Make it
less wild by providing a mp_load_auto_profiles() function, which
isolates most of it to configfiles.c.
In my opinion, config.h inclusions should be kept to a minimum. MPlayer
code really liked including config.h everywhere, though, even in often
used header files. Try to reduce this.
Since m_option.h and options.h are extremely often included, a lot of
files have to be changed.
Moving path.c/h to options/ is a bit questionable, but since this is
mainly about access to config files (which are also handled in
options/), it's probably ok.
The tmsg stuff was for the internal gettext() based translation system,
which nobody ever attempted to use and thus was removed. mp_gtext() and
set_osd_tmsg() were also for this.
mp_dbg was once enabled in debug mode only, but since we have log level
for enabling debug messages, it seems utterly useless.
The OSD style settings depend on the PlayRes, simply because all style
values are implicitly scaled by the PlayResY in libass. Also, the OSC
changes the PlayResY in certain situations, so something could go wrong.
But not sure if this actually matters in practice.
This simplifies things, although it is slightly less efficient (probably
uses a bit more memory).
This also happens to fix that the OSC dropped the libass cache on every
frame.
This doesn't have much value. It can't be accessed by anything else than
the actual subtitle renderer (sd_ass.c). sd_ass.c could create the
renderer itself, except that we apparently want to save memory (and some
font loading time) when using ordered chapters or multiple subtitle
tracks.
This readds a more or less completely new dvdnav implementation, though
it's based on the code from before commit 41fbcee. Note that this is
rather basic, and might be broken or not quite usable in many cases.
Most importantly, navigation highlights are not correctly implemented.
This would require changes in the FFmpeg dvdsub decoder (to apply a
different internal CLUT), so supporting it is not really possible right
now. And in fact, I don't think I ever want to support it, because it's
a very small gain for a lot of work. Instead, mpv will display fake
highlights, which are an approximate bounding box around the real
highlights.
Some things like mouse input or switching audio/subtitles stream using
the dvdnav VM are not supported.
Might be quite fragile on transitions: if dvdnav initiates a transition,
and doesn't give us enough mpeg data to initialize video playback, the
player will just quit.
This is added only because some users seem to want it. I don't intend to
make mpv a good DVD player, so the very basic minimum will have to do.
How about you just convert your DVD to proper video files?
If the timebase is set, it's used for converting the packet timestamps.
Otherwise, the previous method of reinterpret-casting the mpv style
double timestamps to libavcodec style int64_t timestamps is used.
Also replace the kind of awkward mp_get_av_frame_pkt_ts() function by
mp_pts_from_av(), which simply converts timestamps in a way the old
function did. (Plus it takes a timebase parameter, similar to the
addition to mp_set_av_packet().)
Note that this should not change anything yet. The code in ad_lavc.c and
vd_lavc.c passes NULL for the timebase parameters. We could set
AVCodecContext.pkt_timebase and use that if we want to give libavcodec
"proper" timestamps.
This could be important for ad_lavc.c: some codecs (opus, probably mp3
and aac too) have weird requirements about doing decoding preroll on the
container level, and thus require adjusting the audio start timestamps
in some cases. libavcodec doesn't tell us how much was skipped, so we
either get shifted timestamps (by the length of the skipped data), or we
give it proper timestamps. (Note: libavcodec interprets or changes
timestamps only if pkt_timebase is set, which by default it is not.)
This would require selecting a timebase though, so I feel uncomfortable
with the idea. At least this change paves the way, and will allow some
testing.
This is not needed anymore, because we decided that the PAR of the
decoded video matters, and not the PAR of the filtered video that
arrives at the VO.
Use sh_stream over sh_sub. Use dec_sub (and mpctx->d_sub) instead of the
stream header. This aligns the subtitle code with the recent audio and
video refactoring.
sh_sub still has the decoder context, though. This is because we want to
avoid reinit when switching segments with ordered chapters. (Reinit is
fast, except for creating the ASS_Renderer, which in turn triggers
fontconfig.) Not sure how much this matters, though, because the initial
segment switch will lazily initialize the decoder anyway.
We found that the stretching - although it usually improves the looks of
the fonts - is incorrect.
On DVD, subtitles can cover the full area of the picture, and they have
the same pixel aspect as the movie itself.
Too bad many commercially released DVDs use bitmap fonts made with the
wrong pixel aspect (i.e. assuming 1:1) - --stretch-dvd-subs will make
these more pretty then.
The previous code used the output video's pixel aspect for stretching
purposes, breaking rendering with e.g. -vf scale in the chain. Now
subtitles are stretched using the input video's pixel aspect only,
matching the intentions of the original subtitle author.
