Spec says:
In a frame picture top_field_first being set to ‘1’ indicates that the
top field of the reconstructed frame is the first field output by the
decoding process. top_field_first being set to ‘0’ indicates that the
bottom field of the reconstructed frame is the first field output by
decoding process.
Here, the "output" should be interpreted just as the output order, not
including the decoding order. The field should be decoded as the order
they comes in the stream. Namely, no matter top_field_first is 0 or 1,
the first coming field is the first one to be decoded.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1929>
In case that "pic_order_cnt_type" is equal to zero, ref picture
list for B slice should not include non-existing picture
as per spec 8.2.4.2.3. And, the second field is not needed
for the process of frame picture reference list construction
since it needs to be frame unit, not field picture in that case.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1812>
We were trying to construct reference picture list even for
I slice before this commit. Reference list is required only for
P, SP and B slices. Also, if all existing reference pictures
are gap pictures, we don't need to construct lists.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1812>
Initial support for interlaced stream. Subclass should implement
new_field_picture() vfunc. Otherwise, baseclass will assume that
subclass doesn't support interlaced stream.
Restrictions:
* Reference picture modification process for interlaced stream
is not implemented yet
* PAFF (Picture Adaptive Frame Field) is not properly implemented.
* Field display ordering (e.g., top-field-first) decision should
be enhanced via picture timing SEI parsing
* Gap in field picture should be handled
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1534>
Managing reference picture type by using two variables
(ref and long_term) seems to be redundant and that can be
represented by using a single enum value.
This is to sync this implementation with gstreamer-vaapi so that
make comparison between this and gstreamer-vaapi easier and also
in order to minimize the change required for subclass to be able
to support interlaced.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1534>
This will save the last independent slice and fill in the missing
information for dependent slices. This was left over during the porting
from gstreamer-vaapi. The private variable prev_independent_slice was
already there.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1750>
* Move all DPB bumping process into GstH265Dpb internal
* Handle DPB add process in GstH265Dpb struct
* Make implementation to be 1:1 mappable with hevc specification
* Fix wrong DPB bumping implementation especially when no_output_of_prior_pics_flag
was specified.
With fixes from Nicolas Dufresne <nicolas.dufresne@collabora.com>
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1748>
VA-API needs AC and DC quant scales for both luma and chroma, and the loop
filter level for current frame, but these values are not available outside
the private GstVp9Parser structure. And these values may change from frame
to frame, so they are picture specific.
This patch add GstVp9Segmentation structure array to GstVp9Picture to expose
it to derived classes. This approach is safer than passing the parser at
picture handling flow.
Also, this patch, in order to solve Documentation CI, mark as private the
GstVp9Picture structure.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1700>
In order to know the chroma format, besides profile, subsampling_x and
subsampling_y are needed (Spec 7.2.2 Color config semantics). These values are
in GstVp9Parser but not in GstVp9Framehdr.
Also, bit_depth is available in parser but not frame header. Evenmore, those
values are copied to picture structure later.
In case of VA-API, to configure the pipeline, it is require to know the chroma
format and depth.
It is possible to know chroma and depth through caps coming from vp9parser, but
it requires string parsing. It would be less error prone to get these values
through the parser structure at new_sequence() virtual method.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1700>
Move the show_frame check from sub class to vp8 decoder's base class.
Calling the sub class' output_picture() function only when the frame
is displayed and marking the other automatically as decode only.
This is done to avoid logic and code repetition in subclasses.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1670>
This is to avoid having to create a reference chain in decoders from
GstVideoCodecFrame to GstH264PIcture to implementation wrapper.
So this change introduces:
- gst_h264_dpb_remove_outputed (dpb)
- gst_h264_dpb_get_picture(dpb, system_frame_num)
- gst_h264_decoder_get_picture (dec, system_frame_num)
In order to ensure that frames can be looked up during the draining
process, we now first remove all (including reference) frames that
have been outputed but are still in the DPB. Then for each remaining
buffers, we remove it from the DPB to reach reference 1 and output it.
Previously we could take all not outputed outside of the DPB which would
prevent lookup by the base class.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1449>
... when gst_video_decoder_finish_frame() is called.
Some subclasses attach GstBuffer to GstH264Picture as an user data
which will increase reference count of the buffer. It would result
to buffer copy per every frame.
Background here is, GstVideoDecoder wants writable output buffer for
GstMeta handling, and if the output buffer is not writable
(i.e., reference count is not one), the buffer will be copied.
Even if underlying GstMemory wouldn't be copied, buffer copy operation
will introduce extra memory allocation overhead which is not optimal.
By this modification, subclass might be able to receive the last
reference to GstH264Picture
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1449>
All subclasses are retrieving list to get target output frame, which
can be done by baseclass. And pass the ownership of the GstH264Picture
to subclass so that subclass can clear implementation dependent resources
before finishing the frame.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1449>
There are some streams, with HRD, where the the calculated
max_dpb_frames is zero (max_dpb_mbs is less than size mb). In order to
get the dbp size it is required to rely on the VUI parameters if they
are present.
According to the spec Annex E.2.1
**max_dec_frame_buffering** specifies the required size of the HRD
decoded picture buffer (DPB) in units of frame buffers. It is a
requirement of bitstream conformance that the coded video sequence
shall not require a decoded picture buffer with size of more than
Max(1, max_dec_frame_buffering) frame buffers to enable the output of
decoded pictures at the output times specified by dpb_output_delay of
the picture timing SEI messages. The value of max_dec_frame_buffering
shall be greater than or equal to max_num_ref_frames. An upper bound
for the value of max_dec_frame_buffering is specified by the level
limits in clauses A.3.1, A.3.2, G.10.2.1, and H.10.2.
When the max_dec_frame_buffering syntax element is not present, the
value of max_dec_frame_buffering shall be inferred as follows:
– If profile_idc is equal to 44, 86, 100, 110, 122, or 244 and
constraint_set3_flag is equal to 1, the value of
max_dec_frame_buffering shall be inferred to be equal to 0.
– Otherwise (profile_idc is not equal to 44, 86, 100, 110, 122, or 244
or constraint_set3_flag is equal to 0), the value of
max_dec_frame_buffering shall be inferred to be equal to MaxDpbFrames.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1381>
Using glist requires a lot of small allocation at runtime and also
it comes with a slow sort algorithm. As we play with that for very
frame and slices, use GArray instead. Note that we cache some arrays
in the instance as there is no support for stack allocated arrays
in GArray.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1238>
In case of IDR, any previously decoded pictures must be drained
before the IDR and POC of IDR should be zero. So we can output
IDR immediately. Also, when POC of current picture is expected to be
the next output POC, decoder can output the picture as well
without waiting.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1211>
... to prevent requesting decoding before the preparation.
For instance, baseclass should not request decoding a picture if there
is no parsed valid headers, since subclass is most likely
not ready to decoding it.
As per specification in A.3.1 h) and A.3.2 f), the maximum size of the DPB is
16. Fix the maximum in the fine and fix the formula to use MIN instead of MAX
so that we no longer always use the maximum for the profile/level.
If decoding failed because end_picture() failed, set the picture to
nonexisting, this way output_picture() will be skipped. This avoids confusing
special cases in output_picture() implementation.
See C.5.2.2 Output and removal of pictures from the DPB.
If the number of pictures in the DPB is greater than or equal to
sps_max_dec_pic_buffering_minus1[HighestTid] + 1, then the picture
should be outputted.
