With the asynchronous slice decoding, we only queue up to 2 slices
per frames. That side effect is that now we are dequeuing bitstream
buffers in both decoding and presentation order. This would lead to
a bitstream buffer from a previous frame being dequeued instead of
the expected last slice buffer and lead to us trying to queue an
already queued bitstream buffer.
We now fix this by tracking pending requests. As request are executed
in decoding order, we marking a request done, we can effectively
dequeue bitstream buffer from all previous request, as they have been
executed already.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1395>
The decoder is not being access from multiple threads, instead it is
always protected by the streaming lock. For this reason, a
GstAtomicQueue for the request pool is overkill and may even introduce
unneeded overhead. Use a GstQueueArray in replacement, the
GstQueueArray is a good fit since the number of item is predictable and
unlikely to vary at run-time.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1395>
In slice mode, we'll do one request per slice. In order to recycle
bitstream buffer, and not run-out, wait for the last pending
request to complete and mark it done.
We only wait after having queued the current slice in order to reduce
that potential driver starvation and maintain performance (using dual
buffering).
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1395>
New plugin with an element for H.264 decoding with VA-API. This novel
approach, different from gstreamer-vaapi, uses gstcodecs library for
state handling.
The code is expected to looks cleaner because it uses VA-API without
further layers or wrappers.
* It uses the first supported DRM device as default VA display (other
displays will be supported through user's GstContext)
* Requires libva >= 1.6
* No multiview/stereo profiles neither interlaced streams because
gstcodecs doesn't handle them yet
* It is incompatible with gstreamer-vaapi
* Even if memory:VAMemory is exposed, it is not handled yet by any
other element
* Caps templates are generated dynamically querying VAAPI, but YV12
and I420 are added for system memory caps because they seem to be
supported for all the drivers when downloading frames onto main
memory, as they are used by xvimagesink and others, avoiding color
conversion.
* Surfaces aren't bounded to context, so they can grow beyond the DBP
size, allowing smooth reverse playback.
* There isn't yet error handling and recovery.
* 10-bit H.264 streams aren't supported by libva.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1379>
Current shader code is not compatible with HLSL profile "ps_4_0_level_9_3"
or lower. So d3dcompiler cannot compile our shader code in that case.
Note that VirtualBox is one known driver which doesn't support currently
implemented shader code.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1343>
It was introduced for later use of its enhanced feature over IMFSourceReader
such as taking photo with video preview, audio/video capturing at
the same time, etc. But currently it's not our use case, and it would
be maintenance burden.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1342>
This element uses the Desktop Duplication API to capture the desktop screen at high speed.
It supports Windows 8 or later.
It has the following features compared to other elements:
* Runs faster.
* It works in High DPI environment.
* Draws an accurate mouse cursor.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/863>
previous code releases GstBuffer too earlier. so we will see
ERROR default gstmsdkvideomemory.c:77:gst_msdk_video_allocator_get_surface: failed to get surface available
ERROR msdkbufferpool gstmsdkbufferpool.c:270:gst_msdk_buffer_pool_alloc_buffer:<msdkbufferpool0> failed to create new MSDK memory
We need to hold GstBuffer reference for msdk if the surfaced locked by msdk.
step to reproduce.
1. ffmpeg -f lavfi -i testsrc=duration=10:size=320x240:rate=30 -pix_fmt yuv420p -c:v libx265 test.265
2. GST_GL_PLATFORM=egl gst-launch-1.0 -v filesrc location=test.265 ! h265parse ! msdkh265dec ! queue ! glimagesink
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1277>
This sequence of event/data flow might happen
1) Initially we have one pending output event
1-1) Then, process the pending output data
2) No pending input event, then we should wait new pending input event
2-1) Wakeup by new pending event (but it's pending output event)
In above case, MFT will not report new pending input event
if pending output is not processed.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1325>
Add a new wasapi implementation mainly to support UWP application.
Basically the core logic of this plugin is almost identical to
existing wasapi plugin, but main target is Windows 10 (+ UWP).
Since this plugin uses WinRT APIs, this plugin most likely might not
work Windows 8 or lower.
