g_string_free(.., FALSE) gives us ownership of the string
already, no need to duplicate that again with g_strdup(),
and doing so will leak the string returned by g_string_free()
here. Caught by compiler warnings in newer GLib versions.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4273>
Fix compiler warnings about not using the return value when
freeing the GString segment with g_string_free(.., FALSE):
ignoring return value of ‘g_string_free_and_steal’ declared with attribute ‘warn_unused_result’
which we get with newer GLib versions. These were all harmless.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4273>
Specification says:
"""
engineVersion is an unsigned integer variable containing the developer-supplied
version number of the engine used to create the application.
"""
Assuming the engine is GStreamer, it would be expected to set its version as
engine version.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4243>
This is a follow-up of the previous commit that enabled support for redirection.
The problem is that the urisourcebin that emitted the error redirection never
produced any pads, and therefore was never linked to decodebin3. This resulted
in the code waiting for that (output) item to finally switch over ... which will
never happen.
The fix is done by removing it early if it was never connected to decodebin3.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4252>
With GST_SEEK_FLAG_SNAP_AFTER present, the previous version would
adjust seek time based on the keyframe farthest away from desired_time.
This was incorrect, because we always want the *earliest* suitable keyframe
to seek to, not the last one.
With this fix, in case of the SNAP_AFTER, we now look for the closest keyframe
that can be found after desired_time. Behaviour for SNAP_BEFORE should remain
unchanged.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4183>
Trying to run the `janus` Rust `gst-example`, `tungstenite` reports:
> Missing, duplicated or incorrect header sec-websocket-key
Indeed, all mandatory headers from the following list are missing
(code from `tungstenite:🤝:client::generate_request`):
```rust
const WEBSOCKET_HEADERS: [&str; 5] =
["Host", "Connection", "Upgrade", "Sec-WebSocket-Version", KEY_HEADERNAME];
```
These headers are mandatory for the websocket handshake. This feature is
selected by async-tungstenite.
Prior to this commit, the HTTP request was created with the header
"Sec-WebSocket-Protocol" only. Delegating the request creation to tungstenite
adds the missing headers.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4240>
Assuming that V4L2 CAPTURE devices always use one buffer per JPEG image, we can
always mark JPEGs provided by a V4L2 element as parsed.
The V4L2 elements require that JPEG images sent to V4L2 OUTPUT devices must
always be parsed.
This is necessary to link a V4L2 CAPTURE device with a V4L2 OUTPUT device
without explicitly marking the stream as parsed or adding a jpegparse into the
pipeline.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4229>
The goal of parsebin is to figure out which elements to link together in order
to provide elementary streams given any random input.
The problem is that deciding whether a given stream should still have more
elements plugged in or not was dependent on ... the presence of compatible
decoders (sic).
Instead of that, if we can't plug anymore elements on a given stream *and* it is
detected as being an elementary stream, expose it.
Fixes#2118
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4231>
In the same spirit of libva-win32 elements this patch shows the driver of each
element in gst-inspect, giving more information to the user. This driver
description is parsed from vaQueryVendorString from mesa and intel drivers,
while copied as is for others. Also appends the render node for multi gpu
systems.
Fixes#2349
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4204>
There's no guarantee it will *actually* be the URI which refered to what we are
downloading. It could be a stream URI or anything else.
Instead of putting something wrong, put no (specific) referer as a better choice
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3972>
Otherwise application would not be able to know matching element
for wanted device. Typical use case of the read-only device path
(DXGI Adapter LUID, CUDA device index, etc) property is that
application enumerates physical devices and then selects matching
GStreamer element (in null state) via device path property.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4220>
If sticky events are present on parsebin source pads, we propagate them to the
multiqueue source pads. Those will be propagated on the new urisourcebin source
pads like in the other code paths.
This ensures that STREAM_START event are present on new source pads. If CAPS
event are also present (not guaranteed), they will also be available.
Fixes#2384
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4203>
H.265 NAL always have 2 bytes of headers. Unlike the H.264 parser, this parser
will simply return that there is NO_NAL if some of these bytes are missing.
