Simple enough to do. May have mixed results. Typically, bitmap subtitles
will have a tight bounding box around the rendered text. But if for
example there is text on the top and bottom, it may be a single big
bitmap with a large transparent area between top and bottom. In
particular, DVD subtitles are really just a single screen-sized
RLE-encoded bitmap, though libavcodec will crop off transparent areas.
Like with sd_ass, you can't move subtitles _down_ if they are already in
their origin position. This could probably be improved, but I don't want
to deal with that right now.
See manpage additions. This is a huge hack. You can bet there are shit
tons of bugs. It's literally forcing square pegs into round holes.
Hopefully, the manpage wall of text makes it clear enough that the whole
shit can easily crash and burn. (Although it shouldn't literally crash.
That would be a bug. It possibly _could_ start a fire by entering some
sort of endless loop, not a literal one, just something where it tries
to do work without making progress.)
(Some obvious bugs I simply ignored for this initial version, but
there's a number of potential bugs I can't even imagine. Normal playback
should remain completely unaffected, though.)
How this works is also described in the manpage. Basically, we demux in
reverse, then we decode in reverse, then we render in reverse.
The decoding part is the simplest: just reorder the decoder output. This
weirdly integrates with the timeline/ordered chapter code, which also
has special requirements on feeding the packets to the decoder in a
non-straightforward way (it doesn't conflict, although a bugmessmass
breaks correct slicing of segments, so EDL/ordered chapter playback is
broken in backward direction).
Backward demuxing is pretty involved. In theory, it could be much
easier: simply iterating the usual demuxer output backward. But this
just doesn't fit into our code, so there's a cthulhu nightmare of shit.
To be specific, each stream (audio, video) is reversed separately. At
least this means we can do backward playback within cached content (for
example, you could play backwards in a live stream; on that note, it
disables prefetching, which would lead to losing new live video, but
this could be avoided).
The fuckmess also meant that I didn't bother trying to support
subtitles. Subtitles are a problem because they're "sparse" streams.
They need to be "passively" demuxed: you don't try to read a subtitle
packet, you demux audio and video, and then look whether there was a
subtitle packet. This means to get subtitles for a time range, you need
to know that you demuxed video and audio over this range, which becomes
pretty messy when you demux audio and video backwards separately.
Backward display is the most weird (and potentially buggy) part. To
avoid that we need to touch a LOT of timing code, we negate all
timestamps. The basic idea is that due to the navigation, all
comparisons and subtractions of timestamps keep working, and you don't
need to touch every single of them to "reverse" them.
E.g.:
bool before = pts_a < pts_b;
would need to be:
bool before = forward
? pts_a < pts_b
: pts_a > pts_b;
or:
bool before = pts_a * dir < pts_b * dir;
or if you, as it's implemented now, just do this after decoding:
pts_a *= dir;
pts_b *= dir;
and then in the normal timing/renderer code:
bool before = pts_a < pts_b;
Consequently, we don't need many changes in the latter code. But some
assumptions inhererently true for forward playback may have been broken
anyway. What is mainly needed is fixing places where values are passed
between positive and negative "domains". For example, seeking and
timestamp user display always uses positive timestamps. The main mess is
that it's not obvious which domain a given variable should or does use.
Well, in my tests with a single file, it suddenly started to work when I
did this. I'm honestly surprised that it did, and that I didn't have to
change a single line in the timing code past decoder (just something
minor to make external/cached text subtitles display). I committed it
immediately while avoiding thinking about it. But there really likely
are subtle problems of all sorts.
As far as I'm aware, gstreamer also supports backward playback. When I
looked at this years ago, I couldn't find a way to actually try this,
and I didn't revisit it now. Back then I also read talk slides from the
person who implemented it, and I'm not sure if and which ideas I might
have taken from it. It's possible that the timestamp reversal is
inspired by it, but I didn't check. (I think it claimed that it could
avoid large changes by changing a sign?)