The configure followed 5 different convetions of defines because the next guy
always wanted to introduce a new better way to uniform it[1]. For an
hypothetic feature 'hurr' you could have had:
* #define HAVE_HURR 1 / #undef HAVE_DURR
* #define HAVE_HURR / #undef HAVE_DURR
* #define CONFIG_HURR 1 / #undef CONFIG_DURR
* #define HAVE_HURR 1 / #define HAVE_DURR 0
* #define CONFIG_HURR 1 / #define CONFIG_DURR 0
All is now uniform and uses:
* #define HAVE_HURR 1
* #define HAVE_DURR 0
We like definining to 0 as opposed to `undef` bcause it can help spot typos
and is very helpful when doing big reorganizations in the code.
[1]: http://xkcd.com/927/ related
DVD subs (rarely) have subtitle events without end timestamp. The
duration is unknown, and they should be displayed until they're
replaced by the next event.
FFmpeg fails hard to make us aware whether duration is unknown or
actually 0, so we can't distinguish between these two cases. It fails
at this twice: AVPacket.duration is set to 0 if duration is unknown,
and AVSubtitle.end_display_time has the same issue.
Add a hack that considers all bitmap subtitles with duration==0 as
events with uknown length. I'd rather accidentally display a hidden
subtitle (if they exist at all), instead of not displaying random
subtitles at all.
See github issue #325.
First, don't try to seek if the result is 0 (i.e. nothing found, or
subtitle event happens to be exactly on spot).
Second, since we never can make sure that we actually seek to the exact
subtitle PTS (seeking "snaps" to video PTS), offset the seek by 10ms.
Since most subtitle events are longer than 10ms, this should work fine.
This is pretty much a hack for the OSC. It will allow it to rely on a
somewhat predictable style, instead of having to overwrite all user
OSD settings manually with override tags.
This is preliminary. There are still tons of issues, and any aspect
of scripting may change in the future. I decided to merge this
(preliminary) work now because it makes it easier to develop it, not
because it's done. lua.rst is clear enough about it (plus some
sarcasm).
This requires linking to Lua. Lua has no official pkg-config file, but
there are distribution specific .pc files, all with different names.
Adding a non-pkg-config based configure test was considered, but we'd
rather not.
One major complication is that libquvi links against Lua too, and if
the Lua version is different from mpv's, you will get a crash as soon
as libquvi uses Lua. (libquvi by design always runs when a file is
opened.) I would consider this the problem of distros and whoever
builds mpv, but to make things easier for users, we add a terrible
runtime test to the configure script, which probes whether libquvi
will crash. This is disabled when cross-compiling, but in that case
we hope the user knows what he is doing.
This code was made inactive some months ago. At this time it wasn't
entirely clear whether this code was still needed, but now I'm pretty
sure it isn't. Even if it is, it didn't work anymore.
Cherry picked from various commits in lua_experiment by ChrisK2.
The metrics of the OSD symbols change slightly, possibly due to the
font editor that was used, and the metrics were not correct to begin
with. (But the real reason seems unknown.) Remove the rescaling of
the OSD font in ASS_USE_OSD_FONT, because the height more or less fits
now. (This change wasn't in the lua_experiment branch.)
Even if a subtitle was explicitly loaded with -sub, it was still auto-
loaded (if auto-loading applied to that file). Fix this by explicitly
checking whether a file is already loaded.
The check is maximal naive and just compares the filenames as strings.
The change in find_subfiles.c is so that "-sub something.ass" happens to
work (auto-loading prepended a "./" to it, so the naive filename
comparison check didn't work).
External vobsubs usually come as .idx/.sub pairs. Loading the .idx file
implicitly loads the .sub file, whereas loading the .sub file will kind
of work, but miss important information such as subtitle resolution. Or
in other words, if the .idx file exists, adding the .sub file as track
is useless and confusing.
Explicitly remove .sub file from the auto-load suntitle list in these
cases. Standalone .sub files are still loaded.
We also drop that weird logic that excluded .utf8 files from being
loaded if -subcp was in use. I hope the associated use case didn't make
much sense to begin with. If not, we could still implement it properly,
instead of this weird hack.
Use mp_path_exists() to check for existence of a file (which in turn
uses stat()), instead of opening and closing it. The difference is that
if we don't have sufficient permissions to read the subtitle files, we
will loudly complain. Personally, I prefer this behavior.