This is then properly special cased by parsers and decoders. Add a test to
ensure we don't break this in the future.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3234>
The appropriate return value for incomplete NAL header should be
GST_H264_PARSER_NO_NAL_END. This tells the parser element to
gather more data. Previously, it would assume the NAL is corrupted
and would drop the data, potentially causing stream corruption.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3234>
The flowcombiner and active_streams shouldn't be cleared in the
mse-bytestream variant, only in the mss-fragmented one. Otherwise the
soft reset leaves qtdemux in a state where it still believes that it has
streams, but they've been cleared. In that case, a null pointer
dereference happens and the app crashes.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4199>
Previously, reassigning loop index l in nicestream.c
could cause a segfault if l->data was null, as it could
reassign l to a null variable, triggering the loop
postassignment l->next, which then segfaults due to
l now being null. It is instead moved into the loop.
_delete_transport already performs the reassignment
inline.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4192>
In gst_video_info_dma_drm_to_caps() the caps are newly created, so there's no
need for make it writable. In gst_video_info_dma_drm_from_caps() a copy of the
caps is done, which implies a gst_caps_make_writable().
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4195>
In webrtc_data_channel_send functions, both data and string,
an early return on a non-open datachannel caused it to leak
the buffer used for pushing to appsrc, meaning any buffer
sent after leaving the open state was leaked in full.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4191>
When using such a launch line:
fakesrc ! "audio/x-opus, channel-mapping=(int)<0, 1>" ! fakesink
the caps string, with spaces escaped but no quotes gets passed to
gst_caps_from_string(), which then fails to parse the array because it
contains spaces.
When using an explicit capsfilter instead:
fakesrc ! capsfilter caps="audio/x-opus, channel-mapping=(int)<0, 1>" ! fakesink
the caps string, with spaces escaped and quotes gets passed through
gst_value_deserialize, which first calls gst_str_unwrap() on it and only
then gst_caps_from_string() on the result.
This fixes the inconsistency by using a custom version of str_unwrap()
in the parser, which doesn't expect a quoted string.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4181>
When copying a buffer, for example with gst_buffer_make_writable(), the
new buffer might reference the same GstMemory as the src buffer,
making those memories not writable. If the src buffer gets disposed
first it should return to its buffer pool, but since some of its
memories are not writable it gets discarded and new buffer/memory gets
allocated.
Solves this by making the new buffer keep a reference to the src buffer,
that ensures that by the time the src buffer gets disposed no other
buffer are referencing its memories and it can thus return safely to its
pool.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4176>
gst_buffer_add_parent_buffer_meta() is used when a GstBuffer uses
GstMemory from another buffer that was allocated from a pool. In that
case we want to make sure the buffer returns to the pool when the memory
is writable again, otherwise a copy of the memory is created. That means
the child buffer must drop its ref to the memory first, then drop the
ref to parent buffer so it can return to the pool when it is the only
owner of the memory.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4176>
This is already done for every other calls to send_packet. The deadlock occures
since FFMPeg 6.0. The decoder tries to get a buffer from a thread during
the draining process, and blocks trying to get the video decoder stream lock
already heald by the drain function.
Fixes#2383
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4171>
If the input is not a DMABuf, attempt to copy into a DRM Dumb
buffer and import it has a DMABuf. This will offload the
compositor from actually doing this copy (needed to handle SHM)
and may allow the software decoded stream to be rendered to
an HW layer, or even reach through some better accelerated
GL import path.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3801>
This allow simplifying the GstVideoInfo handling in the sinks. Instead
of having to update a video info for the import, the sink can simply pass the
video info associated with the caps and rely on the VideoMeta in the GstBuffer
to obtain the appropriate offset and stride.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3801>
As we don't render into the widget directly, there is no "initial" draw
happening. As a side effect, the internal aspect ratio adapted display
width/height is never initialize leading to assertions when handling navigation
events.
gst_video_center_rect: assertion 'src->h != 0' failed
Simply queue a redraw after setting the widget format in order to fix the issue.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3801>
This allow allocating memory from any DRM driver that supports this
method. It additionally allow exporting DMABuf. This allocator depends
on libdrm and will be stubbed if the dependency is missing. This is derived
from kmssink dumb allocator.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3801>
GStreamer 1.18 changed the serialization of enums.
This patch updates gsttr-stats.py to handle the new format.