VapourSynth has some sort of reverse function, which provides a backward
view on a video. The function itself is trivial to implement, as
VapourSynth aims to provide random access to video by frame numbers (so
you just request decreasing frame numbers). From what I remember, it
wasn't exactly fluid, but it worked. It's implemented by creating an
index, and seeking to the target on demand, and a bunch of caching. mpv
could use it, but it would either require using VapourSynth as demuxer
and decoder for everything, or replacing the current file every time
something is supposed to be played backwards.
FFmpeg's libavfilter has reversal filters for audio and video. These
require buffering the entire media data of the file, and don't really
fit into mpv's architecture. It could be used by playing a libavfilter
graph that also demuxes, but that's like VapourSynth but worse.
There are 3 packet reading functions in the demux API, which all
function completely differently. One of them, demux_read_packet(), has
only 1 caller, which is in dec_sub.c. Change this caller to use
demux_read_packet_async() instead. Since it really wants to do a
blocking call, setup some proper waiting. This uses mp_dispatch_queue,
because even though it's overkill, it needs the least code.
In practice, waiting actually never happens. This code is only called on
code paths where everything is already read into memory (libavformat's
subtitle demuxers simply behave this way). It's still a bit of a
"coincidence", so implement it properly anyway.
If suubtitle decoder init fails, we still need to unset the demuxer
wakeup callback. Add a sub_destroy() call to the failure path. This also
happens to fix a missed pthread_mutex_destroy() call (in practice this
was a nop, or a memory leak on BSDs).
UB-sanitizer complains that we shift bits into the sign (when a is
used). Change it to unsigned, which in theory is more correct and
silences the warning.
Doesn't matter in practice, both the "bug" and the fix have 0 impact.
It would always autodetect it based on the passed style block,
but as we are defining it - we might as well define it always.
(As far as I can see all decoders in libavcodec utilize 4+ style
blocks)
Manual changes done:
* Merged the interface-changes under the already master'd changes.
* Moved the hwdec-related option changes to video/decode/vd_lavc.c.
Only printable ASCII characters were considered to be valid texts. Make
it possible that UTF-8 contents are also considered valid.
This does not make the SDH subtitle filter support non-English
languages. This just prevents the filter from blindly marking lines that
have only UTF-8 characters as empty.
Fixes#6502
libavcodec normally drops subtitle lines that fail a check for invalid
UTF-8 (their check is slightly broken too, by the way). This was always
annoying and inconvenient, but now there is a mechanism to prevent
it from doing this. Requires newst libavcodec.
Remove them from the big MPOpts struct and move them to their sub
structs. In the places where their fields are used, create a private
copy of the structs, instead of accessing the semi-deprecated global
option struct instance (mpv_global.opts) directly.
This actually makes accessing these options finally thread-safe. They
weren't even if they should have for years. (Including some potential
for undefined behavior when e.g. the OSD font was changed at runtime.)
This is mostly transparent. All options get moved around, but most users
of the options just need to access a different struct (changing sd.opts
to a different type changes a lot of uses, for example).
One thing which has to be considered and could cause potential
regressions is that the new option copies must be explicitly updated.
sub_update_opts() takes care of this for example.
Another thing is that writing to the option structs manually won't work,
because the changes won't be propagated to other copies. Apparently the
only affected case is the implementation of the sub-step command, which
tries to change sub_delay. Handle this one explicitly (osd_changed()
doesn't need to be called anymore, because changing the option triggers
UPDATE_OSD, and updates the OSD as a consequence). The way the option
value is propagated is rather hacky, but for now this will do.
It was split at least across osd.c and sd_ass.c/sd_lavc.c. sd_lavc.c
actually ignored most of the more obscure subtitle timing things.
There's no reason for this - just move it all to dec_sub.c (mostly from
sd_ass.c, because it has some of the most complex stuff).
Now timestamps are transformed as they enter or leave dec_sub.c.
