These are different AVCodecContext fields. pkt_timebase is the correct
one for identifying the unit of packet/frame timestamps when decoding,
while time_base is for encoding. Some decoders also overwrite the
time_base field with some unrelated codec metadata.
pkt_timebase does not exist in Libav, so an #if is required.
Instead of passing through double float timestamps opaquely, pass real
timestamps. Do so by always setting a valid timebase on the
AVCodecContext for audio and video decoding.
Specifically try not to round timestamps to a too coarse timebase, which
could round off small adjustments to timestamps (such as for start time
rebasing or demux_timeline). If the timebase is considered too coarse,
make it finer.
This gets rid of the need to do this specifically for some hardware
decoding wrapper. The old method of passing through double timestamps
was also a bit questionable. While libavcodec is not supposed to
interpret timestamps at all if no timebase is provided, it was
needlessly tricky. Also, it actually does compare them with
AV_NOPTS_VALUE. This change will probably also reduce confusion in the
future.
This greatly improves the result when decoding typical (ST.2084) HDR
content, since the job of tone mapping gets significantly easier when
you're only mapping from 1000 to 250, rather than 10000 to 250.
The difference is so drastic that we can now even reasonably use
`hdr-tone-mapping=linear` and get a very perceptually uniform result
that is only slightly darker than normal. (To compensate for the extra
dynamic range)
Due to weird implementation details, this only seems to be present on
keyframes (or something like that), so we have to cache the last seen
value for the frames in between.
Also, in some files the metadata is just completely broken /
nonsensical, so I decided to apply a simple heuristic to detect
completely broken metadata.
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.
This uses the normal autoprobing rules like "auto", but rejects anything
that isn't flagged as copying data back to system memory.
The chunk in command.c was dead code, so remove it instead of updating
it.
We don't have any reason to disable either. Both are loaded dynamically
at runtime anyway. There is also no reason why dxva2 would disappear
from libavcodec any time soon.
The main change is with video/hwdec.h. mp_hwdec_info is made opaque (and
renamed to mp_hwdec_devices). Its accessors are mainly thread-safe (or
documented where not), which makes the whole thing saner and cleaner. In
particular, thread-safety rules become less subtle and more obvious.
The new internal API makes it easier to support multiple OpenGL interop
backends. (Although this is not done yet, and it's not clear whether it
ever will.)
This also removes all the API-specific fields from mp_hwdec_ctx and
replaces them with a "ctx" field. For d3d in particular, we drop the
mp_d3d_ctx struct completely, and pass the interfaces directly.
Remove the emulation checks from vaapi.c and vdpau.c; they are
pointless, and the checks that matter are done on the VO layer.
The d3d hardware decoders might slightly change behavior: dxva2-copy
will not use the VO device anymore if the VO supports proper interop.
This pretty much assumes that any in such cases the VO will not use any
form of exclusive mode, which makes using the VO device in copy mode
unnecessary.
This is a big refactor. Some things may be untested and could be broken.
This uses ID3D11VideoProcessor to convert the video to a RGBA surface,
which is then bound to ANGLE. Currently ANGLE does not provide any way
to bind nv12 surfaces directly, so this will have to do.
ID3D11VideoContext1 would give us slightly more control about the
colorspace conversion, though it's still not good, and not available
in MinGW headers yet.
The video processor is created lazily, because we need to have the coded
frame size, of which AVFrame and mp_image have no concept of. Doing the
creation lazily is less of a pain than somehow hacking the coded frame
size into mp_image.
I'm not really sure how ID3D11VideoProcessorInputView is supposed to
work. We recreate it on every frame, which is simple and hopefully
doesn't affect performance.
For Mediacodec in particular we don't care about the format. It can just
decode to whatever it wants. The only case we would care about is it not
returning an opaque format if we don't have proper interop, but
libavcodec always returns non-opaque formats by default.
Use the recently added lavc_suffix mechanism to select the wrapper
decoder.
With all hwdec callbacks being optional, and RPI/Mediacodec having only
dummy callbacks, all the callbacks can be removed as well.
The result is that the vd_lavc_hwdec struct for both of them is tiny.
It's better to move them to vd_lavc.c directly, because they are so
trivial and small.
This is intended for cases when --hwdec needs to override the decoder
implementation in use, like for example on the RPI.
It does two things:
1. Allow the hwdec to indicate a decoder suffix. libavcodec by
convention adds a suffix to all wrapper decoders, and here we start
relying on it. While not necessarily the best idea, it's the only
thing we got. libavcodec's hwaccel list is useless, because it only
has the codec ID, not the associated decoder's name.
2. Make --hwdec=auto work properly. It shouldn't fail anymore, and hwdec
probing should reliably work, even if a different decoder is selected
with --vd. The semantics of --hwdec should dictate that it overrides
the default decoder.
Until now, the presence of the process_image() callback was used to set
a delay queue with a hardcoded size. Change this to a vd_lavc_hwdec
field instead, so the decoder can explicitly set this if it's really
needed.
Do this so process_image() can be used in the VideoToolbox glue code for
something entirely unrelated.