The way this was added to FFmpeg is less than ideal, because it requires
text parsing in the Matroska demuxer. But in order to use the FFmpeg
webvtt-to-ass converter, we still have to mimic this in some way. We do
this by putting the parsing into sd_lavc_conv.c, before the subtitle
packet is passed to libavcodec. At least this keeps the ugliness out of
unrelated code.
There is some change that FFmpeg will fix their design eventually.
Instead of rewriting the parsing code, we simply borrow it from FFmpeg's
Matroska demuxer.
Not actually useful. This would break whenever a new text subtitle
format would be added, which requires a binary->text transformation.
(mov_text is one such format; disable it.) In general, we would have
to know which packet formats are binary, which we don't, so the only
reasonable way to handle this is a white list.
Broken UTF-8 in this context means we treat it as UTF-8, but we also
interpret broken UTF-8 sequences as Latin1.
Also, run our own UTF-8 check function before the charset detectors.
This prevents from ENCA's UTF-8 check possibly messing up (like
detecting 7-bit clean UTF-8 as ASCII, or other things). It also takes
care of UTF-8 detection if no charset detector (ENCA, libguess) is
compiled in, and it lets us deal better with cut-off UTF-8 sequences.
The fix_overlaps_and_gaps() function in dec_sub.c fixes small gaps or
overlaps between subtitle events. However, sometimes it could happen
that the corrected subtitle events could overlap by 1ms due to bad
rounding, making libass shift subtitles to reduce collisions. (The
second subtitle will be shown above the previous one, even if both
subtitles are visible only for 1ms.)
sd_ass.c rounds the timestamps when converting to integers for unknown
reasons. I think it would work fine without that rounding, but since
I have no clue why it rounds, and since it could be needed to ensure
correct timestamps with ASS subtitles demuxed from Matroska, I'd rather
not touch it. So the solution is to use already rounded timestamps to
calculate the new subtitle duration in fix_overlaps_and_gaps().
See github issue #182.
This reverts commit 689a25003f, with some
adjustments to code that was added after that commit.
I just messed up big time. We don't need this, and in fact the commit
confused straight and premultiplied alpha at one point (just a simple
inverted condition due to an oversight), which is why it looked like
it was working.
In commit 2827295 I wrote:
Also, libva can't decide whether it accepts straight or premultiplied
alpha for OSD sub-pictures [...]
That was just me messing up and being severely confused by my own bugs.
VA API uses premultiplied alpha, which by the way is nice and
thoughtful of the VA API devs.
Well, this was stupid. But in the end, I'm glad that I could actually
reduce codesize by a good amount again.
This is for VAAPI support. VAAPI does not support premultiplied alpha
for OSD. (Normally, we prefer premultiplied, because it has better
behavior on scaling.)
I'm not sure whether blending in the ASS->RGBA part is correct and I
didn't test it extensively.
In general, this warning can hint to actual bugs. We don't enable it
yet, because it would conflict with some unmerged code, and we should
check with clang too (this commit was done by testing with gcc).
I'm not sure what's correct: stretching the DVD subtitles from storage
aspect ratio to video display aspect ratio, or displaying subtitles
using 1:1 PAR. Until now, DVD subtitles (as well as all other bitmap
subtitles) were always stretched to the video. There are good arguments
why this would be the correct behavior: DVDs were made for playback on
TV, which display anamorphic video by adjusting the horizontal refresh
rate, and thus wouldn't even be capable of DVD subtitles with square PAR
(other than resampling the subtitles additionally).
However, I haven't seen a sample yet where subtitles do _not_ look
stretched using this method. Rendering them at 1:1 PAR looks better.
Technically, we render them at display PAR (and not 1:1 PAR). Do this in
a way so that the subtitle area is always inside of the video frame if
display and video aspect ratios mismatch.
For DVB subtitles, the old method looks more correct, so this is special
cased to DVD subtitles.
I might revert this commit if it turns out that it's an disimprovement.
Partial packet reads were needed because the video/audio parsers were
working on top of them. So it could happen that a parser read a part of
a packet, and returned that to the decoder. With libavformat/libavcodec,
packets are already parsed, and everything is much simpler.
Most of the simplifications in ad_spdif could have been done earlier.
Remove some other stuff as well, like the questionable slave mode start
time reporting (could be replaced by proper code, but we don't bother).
Remove the unused skip_audio_frame() functionality as well (it was used
by old demuxers). Some functions become private to demux.c, like
demux_fill_buffer(). Introduce new packet read functions, which have
simpler semantics. Packets returned from them are owned by the caller,
and all packets in the demux.c packet queue are considered unread.
Remove special code that dropped subtitle packets with size 0. This
used to be needed because it caused special cases in the old code.