There appear to have been some subtle mismatches about how subtitle
timestamps were transformed, e.g. sd_functions.accepts_packet didn't
apply the subtitle speed to the timestamp. This patch should fix them,
although it's not clear if they caused actual misbehavior.
The semantics of SD_CTRL_SUB_STEP are slightly changed, which is the
reason for the changes in command.c and sd_lavc.c.
I've decided that MP_TRACE means “noisy spam per frame”, whereas
MP_DBG just means “more verbose debugging messages than MSGL_V”.
Basically, MSGL_DBG shouldn't create spam per frame like it currently
does, and MSGL_V should make sense to the end-user and provide mostly
additional informational output.
MP_DBG is basically what I want to make the new default for --log-file,
so the cut-off point for MP_DBG is if we probably want to know if for
debugging purposes but the user most likely doesn't care about on the
terminal.
Also, the debug callbacks for libass and ffmpeg got bumped in their
verbosity levels slightly, because being external components they're a
bit less relevant to mpv debugging, and a bit too over-eager in what
they consider to be relevant information.
I exclusively used the "try it on my machine and remove messages from
MSGL_* until it does what I want it to" approach of refactoring, so
YMMV.
The OpenType Font File specification recommends that "Collection fonts
that use CFF or CFF2 outlines should have an .OTC extension." mpv
should accept .otc as a fallback extension for font detection should
the mimetype detection fail.
IETF RFC8081 added the "font" top-level media type,
including font/ttf, font/otf, font/sfnt, and also
font/collection. These font formats are all supported
by mpv/libass but they are not accepted as valid
Matroska mime types. mpv can load them via file extension
and they work as expected, so files using the new types
should not trigger a warning from mpv.
The current invocation of bstr_cut is as good as no cutting at all.
Almost the entire header is reread in every iteration of the loop.
I don't know how many styles libavcodec tends to generate, but if
(now or in the future) it generates many, then this loop is slow
for no good reason. If anything, the code would be more clear and
have the same performance if it didn't call bstr_cut at all.
The intention here (and the sensible thing regardless) seems to be
to skip the part of the string that bstr_find has already looked
through and found nothing. This commit additionally skips the whole
substring, because overlapping matches are impossible.
In some cases, demux_mkv will detect a start time slightly above 0, but
there might still be a subtitle starting at exactly 0. When the player
rebases the timestamps to assumed start time, the subtitle will have a
slightly negative timestamp in the end. libavcodec's subtitle converter
turns this into a larger number due to underflow. Fix by clamping
subtitles always to 0, which may or may not be what you want.
At least it fixes#5047.
The new_segment field was used to track the decoder data flow handler of
timeline boundaries, which are used for ordered chapters etc. (anything
that sets demuxer_desc.load_timeline). This broke seeking with the
demuxer cache enabled. The demuxer is expected to set the new_segment
field after every seek or segment boundary switch, so the cached packets
basically contained incorrect values for this, and the decoders were not
initialized correctly.
Fix this by getting rid of the flag completely. Let the decoders instead
compare the segment information by content, which is hopefully enough.
(In theory, two segments with same information could perhaps appear in
broken-ish corner cases, or in an attempt to simulate looping, and such.
I preferred the simple solution over others, such as generating unique
and stable segment IDs.)
We still add a "segmented" field to make it explicit whether segments
are used, instead of doing something silly like testing arbitrary other
segment fields for validity.
Cached seeking with timeline stuff is still slightly broken even with
this commit: the seek logic is not aware of the overlap that segments
can have, and the timestamp clamping that needs to be performed in
theory to account for the fact that a packet might contain a frame that
is always clipped off by segment handling. This can be fixed later.
If a VO-area option changes, gl_video_resize() is called
unconditionally. This function does something even if the size does not
change (at least it discards buffered frames for interpolation), which
can lead to stutter when you keep firing option change events during
playback.
Check for an actual resize, and if nothing changes, exit early.
Lua scripts can call osd_set_external() early (before the VO window is
created and obj->vo_res is filled), in which case the PlayResX field
would be set to nonsense, and libass would print a pointless warning.