Some functions which expected a codec name (i.e. the name of the video
format itself) were passed a decoder name. Most "native" libavcodec
decoders have the same name as the codec, so this was never an issue.
This should mean that e.g. using "--vd=lavc:h264_mmal --hwdec=mmal"
should now actually enable native surface mode (instead of doing copy-
back).
AVFormatContext.codec is deprecated now, and you're supposed to use
AVFormatContext.codecpar instead.
Handle this for all of the normal playback code.
Encoding mode isn't touched.
This commit adds the d3d11va-copy hwdec mode using the ffmpeg d3d11va
api. Functions in common with dxva2 are handled in a separate decode/d3d.c
file. A future commit will rewrite decode/dxva2.c to share this code.
The mp_set_av_packet()/mp_pts_from_av() functions check whether the
timebase is set at all (i.e. AVRational.num!=0), so there's no need to
fiddle with pointers.
Completely pointless abominations that FFmpeg refuses to remove. They
are ancient, long deprecated API which we can't use anymore. They
confused users as well.
Pretend that they don't exist. Due to the way --vd works, they can't
even be forced anymore. The older hack which explicitly rejects these
can be dropped as well.
This is in preparation for a hypothetical API change in libavcodec,
which would allow the decoder to return multiple video frames before
accepting a new input packet.
In theory, the body of the if() added to vd_lavc.c could be replaced
with this code:
packet->buffer += ret;
packet->len -= ret;
but currently this is not needed, as libavformat already outputs one
frame per packet. Also, using libavcodec this way could lead to a
"deadlock" if the decoder refuses to consume e.g. garbage padding, so
enabling this now would introduce bugs.
(Adding this now for easier testing, and for symmetry with the audio
code.)
Until now (and in mplayer traditionally), avi timestamps were handled
with a timestamp FIFO. AVI timestamps are essentially just strictly
increasing frame numbers and are not reordered like normal timestamps.
Limiting the FIFO is required because frames can be dropped. To make
it worse, frame dropping can't be distinguished from the decoder not
returning output due to increasing the buffering required for B-frames.
("Measuring" the buffering at playback start seems like an interesting
idea, but won't work as the buffering could be increased mid-playback.)
Another problem are skipped frames (packets with data, but which do
not contain a video frame).
Besides dropped and skipped frames, there is the problem that we can't
always know the delay. External decoders like MMAL are not going to
tell us. (And later perhaps others, like direct VideoToolbox usage.)
In general, this works not-well enough that I prefer the solution of
passing through AVI timestamps as DTS. This is slightly incorrect,
because most decoders treat DTS as mpeg-style timestamps, which
already include a b-frame delay, and thus will be shifted by a few
frames. This means there will be a problem with A/V sync in some
situations.
Note that the FFmpeg AVI demuxer shifts timestamps by an additional
amount (which increases after the first seek!?!?), which makes the
situation worse. It works well with VfW-muxed Matroska files, though.
On RPI, the first X timestamps are broken until the MMAL decoder "locks
on".
fd339e3f53 introduced a regression that caused
segfault while uniniting dxva2 decoder (and possibly vdpau too). The problem was
that it freed the avctx earlier, before calling the backend-specific uninit
which referenced it.
Revert some of the changes of that commit, and avoid calling flush by
checking whether the codec is open instead.
(Based on a PR by Kevin Mitchell.)
Signed-off-by: wm4 <wm4@nowhere>
It can be "dangerous". In particular, the decoder might have failed to
initialize, and is now in a broken state. avcodec_flush_buffers() is not
expected to be called in this state, and could trigger undefined
behavior.
Avoids "problems". In particular, it makes MMAL output a NOPTS timestamp
if the input timestamp was NOPTS.
Don't do it for other decoders. Ideally, we will at some point in the
future switch to integer fractions for timestamps at least up until the
filter layer. But this would be a larger change, and for now I'd prefer
keeping the not-rounded demuxer timestamps (if we have them).
Commit b53cb8de added a delay queue for decoded frames. This is supposed
to be used with copy-back decoders like dxva2-copy and vaapi-copy.
Surfaces returned by them can't be referenced after uninitializing the
decoders, so they have to be released before destroying the decoder.
Move the flush_all() call above decoder uninit accordingly. Also move
the destruction of the AVFrame used for decoding (just for being
defensive - normally it doesn't hold any reference).
We just need to provide an entrypoint for it, and move the main init
code to a separate function. This gets rid of the messy video chain full
reinit in command.c, which completely destroyed and recreated the video
state for the purpose of mid-stream hw/sw switching.
Don't give the "software_fallback_decoder" field special meaning. Alwass
set it, and rename it to "decoder". Whether hw decoding is used is
determined by the "hwdec" field already.
This is mainly a refactor. I'm hoping it will make some things easier
in the future due to cleanly separating codec metadata and stream
metadata.
Also, declare that the "codec" field can not be NULL anymore. demux.c
will set it to "" if it's NULL when added. This gets rid of a corner
case everything had to handle, but which rarely happened.