In absence of that, the script was failing like this:
```
Traceback (most recent call last):
File "/home/ntrrgc/Apps/gstreamer/./subprojects/gst-devtools/tracer/gsttr-stats.py", line 224, in <module>
runner.run()
File "/home/ntrrgc/Apps/gstreamer/subprojects/gst-devtools/tracer/tracer/analysis_runner.py", line 42, in run
self.handle_tracer_entry(event)
File "/home/ntrrgc/Apps/gstreamer/subprojects/gst-devtools/tracer/tracer/analysis_runner.py", line 27,
in handle_tracer_entry
analyzer.handle_tracer_entry(event)
File "/home/ntrrgc/Apps/gstreamer/./subprojects/gst-devtools/tracer/gsttr-stats.py", line 114, in handle_tracer_entry
key = (_SCOPE_RELATED_TO[sv.values['related-to']] + ":" + str(s.values[sk]))
KeyError: 'thread'
```
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4155>
gstcudaloader.cpp defines GST_DEBUG_CATEGORY (gst_cudaloader_debug);
but it wasn't initializing it anywhere.
This caused the following error to be logged by gst-plugin-scanner when
libcuda.so.1/nvcuda.dll couldn't be loaded, e.g. in systems without
CUDA:
(gst-plugin-scanner:39618): GStreamer-CRITICAL **: 14:40:22.346:
gst_debug_log_full_valist: assertion 'category != NULL' failed
This patch fixes the bug by initializing the category in
gst_cuda_load_library_once_func() before any logging occurs.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4154>
This patch adds documentation to the 'log' tracer and amends the design
document of Tracers to replace a misleading example of the 'log' tracer
with a different example that uses tracer arguments with tracers that do
actually handle said arguments.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4153>
These days you're can use minFrameDuration and maxFrameDuration which
are CMTime with fractional values. That way we don't need to convert
between double and fractions in a really weird way.
This fixes really odd fractional values exposed in caps, like:
2000000/76923, 1000000/37037, 5000000/178571, 10000000/344827, 10000000/333333
Which are actually just 26/1, 27/1, 28/1, 29/1, 30/1
We can also delete a lot of outdated code for iOS versions older than
7.0 by using newer APIs.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4134>
This fixes simplification of caps with GstFractionRange structures,
for example, this caps:
video/x-raw, framerate=(fraction)5/1; video/x-raw, framerate=(fraction)[ 5/1, 30/1 ]
can now be simplified to:
video/x-raw, framerate=(fraction)[ 5/1, 30/1 ]
instead of:
video/x-raw, framerate=(fraction){ 5/1, [ 5/1, 30/1 ] }
And this:
video/x-raw, framerate=(fraction)[ 2/1, 5/1 ]; video/x-raw, framerate=(fraction)[ 5/1, 30/1 ]
can be simplified to:
video/x-raw, framerate=(fraction)[ 2/1, 30/1 ]
instead of
video/x-raw, framerate=(fraction){ [ 2/1, 5/1 ], [ 5/1, 30/1 ] }
This fixes overly-complicated GL caps set by avfvideosrc on macOS and
iOS when capturing from a webcam.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4132>
Removing a meta from a buffer means one doesn't have access to it
anymore. Instead use the already reffed composition directly.
Fixes a use-after-free in the following pipeline:
... ! vulkanupload ! timeoverlay ! vulkanoverlaycompositor ! ...
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4143>
As specified in EIA/CEA-608-B section 8.4:
When closed captioning is used on line 21, field 2, it shall conform
to all of the applicable specifications and recommended practices as
defined for field 1 services with the following differences:
a) The non-printing character of the miscellaneous control-character pairs
that fall in the range of 14h, 20h to 14h, 2Fh in field 1, shall be replaced
with 15h, 20h to 15h, 2Fh when used in field 2.
b) The non-printing character of the miscellaneous control-character pairs
that fall in the range of 1Ch, 20h to 1Ch, 2Fh in field 1, shall be replaced
with 1Dh, 20h to 1Dh, 2Fh when used in field 2.
This means simply switching the "field" field in the caps isn't enough for
converting raw 608 from one field to another, some control codes also
need to be amended.
+ Adds simple test
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4126>
GstBufferPool implementation was referenced for this GstD3D11PoolAllocator,
for example GstAtomicQueue, various atomic operations, and GstPoll ones.
However, such combination seems to be almost pointless
since gst_poll_{read,write}_control() takes mutex and also
GstPoll uses Win32 event handle internally.
Use simple SRWLOCK and CONDITION_VARIABLE instead, and don't make things
complicated/inefficient.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2887>
When we run Cheese 41.1 on our imx platform, Cheese preview freeze
at first frame.