There's an easy and a hard fix: either just go on and pass dummy values
to libass (basically like before, just clamp them to avoid the values
which make libass print the warning). Or attempt to update the PlayRes
field to correct values on rendering (since at rendering time, you
always know the screen size and the correct values). Do the latter.
Since various things use PlayRes for scaling things, this might still
not be fully ideal. This is a general problem with the async scripting
interface.
This API isn't deprecated (yet?), but it's still inferior and harder to
use than avcodec_free_context().
Leave the call only in 1 case in af_lavcac3enc.c, where we apparently
seriously close and reopen the encoder for whatever reason.
List of changes:
1. Rename `signfs` to `scale`, to better match what it actually does
(force --sub-scale to apply to ASS subtitles), and fix the blatantly
wrong documentation (it actually specifically does *not* apply to
signs)
2. Rename `--sub-ass-style-override` to `--sub-ass-override` to help
reduce confusion between it and `--sub-ass-force-style`, as well as
pointing out that it doesn't necessarily actually override styles.
(The new `scale` option, for example, only sets
ASS_OVERRIDE_BIT_FONT_SIZE, but not ASS_OVERRIDE_BIT_STYLE)
3. Mention that `--sub-ass-override` is generally sort of smart about
only overriding dialog, not signs.
All contributors of the code used for these files agreed to the LGPL
relicensing.
There are some unaccounted contributors, but all of their code was
completely removed before. (The only exception is one contributor whose
only line left was "#include <string.h>". I don't know if that's
copyrightable, but it wasn't needed anyway, so just remove it.)
These files started out as libvo/sub.* (renamed to sub/sub.*, then
renamed again to sub/osd.*). They used to contain code for rendering
the OSD (as in, actual pixel manipulation and text layouting). But
later all this code was dropped, and libass was used to render the OSD
instead. Actual subtitle rendering was reimplemented in other files
(the old subtitle rendering path is completely gone).
One potential problem are the option declarations, which makes this
harder, as these options involve more history. But it turns out most of
them were reimplemented since 80270218cb, rather than taken from old
code. (Although not all - but the rest covered by relicensing
agreements.)
This also affects osd_state.h, which was apparently incorrectly implied
to be LGPL.
All contributors have agreed.
Compared to sd_ass.c, this has a pretty simple history:
av_sub.c -> sub/av_sub.c -> sub/sd_lavc.c
At one point, some code from spudec.c was added to it, but it was
removed again later.
All contributors of the code used for sd_ass.c agreed to the LGPL
relicensing. Some code has a very chaotic history, due to MPlayer
subtitle handling being awful, chaotic, and having been refactored a
dozen of times. Most of the subtitle code was actually rewritten from
scratch (a few times), and the initial sd_ass.c was pretty tiny. So we
should be fine, but it's still a good idea to look at this closely.
Potentially problematic cases of old code leaking into sd_ass.c are
mentioned below.
Some code originates from demux_mkv. Most of this was added by eugeni,
and later moved into mplayer.c or mpcommon.c. The old demux_mkv ASS/SSA
subtitle code is somewhat dangerous from a legal perspective, because it
involves 2 patches by a certain Tristan/z80, who disagreed with LGPL,
and who told us to "rewrite" parts we need. These patches were for
converting the ASS packet data to the old MPlayer text subtitle data
structures. None of that survived in the current code base.
Moving the subtitle handling out of demux_mkv happened in the following
commits: bdb6a07d2a, de73d4dd97, 61e4a80191. The code by
z80 was removed in b44202b69f.
At this time, the z80 code was located in mplayer.c and subreader.c.
The code was fully removed, being unnecessary due to the entire old
subtitle rendering code being removed. This adds a ass_to_plaintext(),
function, which replaces the old ASS tag stripping code in
sub_add_text(), which was based on the z80 code. The new function was
intended to strip ASS tags in a correct way, instead of somehow
dealing with other subtitle types (like HTML-style SRT tags), so it
was written from scratch.
