This adds a non-thread safe refcount to the GstV4l2Request. This will
allow holding on more then one request in order to implement render
delay. This is made non-thread safe for speed as we know this will all
happen on the same streaming thread.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1881>
Starting from this patch, all queue and dequeue operation happening
on V4L2 is now abstracted with the request. Buffers are dequeued
automatically when pending requests are marked done and only 1 in-flight
request is now used.
Along with fixing issues with request not being reused with slice
decoders, this change reduces the memory footprint by allocating only
two bitstream buffers.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1881>
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>
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>