Compared with existing wasapi plugin, additional features of this plugin are
* Fully compatible with both Windows 10 desktop and UWP application
* Supports automatic stream routing (auto fallback when device was removed)
* Support device level mute/volume control
But some features of existing wasapi plugin are not implemented
in this plugin yet
* Exclusive streaming mode is not supported
* Loopback feature is not implemented
* Cross-compile is not possible with current mingw toolchain
(meaning that MSVC and Windows 10 SDK are required to build this plugin)
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1264>
d3d11videosink has an advantage over d3dvideosink, such as
* Zero-copy playback with d3d11 decoders
* HDR rendering with 10-bit format/swapchain support
* UWP support
* Any system memory alignment/padding can be supported
* User can select target GPU device
And old d3dvideosink's functionality (e.g., navigation event, overlaycomposition)
can be covered by d3d11videosink
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1311>
all msdk output surfaces come from out_alloc_resp, so the buffer count is not resizable.
we need set min_buffers, max_buffers to same size.
steps to reproduce
1. ffmpeg -f lavfi -i testsrc=duration=10:size=320x240:rate=30:decimals=3 -pix_fmt yuv420p -c:v libx265 ~/bits/hevc/test.265
2. GST_GL_PLATFORM=egl gst-launch-1.0 -v filesrc location=~/bits/hevc/test.265 ! h265parse ! msdkh265dec ! msdkvpp ! queue ! glimagesink
you will see error like this:
ERROR default gstmsdkvideomemory.c:77:gst_msdk_video_allocator_get_surface: failed to get surface available
ERROR msdkbufferpool gstmsdkbufferpool.c:270:gst_msdk_buffer_pool_alloc_buffer:<msdkbufferpool2> failed to create new MSDK memory
ERROR msdkvpp gstmsdkvpp.c:297:create_output_buffer:<msdkvpp0> failed to create output video buffer
ERROR msdkdec gstmsdkdec.c:699:gst_msdkdec_finish_task:<msdkh265dec0> Failed to finish frame
ERROR msdkdec gstmsdkdec.c:1085:gst_msdkdec_handle_frame:<msdkh265dec0> Failed to finish a task
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1278>
Add MediaFoundation AAC encoder element.
Before Windows 10, mono and stereo channels were supported audio channels
configuration by AAC encoder MFT. However, on Windows 10,
5.1 channels support was introduced.
To expose correct range of support format by this element
whatever the OS version is, this element will enumerate
all the supported format by the AAC encoder MFT
and then will configure sink/src templates while plugin init.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1280>
If parent and child windows are running on different thread,
there is always a chance to cause deadlock as DefWindowProc() call
from child window thread might be blocked until the message
is handled by parent's window procedure.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1299>
GObject::dispose method can be called multiple times. As win32 d3d11window
has an internal thread and because GObject::dispose method could be called from the
thread, it might cause problems such as trying to join self-thread
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1299>
New video capture implementation using WinRT Media APIs for UWP app.
Due to the strict permission policy of UWP, device enumeration and
open should be done via new WinRT APIs and to get permission from users,
it will invoke permission dialog on UI.
Strictly saying, this implementation is not a part of MediaFoundation
but structurally it's very similar to MediaFoundation API.
So we can avoid some code duplication by adding this implementation
into MediaFoundation plugin.
This implementation requires UniversalApiContract version >= 6.0
which is part of Windows 10 version 1803 (Redstone 4)
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1241>
There was a missing break for the 4:4:4 case which would break the sizeimage
calculation. We don't currently have hardware that supports 4:4:4, so this
code wasn't tested. This was detected by Coverity.
CID 1463592 1463591
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1283>
The Cedrus driver would otherwise choose 1KB buffer, which is too small.
This follows what some drivers do, which is simply to use the size a
packed raw image would have. Specifications do not really guaranty any minimum
compression ratio.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1268>
This adds support for slice based decoder like the Allwinner/Cedrus driver. In
order to keep things efficient, we hold the sink buffer until we reach the end
of the picture. Note that as we don't know which one is last, we lazy queue the
slices. This effectively introduces one slice latency.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1268>
GstD3D11ColorConverter implementation is able to rescale video as well.
By doing colorspace conversion and rescale at once, we can save
one cycle of shader pipeline which will can save GPU resource.
Since this element can support color space conversion and rescale,
it's renamed as d3d11convert
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1275>
This commit does the following things to fix compilation on FreeBSD:
1. Add required typedefs to linux/types-compat.h.
2. Remove unnecessary include linux/ioctl.h and replace linux/types.h
with linux/types-compat.h. Both files do not exist on FreeBSD.
3. Check the header including makedev macro. FreeBSD does not have
sys/sysmacros.h, and including it unconditionally causes error.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1259>
else gst_video_meta_validate_alignment will report error like
"videometa gstvideometa.c:416:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (384) is different from the one computed from the alignment (320)"
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1224>
In section 9.3.4 a), segment_feature_mode have 0 for absolute and 1 for delta,
while in 19.2, it says the opposite. But the reference code, which usually
rules over the text state that 1 means absolute:
if (hdr->update_data)
{
hdr->abs = bool_get_bit(bool);
And uses it with that meaning to decide weither to override the existing value
or just add the detla. This fixes multiple decoding issues.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1245>
D3D11_CREATE_DEVICE_DEBUG flag will be used while creating d3d11 device
to activate debug layer. However, if system doesn't support the
debug layer for some reason, we should try to create d3d11 device
without the flag. Debug layer should be optional for device creation.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1217>
The Microsoft Media Foundation (MF) is the successor of DirectShow.