Another potential issue is the --sub-fix-timing option is based on
-overlapsub added in d459e64463. But the implementation is new, and
no code from that commit is used in sd_ass.c. The new implementation
started out in 64b1374a44. (The following commit, bd45eb468c
removes the original code that was replaced.) The code was later
moved into sd_ass.c.
The --sub-fps option has a similar history.
Somewhat chaostic history: libass/ass_mp.* -> ass_mp.* -> sub/ass_mp.*
As far as I can tell, everyone who ever touched these files has agreed
to the relicensing.
When the format of the subtitle bitmaps changes, such as with taking
screenshots with vo_vaapi (RGBA for the VO vs. Y8 for screenshots), the
cache image obviously needs to be recreated.
Fixes#4325.
When doing harder filtering not require a space after : results
in lines with a clock (like 10:05) to be taken as a speaker label.
So require a space after : even when doing harder filtering as
missing space is very uncommon.
Some like to add text in parentheses in the speaker label,
like XXX (loud): or just (loud):
allow parentheses when doing harder filtering
Add subtitle filter to remove additions for deaf or hard-of-hearing
(SDH). This is for English, but may in part work for others too.
This is an ASS filter and the intention is that it can always be
enabled as it by default do not remove parts that may be normal text.
Harder filtering can be enabled with an additional option.
Signed-off-by: wm4 <wm4@nowhere>
This means the subtitles will show as "intended".
For some weird reason, --sub-ass-style-override is the option that
controls style override, which implies it's specific to ASS. While that
seems weird and doesn't always reflect reality, I don't care about that
now.
To make it easier for the eyes, multi line subtitles should
be left justified (for most languages).
This adds an option to define how subtitles are to be justified
inpendently of how they are aligned.
Also add option to enable --sub-justify to be applied on ASS subtitles.
A hacky, convoluted, half-working mess that attempts to cut off overlong
playlists.
It does so by relying on the ASS formatting rule that the font size is
specified in the virtual PlayResY resolution. This means we can
(normally) easily tell how many lines fit on the screen. On the other
hand, this does not work if the text is wrapped.
This as a kludge until a Better™ solution is available.
This core of this heuristic was once copied from MPlayer's spudec.c. I
think it was meant for the case when the resolution field was missing or
so.
I couldn't find a file for which this actually does something. On the
other hand, there are samples which actually have a smaller resolution
than 720x576, and which are broken by this old hack.
For subtitles that set no resolution (I'm not sure which codec/container
that would be), there's still the fallback on video resolution.
Just get rid of this hack. Also cleanup a bit. SD_CTRL_GET_RESOLUTION
hasn't been used since DVD menu removal. get_resolution() is left with 1
call site, and would be quite awkward to keep, so un-inline it.
The previous commit means subtitles were reinitialized on every seek
(even within a segment). This commit restores the old behavior.
To check whether the segment changed at all, we don't reset the current
start/end values. This assumes the decoder wrapper is always fed by a
stream which doesn't mix segment and non-segment packets, which is
currently always true.
If a VO is created, but no video is playing (i.e. --force-window is
used), then until now no subtitles were shown. This is because VO
subtitle display normally depends on video frame timing. If there are no
video frames, there can be no subtitles.
Change this and add some code to handle this situation specifically. Set
a subtitle PTS manually and request VO redrawing manually, which gets
the subtitles rendered somehow.
This is kind of shaky. The subtitles are essentially sampled at
arbitrary times (such as when new audio data is decoded and pushed to
the AO, or on user interaction). To make a it slightly more consistent,
force a completely arbitrary minimum FPS of 10.
Other solutions (such as creating fake video) would be more intrusive or
would require VO-level API changes.
Fixes#3684.
Rename the text subtitle options from --sub-text- to --sub-
and --ass- options to --sub-ass-.
The intention is to common sub options to prefixed --sub-
and special ASS option be seen as a special version of sub options.
