The AudioClient3 API is only available on Windows 10, and we will
automatically detect when it is available and use it.
However, using it for capturing audio with low latency and without
glitches seems to require setting the realtime priority of the entire
pipeline to "critical", which we cannot do from inside the element.
Hence, we can only enable that by default for wasapisink since
apps should be able to safely set the low-latency property to TRUE if
they need low-latency capture or playback.
This allows us to request ultra-low-latency device periods even in
shared mode. However, this requires good drivers and Windows 10, so
we only enable this when we detect that we are running on Windows 10
at runtime.
You can forcibly disable this feature on Windows 10 by setting
GST_WASAPI_DISABLE_AUDIOCLIENT3=1 in the environment.
Since there is already an "adaptive-B" option, just
use boolean property for B-pyramid enabling.
Fixme: Not sure whether this can be supported in vp8 and vp9.
It could be possible through GPB (b without backward ref) but
can't verify currently. We can move this as common property
once verified with vp8 and vp9 without breaking any backward
compatibility.
https://bugzilla.gnome.org/show_bug.cgi?id=791637
Add a new property "trellis" to enable trellis quantization.
Keeping trellis as a flag value (which is boolean for gst x264 enc element)
since it is possible to enable/disable this seperately for
I,P and B frames through MediaSDK ext option headers.
The subclass implementations always need to inform base-encoder
if it requires the inclusion of Extend Header buffers (mfxExtCodingOption2
and mfxExtCodingOption3).
https://bugzilla.gnome.org/show_bug.cgi?id=791637
This option controls down sampling in look ahead bitrate
control mode. According to spec it is only supported in AVC.
Fixme: Probably HEVC also have support for this in recent
MSDK versions. We could move the enumeration types to common
header usable for multiple codecs.
https://bugzilla.gnome.org/show_bug.cgi?id=791637
MediaSDK has support for a number of rate control algorithms.
Adding all possible options to the property rate-control.
Fixme1: In case of failure, currently we don't have a proper method
to show which rate-control has been failed. It could be better
to add some extensive validation on EncQuery output in case of error.
Unfortunately, not all ratecontrol methods are supported by every codecs
and we don't have the dynamic detection of supported ratecontrol methods yet.
https://bugzilla.gnome.org/show_bug.cgi?id=791637
We have the property "i-frames" to set the IDR interval in a
gop. Unfortunately MSDK HEVC encoder behaves bit differently
for IdrInterval field, IdrInteval == 1 indicate every
I-frame should be an IDR (which is IdrInterval == 0 for other codecs),
IdrInteval == 2 means every other I-frame is an IDR
(which is IdrInterval == 1 for other codecs) etc.
So we generalize the behaviour of property "i-frames" by
incrementing the value by one in each case (only for HEVC).
https://bugzilla.gnome.org/show_bug.cgi?id=791637
The base encoder common properties are not valid for
mjpeg encoder where there is no motion compensation or rate control.
Delaying the property installation on the base gobject
untill the subclass class_init get invoked.
https://bugzilla.gnome.org/show_bug.cgi?id=791637
The gst-msdk decoders prefer packetized streams as input
and in this case we can avoid unnecessary input bitstream copy
to mfxBitstream. This works fine for codecs like h264 where
we only support byte-stream with au alignment. Other format
conversions should be done thorugh parsers. But this won't work
for codecs like vc1 where we don't have an autoplugged parser.
Even the parser is not capable to do format conversions.
Packetizing through base decoders parse() routine will bring a
lot of uncecessary of complexities and codecparser libraray dependency.
So we just use an interal gst_adaper to keep track of bitstream
which is not consumed by msdk durig AsynchronusDecoding.
This adapter will get used only if subclass implementations
set the "is_packetized" to FALSE for msdk base encoder.
https://bugzilla.gnome.org/show_bug.cgi?id=792589
Adding Simple and Main profiles decode support.
Currently msdkvc1dec is not capable to handle the codec_data,
only instream headers are supported. Also msdk vc1 decoder
expecting instream with Sequence header as per SMPTE 421M Annex L.
Most of the decdoebin/playbin pipeline won't work with the above
constraints
because vc1parse is still not an autoplug element.
Only way to make mskdvc1dec work is by connecting a vc1parse
as an upstream element.
https://bugzilla.gnome.org/show_bug.cgi?id=792589
Use drm render node as the first choice of device node file.
Fall backs to use drm primary (/dev/dri/card[0-9])
if there is no render node available
Basic logic is inherited from gstreamer-vaapi, but using
gudev API rather than libudev directly.
Added gudev library as dependency for msdk.
https://bugzilla.gnome.org/show_bug.cgi?id=791599
1\ If downstream's pool is MSDK bufferpool,
2\ If there's shared GstMsdkContext in the pipeline,
a decoder decides to use video memory.
This policy should be improved to handle more cases.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
In case that pipeline is like ".. ! decoder ! encoder ! ..." with using
video memory,
decoder needs to know the async depth of the following msdk element so
that it could
allocate the correct number of video memory.
Otherwise, decoder's memory is exhausted while processing.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
How to share/create GstMsdkcontext is the following:
- Search GstMsdkContext if there's in the pipeline.