This commit includes two kinds of video capture implementation,
one uses IMFSourceReader interface which is available since Windows Vista
and the other is based on IMFCaptureEngine interface which is available
since Windows 8.
Note that this new video source element cannot be used in UWP app
for now, since device activation using those APIs are not allowed by MS.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/760>
Introduce GST_USE_NV_STATELESS_CODEC environment to allow user to select
primary nvidia decoder implementation. In case the environment
GST_USE_NV_STATELESS_CODEC=h264 was set, old nvidia h264 decoder element
will not be registered. Instead, both nvh264dec and nvh264sldec
factory name will create gstcodecs based new nvidia h264 decoder element.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1198>
Introduce GstH264Decoder based Nvidia H.264 decoder element.
Similar the element factory name of to v4l2 stateless codec,
this element can be configured with factory name "gstnvh264sldec".
Note that "sl" in the name stands for "stateless"
For now, existing nvh264dec covers more profile and formats
(e.g., interlaced stream) than this implementation.
However, this implementation allows us to control lower level
parameters such as decoded picture buffer management and therefore
we can get a chance to improve performance in terms of latency.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1198>
The render width/height and the vinfo was only saved upon renegotiation. This
fixes the problem by saving this metadata at the same time the buffer is
saved. The saved copy of this is needed for expose() and drain() virtual functions.
This fixes various assertion that happens on drain query.
in C, & is weaker than the ! operator and clang is giving the following
error about it.
```
../subprojects/gst-plugins-bad/sys/msdk/gstmsdkdec.c:731:7: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
if (!gst_msdk_context_get_job_type (thiz->context) & GST_MSDK_JOB_DECODER) {
^ ~
../subprojects/gst-plugins-bad/sys/msdk/gstmsdkdec.c:731:7: note: add parentheses after the '!' to evaluate the bitwise operator first
if (!gst_msdk_context_get_job_type (thiz->context) & GST_MSDK_JOB_DECODER) {
^
( )
../subprojects/gst-plugins-bad/sys/msdk/gstmsdkdec.c:731:7: note: add parentheses around left hand side expression to silence this warning
if (!gst_msdk_context_get_job_type (thiz->context) & GST_MSDK_JOB_DECODER) {
^
( )
1 error generated.
```
Too many decode surface would waste GPU memory. Also it seems to be
introducing additional latency depending on stream. Since nvcodec
sdk version 9.0, CUVID parser API has been providing the minimum
required number of surface. By using it, we can save GPU memory
and reduce possible latency.
We should directly check the values of the `debug` and `optimization`
options instead.
`get_option('buildtype')` will return `'custom'` for most combinations
of `-Doptimization` and `-Ddebug`, but those two will always be set
correctly if only `-Dbuildtype` is set. So we should look at those
options directly.
For the two-way mapping between `buildtype` and `optimization`
+ `debug`, see this table:
https://mesonbuild.com/Builtin-options.html#build-type-options
This code add required mechanism to try and allocate (not implemented yet)
otherwise wait for more buffers. This also comes with mechanism to terminate
the wait on flush or PAUSED_TO_READY transitions.
Use a goto to ensure that for all cases we cleanup the current picture state.
And move the src buffer allocation higher, so we don't queue a bitstream
buffer if we don't have a picture buffer to decode into.
This allow negotiating the output format through caps. Some drivers can
pipeline the decoder buffer through an image processor. This only support
colorspace conversion for now.
This implements driver stride support but only for single allocation buffers.
This code is imported from the original v4l2 plugin and adapted to the new
helper context.
In some case, when downstream does not support GstVideoMeta, we need to
normalize the stride and offset of the buffer so that downstream can render
properly with a GstVideoMeta. This code is not called when GstVideoMeta is
supported downstream.
In this patch we strictly set the GstVideoMeta width/height to the coded width
and height. Further patches will add stride support and frame copying when
downstream does not support GstVideoMeta.
Don't let downstream cause a renegotiation at random point in time. This would
lead to spurious renegotiation and the decoder state may not be recoverable.
We now pass the controls, associated to a request, queue the bitstream, qeueue
a picture buffer to decode into and finally queue the request. This now runs
until the buffer pool is exhausted. The next step will be to dequeue.