The OSD options that work like the --sub- options are still named
--osd-.
Man page updated including a short note about renamed --sub-text-*
and --ass-* options to --sub-* and --sub-ass-*.
Secondary subtitle streams (to be shown on the top of the screen along
main subtitle stream) were shown with normal alignment. This is because
we tell libass to override the alignment style (a relatively recent
change, see commit 2f1eb49e). This would behave differently with old
libass versions too.
To escape the mess, just set the alignment explicitly with an override
tag instead of modifying the style.
Remove wrapper properties for OSD and video position updates, use the
new mechanism for them. We can mark the options directly. Update
behavior will work for more options (since I've casually marked more
affected options than the old less direct mechanism covered).
If --blend-subtitles=yes is given, vo_opengl will call osd_draw()
multiple times, once for subtitles, and once for OSD. This meant that
the want_redraw flag was reset before the OSD was rendered, which in
turn meant that update_osd() was never called. It seems like removing
the per-OSD object want_redraw wasn't such a good idea. Fix it by
reintroducing such a flag for OSDTYPE_OSD only.
Also, the want_redraw flag is now unused, so kill it.
Another regression caused by commit 9c9cf125. Fixes#3535.
This could in theory lead to missed updates if subtitles were switched
or external OSD overlays (via overlay-add) were updated. While the
change IDs of each of those were consistent, switching between two
separate OSD sources is not, and we have to explicitly trigger a change.
Regression since commit 9c9cf125. The new code is actually better,
because we do exactly what is needed, and don't just mess with the
update ID for libass-based OSD.
Remove the per-part force_redraw flags, and instead make the difference
between flagging dirty state and returning it to the player frontend
more explicit. The big issue is that 1. the OSD needs to know the dirty
state, and it should be cleared strictly when it is re-rendered
(force_redraw flag), and 2. the player core needs to be notified once,
and the notification must be reset (want_redraw flag).
The call in loadfile.c is replaced by making osd_set_sub() set the
change flag. Increasing the change flag on dirty state (the force_redraw
check in render_object()) should not be needed, because OSD part
renderers set it correctly (at least now).
Doing this just because someone pointed this out.
This is a bug fix, and the text alignment functionality probably got
lost sometime along the way.
For ASS subtitles, this could have unintended consequences, so it's hard
to get right - thus it's not applied to ASS subtitles.
For other text subtitles, this should be fine, though. It still works on
ASS subtitles as promised by the manpage if --no-sub-ass is used.
Whitelisting supported codecs is (probably) still better than just
allowing everything, given the weird FFmpeg API. I'm also assuming
Libav doesn't even have the codec ID, but I didn't check.
Also add a --teletext-page option, since otherwise it decodes every
teletext page and shows them in succession.
And yes, we can't use av_opt_set_int() - instead we have to set it as
string. Because FFmpeg's option system is terrible.
Like it's done for audio and video. Just to be uniform.
I'm sorry for deleting the anti-ffmpeg vitriol. It's still all true, but
since we decided to always set the timebase, the crappiness is isolated
to FFmpeg internals.
The accepts_packet packet callback is supposed to deal with subtitle
decoders which have only a small queue of current subtitle events (i.e.
sd_lavc.c), in case feeding it too many packets would discard events
that are still needed.
Normally, the number of subtitles that need to be preserved is estimated
by the rendering pts (get_bitmaps() argument). Rendering lags behind
decoding, so normally the rendering pts is smaller than the next video
frame pts, and we simply discard all subtitle events until the rendering
pts.
This breaks down in some annoying corner cases. One of them is seeking
backwards: the VO will still try to render the old PTS during seeks,
which passes a high PTS to the subtitle renderer, which in turn would
discard more subtitles than it should. There is a similar issue with
forward seeks. Add hacks to deal with those issues.
There should be a better way to deal with the essentially unknown
"rendering position", which is made worse by screenshots or rendering
with vf_sub. At the very least, we could handle seeks better, and e.g.
either force the VO not to re-render subs after seeks (ugly), or
introduce seek sequence numbers to distinguish attempts to render
earlier subtitles when a seek is done.