During pipeline state changing from NULL to PLAYING, if there are
both elements that state change asynchronously and state change
with no preroll in the bin, the element inside may send ASYNC_DONE
message to it, while the bin's pending state is VOID_PENDING.
In this case, the bin will not post ASYNC_DONE message to parent
bin, which makes parent bin thinks that there are still elements
in it that haven't completed state changing, causing the pipeline
freeze in an intermediate state.
This commit modifies the bin_handle_async_done() function. When the
bin, whose pending state is VOIDING_PENDING, receives the ASYNC_DONE
message, it will also post this message to its parent bin.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3490>
A flush is resetting or not depending on the reset_time argument in the
FLUSH_STOP event is set.
Resetting flushes reset the running time to zero and clear any existing
segment. These are the kind of flushes used by flushing seeks, and by far the
most common. Non-resetting flushes are much more niche, used for instance for
quality changes in adaptivedemux2 and MediaSource Extensions in WebKit.
A key difference between the seek use case and the quality change use case is
that the latter is much more removed from the player. Seeks generally occur
because an user request it, whereas quality changes can be automatic.
Currently, there are three notable cases where position queries fail:
(a) before pre-roll, as there is no segment yet. This is one is understandable,
as for at least some time before pre-roll, we cannot know if a media stream
would start at 0 or any other position, or the duration of the stream for that
matter.
(b) after a resetting flush caused by a seek. This kind of flush resets the
segment, so it's not surprising position queries fail. This is inconvenient for
applications, as it means they always need to handle position reporting (e.g.
in UI) separately every time they request a seek, e.g. by caching the seek
target and using it when the position query fail. I'm not fond of this
behavior, as it's unintuitive and makes GStreamer harder to use, but at this
point could be difficult to change and it's not within the scope of this
proposal.
(c) after a non-resetting flush, e.g. caused by a quality change. The segment
is not reset in this case. Position queries work until a FLUSH_STOP is sent.
Querying position after a FLUSH_START but before a FLUSH_STOP works, and
returns the position the sink was at the moment the FLUSH_START was received.
**This in fact the only reliable way (short of adding probes to the sink
element) to get this position**, as FLUSH_START receival is asynchronous with
playback.
In the case (c), as of currently, position queries fail once the FLUSH_STOP is
received. But unlike in (b), the application has no position to fall back to,
as the FLUSH_START was initiated by elements inside the pipeline that are in a
lower layer of abstraction. Specific applications that have control of both the
player and the internal element doing the flushing -- such as WebKit -- can
still work around this problem through layer violations (lucky!), but this
still puts in question this behavior in GStreamer.
This patch fixes this case by amending the position query handler of basesink,
which was previously erroneously returning early with "wrong state", even
though the flush occurs in PAUSED or PLAYING.
A unit test checking this behavior has also been added.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3471>
The code wants to prepend one byte to every byte pair. It correctly did
so by working backwards pair-wise, but then didn't work backwards
instead of each individual pair / future triplet, overwriting
information before attempting to read it.
The code also failed to update the len pointer after prepending.
This fixes both issues.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4100>
The abort() method of SourceBuffer in Media Source Extensions is
expected to flush the demuxer and discard the current fragment,
if any. The configuration of tracks, if any, should be preserved.
qtdemux has different behavior for flush events depending on the
context.
This patch activates the intended behaviour only for streams of the
VARIANT_MSE_BYTESTREAM type, conformant to the ISO BMFF Bytestream
specification[1]. This flush behaviour is the same as the one
already in use for adaptivedemux sources.
[1] https://www.w3.org/TR/mse-byte-stream-format-isobmff/https://bugzilla.gnome.org/show_bug.cgi?id=795424
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4101>
Removing sockets from the epoll for cancellation is unreliable and might
not be thread-safe. Rather, have SRT watch a FD from the cancellable if
available. Keep the cancellable cancelled while we're not open.
Use the regular single-socket `sock` and `poll_id` fields for the
listening thread instead of duplicating them.
Before polling we need to check the socket state. SRT closes broken
sockets by itself and when the epoll contains our cancellation FD it can
no longer be empty, which was an error before.
Treat more failures in the read and write operations as an opportunity
to try a reconnect.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4087>
Seems that SRT can remove the socket from the poll by itself when the
connection gets closed. Consider this an error condition and ensure we
only "abort successfully" when we're actually trying to unlock.
