Was probably worthless, and I can't measure a difference anymore (I used
to be able and it still seemed worth doing so back then).
When the default buffer size is enlarged in the next commit, the inline
buffer probably won't even be useful in theory, because the data will
rarely be on the same page as the other stream fields. It surely makes
the inline buffer seem like a ridiculous micro-optimization. Farewell...
In some corner cases (see #6802), it can be beneficial to use a larger
stream buffer size. Use this as argument to rewrite everything for no
reason.
Turn stream.c itself into a ring buffer, with configurable size. The
latter would have been easily achievable with minimal changes, and the
ring buffer is the hard part. There is no reason to have a ring buffer
at all, except possibly if ffmpeg don't fix their awful mp4 demuxer, and
some subtle issues with demux_mkv.c wanting to seek back by small
offsets (the latter was handled with small stream_peek() calls, which
are unneeded now).
In addition, this turns small forward seeks into reads (where data is
simply skipped). Before this commit, only stream_skip() did this (which
also mean that stream_skip() simply calls stream_seek() now).
Replace all stream_peek() calls with something else (usually
stream_read_peek()). The function was a problem, because it returned a
pointer to the internal buffer, which is now a ring buffer with
wrapping. The new function just copies the data into a buffer, and in
some cases requires callers to dynamically allocate memory. (The most
common case, demux_lavf.c, required a separate buffer allocation anyway
due to FFmpeg "idiosyncrasies".) This is the bulk of the demuxer_*
changes.
I'm not happy with this. There still isn't a good reason why there
should be a ring buffer, that is complex, and most of the time just
wastes half of the available memory. Maybe another rewrite soon.
It also contains bugs; you're an alpha tester now.
This is something relatively frequently needed, and there must be half a
dozen ad-hoc implementations in mpv. The next commit uses this, the
suspected duplicate implementations are hiding.
The old code made it depend on ->seekable. If it isn't seekable, and
something discarded the data, then it'll just show an error message,
which will at least be somewhat informative. If no data was discarded,
the seek call is always a no-op.
There's a weird "timeline" condition in the old code; this doesn't
matter anymore, because timeline stuff does not pass streams down to
nested demuxers anymore.
tv:// and pvr:// are gone, DVD almost. The former didn't really have any
uses left, except webcams. Provide a replacement example for that.
We don't need a separate section for DVD. If you use DVD, you're on your
own. There's still enough documentation left to puzzle things together
even if you don't read the source code.
Not like anyone reads it. Although putting all this text before listing
the allowed option values sort of has the intention to discourage users
from using the option at all. Advertise Ctrl+h, which is a decent way of
enabling hardware decoding temporarily.
They were used at some point, but then fell into disuse. In general,
these old flags are all a bit fuzzy, so it's a good idea to remove them
as much as possible.
The comment about MP_IMGFLAG_PAL isn't true anymore. The old meaning was
deprecated at some point, and the flag was removed from "pseudo
paletted" formats. I think mpv at one point changed its own flag from
AV_PIX_FMT_FLAG_PSEUDOPAL to AV_PIX_FMT_FLAG_PAL, when the former was
deprecated, and it became unnecessary to allocate a palette for
non-paletted formats. (The one who deprecated in FFmpeg was me, if you
wonder.)
MP_IMGFLAG_PLANAR was used in command.c, use a relatively similar flag
as replacement.
This is slightly helpful for testing, and otherwise useless and without
consequence.
I'm not using the correct output format and using IMGFMT_RGB0 as
placeholder. This doesn't matter currently, as both sws and zimg support
this as output (and support any input for it). I'm doing this because
it's surprisingly tricky to get the correct output format at this point,
without digging deeper into x11 shit or refactoring parts of the VO. I
don't care enough about this.
The user can raise the number of tolerated hardware decoding errors. On
the other hand, we have a static limit on packets that are "saved" for
fallback handling (and that's a good idea to avoid unbounded memory
usage). In this case, it could happen that the start of a file was fine
after a fallback, but after that buffered amount of data, it would
suddenly skip.