This has two reasons:
1. I tend to add new fields to this metadata, and every time I've done
so I've consistently forgotten to update all of the dozens of places in
which this colorimetry metadata might end up getting used. While most
usages don't really care about most of the metadata, sometimes the
intend was simply to “copy” the colorimetry metadata from one struct to
another. With this being inside a substruct, those lines of code can now
simply read a.color = b.color without having to care about added or
removed fields.
2. It makes the type definitions nicer for upcoming refactors.
In going through all of the usages, I also expanded a few where I felt
that omitting the “young” fields was a bug.
vo_vaapi is the only thing which can't scale RGBA on the GPU. (Other
cases of RGBA scaling are handled in draw_bmp.c for some reason.)
Move this code and get rid of the osd_conv_cache thing.
Functionally, nothing changes.
This affects VOs (or other code which render OSD) which does not support
the LIBASS format, but only RGBA. Instead of having a converter stage in
osd.c, make mp_ass_packer_pack() output directly in RGBA.
In general, this is work towards refcounted subtitle images.
Although we could keep the "converter" design, doing it this way seems
simpler, at least considering the current situation with only 2 OSD
formats. It also prevents copying & packing the data twice, which will
lead to better performance. (Although I guess this case is not important
at all.)
It also fixes --force-rgba-osd-rendering when used with vo_opengl,
vo_vdpau, and vo_direct3d.
The intention is to let mp_ass_packer_pack() produce different output
for the RGBA and LIBASS formats. VOs (or whatever generates the OSD)
currently do not signal a preferred format, and this mechanism just
exists to switch between RGBA and LIBASS formats correctly, preferring
LIBASS if the VO supports it.
Change all producer of libass images to packing the bitmaps into a
single larger bitmap directly when they're output. This is supposed to
help working towards refcounted sub bitmaps.
This will reduce performance for VOs like vo_xv, but not for vo_opengl.
vo_opengl simply will pick up the pre-packed sub bitmaps, and skip
packing them again. vo_xv will copy and pack the sub bitmaps
unnecessarily - but if we want sub bitmap refcounting, they'd have to be
copied anyway.
The packing code cannot be removed yet from vo_opengl, because there are
certain corner cases that still produce unpackad other sub bitmaps.
Actual refcounting will also require more work.
Since there are not many sub-rectangles, this doesn't cost too much. On
the other hand, it avoids frequent warnings with vo_xv.
Also, the second copy in mp_blur_rgba_sub_bitmap() can be dropped.
The previous few commits changed sd_lavc.c's output to packed RGB sub-
images. In particular, this means all sub-bitmaps are part of a larger,
single bitmap. Change the vo_opengl OSD code such that it can make use
of this, and upload the pre-packed image, instead of packing and copying
them again.
This complicates the upload code a bit (4 code paths due to messy PBO
handling). The plan is to make sub-bitmaps always packed, but some more
work is required to reach this point. The plan is to pack libass images
as well. Since this implies a copy, this will make it easy to refcount
the result.
(This is all targeted towards vo_opengl. Other VOs, vo_xv, vo_x11, and
vo_wayland in particular, will become less efficient. Although at least
vo_vdpau and vo_direct3d could be switched to the new method as well.)
The sub-bitmaps get extended by --sub-gauss, so we have to compute the
bounding box on the original subs. Not sure if this is really
eqauivalent to what the code did before, and I don't have the sample
anymore. (But this approach sure is a _shitty_ hack.)
Implement it directly in sd_lavc.c as well. Blurring requires extending
the size of the sub-images by the blur radius. Since we now want
sub_bitmaps to be packed into a single image, and we don't want to
repack for blurring, we add some extra padding to each sub-bitmap in the
initial packing, and then extend their size later. This relies on the
previous bitmap_packer commit, which always adds the padding in all
cases.