In this patch we fill the control structure with the bitstream paramter and
copy the bitstream data into V4L2 memory. Slice paramters are only the subset
of what Hantro needs, without any support for interlaced content.
This is a pooling allocator and the buffer pool does nothing other then
reusing the GstBuffer structure. Note that the pool is an internal pool, so
the start/stop/set_config virtual functions are not implemented.
This introduces the skeleton of the H264 decoder. The plugin will list the
devices and register a subclass of the GstV4L2CodecH264Dec base class. The
subclass will pick the required specific information from the GstV4L2Device
stored in the subclass structure.
This is a GstObject which will be used to hold on media and video device file
descriptor and provide abstracted ioctl calls with these descriptor. At the
moment this helper contains just enough to enumerate the supported format.
This part will be used by the plugin to register the CODEC specific elements..
Most of the features we need are very early or not expose yet in the uAPI.
Using an internal copy ensure that we everything we need is defined avoiding
to add load of checks and conditionnal code.
This introduces a GstV4L2CodecDevice structure and helper to retrieve a
list of CODEC device drivers. In order to find the device driver we
enumerate all media devices with UDEV. We then get the media controller
topology and locate a entity with function encoder or decoder and make
sure it is linked to two V4L2 IO entity pointing to the same device
node.
The media driver can support HEVC 8-bit 422 encoding for non-lowpower
mode since ICL[1], so VPP is not needed for this case.
Sample pipeline:
gst-launch-1.0 videotestsrc ! video/x-raw,format=YUY2 ! msdkh265enc ! \
filesink location=output.h265
[1] https://github.com/intel/media-driver#decodingencoding-features
DXVA supports two kinds of texture structure for DPB, one is
"1) texture array" and the other is "2) array of texture".
1) is a type of texture which is single ID3D11Texture2D object having
ArraySize greater than one. So the ID3D11Texture2D itself is a set of texture.
Each sub texture of this type mush have identical resolution, format and so on,
and the number of sub texture in a texture array is fixed.
2) is an array of usual ID3D11Texture2D object. That means each
ID3D11Texture2D is independent each other and might have different resolution as well.
Moreover, we can modify the number of frames of the array dynamically.
This type is more flexible than "1) texture array" in terms of dynamic
behavior and also this type of texture can be used for shader resource view
but "1) texture array" couldn't be.
If "2) array of texture" is supported by driver, DXVA spec is saying that
it's preferred format over "1) texture array" in terms of performance.
The set of supported color space by DXGI is not full combination of
our colorimetry. That means we should convert color space to one
of supported color space by DXGI. This commit modifies the color space
selection step so that d3d11window can find the best matching DXGI color space
first and then the selected input/output color space will be referenced
by shader and/or d3d11videoprocessor.
Adds properties to the devices listed in GstDeviceMonitor by the
applemedia plugin.
These properties are:
- device.api (always set to "avf")
- avf.unique_id
- avf.model_id
- avf.manufacturer (except on iOS)
- avf.has_flash
- avf.has_torch
Everything except device.api is taken directly from the AVCaptureDevice object
provided by AVFoundation.
VP9 codec allows resizing reference frame by spec. Handling this case
is a bit tricky especially when the resizing happens on non-keyframe,
because pre-allocated decoder textures (i.e., dpb) have negotiated
resolution and to change resolution meanwhile decoding on non-keyframe,
each texture might need to be re-created, copied to new dpb somehow,
and re-negotiated with downstream.
Due to the complicated requirement of negotiation driven
resizing handling, this commit adds shader into d3d11decoder object
to resize only corresponding frames. Note that if the resolution change
is detected on keyframe, decoder will re-negotiate with downstream.
Not only any textures for decoder output view, any destination texture
which would be copied from decoder output texture need to be aligned too.
Otherwise driver sometimes crashed/hung (not sure why).
Resolution of NV12, P010, and P016 formats must be multiple of two.
Otherwise texture cannot be created. Instead of doing this alignment
per API consumer side, do this in buffer pool for simplicity.
Now that the system_frame_number is saved on the pictures we can use
gst_video_decoder_get_frame() helper instead of getting the full list
and looping over it.
On new_segment, the decoder is expected to negotiate. The decoder may want to
pre-allocate the needed buffers. Pass the max_dpb_size as this is needed to
determin how many buffers should be allocated.
This introduce a library which contains a set of base classes which
handles the parsing and the state tracking for the purpose of decoding
different CODECs. Currently H264, H265 and VP9 are supported. These
bases classes are used to decode with low level decoding API like DXVA,
NVDEC, VDPAU, VAAPI and V4L2 State Less decoders. The new library is
named gstreamer-codecs-1.0 / libgstcodecs.