Needs more investigation but this is enough to prevent the element from
getting stuck not reporting an error.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4087>
In tests in the rust bindings we end up with 2 thread initializing
concurrently, and it should not be a problem, -validate should be MT
safe.
Using a recursive mutex as we might recursively init for some reason
and we are not on the hot path here in any case.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4089>
Recursively invoking the NSMainLoop can cause crashes in
applications that don't expect it. Instead of waiting for
permission to be granted, move the wait later - until we
actually need device permissions when starting the capture
session. That moves the wait into the streaming thread
instead of the application thread that's setting the pipeline
state to READY.
Instead of a manual state change implementation to open
and close the device, use the basesrc start/stop methods that
are intended for the purpose.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4083>
There may be garbage or some bits before a SOI comes in some problematic
mjpeg streams. For example, some network error may cause the EOI marker
of the previous frame lost, and when the new frame's SOI comes, we still
use the state of the last frame, which will generate errors.
For this kind of frames without EOI, if that frame already has some data
(the SOS segment is detected), we still push it as a frame with CORRUPTED
flag set. But if not, we just discard all the data before the new SOI.
Co-Authored-By: Víctor Jáquez <vjaquez@igalia.com>
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4039>
The previous implementation was a bit primitive, assuming the subclass
had registered a template name starting with sink_ . Instead make
the effort of parsing the actual template name, and use that to generate
the final pad name.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4032>
This patch prevents a possible race condition from taking place between the EOS event handling and rtcp send
function/thread.
The condition starts by getting the GST_EVENT_EOS event on the send_rtp_sink pad, which causes two core things
to happen -- the event gets pushed down to the send_rtp_src pad and all sessions get marked "bye" prior to
completion of the event handler. In another thread the rtp_session_on_timeout function gets called after an
expiration of gst_clock_id_wait in the rtcp_thread function. This results in a call to the
ess->callbacks.send_rtcp(), which is configured as a function pointer to gst_rtp_session_send_rtcp via the
RTPSessionCallbacks structure passed to rtp_session_set_callbacks in the gst_rtp_session_init function.
In the race condition, the call to gst_rtp_session_send_rtcp can have the all_sources_bye boolean set to true
while GST_PAD_IS_EOS(rtpsession->send_rtp_sink) evaluates to false. This is the result of gst_rtp_session_send_rtcp
running before the send_rtp_sink's GST_EVENT_EOS handler completes. The exact point at which this condition occurs
is if there's a context switch to the rtcp_thread right after the call to rtp_session_mark_all_bye in the
GET_EVENT_EOS handler, but before the handler returns.
Normally, this would not be an issue because the rtcp_thread continues to run and indirectly call
gst_rtp_session_send_rtcp. However, the call to rtp_source_reset sets the sent_bye boolean to false, which ends up
causing rtp_session_are_all_sources_bye to return false. This gets passed to gst_rtp_session_send_rtcp and the EOS
event never gets sent.
The race condition results in the EOS event never getting passed to the rtcp_src pad, which prevents the bin and
pipeline from ever completing with EOS.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3798>
These checks were introduced to prevent exposing ARGB64/RGBA64 in the caps
when running on M1 Pro/Max with macOS <13 because of a bug in VideoToolbox.
Unfortunately, the initial buffer size of 15 is too short when running
in a VM - the CPU brand string there looks like "Apple M1 Pro (Virtual)",
which due to its length causes sysctlbyname to return -1, resulting in
broken formats still showing up in the caps.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4080>
We did several things to enable the new memory logic in msdkdec:
(1) We always use video memory for decoder in linux path;
(2) We give negotiated pool to alloc_pool stored in GstMsdkContext which
will be used in callback mfxFrameAllocator:Alloc to alloc surfaces as
MediaSDK needs, and this pool is also available for decoder itself;
(3) We modify decide_allocation process, that is we make pool negotiaion
before gst_msdk_init_decoder to ensure the pool is decided and ready for
use in mfxFrameAllocator:Alloc callback; then we will consider the case
when we need to do the gpu to cpu copy.
(4) In gst_msdkdec_finish_task, we modify the way for copy following the
logic in (3).
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3439>
Add a pool creation function name as 2 for later use which will create
va pool for video memory in linux and keep system pool for windows.
This gst_msdkdec_create_buffer_pool2 will replace gst_msdkdec_create_buffer_pool
when all the memory allocation modifications are ready in the commits after.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3439>