Delete demux_avi, demux_asf, demux_mpg, demux_ts. libavformat does
better than them (except in rare corner cases), and the demuxers have
a bad influence on the rest of the code. Often they don't output
proper packets, and require additional audio and video parsing. Most
work only in --no-correct-pts mode.
Remove them to facilitate further cleanups.
This means the direct libass usage can be removed from command.c, and no
weird hacks for retrieving the ASS_Track are needed.
Also fix a bug when using this feature with ordered chapters.
This was changed as part of commit b44202b as an intended
simplification, but it's actually nicer to have the subtitles
update immediately even if paused.
Should we actually get into trouble for unproper handling of
frame-based subtitle formats, this might be the simplest way to
work this around. Also is a bit more intuitive than -subfps, which
might use an unknown, misdetected, or non-sense video FPS.
Still pretty silly, though.
Before this commit, SRT demuxing and display actually happened to work
on Libav. But it was using the libavcodec srt converter (which is
essentially unmaintained in Libav), and timing postprocessing didn't
work. For some background explanations see sd_lavf_srt.c.
Until now, timing and charset recoding postprocessing was applied on
packets as they were output by the demuxer, and then passed to the
decoders. Make it so that postprocessing can happen after some decoders
in special situations.
This code was once part of subreader.c, then traveled to libass, and now
made its way back to the fork of the fork of the original code, MPlayer.
It works pretty much the same as subreader.c, except that we have to
concatenate some packets to do auto-detection. This is rather annoying,
but for all we know the actual source file could be a binary format.
Unlike subreader.c, the iconv context is reopened on each packet. This
is simpler, and with respect to multibyte encodings, more robust.
Reopening is probably not a very fast, but I suspect subtitle charset
conversion is not an operation that happens often or has to be fast.
Also, this auto-detection is disabled for microdvd - this is the only
format we know that has binary data in its packets, but is actually
decoded to text. FFmpeg doesn't really allow us to solve this properly,
because a) the input packets can be binary, and b) the output will be
checked whether it's UTF-8, and if it's not, the output is thrown away
and an error message is printed. We could just recode the decoded
subtitles before sd_ass if it weren't for that.
demux_libass.c allows us to make subtitle format detection part of the
normal file loading process. libass has no probe function, but trying to
load the start of a file (the first 4 KB) is good enough. Hope that
libass can even handle random binary input gracefully without printing
stupid log messages, and that the libass parser doesn't accept too many
non-ASS files as input.
This doesn't handle the -subcp option correctly yet. This will be fixed
later.
subreader.c (before this commit renamed to demux_subreader.c) was
special cased to the -sub option. The plan is using the normal demuxer
codepath for all subtitle formats (so we can prefer libavformat demuxers
for most formats).
There are some subtle changes. The probe size is restricted to 32 KB
(instead of unlimitted + giving up after 100 lines of input). For
formats like MicroDVD, the video FPS isn't used anymore, because it's
not available on the subtitle demuxer level. Instead, hardcode it to
23.976 FPS (libavformat seems to do the same). The user can probably
still use -sub-fps to fix the timing. Checking the file extension for
".utf"/".utf8"/".utf-8" is simply removed (seems worthless, was in the
way, and I've never seen this anywhere).
Actually check the newly added text for whitespace, and not the
uninitialized buffer after it. Also, if an even is only whitespace,
don't add it at all.
sd_ass contains some code that treats subtitle events with duration 0
specially, and adjust their duration so that they will disappear with
the next event.
This is most likely not needed anymore. Some subtitle formats allow
omitting the duration so that the event is visible until the next one,
but both subreader.c as well as libavformat subtitle demuxers already
handle this.
Subtitles embedded in mp4 files (movtext) used to trigger this code. But
these files appear to export subtitle duration correctly (at least
libavcodec's movtext decoder is using this assumption). Since commit
6dbedd2 changed demux_lavf to actually copy the packet duration field,
the code removed with this commit isn't needed anymore for correct
display of movtext subtitles. (The change in sd_movtext is for dropping
empty subtitle events, which would now be "displayed" - libavcodec does
the same.)
On the other hand, this code incorrectly displayed hidden events in .srt
subtitles. See for example the first event in SubRip_capability_tester.srt
(part of FFmpeg's FATE). These intentionally have a duration of 0, and
should not be displayed. (As of with this commit, they are still
displayed in external .srt subs because of subreader.c hacks.)
However, we can't be 100% sure that this code is really unneeded, so
just comment the code. Hopefully it can be removed if there are no
regressions after some weeks or months.
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.)