Since blurring is now done on parts of a large bitmap, the data pointers
can become unaligned, depending on their position. To avoid shitty
libswscale printing a dumb warning, allocate an extra image, so that the
blurring pass is done on two newly allocated images. (I don't find this
feature important enough to waste more time on it.)
The previous refactor accidentally broke this feature due to a logic bug
in osd.c. It didn't matter before it happened to break, and doesn't
matter now since the code paths are different.
Until now, subtitle renderers could export SUBBITMAP_INDEXED, which is a
8 bit per pixel with palette format. sd_lavc.c was the only renderer
doing this, and the result was converted to RGBA in every use-case
(except maybe when the subtitles were hidden.)
Change it so that sd_lavc.c converts to RGBA on its own. This simplifies
everything a bit, and the palette handling can be removed from the
common code.
This is also preparation for making subtitle images refcounted. The
"caching" in img_convert.c is a PITA in this respect, and needs to be
redone. So getting rid of some img_convert.c code is a positive side-
effect. Also related to refcounted subtitles is packing them into a
single mp_image. Fewer objects to refcount is easier, and for the libass
format the same will be done. The plan is to remove manual packing from
the VOs which need single images entirely.
Older ffmpeg releases don't have ffmpeg git commit
50401f5fb7d778583b03a13bc4440f71063d319d, which fixes ffmpeg's
pkt_timebase check to reject its default "unset" timebase as invalid.
The consequence was that all non-PGS bitmap subtitle timestamps were
forced to 0.
Of course this hit _only_ shitty distros using outdated/badly maintained
ffmpeg releases, so this is not worth working around. I've already
wasted a lot of time on analyzing this dumb issue, and it could be
useful for bisecting, so don't drop pre-3.0 ffmpeg just yet.
Fixes#3109.
libass's ass_process_chunk expects long long int for the timecode and
durations arguments, thus should use llrint instead of lrint.
This does not cause any problems on most platforms, but on cygwin, it
causes strange subtitle behaviour, like subtitles not showing, getting
stuck or old subtitles showing at the same time as new subtitles.
--sub-ass=no / --ass=no still work, but --ass-style-override=strip is
preferred now. With this change, --ass-style-override can control all
the types of style overriding.
There is an obscure feature which requires essentially reordering PTS
from different packets.
Unfortunately, libavcodec introduced a ridiculously shitty API for
this, which works very much unlike the audio/video API. Instead of
simply passing through the PTS, it wants to fuck with it for no reason,
and even worse, fucks with other fields and changes their semantivcs
(??????). This affects AVSubtitle.end_display_time. This probably will
cause issues for us, and I have no desire to find out whether it will.
Since only PGS requires this, and it happens not to use
end_display_time, do it for PGS only.
Fixes#3016.
Basically, this information is useless, because some muxers (hurr
libavformat) write bogus information anyway. This means if we e.g. see
PGS packets in mkv with duration explicitly set to 0, we must not trust
that value anyway. (The FFmpeg API problem is leaking into files, how
nice.)
In particular, this prevents subtitle packets from building up in the
subtitle queue if e.g. --vo=null is used. In this situation,
sub_get_bitmaps() is never called, and thus the segment never switched.
This also seems to help with flickering at segment switch boundaries (if
subs are supposed to be visible at the transition points).
In theory, this could trigger a switch too early, but the way VO and
subtitle renderer interact wrt. timing is a bit iffy anyway.
Glitches when resizing are still possible, but are reduced. Other VOs
could support this too, but don't need to do so.
(Totally avoiding glitches would be much more effort, and probably not
worth the trouble. How about you just watch the video the player is
playing, instead of spending your time resizing the window.)
wm4
dudemanguy
Jan Ekström
zc62
Ricardo Constantino
Niklas Haas
Leo Izen
Oleg Oshmyan
Dan Oscarsson
cantabile
Aman Gupta
Vladimir Panteleev
Niklas Haas
Richard H Lee
st4t1k