It's more useful to skip buffering entirely if the number of tolerated
decoding errors exceeds the fixed buffer.
(And also, I'm sure nobody gives a shit about this feature.)
prepare_decoding() returned a bool that was supposed to tell whether
decoding could work, or if something was fucked. After recent changes to
the decoder loop, this did not work anymore, and caused an endless loop.
Redo it, so it makes more sense. avctx being NULL (software fallback
initialization failed) now signals EOF. hwdec_failed needs to be handled
on send_packet() only, where it probably never happens anyway.
(Who was the idiot who made libavcodec have two entrypoints for
decoding? Oh right, it was me. PEBKAC.)
Shovel the code around to make the data flow slightly simpler (?). At
least there's only one send_packet function now. The old code had the
problem that send_packet() could be called even if there were queued
packets; due to sending the queued packets in the receive_frame
function, this should not happen anymore (the code checking for this
case in send_packet should normally never be called).
Untested with actual full stream hw decoders (none available here); I
created a test case by making hwaccel decoding fail.
Forgotten in commit 5d5fdb7. This failed to return the error code
properly. In particular, if the decoder rejected the packet, this was
not properly detected. Normally, this mattered only in specific cases.
Fixes: #7115
MPlayer isn't all too well-known anymore. It does not make sense to
"advertise" with it (and it actually never did).
The GPU comment needed clarification. I think originally, it was just to
signal that you'll have a bad time with Intel. Make that broader.
Instead, use a YUV planar format. It doesn't matter, since we use the
format only internally and for "management" purposes. We're only
interested in the physical layout, not what colorspace FFmpeg "forcibly"
associates with it.
Also get rid of using the old and slightly sketchy mp_imgfmt_find()
function. Yep, the IMGFMT_RGB30 now "constructs" the planar format,
instead of using a pixfmt constant. Slightly inconvenient, tricky, and
fragile, but I like it, so bugger off.
This whole thing gets rid of some of the strange plane permutations that
were needed earlier.
According to the definition of the GL format, and the definition in
img_format.h, and the actual output by vo_gpu, the order of components
was probably wrong. It's exceedingly likely that the vo_drm format (for
which this was originally written) has the same layout, so this was
probably a bug from when the zimg wrapper code was refactored.
This was too hardcoded to libswscale. In particular, IMGFMT_RGB30 output
is only possible with the zimg wrapper, so the context needs to be taken
into account (since this depends on the --sws-allow-zimg option
dynamically). This is still slightly risky, because zimg currently will
still fall back to swscale in some cases, such as when it refuses to
initialize the particular color conversion that is requested.
f_autoconvert.c could actually handle this better, but I'm tool fucking
lazy right now, and nobody cares anyway, so go away, OK?
This integrates it as "special" format, with no alpha component, as the
equivalent IMGFMT_RGB30 isn't meant to contain any.
Nothing can produce this format in the video chain yet, so the next
commits are needed to make this actually work.
Sometimes the atlas can get so large that it exceeds the maximum allowed
size for an mp_image. Since the atlas will never shrink naturally, this
breaks subtitles entirely until mpv is restarted. Reset the packer so
that subtitles can rendered properly once the atlas fits again.
This is a partial workaround for #6286.
The statement about the display FPS is outdated by several years.
"audio"-sync mode does not use the display FPS anymore, and that it's
X11 only also isn't true anymore.
These modes have separate implementations for audio and display video
sync. modes, so the explanations are separate.
Why the hell are users playing around with this anyway? The explanations
are probably too special to make sense for anyone who doesn't know the
code (and who knows the code doesn't need them anyway), but whatever.
This is mostly just because of the odd RGB default gamma issue, which
shouldn't have any real impact. This also sets allow_approximate_gamma,
which I hope is fine for normal use cases.