This commit moves parsing code for superframe and frame header into
handle_frame() method, and removes parse() implementation from vp9decoder
baseclass.
The combination of
- multiple frames are packed in a given input buffer (i.e., superframe)
- reverse playback
seems to be complicated and also it doesn't work as intended in some case
The most common audio sample rate in AV streams is 48kHz, and the most
common device output sample rate is 48kHz. This allows handing of 48kHz
input streams without resampling.
Remove comments about avoiding the use of 48kHz.
This change is needed to support 2K DCI video modes.
Version 10.8 of the Decklink SDK supported DCI video modes for output
only. This updated version drops that restriction.
The current latest version of the Decklink SDK is 11.5, however
the gstreamer decklink plugin is not compatible with API changes
introduced in version 11 of the SDK. Therefore I have opted to upgrade
to the latest 10.x version instead.
* Remove redundant variables for width/height and par from GstD3D11Window.
GstVideoInfo holds all the values.
* Don't need to pass par to gst_d3d11_window_prepare().
It will be parsed from caps again
* Remove duplicated math
Fixing regression of the commit 9dada90108
gst_d3d11_result() will print warning message when HRESULT != S_OK.
However, since the retry is trivial stuff, check hr == E_PENDING first
and do not warn it.
The DXGI_PRESENT_ALLOW_TEARING flag might cause unexpected tearing
side effect. Setting it in fullscreen mode only seems to be
the correct usage as in the Microsoft's direct3d examples.
DXVA spec is saying that the size of bitstream buffer provided by hardware decoder
should be 128 bytes aligned. And also the host software decoder should
align the size of written buffer to 128 bytes. That means if the slice
(or frame in case of VP9) size is not aligned with 128 bytes,
the rest of non 128 bytes aligned memory should be zero-padded.
In addition to aligning implementation, some variables are renamed
to be more intuitive by this commit.
This implementation is similar to what we've done for nvcodec plugin.
Since supported resolution, profiles, and formats are device dependent ones,
single template caps cannot represent them, so this modification
will help autoplugging and fallback.
Note that the legacy gpu list and list of resolution to query were
taken from chromium's code.
gst_video_frame_copy will copy input frame to stating texture
of fallback frame. Then, we need to map fallback texture with GST_MAP_D3D11
flag to upload the staging texture to render texture. Otherwise
the render texture wouldn't be updated.
Source texture (decoder view) might be larger than destination (staging) texture.
In that case, D3D11_BOX structure should be passed to CopySubresourceRegion method
in order to specify the exact target area.
DXGI_SWAP_EFFECT_DISCARD cannot be used with dirty rect drawing feature
of IDXGISwapChain1::Present().
Note that IDXGISwapChain1 interface is available on Platform Update for Windows 7
and DXGI_SWAP_EFFECT_FLIP_SEQUENTIAL is also the case.
Use resolution specified in caps for input_rect instead of
passed width and height value. The width and height might be modified
ones by d3d11videosink, then frame resolution might be different.
* Move decoding process to handle_frame
* Remove GstVideoDecoder::parse implementation
* Clarify flush/drain/finish usage
In forward playback case, have_frame() call will be followed by
handle_frame() but reverse playback is not the case.
To ensure GstVideoCodecFrame, the decoding process should be placed inside
of handle_frame(), instead of parse().
Since we don't support alignment=nal, the parse() implementation is not worth.
In order to fix broken reverse playback, let's remove the parse()
implementation and revisit it when adding alignment=nal support.
... and remove unused start, stop method from subclass.
Current implementation does not require subclass specific behavior
for the handle_frame() method.
Actually our buffer pool size and the number of backbuffer are
independent. In case of reverse playback, upstream might request
a lot of buffers (up to GOP size).
The class data with the caps in it will be leaked if the element is
registered but never instantiated. There is no way around this. Mark
the caps as such so that the leaks tracer does not warn about it.
This is the same as pad template caps getting leaked, which are also
marked as may-be-leaked. These objects are initialized exactly once,
and are 'global' data.
video/x-vp9 is required in the src pad, however the output includes a
IVF header, which makes the pipeline below doesn't work
gst-launch-1.0 videotestsrc ! msdkvp9enc ! msdkvp9dec ! fakesink
Since mfx 1.26, the VP9 encoder supports bitstream without IVF header,
so in this patch, the mfx version is checked and msdkvp9enc is enabled
only if mfx 1.26+ is available
Android 25 added support for i-frame-interval to be a floating
point value. Store the property as a float and use the newer
version when it's available.