- If found, check if it's decoder, encoder or vpp by job type.
- If it's same job type, it creates another instance of
GstMsdkContext
with joined-session.
- Otherwise just use the shared GstMsdkContext.
- If not found, just creates new instance of GstMsdkContext.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
According to the driver's instruction, if there are two or more encoders
or decoders in a process, the session should be joined by
MFXJoinSession.
To achieve this successfully by GstContext, this patch adds job type
specified if it's encoder, decoder or vpp.
If a msdk element gets to know if joining session is needed by the
shared context,
it should create another instance of GstContext with joined session,
which
is not shared.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
1\ In decide_allocation, it makes its own msdk bufferpool.
- If downstream supports video meta, it just replace it with the msdk
bufferpool.
- If not, it uses the msdk bufferpool as a side pool, which will be
decoded into.
and will copy it to downstream's bufferpool.
2\ Decide if using video memory or system memory.
- This is not completed in this patch.
- It might be decided in update_src_caps.
- But tested for both system memory and video memory cases.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
1\ Proposes msdk bufferpool to upstream.
- If upstream has accepted the proposed msdk bufferpool,
encoder can get msdk surface from the buffer directly.
- If not, encoder get msdk surface its own msdk bufferpool
and copy from upstream's frame to the surface.
2\ Replace arrays of surfaces with msdk bufferpool.
3\ In case of using VPP, there should be another msdk bufferpool
with NV12 info so that it could convert first and encode.
Calls gst_msdk_set_frame_allocator and uses video memory only on linux.
and uses system memory on Windows until d3d allocator is implemented.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
Implements 2 memory allocators:
1\ GstMsdkSystemAllocator: This will allocate system memory.
2\ GstMsdkVideoAllocator: This will allocate device memory depending
on the platform. (eg. VASurface)
Currently GstMsdkBufferPool uses video allocator currently by default
only on linux. On Windows, we should use system memory until d3d
allocator
is implemented.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
Implements msdk frame allocator which is required from the driver.
Also makes these functions global so that GstMsdkAllocator could use
the allocated video memory later and couple with GstMsdkMemory.
GstMsdkContext keeps allocation information such as mfxFrameAllocRequest
and mfxFrameAllocResponse after allocation.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
Makes GstMsdkContext to be a descendant of GstObject so that
we could track the life-cycle of the session of the driver.
Also replaces MsdkContext with this one.
Keeps msdk_d3d.c alive for the future.
https://bugzilla.gnome.org/show_bug.cgi?id=790752
Same changes as done for wasapisink in cbe2fc40a. Turns out this is
sometimes also needed for capture. Reported by Mathieu_Du.
Also improve logging in that case for easier debugging.
Sometimes the minimum period advertised by a card results in an
unaligned buffer size error during initialization in exclusive mode.
In that case, we can fetch the actual buffer size in frames and
calculate the period from that.
We can't do this pre-emptively because we can't call GetBufferSize
till Initialize has been called at least once.
https://bugzilla.gnome.org/show_bug.cgi?id=793289
This reduces the chances of startup glitches, and also reduces the
chances that we'll get garbled output due to driver bugs.
Recommended by the WASAPI documentation.
https://bugzilla.gnome.org/show_bug.cgi?id=793289
So far, we have been completely discarding the values of latency-time
and buffer-time and trying to always open the device in the lowest
latency mode possible. However, sometimes this is a bad idea:
1. When we want to save power/CPU and don't want low latency
2. When the lowest latency setting causes glitches
3. Other audio-driver bugs
Now we will try to follow the user-set values of latency-time and
buffer-time in shared mode, and only latency-time in exclusive mode (we
have no control over the hardware buffer size, and there is no use in
setting GstAudioRingBuffer size to something larger).
The elements will still try to open the devices in the lowest latency
mode possible if you set the "low-latency" property to "true".
https://bugzilla.gnome.org/show_bug.cgi?id=793289
This requires using allocated strings, but it's the best option. For
instance, a call could fail because CoInitialize() wasn't called, or
because some other thing in the stack failed.
https://bugzilla.gnome.org/show_bug.cgi?id=793289
This is particularly important when running in exclusive mode because
any delays will immediately cause glitching.
The MinGW version in Cerbero is too old, so we can only enable this when
building with MSVC or when people build GStreamer for MSYS2 or other
MinGW-based distributions.
To force-enable this code when building with MinGW, build with
CFLAGS="-DGST_FORCE_WIN_AVRT -lavrt".
https://bugzilla.gnome.org/show_bug.cgi?id=793289
This provides much lower latency compared to opening in shared mode,
but it also means that the device cannot be opened by any other
application. The advantage is that the achievable latency is much
lower.
In shared mode, WASAPI's engine period is 10ms, and so that is the
lowest latency achievable.
In exclusive mode, the limit is the device period itself, which in my
testing with USB DACs, on-board PCI sound-cards, and HDMI cards is
between 2ms and 3.33ms.
We set our audioringbuffer limits to match the device, so the
achievable sink latency is 6-9ms. Further improvements can be made if
needed.
https://bugzilla.gnome.org/show_bug.cgi?id=793289