Normally, the Y plane can just be passed directly to zimg, and only the
chroma plane needs to be (de)interleaved. It still needs a copy if the Y
pointer is not aligned, though. (Whether this is actually a problem
depends on the CPU and probably zimg's compiler.)
This requires deciding per plane whether the plane should go through the
repack buffer or not. This logic is active in non-nv12 cases, because
not doing so would require extra code (maybe 2 lines or so).
repack_align is now always called, even if it's planar->planar with all
input aligned, but it won't actually do anything in that case. The
assumption is that zimg won't change behavior if you pass a callback
that does nothing versus passing NULL as callback.
This is for formats like nv12 (including p010, nv24, etc.). Might be
important for hardware decoding. Previously, this would have forced a
libswscale fallback.
The genericism makes this only slightly more complicated. The main
complication is due to the fact that mixing planar and packed stuff is
insane (thanks, Nvidia).
P010 output will actually happily set any of the 6 bit "padding" LSB,
that are normally supposed to be 0 (for unpadded data there is P016).
Scaling happens with 16 bit precision. Not going to bother adding an
extra packer which zeros them out, or with shifting them in
packing/unpacking. Lets just hope nobody notices.
This is similar to mp_imgfmt_find(), but probably a bit saner. Used by
the next commit. The previous commit is required to map this
unambiguously between all formats.
As the code comment says, this is needed to disambiguate FFmpeg formats.
This struct only describes the "physical" layout of a format, while
FFmpeg also attaches part of the colorspace information to the format.
We've set all planes to the same zmask. But for subsampled chroma, the
zmask obviously needs to be smaller. This could lead to out of bounds
memory read and write accesses.
Move the align repacker to a single function, since this is now more
convenient.
Make the existing "not found" messages debug only, and add a new verbose
message if a config file was opened. The idea is that logging should
make it apparent whether or not config files are loaded, and it's more
common to use scripts without config files, leading to fewer log
messages in verbose mode.
demux_mkv has lots of logging that shows information about the file. It
sort of reminds of mkvinfo output. While this is sometimes interesting,
it's too much for verbose mode, and should be in debug log level.
In 2017, we lowered this to debug level. But I think setting options is
important enough that it should be logged even in verbose, at least
compared to all the other dumb noise.
This might be reduced again if verbose logging becomes much cleaner.
This probably covers all packed formats which have byte-aligned
component, no alpha, and no subsampling. Everything else needs more
imgfmt metadata, or something even more complicated. Alpha is primarily
not supported, because zimg requires a second scaler instance for it,
and handling packing/unpacking with it is an unacceptable mess.
Raise swscale and zimg default parameters. This restores screenshot
quality settings (maybe) unset in the commit before. Also expose some
more libswscale and zimg options.
Since these options are also used for VOs like x11 and drm, this will
make x11/drm/etc. much slower. For compensation, provide a profile that
sets the old option values: sw-fast. I'm also enabling zimg here, just
as an experiment.
The core problem is that we have a single set of command line options
which control the settings used for most swscale/zimg uses. This was
done in the previous commit. It cannot differentiate between the VOs,
which need to be realtime and may accept/require lower quality options,
and things like screenshots or vo_image, which can be slower, but should
not sacrifice quality by default.
Should this have two sets of options or something similar to do the
right thing depending on the code which calls libswscale? Maybe. Or
should I just ignore the problem, make it someone else's problem (users
who want to use software conversion VOs), provide a sub-optimal
solution, and call it a day? Definitely, sounds good, pushing to master,
goodbye.
Lots of dumb crap to do... something. Instead of adding yet another dumb
helper, just use the main" sws_utils API in both callers. (Which,
unfortunately, has been duplicated for glorious webp screenshots,
despite the fact that webp is crap.)
Good part: can enable zimg for screenshots (as far as needed).
Bad part: uses "default" swscale parameters instead of HQ now.
wm4
Dan Elkouby